WATER POLLUTION CONTROL RESEARCH SERIES
16080 DVF 1^/70
Development of Phosphate-Free
Home Laundry Detergents
ENVIRONMENTAL PROTECTION AGENCY • WATER QUALITY OFFICE
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- about our cover
The cover illustration depicts a city in which man's activities coexist
in harmony with the natural environment. The Water Quality Control
Research Program has as its objective the development of the water
quality control technology that will make such cities possible. Previously
issued reports on the Water Quality Control Research Program include:
Report Number Title/Author
16080DRX10/69 Stratified Reservoir Currents; by Oregon State Univ.,
Corvallis, Ore.
Io080 06/69 Hydraulic and Mixing Characteristics of Suction Mani-
folds; by Univ. of Wash., Seattle, Wash.
16080 10/69 Nutrient Removal from Qrriched Waste Effluent by
the Bydroponic Culture of Cool Season Grasses; by
Jas. P. Law. Robt. S. Kerr Water Res. Ctr., Ada, Okla.
16080 11/69 Nutrient Removal from Cannery Wastes by Spray Irriga-
tion of Grassland; by Robt. S. Kerr Water Res. Ctr.,
Ada, Okla.
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DEVELOPMENT OF PHOSPHATE-FREE
HOVE LAUNDRY DETERGENTS
by
IIT RESEARCH INSTITUTE
Technology Center
Chicago, Illinois 60616
for the
WATER QUALITY OFFICE
ENVTOONMENTAL PROTECTION AGENCY
Program #16080 DVF
Contract No. 14-12-575
December, 1970
For sale by the Superintendent of Documents, U.S. Government Printing Office
Washington, D.C., 20402 - Price $1
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WATER POLLUTION CONTROL RESEARCH SERIES
The Water Pollution Control Research Reports describe the
results and progress in the control and abatement of pol-
lution in our Nation's waters. They provide a central
source of information on the research, development, and
demonstration activities in the Water Quality Office,
Environmental Protection Agency, through inhouse research
and grants and contracts with Federal, State, and local
agencies, research institutions, and industrial organizations.
Inquiries pertaining to Water Pollution Control Research
Reports should be directed to the Head, Project Reports
System, Planning and Resources Office, Office of Research
and Development, Water Quality Office, Environmental
Protection Agency, Room 1108, Washington, D. C. 20242.
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WQD Review Notice
This report has been reviewed by the Water Quality Office
and approved for publication. Approval does not signify
that the contents necessarily reflect the views and
policies :of the Water Quality Office, nor does mention
of trade names or commercial products constitute endorsement
or recommendation for use.
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ABSTRACT
Basic studies were performed towards the development of
phosphate-free home laundry detergents. A number of
surfactants were synthesized for the purpose of incorpora-
tion into phosphate-free detergents. These surfactants
were selected with the idea that they might possess hard
ion chelating properties and/or be unaffected by hard
water. The cleaning abilities of these materials were
compared to those obtained with the same formulations
containing a commonly used surfactant—namely, LAS.
In formulating these candidate surfactants, the loss of the
functions of phosphates was compensated for by increasing
the concentration of some of the common detergent builders
and the use of other additives. The surfactants were
formulated in compositions which, on a finished formulation
basis, contained a carboxymethylcellulose concentration of
2%. The silicate content was varied but was most
frequently used at levels above those which are currently
employed. Sodium acetate and sodium carbonate were
investigated as possible reservoirs of alkalinity.
Surfactant compatibility with sodium chloride and sodium
sulfate was also examined. Sodium citrate and trisodium
nitrilotriacetate, at moderate concentration levels, were
investigated for their value in combination with the
surfactants.
During the course of the project, five surfactants were
synthesized and fifteen detergent formulations were
screened. The detergency data of these formulations were
compared to the results obtained with a reference phosphate
containing detergent which was supplied by the Association
of Home Appliance Manufacturers (AHAM). Additionally,
comparison was made to a local commercial brand.
A few basic formulations performed well at specific hard-
ness levels under the test conditions employed and, while
the testing did not evaluate all aspects of cleaning, the
results leave little doubt that an acceptable phosphate-
free home laundry detergent can be developed.
This report was submitted in fulfillment of Program No.
16080 DVF, Contract No. 14-12-575, under the sponsorship
of the Federal Water Quality Administration.
Key Words: Detergents, algal control, formulation,
surfactants, eutrophication, linear alkyl
sulfonates, chelation, phosphates, organic
compounds, water pollution control, phosphate-
free detergents.
iii
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CONTENTS
Section Page
I Introduction 1
II Synthesis of the Surfactants 3
III Surfactant Biodegradability 9
IV Detergency Formulations and Evaluations 13
V Acknowledgments 27
VI References 29
VII Appendix 31
iv
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TABLES
No. Page
1 Biodegradability of Surfactants
by the Presumptive Test 12
2 Percent Soil Removal From Soiled Cotton Cloths
by Waters of Varying Hardness 14
3 % Compositions of Test Formulations 16
4 Individual Effects of Various Builders
and Additives 22
v
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CONCLUSIONS
The basic studies of this program indicate that a phosphate-
free home laundry detergent can be prepared on a custom
basis in which regional water hardness levels are con-
sidered. This can be accomplished through the use of
specific anionic surfactants in combination with currently
used builders and other readily available chemicals.
Selection of the anionic surfactant is dependent on wash
water hardness. The three surfactants to be considered are
sodium dodecylbenzenesulfonamidoethyl sulfate
(C12H25-C5H4-SO2NHCH2CH20SO3Na, IA) , methyl 3-dodecyl-
benzoyl-3(2)-(sodium sulfonatojpropionate (Ci2H25~c6H4-
COCH(SO3Na)CH2CO2CH3, II) and sodium dodecylbenzene-
sulfonate (Ci2H25-CeH4-SO3Na, LAS). Surfactants IA and
II can be built to give a hard water cleaning ability
which is better than with LAS but do not show overall
superiority when soft water performance is considered.
Carboxymethylcellulose (CMC), foam stabilizer and silicate
were the three common detergent components which were
retained in all formulations. A silicate content of
8-10% was determined to be the useful optimum range. Use
of sodium acetate at concentrations which were equal to or
greater than the acid equivalency of a 40% sodium tripoly-
phosphate content improved the detergency of the three
surfactants but did not supply enough alkalinity to the
wash water especially at the lower formulation concen-
trations. In the same vein, sodium carbonate is capable
of raising the pH, but its use at high detergent
concentration (10-40%) is detrimental to the anionic
detergent formulations which were screened. All satis-
factory formulations possessed sodium acetate; thus we
have the following nuclear composition:
20% - Surfactant
2% - Carboxymethylcellulose
2% - Foam stabilizer
8-10% - Silicate
20-30% - Sodium acetate
(inert balance = water)
VI
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By itself, the preceding nuclear composition was found to
be adequate in soft water (50 ppm) only when compound II
or LAS was used as the surfactant. This same type of
formulation was effective in moderately hard water
(135 ppm) with either surfactants IA, II or LAS, the best
overall performance being that which contained IA.
(Though the LAS combination supplied the best cleaning
ability in the normal use region of 0.25%, its poor low
concentration effectiveness and decreased high concen-
tration ability did not make it the best choice.) This
same formulation containing IA, also showed good results
in hard water (300 ppm), while the LAS containing
composition placed a close second.
Addition of 15% sodium sulfate to the above basic formu-
lation enhanced the effectiveness of the surfactant II
composition which also gave good screening results at the
135 ppm hardness level. Similarly, in hard water, the
sulfate containing formulation which possessed IA was good
and about equal to that without sulfate, thus allowing
for the inclusion of sodium sulfate as a "filler"
component.
In combination with surfactant, CMC, foam stabilizer and
silicate, trisodium nitrilotriacetate and sodium citrate
were found to be of significant value only in hard water.
Thus, the presence of these additives in soft water
would seem to be unnecessary. The hard water detergency
contribution by nitrilotriacetate is superior to that of
citrate on an equal weight basis at a composition level of
16.8%. The addition of NTA to the aforementioned nuclear
composition did not improve the overall effectiveness for
any of the surfactants.
VI1
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RECOMMENDATIONS
In order to develop the optimum composition(s) which can
be intensively evaluated, the effects of a number of
remaining factors must be determined. These factors fall
into the general categories of (1) biological considera-
tions, (2) ways to moderately increase wash water alkalinity,
(3) evaluation of a select few additional additives,
(4) test cloth variation in detergency screening, (5) soil
anti-redeposition properties, and (6) optimization of the
surfactant concentration as well as the surfactant hydro-
carbon chain length.
Since the commercially unavailable surfactants, IA and
II, are useful in phosphate-free compositions, it is
mandatory that they be subjected to further biological
testing before proceeding with development of formulations
in which they might be incorporated. Aside from their
performance in the confirming biodegradability test, the
toxicities of these materials to snails, algae and fish
should be determined by the 96-hour dynamic TLm.
A number of approaches can be taken to help increase the pH
of the wash water. The most obvious is to increase the
ratio of sodium oxide to silicon dioxide by using a
different type of sodium silicate. Although this would
probably be a successful solution to the problem, a higher
sodium oxide content might be too caustic, requiring a
hazardous warning label for the final formulation(s).
Whereas a high sodium carbonate concentration is detri-
mental to the type of formulation which we have investi-
gated, it is probable that smaller amounts of this material
(2-4%) would raise the pH and allow for adequate per-
formance. A novel approach to pH control might be
accomplished through the use of small amounts of calcium
hydroxide; this might also improve some compositions which
performed poorly in soft water but reasonably well in hard
water. The rationale for the use of calcium hydroxide is
based on the fact that its water solubility decreases with
increasing temperature and it possesses an inverse pH-
temperature relationship. For example, a saturated
aqueous solution of calcium hydroxide possesses a
(buffered) pH of 13.4 at 0°C and 11.5 at 60°C while its
water solubility is 0.185 g/100 ml at 0°C and 0.077
g/100 ml at 100°C. In hard water, the presence of calcium
would help to suppress the solubility through the common
ion effect on its solubility constant.
viii
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Of the many potential sequestering agents for which one can
test detergent efficacy, tartrate, lactate and isethionate
would be worthwhile for investigation due to their relative
cheapness and biodegradability. These additives should be
evaluated in combination with the different surfactants
within the basic formulations.
The surfactant concentration should be kept constant
(at 20%) while optimizing the other detergent components.
Because test soils possess different cleaning
characteristics, at least one other test cloth should be
used for evaluations. At this time, we would recommend
the use of the "BMPA" soiled cotton test cloth which is
imported from Europe and is available through Testfabrics
Inc. EMPA also has cloths which are available with
various stains such as wine, blood, ink, milk and cocoa.
In developing the finished formulation(s), a good cleaning
ability is readily determined by the routine test procedure
and infers an acceptable level of the soil anti-
redeposition function; however, the detergent must be
specially evaluated for this property under heavy soil
loads to assure the fact that it possesses good all-around
performance.
Optimization of the surfactant concentration might be best
determined through critical micelle concentration studies
since optimum cleaning results are usually achieved in
the vicinity of this concentration region. These
determinations would be performed on the surfactants with
respect to their incorporation into formulations as well as
in combination with single components and by themselves.
In the best light this information could be utilized to
assemble a chemical equivalency table which would serve
the same type function as an isotonicity scale. Thus, the
various detergent components would be rated as to their
weight capabilities of contributing to the critical micelle
concentration and can be related to a sodium tripoly-
phosphate sample.
Since there is usually an optimum in the relationship
between hydrocarbon chain length and detergency, it would
seem prudent to ascertain the effects of varying the chain
length of at least one of the surfactants. The commercially
available Cn^-alkylbenzene, which was used to prepare the
surfactants of this project, is the same which is used for
the manufacture of LAS. The fact that an average GH.S
hydrocarbon length is optimum for LAS does not necessarily
confer optimum detergency in the different surfactant
structures which have been prepared. A slightly lower
chain length could optimize the detergent properties of
the types of surfactants which have shown promise.
ix
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BLANK PAGE
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SECTION I
INTRODUCTION
Eutrophication of the Nation's lakes has become a problem
which is causing great concern to government and industry.
Combined with other factors, the phosphates of detergents
as well as fertilizers help to promote this eutrophication.
Regardless of which condensed phosphate is used in
detergents, the end product, which is discharged into the
sewers, is that of ortho-phosphate. To exemplify the
severity of the phosphate problem, one has only to
consider the following approximate formulation which is
typical of a high-sudsing laundry detergent:
20% linear alkylbenzenesulfonate
40% condensed phosphates
14% sodium sulfate
4% sodium silicate
2% amide foam stabilizer
0.5% sodium carboxymethylcellulose
19.5% moisture and other minor components.
Thus, continued increase in the use of phosphate containing
detergents due to elevated cleaning demands and an increase
in the population will only serve to magnify a problem
which is already severe. This report deals with an
approach to the phosphate pollution problem—namely, the
development of phosphate-free home laundry detergents.
Our approach departs from the present-day detergent
technology which has developed over the past 25 years and
in which two companies dominate the industry. The functions
of phosphates in detergents can be briefly summarized as
follows:
1. Chelation of calcium and magnesium ions
2. Lowering of the critical micelle
concentration (cmc)
3. Soil suspension by deflocculation
4. Supply a reserve alkalinity at a
buffered pH of 10 to 11.
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Though other benefits are claimed for the phosphates, the
above four are the most important ones. Since alkyl-
benzenesulfonates and fatty alcohol sulfates (the most
popular surfactants used in the U. S.) are adversely
affected by calcium and magnesium ions, the hard ion
chelating function of phosphates allows for more efficient
cleaning by these materials. Our work seeks to circumvent
this problem by the use of surface active compounds which
could possess self-chelating properties or which are not
adversely affected by hard water. Thus, the candidate
surfactants would differ in performance from commercially
available surfactants insofar as the presence of calcium
and magnesium would either enhance or have no tangible
effect on their detergent action.
The phosphate detergency functions of soil deflocculation,
alkalinity and lowering of the cmc would be compensated
for by the use of other organic and/or inorganic salts.
Conceivably, the lowering of the critical micelle concen-
tration should be accomplished by the use of other electro-
lytes such as carbonates, sulfates or chlorides. The
primary contribution to soil suspension is normally
achieved through the use of carboxymethylcellulose (CMC)
and the elimination of the phosphate contribution could be
augmented by a concentration increase in this component.
The final phosphate function, that of alkalinity reserve,
should be served by carbonates and/or acetates.
This project then, consists of work in the areas of
surfactant synthesis, surfactant biodegradability testing
and formulation and evaluation of phosphate-free detergents,
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SECTION II
SYNTHESIS OF THE SURFACTANTS
The candidate surfactants are representative of four types
of surface active agents which might be self-chelating or
unaffected by hard ions. The first surfactant class is the
sulfated and sulfonated sulfonamides, represented by sodium
dodecylbenzenesulfonamidoethyl sulfate (C^2^25~(-'6^-4:-^^2~
NHCH2CH2OSO3Na), sodium dodecylbenzenesulfonamidoethyl-
sulfonate (Ci2H25-C6H4-SO2NHCH2CH2SO3Na) and sodium N-
methyl-dodecylbenzenesulfonamidoethylsulfonate
(c12H25-c6H4-s°2N(CH3)CH2CH2s°3Na) • T:he second class of
surfactants, alkylaroyKsulfo)propionates, is represented
by methyl 3-dodecylbenzoyl-3(2)-(sodium sulfonato)-
propionate (Ci2H25-CeH4-COCH(SO3Na)CH2CO2CH3) while sodium
2-dodecylaminoethanesulfonate (Cj2H25NHCH2s°3Na) represents
that of the amphoteric sulfonates. The final class is
that of the ketosulfone carboxylates; both compounds
involved here can be considered as levulinic acid deriva-
tives. The first species is dodecyl 3-levulinate sulfone
(CH3COCH(SO2C12H25)CH2C02Na) while the second is dodecyl
6-(4-keto)hexanoate sulfone (Ci2H25SO2CH2CH2COCH2CH2CO2Na).
Although the preceding compounds are not necessarily new to
the chemical literature, they are not in commercial
production. The following discussion gives the pertinent
synthetic information for these compounds. A more
detailed discussion of the procedures and analyses is
presented in the appendix.
Sulfated and Sulfonated Sulfonamides (Code No. I)
IA - Sodium Dodecylbenzenesulfonamidoethyl sulfate
(C12H25~C6H4~S02NHCH2CH2°S°3Na)
IB1 - Sodium Dodecylbenzenesulfonamidoethyl-
sulfonate (C.. 0Hot.-C,H.-SO_NHCH0CH_SO_Na)
12 ZD b 4 2. 2. 2 J
IB2 - Sodium N-Methyl-dodecylbenzenesulfonamidoethyl-
sulfonate (C, 0Hot.-C,H/.-SO0N(CH_)CH0CH0SO..Na)
L2. 23 b 4 £ J Z 2 3
All members of this class of surfactants were prepared from
the common intermediate, dodecylbenzenesulfonyl chloride
as illustrated in Scheme 1.
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Scheme 1
2C1SO H
C12H25-C6H5 ClGH^d* C12H25-C6H4-S02C1
Base
Base
NH( CH
Base
IA
C12H25-C6H4-S°3NHCH2-
IB1
* C12H25-C6H4-S°2N-
(CH3)CH2CH2
IB2
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The alkylbenzenesulfonylchloride (b) was prepared by adding
the chlorosulfonic acid to a cooled solution of the allcyl-
benzene in 1,2-dichloroethane. After applying gentle
aspiration, the crude solution was used "as is" in the
reactions with aminoethyl hydrogen sulfate (NH2CH2CH2OSO3H)/
taurine (NH2CH2CH2SO3H) , and N-methyltaurine (NH(CH3)CH2-
CH2SO3H) to yield surfactants IA, IB1 and IB2 respectively.
The dichloroethane solutions of b were added to aqueous
mixtures of the reagents containing sodium bicarbonate.
The reaction mixtures were maintained at a basic pH
throughout the addition by the use of sodium bicarbonate
as needed. After heating, the gelatinous product was
precipitated by the addition of saturated potassium chloride
solution, filtered by gravity and dried in a vacuum oven.
The somewhat gummy products were extracted with hot solvent
and the solvent was removed under reduced pressure to yield
the product.
The dried products were titrated with a standard cation
solution; the titrations indicated purities of 86%, 88%
and >95% for compounds IA, IB1 and IB2 respectively. The
qualitative features of the infrared and proton magnetic
resonance spectra were acceptable for the assigned
structures. A more detailed interpretation of the PMR
spectra indicated a purity of 75% for IB1 and 80% IB2. A
similar analysis was not possible for surfactant IA. The
detailed titration and analytical data are presented in
the appendix.
AlkylarovK sulfo)propionates (Code No. II)
II - Methyl 3-dodecylbenzoyl-3( 2) -(sodium sulfonato) -
propionate (CH-CH
The synthetic route to this surfactant is shown in
Scheme 2 .
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Scheme 2
(C1CH2CH2C1)
Step 1
CH3OH/H+/Reflux
(C1CH2CH2C1)'
Step 2
NaHSO /HO-1400
Pressure > C12H25-C6H4-C6H4-COCH( S°3Na) CH2C°2CH3
Step 3 XI
The acylation by maleic anhydride (Step 1) was accomplished
by adding the alkylbenzene (a) to the cooled mixture of
maleic anhydride and aluminum chloride in dichloroethane.
The reaction mixture was treated with a sulfuric acid-
isopropyl alcohol solution and the upper organic layer was
washed twice more with the acid-alcohol solution and then
with saturated sodium chloride solution. The crude pro-
duct was stripped of solvent under reduced pressure and
yielded the intermediate acid (c). The IR and PMR spectra
were in excellent agreement with the acrylic acid
structure, b. PMR data and titration with standard base
indicated good purity for this intermediate. This acid
was redissolved in dichloroethane and esterified with
methanol by azeotroping in the presence of sulfuric
acid (Step 2). After removing the dichloroethane under
reduced pressure, the residue was titrated with standard
ethanolic potassium hydroxide solution. The acid content
was less than 4%. PMR and IR data confirmed the esterifi-
cation.
Conversion of the acrylate (c) to the desired product (II)
was accomplished by the addition of sodium bisulfite
across the alkene function (Step 3). This reaction was
carried out in a Parr pressure reactor in the presence of
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water at 110-140°C. Titration of the final product by a
standard cation solution indicated a purity of 90%, while
PMR data showed the material to contain about 80% of the
desired surfactant (II). A detailed interpretation of the
analytical data is presented in the appendix. While the
sodium sulfonato group is shown in a specific location
within the molecular structure, the analytical data does
not prove this assumption. The sulfonato group can, in
fact, be in either the 2 or 3 position of the propionate
nucleus.
Amphoteric Sulfonates (Code No. Ill)
IIIA - Sodium Dodecylaminoethanesulfonates
IIIB - Sodium N-Hydroxyethyl-2-dodecylamino-
ethanesulfonate (CH
The yield compound IIIA, as prepared in accordance with
Scheme 3, was rather poor.
Scheme 3
en M Pressure.. ,-,
'12"25""2 ' "—"2^*2 3 a 200-225°
a b IIIA
This surfactant possessed poor detergent properties and
was dropped in the very early stages of screening.
Because of the poor detergent properties of the above
parent molecule, surfactant IIIB was not prepared.
Ketosulfone Carboxylates (Code No. TV)
IV A - Dodecyl 3-Levulinate Sulfone
The proposed synthetic route to the levulinate/ IVA is
shown in Scheme 4 .
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Scheme 4
CH_COCH_CHCO_H - r-> CH-.COCHBrCH,,CO_H
__0_ -.,,_ q 0
3 2 2. 2. Step 1 o 2. 2. Step 2.
CH0COCH(SR)CH0CO0Na > CH-COCH(SO_R)CH0CO0Na
j 2. 2. Step 3 3 222
The bromination of levulinic acid in benzene (Step 1)
supplied a product which contained three brominated isomers
and a small amount of starting material. This product
was found to be suitable for use in Step 2, where displace-
ment of the bromo group by mercaptide yielded a product
which was a mixture of two isomers, which included the
desired intermediate, c.
A number of attempts were made to oxidize the mixture of
thioethers to their sulfone derivatives as shown in Step 3
of Scheme 4. None of these experiments were successful in
supplying the desired surfactant IVA. We were therefore
unable to investigate the value of this type of surfactant
in phosphate-free formulations.
8
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SECTION III
SURFACTANT BIODEGRADABILITY
The biodegradabilities of surfactants IA, IB1, IB2 and II
were determined by the presumptive (shake culture) test.
A commercial sample of LAS was included as a control. Due
to its amphoteric properties, surfactant IIIA did not lend
itself to the spectrometric analysis of the procedure,
however, its poor detergent properties obviated the need
for this testing since it was eliminated as a candidate
surfactant.
General Conditions for Degradability by Microorganisms
Microorganisms are inoculated into flasks which contain a
chemically defined microbial growth medium and the test
surfactant. Aeration is accomplished by continuously
shaking the flask. Biodegradation is determined by
measuring the reduction in surfactant content during the
8-day test period which follows two 72-hour adaptive
transfers. Samples were withdrawn from the flask on the
seventh and eighth day as well as at the start of the test
period. These samples were analyzed for anion content by
the methylene blue method as generally described in the
following section. The average value obtained from the
seventh and eighth day samples were used to compute
biodegradability. The microbial inoculum was obtained
from the Metropolitan Sanitary District of Greater Chicago.
The surfactant sample size was 30 mg/liter of culture
medium.
According to this test, a surfactant is considered to be
biodegradable if reduction equals or exceeds 90%. If
surfactant reduction falls between 80% and 90% the results
are inconclusive and the material must be evaluated by the
confirming test before a conclusion can be reached. A
value below 80% in the presumptive test classifies the
material as not adequately biodegradable. Because we
processed the samples immediately, the use of formaldehyde
in the samples was unnecessary.
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General Procedure for Anion Analysis by the Methylene^
Blue Method
ATkylbenzenesulfonates (ABS), linear alkylbenzene-
sulfonates (LAS) and alkylsulfates form a blue/ chloroform
soluble salt with methylene blue. The intensity of the
blue color is measured spectrophotometrically at the
wavelength where the color intensity is proportional to the
concentration of this salt. The optical density of the
sample is then used to determine the anion content by
reference to a calibration curve which was prepared with
the specific surfactant.
The general procedure is as follows: The test sample
is mixed with a stock solution of methylene blue. After
allowing sufficient time for salt formation (1/2 hour) the
acidifed solution is extracted with aliquots of chloro-
form. The combined chloroform extract is washed with an
aqueous wash solution followed by backwashing of the
aqueous layer with chloroform. The chloroform back-
washings are combined with the original chloroform
extracts. Finally, the chloroform solution is brought to
volume (100 ml) after filtering through a pledget of glass
wool.
Thus, a requisite for the use of this analytical procedure
with our surfactants is that we obtain a straight line
relationship between optical density and concentration
at the wavelength of the analysis. The materials used as
surfactants IA, IB1, IB2 and II possessed this requisite
relationship. These reference calibrations are shown as
a composite in Graph 1 of the appendix. Though more than
one calibration was performed for each of the surfactants,
the Graph 1 composite shows the calibration which possessed
the least deviation from the straight line.
It is of interest to note that the tangents of the
calibration lines for the surfactants generally decrease
with increasing molecular weight of the anionic species.
The theoretical molecular weights of the anions are:
LAS = 325, IB1 = 432, II = 439, IA = 448 and IB2 = 446.
In the case of IA vs IB2 where the molecular weight are
almost equal, this relationship is reversed. This general
trend would be expected if the color contribution came from
the methylene blue cation. Thus, the lower the molecular
weight of the anion, the more molecules per unit weight
are available for the formation of the colored species.
The ratios of the tangents for the calibration lines are
crudely within 10% of the anionic molecular weights
relative to LAS. The wavelength of 652 mpi was checked
for each species involved and was found to be an acceptable
region.
10
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Results of Biodegradability Testing
The results of biodegradability testing are given in
Table 1. Since the testing of IA and II was initiated on
a different day than that of IB1 and IB2, the LAS control
data consist of two sets of values corresponding to the
IA, II and IB1, IB2 cycles.
All candidate surfactants show better than 85% biodegrad-
ability. It should be noted, however, that the LAS
controls are at values which are somewhat less than those
required for this species. This, of course, indicates
that the degrading activity of the culture is somewhat
less than what is normally expected.
11
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Table 1
BIODEGRADABILITY OF SURFACTANTS
BY THE PRESUMPTIVE TEST*
Sample
Time
(Days)
0
7
8
0
7
8
0
7
8
0
7
8
0
7
8
Surfactant Concentration Present
in Culture (uq/ml)a
LAS0 (Commercial Sample)
For IA and II For IB1 and IB2
Biodegradability
(X)
26.8
2.7
1.6
25.0
3.0
2.4
91.8% 89.2%
SURFACTANT IA
33.2
4.6
3.8
SURFACTANT IB1
25.8
4.0
3.2
SURFACTANT IB2
31.5
3.8
3.6
SURFACTANT II
25.5
3.8
3.6
87.3%
86.0%
88.3%
85.5%
*SOAP & DETERGENT ASSOCIATION, J. Am. Oil Chemists Soc., 42.
986 (1965); APHA, AWWA AND WPCF, STANDARD METHODS FOR THE
EXAMINATION OF WATER AND WASTE WATER, p. 297, BOYD PRINTING
CO., ALBANY, New York (1965).
Values given are the average of two determinations using
different sample sizes. The zero day sample value is derived
from analysis of a 1 and 2 ml aliquot, while the 7 and 8 day
determinations are derived from a 10 and 20 ml sample. The
value supplied by the reference calibration was divided by
the number of mis of inoculum used for the determination.
Theoretical zero time concentration is 30 jug/ml.
Calculated as percent removal using the found zero day
concentration as the starting amount and the average of the
7th and 8th day values as the final concentration.
cTesting of IA and II was initiated on a different day from
that of IB1 and IB2. LAS was included in each of the two
test cycles; therefore two sets of values are given for
this reference surfactant.
12
-------
SECTION IV
DETERGENCY FORMULATIONS AND EVALUATIONS
3 4
Test Procedure '
The detergency evaluations were carried out by washing
artificially soiled cloths in a Tergotometer which is a
simulated washing machine manufactured by the U. S. Testing
Co. This unit is the most convenient and practical from
the standpoint of screening tests. Other mechanical
devices, such as regular washing machines, would require
too much input of time, personnel and material. In this
procedure, three swatches of standard soiled cotton cloth
(4 1/2 x 5") were placed in each of the four Tergotometer
containers and the cloths were washed in solutions
containing the detergent at 0.1, 0.2, 0.3 and 0.5% on a
finished formulation basis. The fabrics were then washed
at 150 rpm for 15 minutes at 120°F. The cleaned cloths
were ironed after a 2-minute rinse cycle in the Tergotometer.
The reflectance of the washed cloths was then compared to
that of the soiled cloths using the green phototube of a
Hunterlab Model D40 reflectometer which was standardized
against a gray tile. \ In recording these readings, two
right angle reflectance values were recorded for each cloth
sample before and after washing. The average of the six
readings (two for each of the three cloths per wash
solution) was used to compute the percent soil removal
according to the following equation:
PSR = (RW-RS/RO-RS) x 100
where
PSR = Percent Soil Removal
R = Average reflectance of the washed fabric
(average of 6 readings, 2 for each of
3 cloths)
RS = Average reflectance of the unwashed
soiled cloth
RQ = Reflectance of the unsoiled cloth
(In the case of the U. S. Testing Co.
soiled cotton cloth, this value is
supplied with the control data for the
lot) .
13
-------
Commercially, at least three standard soiled cotton cloths
are available in the U. S.; two are American made and
one is European made. Additionally, a great number of
investigations have been reported in the literature on the
very important parameter of soil composition for the test
cloths. Thus, a number of standard soils have been
developed and investigated as being more practical (or
realistic) in their composition. The possible constituents
of soils range from the use of iron compounds^ and a clay-
oleic acid combination^ to the processing of vacuumed
carpet dirt.7 The U. S. Testing Co. soiled cotton cloth,
which was used in our work, is not easily cleaned by
distilled water and shows only a small variation in
cleanability when washed by plain water at hardnesses of
50, 135 and 300 ppm. Although some preliminary testing was
done on Testfabrics' (Inc.) soiled cotton cloth, the fact
that distilled water cleaned it almost as well as the
AHAM-2A reference detergent led us to prefer 'the U. S.
Testing Co. cloth. Table 2 gives the data which
illustrate the differences in cleanability between these
two cloths. Because there were differences between some
lots of the U. S. Testing Co. cloth, the AHAM-2A formu-
lation and a commercial product were tested in duplicate
on each new lot of this cloth. Thus, on the basis of a
reference, one could compare the results of tests which
were obtained from different lots of cloth.
Table 2
PERCENT SOIL REMOVAL FROM SOILED COTTON CLOTHS
BY WATERS OF VARYING HARDNESS
% Soil Removal at Given
Water Hardness (ppm as CaCO_)
0 50 135 300
U. S. Testing Co. 9.8% 8.7% 8.1% 8.2%
Testfabrics Inc. 57.8% 32.0% 24.2% 20.3%
Formulations
The following composition is typical of a high-sudsing,
phosphate containing laundry detergent:
20% Linear alkylbenzenesulfonate (LAS)
40% Sodium tripolyphosphate
14
-------
6% Sodium silicate
2% Amide foam stabilizer
0.5% Carboxymethylcellulose (CMC)
14% Sodium sulfate
19.5% Moisture and other inorganic components.
It should be noted that the above formulation excludes the
consideration of brighteners, bleaches and/or enzymes
which are present in a number of today's products.
Since the objective of this project is to develop an
efficient phosphate-free home laundry detergent, one must
compare the effectiveness of our formulations to that of a
comparable phosphate-containing detergent. The Association
of Home Appliance Manufacturers (AHAM) supplied a quantity
of a phosphate containing reference standard detergent
(No. 2A). The concentrations of the primary ingredients
of this detergent are as follows:
13% LAS
2% Fatty acid
2% Nonionic surfactant
1% Carboxymethylcellulose
6% Sodium silicate
47.5% Sodium tripolyphosphate (analyzed as
27.5% phosphorous pentoxide).
The absence of a foam stabilizer and the presence of fatty
acid in this formulation make it a low sudsing detergent.
This AHAM-2A detergent was used as a reference formu-
lation throughout our work. In addition, a local commercial
product was also used as a control and for comparative
purposes.
Table 3 lists the components and percent composition for
each formulation investigated ("A" through "O"). Each
Test Formulation (TF) is comprised of a small series
obtained by using different surfactants. For example, use
of LAS and surfactants IA, IB1, IB2, II and IIIA within
Test Formulation "A" (TF A), at the 20% concentration
specified, yields the "A" series which is comprised of 6
members, designated as TF A-LAS, TF A-IA, TF A-IB1,
TF A-IB2, TF A-IP and TF A-IIIA, respectively. The
15
-------
Table 3
% COMPOSITIONS OF TEST FORMULATIONS
(Finished Formulation Basis)
Component A
Carboxymethylcellulose 2.0
Cocodiethanol amide 2.0
Sodium
Si02
Na20
Sodium
Silicate (10.1)
7.2
2.9
Acetate
BCD
2
2
(10
7
2
22
.0 2.0 2.0
.0 2.0 2.0
.1) (10.1) (2.8)
.2 7.2 2.0
.9 2.9 0.8
.2 - 30.0
Trisodium Nitrilotriacetate -
Sodium
Sodium
Sodium
Sodium
Carbonate
Chloride
Sulfate
Citrate
Surfactant 20.0
Other
(H20) 65.9
15
20
28
40.0
_
.0 - -
_
.0 20.0 20.0
.7 25.9 43.2
E F G H I J K
2.0 2.0 2.0 2.0 2.0 2
2.0 2.0 2.0 2.0 2.0 2
(10.1) (10.1) (14.1) (10.1) (10.1) (10
7.2 7.2 10.1 7.2 7.2 7
2.9 2.9 4.0 2.9 2.9 2
30.0 - - - - 30
16.8 - 16
-
_ _ - 10.0
_ 10.0
_
20.0 20.0 20.0 20.0 20.0 20
35.9 49.1 61.9 55.9 55.9 19
.0 2.C
.0 2.C
.1) (10.1)
.2 7.2
.9 2.9
.0 22.2
.8 16.8
-
-
-
-
.0 20.0
.1 26.9
L M N
2.0 2.0 2.0
2.0 2.0 2.0
(10.1) (8.4) (8.4)
7.2 6.0 6.0
2.9 2.4 2.4
20.0 20.0
-
10.0
_
-
16.8
20.0 20.0 20.0
49.1 47.6 37.6
0
2
2
(8
6
2
30
16
10
20
10
.0
.0
.4)
.0
.4
.0
.8
-
.0
-
-
.0
.0
-------
following list gives the sources and grades for the formu-
lation components of Table 3.
Component Source Specifications
Carboxymethyl-
cellulose Hercules Inc. Type 7LT
Cocodiethanolamide Stepan Chemical Co. Ninol 128
extra
Sodium silicate Philadelphia Quartz Solution,
Co. star grade
Sodium acetate Celanese Chemical Co. Technical
(also B&A) Anhyd,
reagent
Trisodium Nitrilo-
triacetate Hampshire Chemical Co. NTA Na^-H-O
Sodium carbonate B&A Anhyd, reagent
Sodium chloride B&A Crystals,
reagent
Sodium sulfate B&A Anhyd, reagent
Sodium citrate B&A Crystals,
reagent
Linear Alkyl-
benzenesulfonate Conoco Slurry, C560
The sodium silicate solution and LAS slurry were used in
quantities which accommodated for their analyses to yield
the active ingredient concentrations shown in Table 3. The
nitrilotriacetate concentrations shown in Table 3 are
exclusive of the water of hydration (16.8% NTA Nao = 18.0%
NTA Na3-H20) .
It is seen that all of our Test Formulations contain
carboxymethylcellulose (CMC) , cocodiethanolarru.de and
sodium silicate. In order to accommodate for some loss in
soil-suspending properties due to the elimination of
phosphate, the levels of CMC are higher than those usually
employed which is also true in most cases for sodium
silicate. The surfactant concentration is at the high of
the normal use level, while the foam stabilizer, coco-
diethanolamide, is present at a normal concentration. Each
17
-------
formulation was tested in waters of 50, 135 and 300 ppm
hardness. The 50 ppm water was prepared from calcium and
magnesium chlorides using distilled water. Since Chicago
tap water possesses an approximate hardness of 135 ppm,
it was used directly for this level. The 300 ppm water
was prepared by adding calcium and magnesium chlorides to
Chicago tap water.
Test Results and Discussion
In considering the data and discussions which follow, it
must be kept in mind that the previously described
detergency evaluation procedure was employed as a tool to
aid in developing and evaluating a detergent. The
efficiency and economics of this test method make it one
of the best choices for our work.
Graphic form of the data is presented in the appendix
showing four-point detergency curve composites which
include the AHAM-2A and commercial product detergency
curves for the batch of cloth on which testing was
performed. The results of testing are interpreted and
discussed on a comparative basis using the commercial
brand and AHAM-2A as internal reference curves.
In comparing the results of our detergency screening
(graphs 2 through 46/ appended), it is seen that the
AHAM-2A formulation is quite inferior to the commercial
brand tested. In fact, superiority to AHAM-2A was readily
achieved by a number of formulations at the different
hardness levels. The most desirable detergency curve
characteristics are best illustrated by those obtained
from the commercial brand detergent where the low concen-
tration (0.1%) cleaning ability is rather good with a near
maximum cleaning ability being attained in the mid-concen-
tration region of 0.25%. Further significant increases in
formulation concentration (to 0.5%) produces only a
nominal improvement in cleaning properties. Surfactant
IIIA showed very poor detergent properties and was
eliminated as a candidate at an early stage in testing.
Surfactant IB2 was consistently inferior to its homolog,
IB1 and was therefore eliminated from consideration at a
somewhat later stage.
The composition of Test Formulation A allowed for
evaluation of the surfactants' cleaning abilities in
combination with some common builders and served as a
backbone in testing other candidate components. To augment
the loss in soil anti-redeposition properties created by
the elimination of phosphates, the carboxymethylcellulose
and silicate concentrations of TF A are at higher levels
than those normally employed. The behavior of LAS (as
18
-------
combined in TF A) is typical for surfactants adversely
affected by water hardness (Graphs 2-4). Whereas it
displays the best cleaning ability in soft water (50 ppm),
its efficiency in hard water drops Considerably more than
that observed for the phosphate-containing standards.
Irrespective of concentration behavior, TF A-LAS still
attains maximum detergencies which are among the best for
the Formulation A series. While no other surfactant "A"
formulation approaches LAS at 50 ppm, on the basis of
overall behavior, surfactant II exhibits equivalency to
LAS at 135 ppm while IB1 (and IIIA which was later dropped)
is superior to LAS at the initial and mid-region concen-
trations in hard water (300 ppm).
A further increase in silicate from the 10.1% level in TF A
to 14.1% in TF G (Graphs 20-22) was detrimental to cleaning
in soft water but generally enhanced the detergencies in
the harder waters. This improvement was pronounced in the
case of surfactant II at 135 ppm where the cleaning ability
of TF G-II was equivalent to the brand detergent in the
range of 0.28-0.5%. Although the cleaning by TF G-IA in
135 and 300 ppm water at 0.1% concentration was at a fair
level, the remaining overall detergency was only equivalent
to the LAS-containing formulation.
Formulations H and I (Graphs 23-28) are of the same basic
composition as "A" but, in addition, contain 10% of sodium
chloride and sodium sulfate, respectively. These "filler"
ingredients were used in this manner to make sure that
they presented no unexpected incompatibilities with the
surfactants. It should be noted that the TF I series was
screened on a batch of soiled cloth which possessed cleaning
characteristics different than that used for Formulations
"A" through "H". (This exemplifies the need for running
reference standards on cloths which possess different
cleaning characteristics.) While both chemicals slightly
reduced the effectiveness of LAS in soft water, sodium
sulfate (TF I) imparted a small improvement to the IA
containing formula; additionally, TF H and TF I shows a
drop in effectiveness at higher concentration, thus
creating a maximum in the detergency curves. In the case
of the sulfate formulation this latter characteristic is
present to a somewhat lesser degree at 135 ppm but does not
exist in 300 ppm wash water. On the other hand, the
sodium chloride formulation ("H") loses this characteristic
at 135 ppm hardness. Specifically, compounds II, IA and
LAS behaved best with sodium chloride in 135 ppm water
while sodium sulfate was better for surfactants IB1 and IA
at 300 ppm. In both of the above situations, the formu-
lations were superior to AHAM and approximated the results
obtained with the commercial brand. At this point then,
it was apparent that surfactants IA and IB1 were capable of
functioning better than LAS in hard water (300 ppm) .
19
-------
Sodium carbonate and sodium acetate were investigated as
possible alkaline builders to help replace the alkalinity
lost by the elimination of phosphate. Addition of 40%
sodium carbonate to TF A supplied Formulation C
(Graphs 8-10). The 40% concentration of sodium carbonate
was such that the calcium carbonate solubility constant
(KSp) was exceeded at all test levels. At 50 ppm hardness,
the carbonate generally improved the performance of
surfactants IA, IB1 and IB2 to a point where they were
equal to AHAM in the 0.3% concentration region; although
TF C-LAS did not possess as good a cleaning power at 0.25%
as its TF A analog, the detergency curve showed a steadily
increasing response to concentration, reaching the same
maximum but at the 0.5% level. In harder waters, carbonate
was detrimental to the cleaning ability of surfactant II,
but significantly improved the effectiveness of IA at
135 ppm and LAS at 300 ppm. Of significant value is the
fact that sodium carbonate improved the detergency of all
the surfactants at the 0.1% formulation level in water of
300 ppm hardness.
The base, sodium acetate, was added to TF A at the 30%
level to yield Test Formulation E (Graphs 14-16). While
this move did not change the soft water detergencies of LAS
and II, those of IA and IB1 were significantly improved.
The net result was that IA, IB1, IB2 and II were roughly
comparable to each other (approximating that of AHAM) while
LAS was significantly better in the normal use region of
0.25% but dropped appreciably at higher concentration.
Except for LAS, the use of sodium acetate greatly improved
the cleaning levels at 0.1% for all members of the series
over the entire range of water hardness. Cleaning results
in moderately hard and hard water were excellent as
compared to TF A. The best performer in 135 ppm water was
surfactant II whose effectiveness is equivalent to the
commercial product at 0.25% and above; though the effects
of IA and IB1 were improved considerably, neither was
superior to the LAS-containing formula. The results in
hard water were the most dramatic with E-IB1 and E-ll
outperforming E-LAS while approximating the cleaning
ability of the brand tested. Virtually all members of the
TF E series surpassed the ability of AHAM at 135 and
300 ppm.
In seeking a complementary substitute for the hard ion
effects of phosphate/ trisodium nitrilotriacetate (NTA)
and sodium citrate were screened for their chelating value
in detergents. In addition to the composition of Formu-
lation A, Test Formulation F contains 16.8% of NTA (Graphs
17-19). At 50 ppm the effect of NTA was to raise the
effectiveness and improve the general curve characteristics
for all members of the series. (The maximum cleaning
ability of the LAS formulation was actually less than A-LAS
but the general features of the data curve showed
20
-------
improvement.) In this case IA, II and LAS were almost
equivalent and about equal to AHAM while IB1 (and IB2) was
of somewhat reduced effectiveness. Performance by the "F"
series in Chicago water was somewhat disappointing where
the overall tendency was to reduce detergency characteris-
tics. This was especially true for LAS. Thus, the
effects of adding 16.8% of NTA were mixed. At 300 ppm, the
top cleaning levels were increased in most instances but
maxima appeared in the detergency curves as the cleaning
ability dropped off at the higher concentration.
The results with Test Formulation L, containing 16.8%
sodium citrate, were very poor at the 50 and 135 ppm hard-
ness levels (Graphs 35-37). In all of these cases the
cleaning abilities were drastically curtailed. In water
of 300 ppm hardness, detergency levels were better than
TF A in the mid-range of concentration, being roughly
equivalent to the NTA-containing series, but the effective-
ness was reduced at increased concentration.
The relative effects obtained by varying the components
as discussed above are presented in Table 4.
The data obtained with Formulations "D" (Graphs 11-13) are
the result of drastically reducing the silicate content of
"E" to 2.8% while Formulations in the "M" series are derived
from a simultaneous acetate and moderate silicate reduction.
The results of screening for TF D and M (Graphs 11-13 and
38-40 respectively) will be discussed in terms of compari-
son to the TF E series which was superior to the A formu-
lations. In comparing the detergency curves of Test
Formulations D and E to those of "M" we must consider the
fact that the soiled cloth used for the testing of "M"
possessed different cleaning characteristics. Thus, all
comparisons between the former and latter formulations must
be made with respect to the reference standards ("Brand"
and AHAM) .
A drastic decrease in the silicate content of "E" to 2.8%
(from 10.1%) gave the TF D series. In soft water, the
only significant effect was an increase in the cleaning
ability of the II containing formula. In Chicago water
(135 ppm), none of the surfactant-D formulations showed
any change as compared to the "E" analogs. There were
also no significant differences between the two formu-
lations at the 300 ppm hardness level.
As compared to the Formulation E series, the "M" series
possessed only a slight silicate reduction, being 8.4%,
while sodium acetate has been reduced to 20% (from 30%).
All members of the TF M series were poorer than "E" at the
50 ppm level. M-LAS, IA and II showed good performances in
Chicago water, being equal to, or possibly better than the
21
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Table 4
INDIVIDUAL EFFECTS9 OF VARIOUS BUILDERS AND ADDITIVESb/C
Sodium Sodium Sodium Sodium Sodium Trisodium Trisodium
Silicate Chloride Sulfate Carbonate Acetate NTA Citrate
Surfactant Hardness (G) (H) (I) (C) (E) (F) (L)
LAS 50 ---(+) -
135
300
IA 50
135
300
M IB1 50
10 135
300
II 50
135
300
aOn a comparative basis to the "A" Formulation which contains the same surfactant.
Blank space indicates "no effect".
°Parenthesized effects indicate a questionable result which could only be derived from one
facet of the curve analysis.
-------
brand used for reference; while M-LAS and II reached
higher cleaning levels, they dropped in effectiveness at
higher concentration, creating the condition of a maximum
in their detergency curves. In the hardest water,
reduction of acetate was highly detrimental to the IB1 and
II containing "M" formulations. It should be noted here
that the detergency curve of M-II at 300 ppm does not
reach a discernible inflection over the range of concen-
tration but rises steadily to attain a good detergency at
0.5% concentration.
No one member of the ten series of compositions discussed
to this point shows an overall superiority. Thus, the
best performers in soft water are apparently D-II and
E-LAS. The cleaning ability of these formulations at the
0.25 - 0.3% concentration level approximates that of the
reference brand and is far superior to AHAM. While their
effectiveness tapers off at higher concentration, they are
equal to each other and on a par with AHAM. At a 0.1%
formulation concentration E-LAS performs poorly, being
well below AHAM while D-II is equivalent to AHAM at this
concentration. Choosing the best performers in water of
135 ppm hardness at this point is not an easy decision.
The best results in the normally used concentration region
of 0.25% were obtained with M-LAS which was superior to the
reference brand at this point. Use of M-LAS at higher
concentration showed a decrease in effectiveness from the
maximum at 0.3%, dropping somewhat below the commercial
product. At low concentration, its effectiveness was not
very good although it was on a par with AHAM. The
performance of M-II was very similar to M-LAS in Chicago
water, its low concentration effectiveness being somewhat
higher with maximum cleaning at 0.3% being somewhat
inferior to M-LAS. While almost all "D" formulations and
some "E" formulations were quite good, the best overall
performer in moderately hard water seems to be M-IA; its
low concentration effectiveness was the best and, while it
did not possess the best cleaning ability at the 0.3% level,
it was equivalent to the "brand" at this point; as opposed
to a decreased detergency at higher concentration, it
improved slightly, remaining roughly equivalent to the
commercial brand. All members of the D, E and M series
performed better than AHAM at 300 ppm hardness. Up to the
highest concentration, M-IA, which appears to be the best
at 300 ppm, performed better than any other member of the
M series. At high concentration M-LAS was somewhat better.
D-II, D-LAS, E-IB1 and E-li all possessed detergency
properties which were about equivalent and on a par with
the "brand" detergent.
23
-------
The formulations discussed in the following dialogue are
the result of combining the various additives whose
functions help to replace those lost by the elimination of
phosphate.
A slight reduction in the silicate content of "A" as well
as the inclusion of 20% sodium acetate and 10% sodium
carbonate leads to Formulation N (Graphs 41-43). All
members of this series showed poor detergencies in soft
water. In Chicago water, N-LAS and N-II possessed good
cleaning ability up to 0.25% concentration which dropped
sharply at higher concentration. This was also true of
N-IA and N-IB1 in hard water where N-LAS showed good
detergency only at the 0.25% concentration level. Overall,
the Formulation "N" series showed no improvement over the
best of those already discussed.
Formulations J, K and O (Graphs 29-34 and 44-46) are
similar inasmuch as they all possess sodium acetate and
NTA. Formulation J is obtained by the addition of 16.8%
of NTA to the 30% acetate formulation ("E") while "K" is
the same as "J" except that the acetate concentration has
been reduced. Multiple comparisons of the data lead to a
number of conclusions. By comparing the detergencies of
Formulations J and K it is evident that in soft and
moderately hard water the reduction of acetate in these NTA-
containing formulas is detrimental to the cleaning ability,
irrespective of the surfactant used. An additional favor-
able point for the use of higher acetate concentration in
soft water is the fact that there was no drop in detergency
at higher concentrations. In all cases except one, the
results of acetate reduction showed no change in hard
water; the lone exception was the J-IA, K-IA comparison
which showed improvement upon reduction of the acetate.
At 50 ppm hardness, the addition of 10% sodium chloride to
TF J (giving TF O) reduced the effectiveness of the LAS-
containing member and improved the formulation which
contained IA. In water of 135 ppm hardness, the sodium
chloride improved the effectiveness of the member
containing surfactant IA and was detrimental to the
surfactant II composition. This was also true at 300 ppm
hardness. Overall, while the use of sodium chloride in an
acetate-NTA composition had no pronounced constant
effect, it was not detrimental to the formulation.
In contrast to the soft water cleaning of D-II and E-LAS,
which showed good detergency at 0.25% but dropped in
efficiency at higher concentration, O-IA showed a steady
increase in detergency with increasing concentration so
that its cleaning ability approximated that of the "brand"
at the highest concentration. On the other hand, the "O"
Formulations were not as good as the "M" series in an
24
-------
overall comparison even though O-LAS and IA possessed the
same high concentration cleaning ability in Chicago water.
The last formulation to be considered is "B" (Graphs 5-7)
which contains 22% acetate in combination with 15% sodium
sulfate. All members of this series tested rather poorly
in soft water while the surfactant II-containing
composition performed well in Chicago tap water. The hard
water performance of B-IA and LAS were rather respectable
while B-II was a poor performer at this hardness.
In general, the pH of the wash water which contained low
concentrations of the phosphate-free formulations was
somewhat deficient, being close to neutral instead of the
desired 8-10.
25
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SECTION V
ACKNOWLEDGMENTS
This project was carried out by the IIT Research Institute
under Contract No. 14-12-575 for the Federal Water Quality
Administration.
The concept of using potentially "self-chelating"
surfactants in phosphate-free detergent formulations was
fostered by Dr. Warner M. Linfield, Manager, Organic
Chemistry Research Section, IIT Research Institute, while
a number of additional formulation ideas were contributed
by Dr. Karl A. Roseman, Research Chemist.
IITRI personnel who directly participated in this project
include H. DeYoung, L. Hytry, M. Gould and C. Wetter of
the Organic Chemistry Research Section as well as
S. Miller and S. Vana of IITRI's Life Sciences Division.
Special thanks are given to Dr. C. C. Harlin, Jr., Chief
of the Water Quality Control Research Program, Robert S.
Kerr Water Research Center, FWQA, whose suggestions and
interest provided guidance in the evaluation of our work.
This project was designed, operated and administered by
the IIT Research Institute; Dr. Warner M. Linfield was
Project Director and Dr. Karl A. Roseman was Project
Leader.
27
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SECTION VI
REFERENCES
1. Subcommittee on Biodegradation Test Methods of the
Soap and Detergent Association, J. Am. Oil Chemists'
Soc., 42, (11) 986 (1965).
2. Am. Public Health Assoc., Am. Water Works Assoc.,
Water Pollution Control Fed., Standard Methods for
the Examination of Water and Waste Water, p. 296,
Boyd Printing Co. Inc., Albany, N. Y. (1965).
3. W. M. Linfield, E. Jungermann and C. J. Sherrill,
J. Am. Oil Chemists' Soc., 39, 47 (1962).
4. M. E. Ginn, G. A. Davis and E. Jungermann, J. Am. Oil
Chemists' Soc., 43_, 317 (1966).
5. Osaka Shiritsu Daigaku Kaseigakubu-Kiyo, 12, 29
(1964); CA, 63:13582b.
6. R. C. Davis, Soap & Chem. Specialties, 39, 47 (1963).
7. A. M. Schwartz and J. Berch, Soap & Chem. Specialties,
39_, 78 (1963) .
8. G. W. Hedrick, W. M. Linfield and T. J. Eaton, Ind.
and Eng. Chem., 44, (2) 314 (1952).
9. U. S. Patent No. 2,658,072, November 3, 1953.
10. C. D. Hurd and J. R. Ferraro, J. Org. Chem., 16, 1639
(1951) .
29
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SECTION VII
APPENDIX
Graph 1, page 32: Reference calibrations for surfactant-
methylene blue complexes which were
used in the presumptive biodegradability
test.
Graphs 2-46, pages 33-77: Composite detergency curves for
Formulations A through O as
obtained using the U. S. Testing
Co. standard soiled cotton
cloth.
Synthetic Procedures and Analyses -for the Surfactants
Surfactant IA: Sodium dodecylbenzenesulfonamidoethyl
sulfate
Surfactant IB1; Sodium dodecylbenzenesulfonamidoethyl-
sulfonate (
Surfactant IB2: Sodium N-methyl-dodecylbenzenesulfonamido-
ethylsulfonate (
Surfactant II: Methyl 3-dodecylbenzoyl-3( 2) -( sodium
sulfonato)propionate (CHC
Surfactant IIIA; Sodium dodecylaminoethanesulfonate
Surfactant IIIB; Sodium N-hydroxy ethyl -2 -dodecylamino-
ethanesulfonate (CH
Surfactant IVA; Dodecyl 3- (sodium levulinate) sulfone
31
-------
0.24
u>
to
Optical Density (Corr.)
0.20
0.16
0
-10
30
50
70
90
LAS
0.000
0.012
0.069
0.141
0.166
0.212
IA
0.000
0.010
0.041
0.070
0.098
0.126
IB1
0.000
0.010
0.043
0.076
0.113
0.149
IB2
0.000
0.007
0.032
0.066
0.098
0.127
II
0.000
0.016
0.038
0.072
0.106
0.142
4J
-H
CO
P 0.12
(U
u
•H
-P
<^0.08
0.04
LAS
(Commercial
Sample)
IB1
II
IA
IB2
Bausch & Lomb Spectronic 20
Wavelength = 652
(Blue Phototube)
10
20 30 40 50 60 70
Total jug Surfactant/Aliquot Extracted
80
90
100
Graph 1. REFERENCE CALIBRATIONS FOR SURFACTANT-METHYLENE BLUE COMPLEX
-------
UJ
OJ
36
32
28
(D
>
g
0)
r-f
•H
O
I20
u
-------
UJ
12 —
0.1
0.2
0.3 0.4
% Formulation in Wash Water
0.5
Graph 3. DETERGENCIES OF TEST FORMULATIONS "A" AT 135 PPM HARDNESS
-------
36
01
to
I
•H
o
32
28
24
4J
g 2°
M
(U
04
16
12
Brand
LAS
IIIA
IB1
IB2
IA
II
I
0.1
0.2
0.3 0.4
% Formulation in Wash Water
0.5
Graph 4. DETERGENCIES OF TEST FORMULATIONS "A" AT 300 PPM -HARDNESS
-------
u>
12 —
0.1
0.3 0.4
% Formulation in Wash Water
0.5
0.2
Graph 5. DETERGENCIES OF TEST FORMULATIONS "B" AT 50 PPM HARDNESS
-------
ro
>
g
0)
36
32
28
24
•H
o
CO
g 20
u
M
(U
16
12
Bran
I
II
LAS
IA
IIIA
IB1 and IB2
0.1
0.2
0.3 0.4
% Formulation in Wash Water
0.5
Graph 6. DfiTERGENCIES OF TEST FORMULATIONS "B" AT 135 PPM HARDNESS
-------
36
u>
00
32
28
24
•H
O
co
c 20
0)
u
M
0)
16
12
0.1
Brand
0.2
I
0.3 0.4
% Formulation in Wash Water
IIIA
0.5
Graph 7. DETERGENCIES OF TEST FORMULATIONS "B" AT 300 PPM HARDNESS
-------
U)
VO
36
32
28
24
o
co
4J
g 20
M
0)
04
16
12
0.1
Brand
I
0.2
IIIA
0.3 0.4
% Formulation in Wash Water
0.5
Graph 8. DETERGENCIES OF TEST FORMULATIONS "C" AT 50 PPM HARDNESS
-------
12 —
0.1
0.2
0.3 0.4
% Formulation in Wash Water
0.5
Graph 9. DETERGENCIES OF TEST FORMULATIONS "C" AT 135 PPM HARDNESS
-------
12 —
0.1
Graph 10,
0.3 0.4 0.5
% Formulation in Wash Water
DETERGENCIES OP TEST FORMULATIONS "C" AT 300 PPM HARDNESS
-------
IA
II
LAS
IB1 and IB2
0.2
0.5
Graph 11.
0.3 0.4
% Formulation in Wash Water
DETERGENCIES OF TEST FORMULATIONS "D" AT 50 PPM HARDNESS
-------
OJ
36
32 —
IB1
IA + IB2 + II
LAS
16
12
IIIA
0.1 0.2 0.3 0.4 0.5
% Formulation in Wash Water
Graph 12. DETERGENCIES OF TEST FORMULATIONS "D" AT 135 PPM HARDNESS
-------
36
32
28
0)
•H
O
CO
24
-P
S 20
u
n
0)
16
12
Brand
IIIA
I
0.1
0.2
0.3 0.4
% Formulation in Wash Water
0.5
Graph 13. DETERGENCIES OF TEST FORMULATIONS "D" AT 300 PPM HARDNESS
-------
en
12 —
0.1
Graph 14.
0.3 0.4 0.5
% Formulation in Wash Water
DETERGENCIES OF TEST FORMULATIONS "E" AT 50 PPM HARDNESS
-------
0.2
0.5
Graph 15.
0.3 0.4
% Formulation in Wash Water
DETERGENCIES OF TEST FORMULATIONS "E" AT 135 PPM HARDNESS
-------
36
32
H
> 28
a)
•H
o 24
to
(U
O
04
20
16
12
Brand
I
I
0.1
0.2
0.5
0.3 0.4
% Formulation in Wash Water
Graph 16. DETERGENCIES OF TEST FORMULATIONS "E" AT 300 PPM HARDNESS
-------
36
oo
ro
>
0)
•H
O
32
28
24
§ 20
M
0)
04
16
12
Bram
I
0.1
0.2
0.5
0.3 0.4
% Formulation in Wash Water
Graph 17. DETERGENCIES OF TEST FORMULATIONS "F" AT 50 PPM HARDNESS
-------
VO
LAS
IB1 and IB2
16
12
I
I
0.1
0.2
Graph 18.
0.5
0.3 0.4
% Formulation in Wash Water
DETERGENCIES OF TEST FORMULATIONS "F" AT 135 PPM HARDNESS
-------
en
O
12 —
0.1
Graph 19.
0.3 0.4 0.5
% Formulation in Wash Water
DETERGENCIES OF TEST FORMULATIONS "P" AT 300 PPM HARDNESS
-------
36
32
28
ro
>
i
0)
24
•H
O
CO
§20
n
0)
04
16
12
Branc
IB1
I
I
I
0.1
0.2
0.5
0.3 0.4
% Formulation in Wash Water
Graph 20. DETERGENCIES OF TEST FORMULATIONS "G" AT 50 PPM HARDNESS
-------
Ul
to
36,
32
28
to
>
Q
•rl
o
co
24
-P
S 20
u
M
(U
16
12
.1
I
0.2
0.3 0.4
% Formulation in Wash Water
0.5
Graph 21. DETERGENCIES OF TEST FORMULATIONS "G" AT 135 PPM HARDNESS
-------
Ul
IU
>
i
QJ
O
CO
32
28
24
-P
§ 20
M
0)
CU
16
12
Brand
I
0.1
0.2
I
I
0.5
0.3 0.4
% Formulation in Wash Water
Graph 22. DETERGENCIES OP TEST FORMULATIONS "G" AT 300 PPM HARDNESS
-------
Ul
*»•
IB1
12 —
1 1 1 1
3.1 0.2 0.3 0.4
0.5
% Formulation in Wash Water
Graph 23. DETERGENCIES OF TEST FORMULATIONS "H" AT 50 PPM HARDNESS
-------
en
ui
0.5
Graph 24.
0.2 0.3 0.4
% Formulation in Wash Water
DETERGENCIES OF TEST FORMULATIONS "H" AT 135 PPM.HARDNESS
-------
en
12 —
0.1
0.2
0.3 0.4
% Formulation in Wash Water
0.5
Graph 25. DETERGENCIES OP FORMULATIONS "H" AT 300 PPM HARDNESS
-------
en .
-j
36
32
(D
>
•H
o
28
24
-P
§ 20
M
(U
16
12
0.1
—-^. IA
LAS
IB1
II
0.2
0.5
Graph 26.
0.3 0.4
% Formulation in Wash Water
DETERGENCIES OF FORMULATIONS "I" AT 50 PPM HARDNESS
-------
(Jl
00
0.2
0.5
Graph 27.
0.3 0.4
% Formulation in Wash Water
DETERGENCIES OF FORMULATIONS "I" AT 135 PPM HARDNESS
-------
Ul
vD
ro
>
•H
O
CO
36
32
28
24
-p
c
0)
o 20
0)
16
12
Brand
I
0.1
0.2
0.5
Graph 28.
0.3 0.4
% Formulation in Wash Water
DETERGENCIES OF FORMULATIONS "I" AT 300 PPM HARDNESS
-------
36
32
H 28
10
>
w 24
rH
•H
O
CO
-P
S 20
u
M
0)
04
16
12
Brand
LAS and II
0.1
0.2
0.3 0.4
% Formulation in Wash Water
0.5
Graph 29. DETERGENCIES OF FORMULATIONS "J" AT 50 PPM HARDNESS
-------
0.2
0.3 0.4
% Formulation in Wash Water
0.5
Graph 30. DETERGENCIES OP FORMULATIONS "J" AT 135 PPM HARDNESS
-------
0.2
0.5
Graph 31.
0.3 0.4
% Formulation in Wash Water
DETERGENCIES OF FORMULATIONS "J" AT 300 PPM HARDNESS
-------
u>
ro
36
32
28
H 0/|
•H 24
-P
(U
^20
0)
16
12
0.1
Brand
II and LAS
^^t^* IA and
0.2
0.5
0.3 0.4
% Formulation in Wash Water
Graph 32. DETERGENCIES OF FORMULATIONS "K" AT 50 PPM HARDNESS
-------
36
32
•H
0
CO
28
24
-P
§ 20
s-i
-------
en
en
36
32
m
0)
•H
O
28
24
4J
C
-------
36
32
g 28
-------
12
0.1 0.2 0.3 0.4 0.5
% Formulation in Wash Water
Graph 36. DETERGENCIES OF FORMULATIONS "L" AT 135 PPM HARDNESS
-------
36
00
32
28
1
05
o
tn
24
a 20
16
12
Brand
II
LAS
IA
IB1
I
I
I
I
0.1
0.2
0.5
Graph 37.
0.3 0.4
% Formulation in Wash Water
DETERGENCIES OP FORMULATIONS "L" AT 300 PPM HARDNESS
-------
VO
0.3 0.4
% Formulation in Wash Water
0. 5
Graph 38. DETERGENCIES OF FORMULATIONS "M" AT 50 PPM HARDNESS
-------
0.1
0.3 0.4
% Formulation in Wash Water
0.5
Graph 39. DETERGENCIES OF FORMULATIONS "M" AT 135 PPM HARDNESS
-------
36
32
28
o
tf
o 24
CO
-P
c
0)
a 20
0)
16
12
I
I
I
0.1
0.2
0.5
0.3 0.4
% Formulation in Wash Water
Graph 40. DETERGENCIES OF FORMULATIONS "M" AT 300 PPM HARDNESS
-------
36
32
28
•H 24
-P
£
0)
16
12
Brand
I
0.1
0.2
0.5
Graph 41.
0.3 0.4
% Formulation in Wash .Water
DETERGENCIES OF FORMULATIONS "N" AT 50 PPM HARDNESS
-------
u>
0.1
Q.2
0.5
Graph 42.
0.3 0.4
% Formulation in Wash Water
DETERGENCIES OF FORMULATIONS "N" AT 135 PPM HARDNESS
-------
>
a)
-H
o
CO
36
32
28
24
-P
0)
o 20
0)
Pu
16
12
Brand
II
LAS and IA
IB1
0.1
0.2
0.3 0.4
% Formulation in Wash Water
0.5
Graph 43. DETERGENCIES OF FORMULATIONS "N" AT 300 PPM HARDNESS
-------
•vj
en
•H
o
CO
36
32
28
24
8 20
M
(U
16
12
071
Brand
0.2
0.5
Graph 44.
0.3 0.4
% Formulation in Wash Water
DETERGENCIES OF FORMULATIONS "0" AT 50 PPM HARDNESS
-------
0.2
0.3 0.4
% Formulation in Wash Water
0.5
Graph 45. DETERGENCIES OF FORMULATIONS "0" AT 135 PPM HARDNESS
-------
12
0.1 0.2 0.3 0.4 0.5
% Formulation in Wash Water
Graph 46. DETERGENCIES OF FORMULATIONS "0" AT 300 PPM HARDNESS
-------
Synthetic Procedures and Analyses for the Surfactants
Surfactant IA: Sodium dodecylbenzenesulfonamidoethyl
sulfate (C, 0H_t.C,.H.SO_NHCH_CH-OSO-Na)
L2 2t> o 4 2 22 3
2C1SO H NH CH CH7OSO H
CHCH ^ CHCHS°C1
'12"25 6"5 ' 12"25"6"4" 2 * Base
a k
C12H25C6H4S02NHCH2CH2OS03Na
IA
Dodecylbenzenesulfonyl chloride (b) was used as a crude
mixture in 1,2-dichloroethane. Thus 24.6 g (0.1 m) of
dried dodecylbenzene (a) was mixed with 33 ml of dried
1,2-dichloroethane in a 3-neck flask which was equipped
with an internal thermometer, magnetic stirring bar, gas
equilibrating dropping funnel and a reflux condenser topped
with an outlet tube and connected to a gas trap. The
chlorosulfonic acid, 23.3 g (0.2 m) was added slowly with
cooling and stirring while maintaining an internal
temperature range of 22-28°C. After addition was complete,
the amber solution was stirred at room temperature for two
hours and gentle aspiration was applied via the outlet
tube on the condenser to help remove the hydrogen chloride
and any unreacted chlorosulfonic acid. This crude mixture
was then used as is in the following procedure.
The above 1,2-dichloroethane solution of dodecylbenzene-
sulfonyl chloride (0.1 m) was slowly added to a mixture
containing 28.2 g (0.2 m) of aminoethyl hydrogen sulfate,
45 g of sodium bicarbonate and 50 ml of water. A pH of
7.5 - 8.0 was maintained by the addition of small amounts
of sodium bicarbonate when needed. The mixture was then
heated in a hot water bath for 2 hours with occasional
stirring, cooled and diluted with 600 ml of saturated
potassium chloride solution. The precipitated gelatinous
product was filtered by gravity and dried in a vacuum oven
at 50-60°C/13 torr. The somewhat gummy product was
extracted with boiling absolute methanol to yield 33.4 g
of product after removal of the methanol under reduced
pressure.
The spectral and physical properties of the isolated
product are in accord with the proposed structure. The
five aromatic protons of the starting alkylbenzene are not
greatly different in their chemical shifts and appear as a
"close" multiplet. centered at 432 Hz (PMR Spectrum No. 1).
On the other hand, the four aromatic protons of the para-
sulfonyl-alkylbenzene are best represented as an AA'XX1
78
-------
-J
\t>
i ......... i ........ i , . . I . , , . i i i ......... i ....
-------
spin system (Figure 1) and would be expected to show the
two areas of absorption which are seen in the spectrum of
the product (PMR Spectrum No. 2).
Figure 1
PROTON ASSIGNMENTS OF PARA SULFONYL-ALKYLBENZENE
Moving upfield in the spectrum (towards the tms peak) the
increased spectrum amplitude sweep ("B") shows the region
of absorption of the sulfonamido methylene protons
(-SO2NH-CHo) at 190 Hz and that of the sulfate methylene
(-CH2OSO3-f at 250 Hz. The hydrocarbon protons appear in
the region of 50-100 Hz with the phenylmethylene
(-CH2-C6H4-) being visible at 150 Hz. Although the proton
integration is quite acceptable for the assigned structure,
the normally broad -NH signal could not be accounted for.
The infrared spectrum of this material shows the symmetric
and asymmetric SO2 stretching absorptions of sulfonamide
at 8.62 and 7.55M (1160 and 1325 cm-1), respectively. The
probable symmetric and asymmetric SO2 stretching modes of
sulfate are seen at 8.85 and 6.82/u (1130 and 1466 cm-1).
The N-H stretching signal of sulfonamido appears at 3.17//.
(3155 cm-1).
The dried product was titrated with a standard cation
(Rohm & Haas1 Hyamine 1622) to determine its anion content.
Pure product requires a titre of 2.12 meq/g, whereas sodium
dodecylbenzenesulfonate (the most probable by-product from
simple hydrolysis of the sulfonyl chloride) possesses a
theoretical titration value of 2.87 meq/g. The found titre
was 2.24 meq/g. As determined from the following Table,
the product could contain 86% of the desired sulfate, IA.
80
-------
00
-------
CALCULATED CATIONIC TITRATION VALUES FOR MIXTURES
SODIUM DODECYLBENZENESULFONAMIDOETHYL SULFATE (IA) AND
SODIUM DODECYLBENZENESULFONATE (LAS)
Grams
of IA
1.0
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0.0
Meq
of I
2.12
1.91
1.70
1.48
1.27
1.06
0.85
0.64
0.42
0.21
0.00
Grams
of LAS
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
Meq
of LAS
0.00
0.29
0.57
0.86
1.15
1.44
1.72
2.01
2.30
2.59
2.87
Total meq/g
of Mixture
2.12
2.20
2.27
2.34
2.42
2.50
2.57
2.65
2.72
2.80
2.87
Surfactant IB1; Sodium dodecylbenzenesulfonamidoethyl
sulf onate (
2C1SO.H NH CH CH SO H
C12H25C6H5 - -* C12H25C6H4S°2C1 Base >
a b
Cn _Hot.C,.H .SO_NHCH0CH_SO_Na
±2 2.3 D 4 z 2 2 J
IB1
The dodecylbenzenesulfonyl chloride (b) solution was
prepared as described previously. A 0.4 m quantity of this
solution was slowly added, at room temperature, to a
mixture containing 65.6 g (0.52 m) of taurine
(H2NCH2CH2SO3H) , 125 g of sodium bicarbonate and 175 ml of
water. An additional amount of sodium bicarbonate was
added during the course of the addition to maintain the pH
between 7 and 8. After addition was completed, the
reaction mixture was heated by a boiling water bath for
2 hours with occasional stirring. The mixture was then
brought to a boil by direct heating and 1500 ml of
saturated potassium chloride solution was added. After
cooling, the gelatinous product was filtered by gravity,
82
-------
dried in a vacuum oven (50-60°C/13 torr) and the solid -was
extracted with 750 ml of boiling methanol. After removal
of the solvent under reduced pressure the material was
dried again in a vacuum oven.
Cationic titration for anion determination of this material
yielded a value of 2.28 meq/g. The theoretical value for
the sulfonamidoethylsulfonate (IB1) is 2.20 meq/g.
Consideration of the probable contamination by LAS by-
product leads to the titration values given in the following
Table for fraction combinations of product and LAS, where
it is seen that the product could be 88% of the desired
surfactant. Product isolated from other procedures
supplied a titre of 2.54 meq/g which indicated that 50%
of the product was LAS.
CALCULATED CATIONIC TITRATION VALUES FOR MIXTURES
OF SODIUM DODECYLBENZENESULFONAMIDOETHYLSULFONATE (IB1)
AND SODIUM DODECYLBENZENESULFONATE (LAS)
Grams
of IB1
1.0
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0.0
Meq
of IB1
2.20
1.98
1.76
1.54
1.32
1.10
0.88
0.66
0.44
0.22
0.00
Grams
of LAS
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
Meq
of LAS
0.00
0.29
0.57
0.86
1.15
1.44
1.72
2.01
2.30
2.59
2.87
Total meq/g
of Mixture
2.20
2.27
2.33
2.40
2.47
2.54
2.60
2.67
2.74
2.81
2.87
The disparate aromatic multiplets in PMR Spectrum No. 3
(464 and 423 Hz) again indicate sulfonation of the
aromatic nucleus. The area of absorption centered at
196 Hz is attributed to the combination of signals from
the sulfonamido methylene (-SO2NHCH2-) and sulfonato
methylene (-CH2s°3Na) protons. These signals should
integrate to four protons if the material were pure. The
fact that this area represents only three protons, with
respect to the overall spectrum, leads to the conclusion
83
-------
00
•/S^ riffiin II^'MM outr «M
^s^—~ «»..
-------
that the product contains 75% of the desired surfactant,
IB1, which is less than that indicated by the anion
determination.
Surfactant IB2; Sodium N-methyl-dodecylbenzenesulfonamido-
ethylsulfonate (CHCH
2C1SO H NH(CH_)CH9CH5SO H
~ Base
12H25C6H5 - ~* C12H25S02C1 -
C12H25S°2N^CH3)CH2CH2S°3Na
The solution of dodecylbenzenesulfonyl chloride (0.4 m)
was slowly added, at room temperature, to a mixture
containing 198.4 g of 65% aqueous sodium N-methyltaurate
(equivalent to 0.8 m N-methyltaurine, sodium salt) , 130 g
of sodium bicarbonate and 175 ml of water. During the
course of this addition 75 ml of dichloroethane and 100 ml
of water were added to maintain the fluidity of the
mixture so that magnetic stirring was effective. (No
additional sodium bicarbonate was required to maintain
the basicity of the reaction mixture.) After the addition,
the reaction mixture was heated with a hot water bath for
2 hours with occasional stirring. The mixture was then
heated to a boil and 150 ml of isopropyl alcohol was added.
After cooling in a separate ry funnel, the lower aqueous
layer was separated; the upper organic layer was stripped
of solvent under reduced pressure and the residue was
dried in a vacuum oven at 50-60°C/13 torr. The pale
yellow solid was extracted with 350 ml of hot methanol
yielding 125 g of material after removal of the methanol
and drying. Because the anion determination of this
material was an unsatisfactory 1.91 meq/g, the product
was then extracted with hot absolute ethanol. After
removal of the solvent and drying, the anion titre was
2.10 meq/g which is slightly lower than the theoretical
of 2.13 shown in the following Table.
85
-------
CALCULATED CATIONIC TITRATION VALUES FOR MIXTURES
OF SODIUM N-METHYL-DODECYLBENZENESULFONAMIDOETHYL-
SULFONATE (IB2) AND SODIUM DODECYLBENZENESULFONATE (LAS)
Grams
of IB2
1.0
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0.0
Meq
of IB2
2.13
1.92
1.70
1.49
1.28
1.06
0.85
0.64
0.43
0.21
0.00
Grams
of LAS
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
Meq
of LAS
0.00
0.29
0.57
0.86
1.15
1.44
1.72
2.01
2.30
2.59
2.87
Total meq/g
of Mixture
2.13
2.21
2.27
2.35
2.43
2.50
2.57
2.65
2.73
2.80
2.87
The PMR spectrum of this material (No. 4) did not corrobo-
rate this high purity. There is a significant signal at
434 Hz which is superposed on a portion of the sulfonated
alkylbenzene proton signals. This indicates the presence
of some unreacted dodecylbenzene. Consideration of the
integration in this region gives an 85% purity. However,
the integration ratio between the remaining signal areas
(132-230 Hz vs 40-120 Hz) substantiates only an 80% purity.
This material was used in formulation work but did not
show promise and was dropped as a candidate surfactant.
86
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00
-J
-------
Surfactant II; Methyl 3-dodecylbenzoyl-3(2)-(sodium
sulfonato)propionate8 (CHC
r H r H Maleic Anhyd.
U12n25°6rt5 Anhyd. A1C13
a_
CH3OH/H+ Reflux
Dichloroethane
NaHSO
II
The acrylic acid intermediate (b) was prepared as follows:
44 g (0.5 m) of maleic anhydride was mixed with 110 g of
dry dichloroethane in a 3-neck flask equipped with a thermo-
meter, magnetic stirrer, dropping funnel and a reflux
condenser which was topped with a drying tube. The
anhydrous aluminum chloride (105 g, 0.8 m) was added with
cooling and, after ten minutes of stirring, 123 g (0.5 m)
of dried dodecylbenzene was added while maintaining the
temperature below 15 °C. Additional solvent was added as
needed to keep the mixture free flowing. (Foaming is
minimized if the temperature is held below 11 °C) . After
stirring at 10-15 °C for 1/2 hour and at room temperature
for 3/4 of an hour, the viscous dark brown mixture was
poured into a beaker containing 450 g of ice, 50 ml of 66%
sulfuric acid and 15 ml of isopropyl alcohol. After
thorough mixing, the bright yellow mixture was allowed to
stand overnight and the upper, yellow, organic layer was
separated and washed twice with 70 ml portions of 66%
sulfuric acid which contained 10 ml of isopropyl alcohol,
making sure that sufficient time was allowed for complete
layering to take place. Finally, the organic layer was
washed with saturated sodium chloride solution and stripped
of solvent under reduced pressure, leaving a viscous amber
liquid. Basic titration of this material required 2.54
meq/g. The theoretical value for the acrylic acid inter-
mediate (b) is 2.69 meq/g.
The PMR spectrum of this material (PMR Spectrum No. 5) is
in excellent agreement with the assigned structure. The
signal at 628 Hz represents the carboxylic acid proton
while the signals between 400 and 500 Hz are the aromatic
and alkene protons. Expansion of this region (not shown)
and consideration of the effects of esterification in the
next step lead to the following specific assignments with
88
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CD
^
-------
reference to the structure shown on PMR Spectrum No. 5:
The signals at 489, 482 and 474 Hz are due to protons A,A1
and HM where the chemical shift of the A,A1 aromatic
protons is close to that of the HM alkene proton causing
overlap of multiplets; the doublets' centered at 443 and
435 Hz represent the XX1 aromatic protons; the peaks at
420 and 405 Hz are due to the alkene proton HB which shows
as a doublet due to (trans) coupling with its vinylic
neighbor HM; the broad, low intensity signal centered at
about 162 Hz is from the somewhat deshielded methylene
group which is directly bonded to the aromatic nucleus;
the broad based, high intensity signal at 73 Hz is due to
the remaining alkyl (hydrocarbon) portion of the molecule.
The overall integration (exclusive of the acid proton) is
quite satisfactory for the assigned structure. The sharp
signal appearing at 223 Hz is due to the presence of
residual 1,2-dichloroethane and, according to the integra-
tion, comprises about 4% of the sample.
The infrared spectrum (neat film) of the washed product was
also in good agreement with the assigned structure. The
C-H stretching mode appeared as a strong signal (ca. 3.5/u)
with a very broad, medium intensity base extending from
2.85M (3500 cm-1) to 4.17/z (2400 cm-1) and possessed maxima
which are typical of those expected for the carboxylic acid
O-H stretching mode. A high intensity peak at 5.85/i
(1709 cm"1) readily assumes the assignment of the acid
carbonyl (dimer) while that at 6.0/z (1667 cm"1) can be
correlated to the presence of an aryl a,p~unsaturated
ketone. Finally, a broad, high intensity signal at 7.75M
(1290 cm-1) (coupling of the O-H bending and -C-OH
stretching modes) also corroborates the presence of a
carboxylic acid.
Next, the unsaturated keto acid was esterified with
methanol. Thus, 19.2 g of methanol (0.6 m) and 10 ml of
concentrated sulfuric acid were added to a solution of the
above dry intermediate (b) in 100 ml of dry 1,2-dichloro-
ethane. The solution was heated at reflux for 3/4 of an
hour, the formed aqueous layer was separated and an
additional 12.8 g (0.4 m) of methanol and 6 ml of concen-
trated sulfuric acid were added. After refluxing for an
additional 1 1/2 hours the organic layer was separated and
the solvent was removed under reduced pressure. Titration
of the residual oil with standardized ethanolic potassium
hydroxide solution showed the acid content to be less than
4% (assuming that the only source for titre was from the
presence of unreacted starting material).
PMR Spectrum No. 6 shows the predictable changes which
would be caused by esterification of the acid (PMR
Spectrum No. 5). The reaction product showed an increased
chemical shift di-fference between the aromatic "A" protons
90
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-------
and the vinyl proton, HM/ giving complete separation of
these signals. The peaks at 481 and 472 Hz represent the
A and A1 protons which show essentially as a doublet due
to the ortho coupling with the X and X1 neighbors while the
absorptions at 484 and 469 are assigned to the HB vinylic
proton which is split by its (trans)vinylic neighbor, HM.
The signals centered at 442 and 436 Hz represent the aroma-
tic "X" protons and the singlets at 419 and 404 represent
the remaining H^ proton. Expansion of the aromatic and
alkene signals showed the following correlating coupling
constants: J^AXX A'X' ]_ = ®*^ Hz/ JHBM = 15.5 Hz and
•JHxx1 = 1.8 Hz while «JHAAi and «JHAXI(AIX) were not resolv-
able. The carboxylic acid proton absorption (-CC^H) of the
starting material is no longer present while a strong sig-
nal at 231 Hz now appears which is assigned as the carbo-
methoxy (-CC^CHj) protons. The low intensity signals just
upfield of this latter peak are probably due to residual
methanol and dichloroethane. The signal immediately
adjacent to the methoxy might be due to the presence of
some cis isomer.
The infrared spectrum (neat film) of this material showed
an almost complete loss of the broad, strong acid O-H
absorption in the region of 2.85-4.17M- The carbonyl
stretching peak at 5.75/u (1739 cm~l) shows the expected
shift for the formation of an ester while esterification
had little effect on the ketone carbonyl which appears at
5.95/i (1681 cm"-*-) . The appearance of a broad, medium
intensity signal at 8.55jU (1170 cm"-'-) is also indicative
of an ester when correlated to the band at 7.75^ (1290 cm~l)
which was also present for the starting material (symmetri-
cal and asymmetrical stretching of C-O-C, respectively).
Conversion of the acrylate (c) to the desired surfactant
(II) was accomplished by the addition of sodium bisulfite
across the double bond (Step 3). A Parr pressure reactor
was charged with 140 g (0.39 m) of the ester (c), 40.5 g
(0.39 m) of sodium bisulfite and 140 ml of water. The
mixture was heated in the sealed container with stirring
for 3 hours at 110-140°C; the pressure reaching a maximum
of 60 Ibs at 140°C. The yellow mixture was removed and
dried in a vacuum oven at 55°C/13 torr. The anion content
of this particular material was 1.99 meq/g as determined
by cationic titration. The theoretical value for
surfactant II is 2.16 meq/g, inferring ca. 90% purity.
(All other runs gave values higher than 1.99).
The infrared spectrum of this material possessed a strong
signal at 9.52/Li (1050 cm"1) which is readily attributed to
the symmetrical -SC>2 stretching mode of a sulfonate group.
The accompanying asymmetric stretching of -SC>2 would
appear in the region of the already present ester C-O-C
stretching region. Additionally, a low intensity signal
92
-------
which was present for the starting acrylate (c) at 6.1/u
(1639 cm-1) was no longer present in the bisulfite addition
product. The loss of this signal would be expected if it
were due to the -C=C- stretching mode of the alkene
functional group.
PMR Spectrum No. 7 pretty well verifies the general struc-
ture of surfactant II. Two well-separated, broad multiplets
represent the AA'XX1 spin systems for the expected aromatic
para substitution. The allcene proton signals which were
present in the starting material are now absent. The low
intensity, broad band centered at 277 Hz is readily assigned
as the sodium sulfonato methine proton (-CHSC>3Na) while the
absorption band at 216 Hz represents the ester methylene
and carbomethoxy protons (-CH2CO2CH3). The ratio of the
integration between these latter signals and the remaining
hydrocarbon peaks (30-170 Hz) verifies that this material
should contain at least 80% of the desired surfactant II.
Although the sodium sulfonato group is shown in a specific
location in the molecule, the analytical data does not
prove that this is the case. The sulfonato group can in
fact be in either the 2 or 3 position of the propionate
nucleus.
Surfactant IIIA; Sodium dodecylaminoethanesulfonate
(C12H25NHCH2CH2S°3Na)
The literature reported a simple procedure for the prepara-
tion of this surfactant^ in accordance with the following
reaction whereby sodium isethionate (b) and dodecyl-
amine (a) were merely heated together at atmospheric
pressure.
+ HOCH2CH2S03Na
IIIA
In our case, this method did not supply acceptable material
and, rather than go through lengthy procedures, we resorted
to the use of a parr pressure reactor. The reaction is
best accomplished without solvent in accordance with the
following procedure: The pressure reaction vessel was
charged with 12.2 g (0.82 m) of sodium isethionate and
158.6 g (0.86) of dodecylamine. The mix was heated with
stirring for 3 1/2 hours at 200-225°C and 2 hours at 245-
265 °C. The crude product from the reaction vessel was
washed with boiling hexane and, after drying in a vacuum
oven, the solid was extracted with boiling absolute
methanol. Removal of the solvent under reduced pressure,
followed by drying in a vacuum oven at 70°C/13 torr,
93
-------
.'T''".
f ^^^Mft*,,^^ rn^r^-^p. vsy 1^
'H»tw^^
74 *0 1A «O M 10 14 0 WM
.«/ .7..
.(.H
J«t .
'0.yjjlj Ijiigj. OlMlttM
-------
yielded a pale yellow powder which melted at 275-280°C,
showing decomposition at 175°C. Since this material is
amphoteric (possessing the amino and sulfonate functions),
cationic titration is of little value for estimating the
purity of this species.
The infrared spectrum of this product (KBr pellet)
exhibits strong signals at 8.45 and 9.35M (1183 and
1070 cm-1) which are characteristic of the sulfonate group
(asymmetric and symmetric stretching of -SCU respectively).
Medium intensity signals centered at 3.5 and 6.85^ (2857
and 1460 cm-1) along with the low intensity, broad group of
bands between 12 and 14M (833 and 714 cm-1) are due to the
presence of the C±2 hydrocarbon chain (C-H stretching,
-CH2 bending and (CH2)n rocking respectively).
The PMR spectrum of this product (No. 8) verifies the
structure of surfactant IIIA. The medium intensity signal
at 181 Hz is due to the methylene protons which are alpha
and beta to the sulfonato group (-N-CH^CH^SOqNa) where the
amino substitution on the $_ carbon has caused sufficient
deshielding of these £_ protons to give overlap with the a
sulfonato methylene hydrogens. The low intensity multiplet
at 152 Hz is due to the alkyl amino methylene protons
(C^^Hj3CH2N-). The remaining hydrocarbon protons appear
in the region of 40-115 Hz. Since this spectrum was
recorded as a solution in deuterium oxide, hydrogen-
deuterium exchange would cause the amino proton (-NH) to
appear within the HDO signal at 275 Hz. An integration
ratio of 4.4:2.0:23.0 for signals at 181, 152 and 120-40
Hz, respectively, is in good agreement with the assigned
structure and indicates a purity of at least 90%.
This surfactant possessed poor detergent properties and
possessed an objectionable pungent odor. These drawbacks
forced its elimination from the list of candidate
surfactants.
Surfactant IIIB; Sodium N-hydroxyethyl-2-dodecylamino-
ethanesulfonate (C
In consideration of the poor characteristics of the
preceding compound, from which this one was to be prepared,
no attempt was made to synthesize this surfactant (IIIB) .
95
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vO
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Surfactant IVA: Dodecyl 3-(sodium levulinate) sulfone
COCH3)
CH3COCH( SR) CH2C02Na °xldat:LOn>
IVA
In our work we used a commercial grade of levulinic acid
(a.) as the starting material. Our first experiments in
preparing the intermediate, b, duplicated the work of Kurd
and FerrarolO t,ut -we were not able to isolate sufficient
quantities of this material (3-bromolevulinic -acid) . The
following procedure, however, yielded good amounts of crude
material which was suitable for use in Step 2. Levulinic
acid, 32.5 g (0.28 m) was dissolved in 175 ml of dry
benzene in a 500 ml 3-neck flask which was equipped with
an internal thermometer, magnetic stirrer, gas equilibrating
dropping funnel and a reflux condenser which was topped
with a hydrogen bromide water trap. The solution was heated
to, and maintained at, 65 °C while 45 g (0.28 m) of bromine
was slowly added with stirring over a 1 1/4-hour period.
The trap at the top of the condenser was replaced by a
drierite tube as the flask was cooled to room temperature.
The reaction flask was then fitted with a gas inlet tube
which dipped well into the reaction mixture, the drierite
tube was replaced by the hydrogen bromide trap and the
system was purged with dry nitrogen until no hydrogen
bromide was detectable in the effluent from the outlet tube.
The benzene solution was separated from a small amount of
dark brown, benzene insoluble liquid (which was not investi-
gated) and the solvent was removed under reduced pressure,
leaving 53 g of amber oil. The PMR spectrum of this crude
product is shown in PMR Spectrum No. 9 while that of the
levulinic acid is given in PMR Spectrum No. 10.
Although Hurd and Ferraro-'-^ found that bromination of
levulinic acid yielded the 3,5-dibromo derivative as well
as 3-bromo compound, no evidence was found for the presence
of 5-bromolevulinic acid. We found that the crude product
isolated from our procedure of bromination in benzene is
of the following approximate composition: 64% 3-bromo-
levulinic acid; 13% 3,5-dibromolevulinic acid; 13% 5-bromo-
levulinic acid; 10% levulinic acid (unreacted starting
material) .
The above composition of the crude product was determined
from the PMR spectrum of this material. The structures
and proton designations follow.
97
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00
»H» SPJCTBUM Ho. I
Crude Product from
BroKlnatlon of Livullnlc
Acid In B*nt*n«
,_ itliwr-f _
ao.o
" frf-d
4.0 _
J>.J>«_
~J50 ~
_500 __
500 ~
}.0 ~
VTo"^
"nT ~
a componttont
STbromol«vullnie Acld-iW
},S-dibreMOl«vullnlo Ac14-1IK
Itvulinlo Acld-10*
-------
-------
Br Br
3-Bromolevulinic Acid 5-Bromolevulinic Acid
CH.COCH CH H, CO.H CH~COCH0CH_CO0H
I 2 | x a t> 2 3 222
r r Levulinic Acid
3,5-Dibromolevulinic
Acid
Comparison of PMR Spectrum No. 9 to that of levulinic acid
(Spectrum No. 10) allows for the assignment of the 133 and
162 Hz signals as the respective methyl carbonyl (CH^CO-)
and methylene (-CH^CH^-) protons of residual levulinic acid.
The high intensity signlet at 145 Hz is best interpreted
as the slightly deshielded methyl carbonyl of 3-bromo-
levulinic acid (CH^COCHBr-). This assignment comes from the
expectation that the electronegativity of the bromine at
this position would show a minimal amount of deshielding of
these carbonyl methyl protons which are two carbons removed.
The correlating bromomethine proton signal (-COCH^r-) is
seen as a multiplet centered at 279 Hz, where the effects
of direct bromination deshield the remaining proton (-Hx)
very greatly from the 162 Hz value for this position
methylene in levulinic acid. Additionally, the methylene-
carboxy protons of 3-bromolevulinic acid (C-CHgH, CC^H)
would feel the effects of an adj acent bromo substitution
and are found as a multiplet centered at 188 Hz.
The apparent singlet at 237 Hz is interpreted as the bromo-
methylene of 5-bromolevulinic acid (CHoBrCO-). The
methylene group which is adjacent to the ketone group
(-COCH2-C-) in this molecule would be expected somewhat
downfield (ca 10 Hz) from 162 Hz which is its position in
levulinic acid. The remaining methylene group of 5-bromo-
levulinic acid (-C-CH2-CC>2H) would be expected to appear
at about the same position as in levulinic acid.
The presence of a small amount of 3,5-dibromolevulinic acid
in this crude material is indicated by the very low
intensity multiplet centered at 300 Hz. These signals are
assigned as representing the 3-bromomethine proton
(-COCHxBr-C-) of this molecule where additional bromination
at the 5 position has supplied enough of a deshielding
effect so as to separate it from the same signal of the
3-monobromo derivative. The carboxymethylene signals
(-CH2CO2H) would be expected in the region of 188 Hz while
the bromomethylene (CH2BrCO-) protons would be expected
somewhat downfield from the 5-monobromo derivative. Thus,
the apparent doublet centered at 257 Hz answers this final
100
-------
expectation. The anomaly that this latter assignment is a
doublet rather than an expected singlet might be
rationalized on the basis of restricted rotation about the
carbonyl carbon caused by 3,5-dibromo substitution. The
carboxylic acid protons for all species appear at 611 Hz.
There are four signal areas in the PMR spectrum of the
crude product which, individually, represent one of each
of the components of the mixture. Furthermore, the regions
are separated enough so that their integrations can be used
to determine an approximate composition. The signal areas
involved are those at: (1) 300 Hz, representing the
bromomethine (-COCHxBr-C) of 3,5-dibromolevulinic acid,
(2) 279 Hz, representing the bromomethine (-COCHxBr-C) of
3-bromolevulinic acid (the carbonylmethyl of this species
at 145 Hz is also separated well enough to be used for
this purpose and corroborates the analysis which uses the
signal at 279 Hz), (3) 237 Hz, representing the bromo-
methylene (CH^BrCO-) of 5-bromolevulinic acid, and (4) 133
Hz, representing the methyl carbonyl (CH3CO-) of levulinic
acid. Equalizing the integrations with respect to the
number of protons involved in the signal regions and
calculating their ratios yielded the composition given
above.
Because distillation caused significant decomposition of
the products and further attempts to purify this material
(e.g., crystallization) were unsuccessful, we chose to
use this material as is for the next step of the synthesis.
This, of course, was done with the hope that purification
of the next intermediate would be easier to accomplish.
In this next step, 15.8 g of potassium hydroxide was
dissolved in 50 ml of absolute ethanol in a flask which was
equipped with a magnetic stirrer, internal thermometer, gas
equilibrating dropping funnel and a reflux condenser which
was topped with a drierite tube. n-Dodecylmercaptan, 20.2 g
(0.1 m), was added to the ethanolic KOH solution and, after
1 minute of stirring, 24.4 g of the crude brominated acid
product was added over a period of 1.25 hours. The
addition was done in such a manner so as to maintain a
31-32°C internal temperature range. The precipitated
potassium bromide was filtered and the clear filtrate was
stripped of solvent at reduced pressure. The residue
(36.6 g) was dissolved in 200 ml of water and the solution
was acidified with concentrated HC1 (6 ml) to a pH of 3
(pHydrion paper) while cooling in an ice bath. The
precipitate was filtered, pressed dry in the filter,
allowed to air dry and then placed in a vacuum oven at
50°C/10 torr. Upon cooling to room temperature the
residual oil solidified yielding 33 g of waxy, low melting,
tan solid. This material was very soluble in all common
organic solvents but was recrystallized from an acetone-
water solvent system. The PMR and IR spectra of the
101
-------
recrystallized material were virtually the same as the
crude product.
PMR Spectrum No. 11 is that of the 'crude product obtained
from treatment of the bromo acids with potassium n-dodecyl -
mercaptide and leaves no doubt that the mercaptide
effectively displaced the bromo groups of the brominated
levulinic acids to give a mixture of thioethers. The loss
of all signals downfield of 221 Hz (except the acid proton
at 642 Hz) indicates that no bromo acids were present in
this material. The work-up for this reaction apparently
eliminated the presence of unreacted levulinic acid since
there is no appreciable absorption in the region of 131 Hz
where the methyl carbonyl (CHqCO-) of levulinic acid would
appear. Because sulfur substitution has less of an
electronegative effect than bromine/ the signals are not
separated as much as those of the bromo derivatives. Even
so, interpretation of the data leads us to conclude that
this material is a mixture consisting of about 80% of the
desired n-dodecyl 3-levulinic acid sulfide (c) and 20%
n-dodecyl 5-levulinic acid sulfide (CH
The signals centered around 221 Hz represent the thio-
methine proton (-COCHS-) of the 3-bromo compound while
the signal at 194 Hz would represent the thiomethylene
protons (-SCH2CO) of the 5-bromo acid. The sharp signal
at 140 Hz represents the carbonylmethyl group (CH^CO-)
of the 3-substituted levulinic acid (c) . This signal
overlaps in the area of absorption for a methylene group
which is directly bonded to sulfur (-CH2S-). The source of
these latter signals would, of course, be from the n-dodecyl
chain (Cn^^-CH^S-) . The high intensity signal at 75 Hz
is from the hydrocarbon chain methylene (-CH2) groups
while the small signal area at 53 Hz is due to terminal
hydrocarbon methyl protons (CH3-C-) . The infrared spectrum
of the crude sulfide confirmed the presence of the
carboxylic acid and ketone functional groups.
A number of attempts were made to oxidize the mixture of
thioethers to their desired sulfone derivatives. None of
these experiments were successful in supplying the desired
surfactant IVA. Therefore, the value of this type of
surfactant in phosphate-free formulations was not investi-
gated.
102
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o
U)
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1
5
Accession Number
n Subject Field & Group
05G
SELECTED WATER RESOURCES ABSTRACTS
INPUT TRANSACTION FORM
Organization
IIT Research Institute, Chicago, Illinois
Title
DEVELOPMENT OF PHOSPHATE-FREE HOME LAUNDRY DETERGENTS
10
Authors)
Roseman, Karl A.
Linfield, Warner M.
16
21
Project Designation
16080DVF07/70
Note
22
Citation
23
Descriptors (Starred First)
Detergents,* Algal Control,* Formulation,* Surfactants,*
Eutrophication, Linear Alkylate Sulfonates, Chelation, Phosphates,
Organic Compounds, Water Pollution Control
oc TIdentifiers (Starred First)
Phosphate-free detergents*
27
Abstract
Basic studies were performed towards the development of phosphate-free home
laundry detergents. Five surfactants were synthesized with the idea that
they might possess hard ion chelating properties. The cleaning abilities
of these materials were compared to the widely used linear alkylbenzene
sulfonate as incorporated into the same formulations.
The detergent compositions contained 2% carboxymethylcellulose and the
silicate content was varied. Sodium acetate and sodium carbonate were
investigated as possible reservoirs of alkalinity. Surfactant compatibility
with sodium chloride and sodium sulfate was examined. Other additives
included trisodium nitrilotriacetate and sodium citrate at moderate levels.
Fifteen detergent formulations were screened and the results leave little
doubt that acceptable phosphate-free home laundry detergents can be
developed.
Abstractor
•actor , _ _
ICarl A. Roseman
Institution
IIT Research Institute
ORlU
SEND TO: WATER RESOURCES SCIEN TIFIC IN FORTU ATION CENTER
U.S. DEPARTMENT OF THE INTERIOR
WASHINGTON. D. C. 20240
WR-.IO2 (REV. JULY 18691
WRSIC
* too: 1969-339-338
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