Federal Water Pollution Control Administration
           Division of Water Quality Research
          Analytical Quality Control Laboratory
                  Cincinnati, Ohio
LABORATORY GUIDE FOR THE IDENTIFICATION
          OF PETROLEUM PRODUCTS
                 January, 1969
          U.S. DEPARTMENT OF THE INTERIOR

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   Laboratory Guide for the Identification

            of Petroleum Products
                     by

      Fred K.  Kawahara, Ph.D., F.A.I.C.
       U. S. Department of the Interior
Federal Water Pollution Control Administration
      Division of Water Quality Research
     Analytical Quality Control Laboratory
                1014 Broadway
            Cincinnati, Ohio 45202

                January 1969

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                              Contents




                                                                  Page




  I.  INTRODUCTION  	  1




 II.  SAMPLING	2




      A.  Collection	2




      B.  Preservation of Samples 	  3




      C.  Sample Preparation for Analyses 	  3




      D.  Concentration 	  5




III.  PRELIMINARY SOLUBILITY STUDIES  	  7




 IV.  SEPARATION, ANALYSES, AND CHARACTERIZATION  	10




      A.  Determination of API Gravity	10




      B.  Doctor Test	16




      C.  Determination of Sulfur 	 18




      D.  Determination of Distillation Ranges  	 18




      E.  Determination of Molecular Weight by the Rast Method  •  .19




      F.  Determination of the Melting Point  	 20




      G.  Determination of the Viscosity	21




  V.  IDENTIFICATION	23




      A.  Gas Chromatography	24




      B.  Chromatographic Analyses	24




          1.  Hydrocarbons	26




          2.  Alkyl benzenes through C,0	27




          3.  Results	28




          4.  FIA method D 1319-61T	28




      C.  Infrared Analyses	29




      D,  Trace Constituent Analyses  	36




 VI.  REFERENCES	40

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                               ii
                             Tables
                                                              Page
Table I.    Properties of Petroleum Products 	   6

Table II.   Solubility of Petroleum Products 	   9

Table III.  Distinguishing Features of Petroleum	12
              Products

Table IV.   Petroleum Products with Similar API	14
              Gravity Ranges

Table V.    Properties of Petroleum Products -	22
              Viscosities

Table VI.   Most Frequently Used Band Assignments	32

Table VII.  Ratios of Infrared Absorbances of	34
              Commercial Asphalts & #6 Fuel Oils

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             Laboratory Guide for the Identification




                     of Petroleum Products




                               by




                     Fred K. Kawahara, Ph.D.






                          INTRODUCTION




     Oil pollution has become a major problem in the coastal and




surface waters of the United States and many other countries.  Oil




discharges and spills from industrial plants and commercial ships




produce unsightly and unhealthy conditions which ruin beaches and




recreational areas, impart unpleasant taste and odor to water, and




in many cases result in harm to fish and other aquatic life.  Larger




oil spills will occur more frequently as the demand for petroleum




products becomes greater and ocean oil transports become larger.




     The urgency of the problem requires that detailed analytical




procedures be developed to detect and identify petroleum pollutants,




in order to establish responsibility for violations of water quality




standards and to secure abatement of the pollution.




     Many oil spills occur without eye witness.  In such cases




technical information and data will be necessary to facilitate




locating and identifying the sources of the pollution created by




petroleum products.  Following identification, proper enforcement




for control procedures may then be exercised.

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                               _ 9—




     This laboratory guide for the identification of petroleum




pollutants has been prepared to provide the analyst with specific




methods leading to a positive characterization of the waste




material.






                            SAMPLING




Collection




     Oily materials may be collected from the surface of the water




by means of three devices.  The first is a glass, wide-mouth filter-




ing funnel, connected by teflon tubing to a two-way stopcock.  Volatile




oil product found upon the water surface is ladled with the aid of this




device; the lower water phase is discarded by opening the stopcock.




The upper petroleum phase is transferred to a large container.   Ladling




and water-discard operation should be repeated until a sufficient




amount of oil (10 grams or more) is collected.




     An alternative collector is a paint-free dustpan with a suitable




stopcock attached to the handle.  Collection and concentration of




several grams of petroleum product can be achieved with this household




device.  Heavy, viscous material,  such as asphalts, can be collected




in a similar manner.   Transfer to the final collecting jar from the




funnel, jar, or dustpan, is possible with aid of a clean spoon or stick.




     The third device is a large household mop with a ringer attachment.




It is suggested that, before use,  the sponge, whether derived from

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                               -3-




natural or synthetic materials, be rinsed thoroughly with a proper




solvent, such as chloroform.  This mop is passed through the oil




pool; the absorbed materials are squeezed out and transferred by




means of a funnel into the collecting jar.  The sampling operation




is facilitated by attaching the bottle, scoop, or mop to a long




pole.  Where possible, reference samples of oil should also be




obtained from vessels or shore facilities.






Preservation of Samples




     The samples containing oil and water are protected against




autoxidation (15) and other chemical conversions by removal of air



and exclusion of light.  Carbon dioxide may be used to displace air.




If dry ice is available, a piece (approximately 0.5 cu inches) may




be added to the sample.  As soon as the effervescing has stopped,




the jar is sealed with a teflon lined cap.  The bottle is not capped




if unused portions of solid dry ice are visible.  Samples should be




preserved in the refrigerator whenever possible.



     When nitrogen or an inert gas is not available, the sample bottle



is filled carefully to the top with water to displace air.






Sample Preparation for Analyses




     To prepare a volatile petroleum sample for analysis, the water




sample is extracted with distilled pentane or, if necessary, with




purified dichloromethane or chloroform.  To a 500 ml separatory funnel

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                               -4-




200 ml of pentane is added.   A portion amounting to about  one-half




gram to five grams of petroleum pollutant is added to the  pentane




solution.  The extent to which the petroleum material dissolves in




the pentane is observed.  Dichloromethane or chloroform is used, if




necessary, to dissolve the pollutant.   The separatory funnel is




tilted back and forth for one minute to extract the product.  The




funnel is set on a ring stand and is placed under a well ventilated




hood.




     After the lower phase is drawn off, the 200 ml pentane extract




containing the petroleum pollutant is washed once with 10  ml of dis-




tilled water, and the lower aqueous layer is drawn off.  (For the




dichloromethane system, the aqueous layer will be on top.)




     The extract layer is then dried by permitting the solvent mixture




to pass dropwise through 5 grams of anhydrous sodium sulfate held in a




No. 12 folded filter paper seated on a filtering funnel with a 75 mm




diameter and 75 mm stem.  The filtered, pollutant extract  is collected




in a 300 ml round-bottom flask equipped with a standard taper 24/40




ground-glass joint.




     If the petroleum product is thought to be less volatile than




gasoline or kerosene, chloroform should be used as the extracting sol-




vent.  Thus, greases, asphalts, residual oils, etc., are extracted




with chloroform; the extract is washed with distilled water and is




dried over anhydrous sodium sulfate prior to the concentration step.

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                               -5-




Concentration




     For the removal of pentane or chloroform, the distillation appa-




ratus, similar to that suggested by Fieser (10) is used.   A modified




Pauly (22) receiver, made from a 125 ml Erlenmeyer flask, is attached




to the adapter which follows the water condenser.   Another modifica-




tion is the use of 19/38 standard taper ground-glass joints at all




connections except the Claisen distilling head which is fitted with a




24/40 standard taper joint.  The distillation flask is fitted to the




Claisen head by means of a ground-glass joint.  The Claisen head is



equipped with an ebullating tube through which the nitrogen gas is bled




slowly, and the ebullating tube is fitted with a 10/30 standard taper



joint.  A thermometer well is fitted at the outlet of the Claisen head.




     The Pauly receiver (22) is connected by means of a foot-long




suction tubing to a dry ice trap, which is fitted with an inlet and




outlet exhaust gas stopcock.  The exhaust gas stopcock is connected to




a mechanical vacuum pump or line.  Heat is provided by a thermostatted



water bath.  Extracting solvent (pentane, dichloromethane, or chloro-



form) is removed with aid of vacuum, from the laboratory vacuum line




or a high vacuum mechanical pump.



     When the pollutant is considered to be a petroleum product other




than crude, naphtha, gasoline or jet fuel, it is recommended that the




solvent mixture containing the volatile pollutant be subjected to the




milder atmospheric distillating condition.  Table I shows the high




volatility of some of the petroleum products.

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 PAGE NOT
AVAILABLE
DIGITALLY

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                               -7-

Volatile solvents and petroleum products are recovered in the Pauly

receiver or in the dry ice trap.  Distillates are analyzed to deter-

mine the presence of material other than the extracting solvents.

The refractive index of the extracting solvent should be determined

prior to the extraction procedure, using an Abbe refractometer.

     During the final stages of concentration, the concentrate is

transferred to a 25 or 50 ml flask.  The removal of the solvents

concentrates the oil pollutant into a small volume.

     An alternative method for preparing the sample for analysis is

separation by centrifugation.  This method is suitable for large

volumes of liquid petroleum pollutants admixed with water.  However,

the removal by centrifugation of traces of water from the viscous

material or from minor amounts (0.1 gram) of actual liquid sample is

difficult.   The extraction procedure is therefore recommended in

these instances.


                 PRELIMINARY SOLUBILITY STUDIES

     In spite of the complex structures of petroleum products it is

possible to make some reasonable prediction as to product type by

observing the behavior in organic solvents.  This preliminary obser-

vation is especially useful for identifying the heavier petroleum

products.
 Mention of products and manufacturers is for identification only and
 does not imply endorsement by the Federal Water Pollution Control
 Administration, U. S. Department of the Interior.

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                               -8-




     From the thoroughly dried residue, free of water and extracting




solvent, a 0.2 gram portion is taken and placed into a 20 ml  vial.




Seven ml of hexane is added and the mixture is stirred with a




spatula.  The solubility of the residue is observed in this solvent.




This test is repeated to determine solubility in diethyl  ether and  in




chloroform.  If the material is soluble in each of the three  solvents




in the cold, the material can be assumed to be one of the following:




light or heavy naphtha, kerosene, gas oil, white oil, certain types




of cutting oils, motor oils, paraffin, diesel oil, or jet fuel.




     Vaseline or white petroleum jelly is only partly soluble in




hexane, in ether, and in chloroform.  Thus, vaselines are unique.




However, greases, heavy residual oil (#6) and asphalt (feed stocks)




are insoluble in hexane and in diethyl ether, but are readily soluble




in chloroform.




     These solubility characteristics of petroleum materials  are




summarized in Table II.

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                    -9-
Table II.  Solubility of Petroleum Products
Product
Light naphtha
Heavy naphtha
Gasoline
Jet fuel
Kerosene
Gas oil
Diesel oil
White oil
Cutting oil
Motor oil
Paraffin wax
White petroleum jelly
Grease
Residual fuel oil
Asphalt feed stock
Hexane
VS
VS
VS
VS
VS
VS
VS
VS
S
S
S
PS
I
I
I
Ether
VS
VS
VS
VS
VS
VS
VS
VS
S
S
S
PS
I
I
I
Chloroform
VS
VS
VS
VS
VS
VS
VS
VS
S
S
S
PS
S
S
S

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                              -10-



The solubility behavior of 0.2 gram of material was  observed in 7 ml



of the cold organic solvent,





           SEPARATION, ANALYSES, AND CHARACTERIZATION



     The remaining dried residue obtained from the concentration



step is divided into two portions.  One portion is used to determine



the API gravity, infrared spectra, and molecular weight.   With care,



the residue may be recovered.   The other portion is  used to determine



the sulfur value, distillation range, and viscosity  or refractive



index.  For subsequent identification, the gas chromatographic anal-



yses of the more volatile petroleum products and the infrared analyses



of the less volatile products  will be performed.



     After the solubility behavior has been determined, the data of



Table I and II are consulted for guidance.





Determination of API Gravity



     The analyst is referred to ASTM D 287 (1) for determining the API



gravity by means of the hydrometer.  If the sample size is limited,



the density may be measured by the pycnometric methods, ASTM D 941 and



ASTM D 1217 for liquids.  The  density is referred to 60°F.  Then,



degrees API =  141<5  - 131.5.  If sufficient liquid is available,
              sp.gr.


the use of the chainomatic specific gravity balance  is convenient for



15 ml samples.



     For viscous oils, the preferred method is ASTM D 70 and for solids



the ASTM D 71 method is used.

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                              -11-



     If the residue, after concentrating and drying, is completely




soluble in each of the three solvents,  the density or the API gravity




is determined.  The second test will determine whether the sample is



high or low gravity naphtha, gasoline,  jet fuel,  kerosene, gas oil,




motor oil, fuel oil //I, fuel oil #2, or fuel oil  #4.  Table III shows



the distinctive properties of each petroleum product.

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                              -12-

     Table  III.   Distinguishing Features of Petroleum Products


 Crude  Oil               - most frequently sour, wide boiling range

 High g. naphtha         - low sulfur

 Low g. naphtha          - low sulfur

 Gasoline                - lead, halogens (phosphorus or boron?)

 Jet fuel                - low sulfur, API gravity - additives

 Kerosene                - low sulfur, API gravity

 Gas oil                 - higher sulfur and API combination

 Diesel oil              - similar to Kerosene, Fuel Oil #1

 White  oil               - paraffinic (IR), colorless

 Cutting oil             - glycerides, sulfur, (halogens), mineral oil

 Motor  oil               - metals (Zn) , phosphorus, sulfur, additives,
                         frictional properties low

 Paraffin wax            - solid, paraffinic (IR)

 White  petroleum jelly   - partly soluble in hexane, in ether, and in
                         chloroform

 Grease                  - metal soaps?, low frictional properties;
                         hexane and ether insoluble, soluble in
                         chloroform

 Fuel oil #1             - similar to Kerosene; low sulfur, API gravity

 Fuel oil #2             - Kinematic viscosity

 Fuel oil #4             - Kinematic viscosity

 Fuel oil #5             - Kinematic viscosity

 Fuel oil #6             - hexane and ether insoluble, soluble in chloro-
                         form, ratio of infrared absorbances

Asphalt                 - hexane and ether insoluble, soluble in chloro-
 (Blown or feed)          form, ratio of infrared absorbances, since
	:	similar to Fuel Oil- #6

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                              -13-




Advantage can be taken of these properties in order to distinguish the




products from each other.




     Table IV groups four sets of petroleum products into similar API




gravity ranges.  Since the gravity alone will not be sufficient  to




produce distinctiveness, other properties are given to provide additional



evidence for characterization.

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                                 -14-
    Table IV.  Petroleum Products with Similar API Gravity Ranges
Product
High gravity naphtha
Low gravity naphtha
Gasoline
High gravity naphtha
Low gravity naphtha
Jet fuel
Fuel oil #1
Kerosene
Low gravity naphtha
Gas oil
Paraffin wax

White oil
Motor oil
Fuel oil #2
Gravity
API
45
30
58
45
30
40

40
30
30
34

29
24

- 75
- 53
- 62
- 75
- 53
- 55
>35
- 46
- 53
- 33
- 39

- 32
- 30
>26
ISO. O *- J- •»•
iB.P.
95°
160°
96°
95°
160°
100°
360°
355°
160°
400°
MP =
196


370°
AU ^ -tWfc*
-eP.
- 206°F
- 410°F
- 408°F
- 206°F
- 410°F
- 500°F
- 625°F
- 575°F
- 410°F
- 8008F
1478-
°F


- 675°F
Comment





lead, colored
S <0.02%
S <0.02%
s 
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                              -15-




     Therefore, the two naphthas and gasoline can be differentiated




from each other by comparing the initial and final boiling points of




the material.  Jet fuel and gasoline are different in the end point




and in the API gravity values.  Jet fuel differs from the low gravity




naphtha in the initial and final boiling point range as well as in the




sulfur content.  Kerosene is distinguishable from the naphtha and jet




fuel in initial and final boiling points.




     In some cases the sulfur and API gravity values will help in




differentiation.  Gas oil is distinguishable from the six petroleum




products mentioned above in both API gravity and boiling range or




sulfur values.




     Motor oil is soluble in all three solvents, hexane, ether, and




chloroform.  It is characterized by a narrow range of API values.




Motor oil differs from white oil, gas oil, and naphtha, having a




higher initial boiling point.  Indeed, the motor oil has a charac-




teristic phosphorus to sulfur ratio of 0.5.  Zinc is present at about




1/2 of the phosphorus value.  High ash content is characteristic of




motor oil and most greases.




     Fuel oil #1 can be used as a diesel fuel, in which case amyl




nitrate will be present.  This product is quite similar to kerosene.




     White oil is distinctively colorless.  It is paraffinic as




indicated by the infrared spectrum.




     Fuel oils #1, #2, #4, and #5 show distinctive kinematic viscosity




values at 100QF.  Also, the latter three fuel oils have unusually high

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                              -16-




sulfur values, and thus may be readily distinguished from the




naphthas, gasoline, and jet fuel.  The fuel oil API gravities are




distinctly lower than the API gravities of naphthas, gasoline, and




jet fuel.




     Generally, crude oils contain mereaptans which can be detected




by the use of the doctor test (6) involving the reaction of sodium




plumbite and sulphur.  The characteristic reaction of black precip-




itate shows the presence of mereaptans which are converted to the




dialkyl disulfide and polysulfides.






Doctor Test




     One hundred and twenty-five grams of sodium hydroxide are dis-




solved in one liter of distilled water.  To the mixture, 60 grams of




lead oxide are added.  The entire mixture is shaken, permitted to




stand for one day, and then filtered.




     A 10 ml test sample is vigorously shaken in a test tube with 5 ml




of the freshly filtered sodium plumbite solution.  A pinch of sulfur




is added and the contents are shaken vigorously for 15 seconds.




Sufficient sulfur is added so that most of it floats at the interface




of the two phases.  If the mixture is discolored, the test is reported




as positive.  If the sulfur or the mixture remains unchanged or yellow,




the test mixture is considered sweet or mercaptan-free.




     In characterizing the crudes, their wide distillation range is a




useful property.

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                              -17-




     Paraffin wax ±s identifiable as a colorless solid with a wide




melting point range.  It is soluble in hexane, in ether, and in




chloroform.  The infrared spectrum shows only long chain paraffins.




     White petroleum jelly is only partially soluble in each of the




three solvents.  Its infrared spectrum shows strong paraffinic




character and little or no aromatic character.




     Grease, asphaltic material, and residual fuel oil #6 are




characteristically insoluble in hexane and ether solvents.   However,




the three petroleum products are soluble in chloroform.




     Greases are characterized by a high metals content.  Metals such




as lithium, sodium, calcium, barium, zinc or lead, may be present.




When the metals are absent, the nitrogen content may be




high.  The grease will then be only partially soluble in chloroform.




Thickeners may be graphic, silica, ureas, or ammeline.   Silicones




fluorocarbons, esters, or organic acid moiety, or lube oil  may be




present.  The infrared spectra may indicate these groups.




     The two remaining petroleum products, asphalts and fuel oil #6,




have unusually low API gravity.  These materials have usually higher




sulfur values and high content of nickel and vanadium.   They are higher




boiling materials.   These products are differentiated from  one another




and also identified by use of comparative ratios of infrared absorb-




ances (12, 16), even though the products have similar infrared spectra.




Three infrared absorbances are used to yield two ratios which provide

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                              -18-




a linear relationship involving aromaticity, paraffinicity, and branch-




ing.  This newly-developed tool shows excellent promise.




     After the API gravity and solubility behavior have been determined,




additional evidence for characterization of the unknown petroleum




product may be obtained by determining the sulfur or distillation range




values.






Determination of Sulfur




     The determination of volatile organic sulfur compounds may be




conducted in the manner described by Martin and Grant (18).  A




satisfactory procedure for the total organic sulfur, whether volatile




or non-volatile, is that described by Belcher (A).   The oxygen-bomb




method of decomposition is used and the final, almost pure solution,




is titrated with barium perchlorate-Thorin.  In this method the




evaluated sample sizes varied from 10 to 30 ug of organic sulfur.




This method was selected after a lengthy study for completeness of




decomposition, and colorimetric titration of numerous methods.   Special




procedures are given for interfering iodine and phosphorus.  This




method has been quite successful.






Determinationxof Distillation Ranges (1)




     The distillation range of naphtha petroleum products is determined




by the ASTM D 86-56, while the boiling range of the aromatics may be




determined by the ASTM D 850.  A special procedure, ASTM D 216, is




highly recommended for very volatile naphthas.  In  the latter method

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                              -19-




the apparatus is identical to ASTM D 86-56 except that a lower range




thermometer is used.  Also, there is a slight variation in procedure




of the ASTM D 216n54 when compared to that of ASTM D 86-56.




     The ASTM D 86 method of test is intended for use in the distil-




lation of gasoline, naphtha, kerosene, and similar petroleum products.




The initial boiling point is recorded as the reading of the distillation




thermometer when the first drop falls from the end of the condenser.




The end point is the highest thermometer reading observed during the




distillation of the product under test.  Appropriate distillation




apparatus and directions for the method are described.  (It should be




recognized that evaporation and contamination in surface waters will




affect the readings in all determinations listed).




     The determination for the molecular weight is given below since




this test is of value for low and high boiling petroleum products.




The test is not necessary in most cases.






Determination of the Molecular Weight by the Rast Method (21)




     About 50 mg of the dried, retrieved material is placed into a




weighed, four-inch test tube.  The weight is taken.   About 500 mg of




d-camphor is added and contents are weighed.  Before heating, the test




tube is stoppered.  The contents are melted by placing the tube in a




heated oil bath.  A clear solution results.  The tube is swirled to




mix the contents as a clear solution.  The mixture is heated no longer

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                              -20-



than one minute and cooled.  The solid is powdered.  (This method



may be replaced by the ebulloscopic or mass spectroscopic method



for the volatile materials.)



     The melting point of the mixture is determined in a melting



point tube, using a thermometer which reads to 0.2°F.   Melting points



of several samples from the mixture are determined and the average



value is calculated.  The melting point of the original camphor is



taken.  The difference, ZA , between these two temperatures is the



depression of the melting point of the mixture.



     The molecular weight is calculated from the following formula,





                     „   40 X w X 1000
                     M =	

                            ^A-w



in which w is the weight of the material, W is the weight of camphor,



and 40 is the molecular freezing point depression constant for camphor.



     If the unknown petroleum pollutant is found to be insoluble or



partly soluble in chloroform, a melting point is determined for the



material.  Ammeline, ureas, and waxes are typical solids.






Determination of the Melting Point (1)



     The determination of the melting point for petrolatum and for



microcrystalline wax is the ASTM D 127-49.  The ASTM petrolatum



melting point is that temperature at which the material becomes



fluid to drop from the thermometer.

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                             -21-




    ASTM D 87-57 describes the procedure for the determination of




the melting point of paraffin wax.  ASTM paraffin wax temperature




is that temperature at which the melted wax first shows a minimum




rate of temperature change when cooled under the prescribed condi-




tions.  A temperature versus time cooling curve is plotted from




the periodic temperature readings.  The minimum rate of temperature




change is usually represented by a plateau in the cooling curve.




    The API gravity and solubility studies will not yield sufficient




information to characterize asphalt, fuel oil #6, or greases.   These




products are insoluble in ether and in hexane, but are soluble in




chloroform.  Greases are characterized by low frictional properties.




Metals such as lithium, barium, zinc, or lead may be present in the




greases.  Since lube oils and fuel oils have distinctive viscosity




(kinematic), this measurement is suggested.  Such measurements will




differentiate fuel oil #1, #2, #4, #5, and #6.






Determination of the Viscosity (1)




    In Table V the wide range of viscosity of the petroleum products




is illustrated.

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                   -22-

Table V.  Properties of Petroleum Products-
             Viscosities (23)
Type of Oil
Natural gasoline
Gasoline
Water
Kerosene
Distillate
An average 1. crude oil
Average crude oil
Average crude oil
An average h. crude oil
Wyo. crude oil
ASTM Fuel 3 (max. vis.)
ASTM Fuel 5 (min. vis.)
SAE 10W lube
SAE 20W lube
Thin SAE 10 lube (100 V.I.)
Thin SAE 10 lube (0 V.I.)
Thin SAE 30 lube (100 V.I.)
Thin SAE 30 lube (0 V.I.)
ASTM Fuel 5 (Max. Vis.) or
Fuel 6 (min. Vis.)
Average SAE 50 lube
(100 V.I.)
Average SAE 50 lube
(0 V.I.)
Thick SAE 70 lube (100 V.I.)
Thick SAE 70 lube (0 V.I.)
ASTM Fuel 6
Bunker C (max.)
M.C. residium
Asphalt
Viscosity
Saybolt




37 at 100°F
33 at 100 °F
40 at 100 °F
50 at 100°F
60 at 100°F
40 at 100°F
45 at 100°F
50 at 100
10,000 at 0°F
40,000 at 0°F
90 at 130°F
90 at 130°F
255 at 130°F
255 at 1308F
(Furol)
40 at 122 °F
90 at 210°F

90 at 210°F
150 at 210°F
150 at 210°F

(Furol)
300 at 122 PF
300 at 210°F
(50 penetration)
API
76.5
57.0
10.0
42.0
35.0
48.0
40.0
35.6
32.6
36.4
26.0
15.0
200 at 100°F 31.0
320 at 100°F 29.0
160 at 100°F 30.0
180 at 100°F 27.0
70 at 210° F 26.0
58 at 210°F 21.0
800 at 100° F 11.0
986 at 100°F 25.0

2,115 at 100°F 19.0
23.0


8.0
19.8


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                              -23-




The API gravity is also given with the Saybolt viscosity for each




petroleum product.  It should be recognized that these are examples.




As crude oils vary widely in composition and are subjected to




different processes for manufacture of petroleum products, these




figures will deviate strongly.  However, a characteristic viscosi-




metric value may yield a clue as to the identity of the product type.




Consideration of the API gravity, with sulfur values, infrared data,




with boiling point range will facilitate the identification of the




product.




     Viscosity is the measure of the internal resistance of an oil to




flow.  Values are usually expressed as the number of seconds in time




required for a certain volume of the oil under test to pass through a




standard orifice under prescribed conditions.  For kinematic viscosity




the tentative method of test is ASTM D 445-53T.  It is the absolute




viscosity divided by the density, both obtained at the same temperature




of determination.  The unit of measurement is the centistokes.  Con-




version of the kinematic viscosity to Saybolt Universal Viscosity for




100° and 210°F values is provided in the conversion table included in




ASTM D 446-53.






                         IDENTIFICATION




     The techniques and methods useful for the characterization of the




numerous petroleum pollutants have been outlined.  To further identify




the petroleum pollutant, several additional analytical tools are avail-




able.  These are principally infrared spectroscopy and gas chromatography.

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                              -24-




A third method involves the analyses of trace metals and other minor




constituents.






Gas Chromatography




     Gas chromatography is one of the most efficient general methods




for separating components in a mixture.  However, the effectiveness




of the chromatographic separation process is highly dependent upon




use of the proper column.  Important parameters that govern perfor-




mance and resolution must be considered (8, 17).






Chromatographic Analyses




     For the identity of classified, volatile petroleum products, such



as naphthas, gasoline (24), jet fuel, and kerosene, it is highly




recommended that the dried, recovered residual material be analyzed



by gas chromatography.  As volatility is a strong characteristic of




the above products, a portion representing the volatiles of the gas



chromatographic spectrum of the reference or known sample will be



missing in the unknown petroleum sample which is exposed for long



period.  Time and temperature of the environment, as well as the fuel



volatility, must be considered in matching the unknown with the




reference sample.  If the gas chromatogram of the unknown shows qual-




itative and quantitative match with the reference sample, except for




reference peaks which represent compounds of high volatility or




solubility in water, the two products can be judged as being from the



same source.

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                             -25-




    The use of the gas chromatograph as a means to identify the




heavier products, such as residual oils and asphalt, is limited.




However, gas oils, paraffins, white oils, and motor oils can be




identified by this method, if they are volatile under the condition




of analysis.




    Martin and Winters (19, 20) have developed a special method




for determining saturates through C7 and alkyl-benzenes through C,0




in crude oils.  The hydrocarbons to be determined are separated




from the crude oil with a packed prefractionator column, collected




in a liquid nitrogen trap, and then released into either of two




capillary columns through a stream splitter.  Components through C?




are well resolved in four hours on a 500-foot capillary column with




1-octadecene.  Alkyl benzenes through C,Q are resolved on an 800-foot




column coated with polyethylene glycol.  Uncertainties in the results




generally are less than 6% relative.




    To characterize crude oils fully, detailed knowledge of compo-




sition is needed.  Conventional methods involve analyzing narrow-




boiling distillate fractions with a variety of techniques (B.P. ,




R.I., U.V., etc.).  Results are usually satisfactory, but analyses




are prohibitively lengthy.




    Packed columns have been used for determining individual com-




ponents in crude oil but resolution is far from ideal.  However,




this method is accurate, detects trace components, and does not




involve a prior distillation.  Hydrocarbons of a selected boiling

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                             -26-




range are separated from the crude oil by the prefractionator column




and are collected in the liquid nitrogen trap.  The prefractionator,




a short packed gas chromatographic column, fractionates approximately




by boiling point differences.  After the desired boiling range




fraction has been trapped, the prefractionator is bypassed by chang-




ing the position of the four-way valves.  The trap is then warmed




and the hydrocarbons are carried into the capillary column through




the stream splitter.  The individual components are detected by




hydrogen-flame ionization as they emerge from the column.  Volatile




compounds remaining on the prefractionator are removed by back




flushing.  For determining hydrocarbons through C7, a capillary column




coated with 1-octadecene is used.  For alkyl benzenes through C-0, a




column coated with polyethylene glycol is used.






Hydrocarbons




    The column is a 500 feet by 0.001 inch stainless steel capillary




coated with 1-octadecene.  All hydrocarbons through C_ and 10 lowest




boiling Co are well resolved, when the column is operated at 30°C with




helium-exit flow of 0.85 ml per minute at a gauge pressure of 35 p.s.i.




A temperature of 30°C gives optimum resolution.  With a change of




temperature on the octadecene column, the elution position of some




hydrocarbons will change.  An increase or decrease of only 3eC causes




at least one pair of compounds to elute together.  With an increase in




temperature, cycloparaffins and aromatics are retained on the column




longer relative to paraffins.

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                              -27-




Alkyl benzenes through C
	10




     Determination of alkylbenzenes through CIQ is complicated by the




presence of saturates that accompany the alkyl benzenes from the pre-




fractionator column.  The saturates would elute with the alkylbenzenes




if a column separating compounds in order of the boiling point were




used.  However, interference is minimized by using a polar liquid phase




that selectively retains alkylbenzenes while saturates of similar boil-




ing points are separated first.




     Good separations were obtained with an 800-foot by 0.01-inch




column, coated with polyethylene glycol.  This column has high separating




power for individual alkylbenzenes and is selective in retaining the




alkylbenzene past saturates.  The column is operated at 60°C with a




helium exit flow of 0.20 ml per minute at a gauge pressure of 45 p.s.i.




     To perform the analysis, the double four-way valve is positioned




so helium flows through the prefractionator into the liquid nitrogen




trap.  Helium flow is adjusted to 40 ml per minute.




     The trap is immersed about two inches into liquid nitrogen.  One




to 20 pi of crude oil, which contains about 1.5% of one or more of the




reference standards, is added.  Elution is continued until the desired




components are in the trap; the time needed must be precisely determined




with prior runs.  With this apparatus, four minutes are needed for




elution of components through toluene; 6.5 minutes are needed for




alkylbenzenes through 1, 3-dimethylbenzene; 15 minutes are needed for

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                             -28-




alkylbenzenes through Cg.  Similarly, gasoline and other volatile




components may be analyzed and identified.




    After the desired components have been typed, the position of the




double four-way valve is switched.  Helium pressure to the capillary




column is adjusted.  After equilibrium, current is applied to the




stainless steel trap heater so that its portion of trap outside of




liquid nitrogen reaches 130°C, after which the sample is introduced




into the capillary column by removing the liquid nitrogen.  Three




seconds are required to vaporize the sample.






Results




    Accuracy was estimated by analyzing synthetic blends made to




simulate crude oil and by analyzing crude oils previously examined



with packed columns.  Average deviations from mean values are only



3% relative.






FIA method D 1319-61T (1)




    This older method describes the procedure for the determination




of the saturates, olefins, and aromatics (Including aromatic olefins)



in petroleum fractions that distill below 600°F.   Gasoline is an example.




    About 3/4 ml of sample containing traces of fluorescent dye (Sudan




III) is introduced into a small glass adsorption column of 154 cm X 1.5




mm dimensions.  Silica gel of 100 to 200 mesh size is used.  When all




the sample has been adsorbed on the gel, alcohol is added to desorb




and develop the sample.   The hydrocarbons are separated according to

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                              -29-




their adsorption affinities into aromatics  (including aromatics  with




olefinic side chains plus any sulfur, nitrogen,  and oxygen compound),




olefins, and saturates.  The fluorescent dyes are also selectively




separated with the sample fractions, and mark the boundaries  of  the




aromatics, olefins, and saturates clearly visible under ultraviolet




light.  Ultraviolet light source with radiation  at 3650A0 is  required.




The volume percentage of each hydrocarbon type is determined  by




measuring the length of each zone in the long, narrow extension  of




the column.  Reproducibility for experienced operators is about  3%




for determining aromatics, olefins, and saturates.




     A more defined characterization of the saturated fraction could




be obtained by determination of the naphthenes in the saturated




fraction.  The ASTM D 2002-62T method covers the isolation of sat-




urated hydrocarbons by shaking a measured amount of sample with  a




solution of PO^S *n concentrated H_SO,.  The unreacted hydrocarbons,




when separated, recovered and washed from the sulfonation acid,  are




representative of the saturates in the sample.






Infrared Analyses




     A suitable tool for the identification of heavier petroleum pro-




ducts is the infrared spectrophotometer.  As greases, heavy residual




fuel oil, and asphalt are less volatile, the unknown infrared spectrum




can be compared with the reference spectrum.  If the unknown  has been




exposed unduly to environmental factors, such as air, sunlight,  or

-------
                              -30-




temperature, peroxidative (15) changes are considered.   Useful infor-




mation cannot be obtained from the infrared spectrum of the volatile




petroleum products, such as naphthas and gasoline, unless an on-the-spot




collection is made of the sample immediately following  the spill.




     Though each petroleum product is a mixture of numerous types  of




organic compounds, a peak-by-peak correlation qualitatively and




quantitatively of an unknown sample against that of an  authentic




source sample is excellent evidence for identity.  Certain group




frequency bands permit the chemist to obtain useful information with




reference to known functional group frequencies.  These characteristic




group frequencies may afford partial or complete characterization




(5, 7, 25).




     Infrared spectra may be obtained for gases, liquids, or solids.




Because water sampling normally involves liquids or solids, the dis-




cussion on sample handling will involve the latter two  items.  Liquids




may be examined in solution or neat.  Liquids (neat)  are tested between




plates; the amount of material is several mg.  Mobile liquids may  be




also handled in cells from 0.1 to 1 mm in thickness.  However, when




solutions are used, the selection of solvent is critical.  The spectrum




obtained from examination of a solution should be that  of the solute




except in regions where the solvent absorbs strongly.




     For examining trace amounts of material, microcavity cells are




used with a beam condenser.  The cell may have a path length of 0.05 mm

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                             -31-


 and  a  capacity of 0.8 microliter.  The solvent and sample should be dry


 and  transparent in range of measurement.  Carbon tetrachloride, carbon


 disulfide, and chloroform are the solvents frequently used.  It is


 suggested that solutions analyzed with matched cells be dilute.  Con-


 centrated solutions will render useless the advantage of matched cells.


     Solids are examined as a mull which are prepared by grinding


 several mg of the solid with a drop of Nujol.  This mull is placed


 between two plates as a film.  Solids may also be examined as discs


 made from 1 mg of material mixed, by vibration, with 100 mg of dried

                                                                     o
 potassium bromide.  In a die under pressure of about 30,000 Ib per in


 discs  are pressed.


    Before a sample is examined with a suitable infrared spectrometer,


 the following are required:  (1) the instrument, e.g., Perkin Elmer 137,


 must be calibrated so that the absorption bands of the instrument's


 spectrum coincide with those established for a standard polystyrene


 film;  (2) the sample to be examined should be free of moisture and


 solvents which may interfere with the unknown spectrum.


    The two important areas for a preliminary examination are in the


 region below 7.4y and in the 11.1 to 15.4y region.   Important absorp-


 tion bands are interpreted after what has been observed in the high


 and low energy regions of the spectrum.  The most frequently used band


assignments for petroleum products derived directly from crude oil are


given in Table IV.

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                       -32-
 Table  VI.  Most  Frequently Used Band Assignments





 Paraffins    (s)CH3   (a)CH3   (s)CH3  (a)CH3



             3.38y    3.48v    6.8y   7.28y
             (s)CH2      (a)CH2



             3.42p       3.51u
                                  13.9y
Olefins     O=C    _.      .. _
	            Cis     14.5u

         6.0-6.ly  Trans   10.4y

                   Vinyl   10u, lly
Aromatic    3.23-3.33y   6.2-6.29y; 6.7-6.76y



                                   11.1-15.4p

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                              -33-




     The following functional groups should be considered in the more




complex products, such as chemicals or peroxidized material:  carbonyl,




acidic, ester, ether, peroxido, hydrox/1, sulfoxides, sulfones, sulfides,




phosphates, etc.  Group frequency assignments are found in Bellamy (5)




and other texts on infrared spectroscopy (7, 25).




     To aid in identification, the dried grease is analyzed by infrared




spectrometry and matched with the known or reference sample.  The two




spectra are compared.  A match of peak-by-peak correlation is necessary




for the entire spectrum, unless loss of certain group frequencies occurs




due to solubilization of certain compounds in the aqueous medium or due




to changes effected by the autoxidation process.




     The nearly ash-free residue, after drying, is considered to be




heavy residual fuel oil or asphalt when soluble only in chloroform.




Measurement of the infrared absorbances at six group frequencies is




made.  These are 3050 cm" , 2925 cm~ , 1600 cm"  , 1375 cm" , 810 cm" ,




and 720 cm  .  Absorbances are determined by the base-line technique.




The length of the vertical line, which intersects the line tangential




to the two proximate inflections, is measured.  Ratio of intensity of




the infrared absorption (RIA) at one frequency to that intensity of




the absorption at another frequency is considered.  These ratios are




given in Table VII.

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                  -34-
Table VII.  Ratios of Infrared Absorbances
  of Commercial Asphalts & #6 Fuel Oils (16)
KIA
720 cm'1
1375 cm'1
3050 cm'1
2925 cm"1
810 cm"1
1375 cm'1
810 cm'1
720 cm'1
1600 cm'1
1375 cm"1
1600 cm"1
720 cm"1
Asphalt
.28
.20
.25
.87
.54
1.97
#6 Fuel Oil
.20
.25
.46
2.42
.73
4.18

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                              -35-
 In addition,  the average values of ratios of seven commercial asphalts
 and  #6 fuel oils are given.
     The  #6 fuel oils are  found to contain more aromatics that absorb at
 800  cm    than the asphaltic products, according to the plot of points
 810 cm    versus 810 cm   .  Asphalt ratios are located near the origin
 1375 cm7"1         720 cm'1
 of the plot and have values less than 0.4 for the former ratio and less
 than 1.3  for  the latter ratio.  The heavy residual oils, or #6 fuel oils,
 lie  on the same common line expressed by the equation Y = 0.13 X +0.125.
 In contrast to asphalts, residual oils are characterized by a smaller
 proportion of  carbon methyls and methylene chains.  The absorbance due
 to carbon methyl branching is about four times the absorbance due to
 the  methylene  chains.
     The identity of the classified petroleum product, whether asphalt
 or residual oil, can be established by comparative evaluation of the
 above two ratios.  Further, the identity of the unknown with the known
 is confirmed by comparing the remaining four ratios of the unknown with
 the known.  All values should check.
     Autoxidation (16) of the residual oil in water at ambient temper-
 atures will show increases in the ratios
       -1         -1         -1              1
 1030 cm   . 1155 cm  . 1300 cm" . and 1695 cm" .   These increases that
 1375 cm'1  1375 cm'1  1375 cm'1      1375 cm'1
 occur within one week are due to increase formation of sulfoxides, alkyl
ethers, secondary alcohols, and carbonyls.   These small changes at the
 representative group frequencies should be considered when establishing
 the identity or source of pollutant with a fresh reference sample.

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                              -36-




     A point to consider in the evaluation of the vessels carrying




or using foreign residual fuel oil is that this product normally




contains less cracked stock than domestic fuel.  The reason is that




domestic residual fuel is the product obtained after numerous




catalytic and thermal processes that are responsible for aromaticity




and olefinic formation.  Foreign residual fuel oils are products of




straight-run distillation.  The set of values may form a distinct



linear relationship.






Trace Constituent Analyses




     Many metals are found in trace quantities in petroleum (11).



Some are in solution, some in suspension, and others are associated




or chelated with the porphyrin molecules in petroleum.  Generally,




nickel and vanadium are present in highest quantity.  The crude oil




or residual fuel oil is washed, dry ashed, and analyzed by emission,



absorption spectroscopy or by x-ray fluorescence.




     Ball et al. (2,3) made a comprehensive examination of a California



crude oil containing appreciable quantities of nitrogen, sulfur, and




oxygen.  Concentrated in the asphalt fraction are the nitrogen com-




pounds of high molecular weight.   Small amounts are found in the




distillates.  These are suspected to be pyrroles, indoles, and



carbazoles.




     Of the oxygenated types of compounds, phenols and organic acids




have been isolated.   Investigation in this area will provide an




addition to fundamental knowledge and an aid to economic processing

-------
                              -37-




of the crude.  If one applies a suitable method (13, 14)  of minor




constituent analyses, such information obtained will serve as an




aid to identification.  Types and amounts of acids, phenols, and




mercaptans may serve to identify one crude oil from another.

-------
                            -38-

                  Characterization Scheme
Soluble
Naphthas
Gasoline
Jet fuel
Kerosene
Fuel oil #1
Gas oil
White oil
Motor oil
Fuel oil #2
Fuel oil #4
Wax
 Residue  - Dried

	(hexane)
Insoluble
                                                        #6
                                       Jelly, Grease, Fuel oil/Asphalt
                                    (CHC13)
               Grease
               Metals
               Ba, Li, Ca
               acids
                              Fuel oil
                         Asphalt
               IR - RIA
                                           partly sol.
                                     Jelly
         partly sol.
         in hexane,
         in ether,
         in CHC13

          (IR)
                       Hi aromatic   Lower aromatic
                         #6 Fuel oil    Asphalt
                                    Grease
                                    High
                                    nitrogen
                                    AMIDE-Type

-------
      -39-
Resldue - Dried
Soluble

High gravity naphtha
Gasoline
Low gravity naphtha
Jet fuel
Kerosene
Fuel Oil #1
Gas oil
v.
White oil
Motor oil
Fuel oil #2
Fuel oil #4
Wax
(hexane)
I.B.P.-e.P. API
95° - 206 °F 45
96° - 408°F 58
160° - 410°F 30
100° - 5008F 40
355° - 575°F 40
- gravity
- 75
- 62
- 52
- 55
- 46
360° - 625°F >35
400° - 800 °F 30
29
24
370° - 625°F
(90%)
420° - 683°F 9
MP = 145°-
190°F 34
- 33
- 32
- 30
>26
- 36
- 39
Comment





k. vis.

I.R.-
paraffin
Zn, P, S
k. vis.
k. vis.
Solid-IR
paraffinic

-------
                              -40-

                           REFERENCES

 1.  "ASTM Standards on Petroleum Products  and Lubricants,"  Prepared
     by ASTM Committee D-2 on Petroleum Products  and Lubricants,
     November 1957.  Published by the American Society  for Testing
     and Materials, Philadelphia, Pennsylvania.

 2.  Ball, J. S., Raines, W.  E., and Helm,  R.  V.,  Fifth World
     Petroleum Congress Proceedings. June 1-5, 1959,  Section V,
     Paper 14, p. 175,  Published by Fifth  World  Petroleum
     Congress, Inc. , New York.

 3.  Ball, J. S., Wenger, W.  J., Hyden, H.  J., Horr,  C.  A.,  and Myers,
     A. T., Preprints, Division of Petroleum Chemistry,  American  Chem-
     ical Society, ],, No. 1,  241-6 (1956).

 4.  Belcher, R., "Submicromethods of Organic Analysis," Elsevier
     Publishing Co., New York, 1966, p. 70.

 5.  Bellamy, L.  J., "The Infrared Spectra  of Complex Organic Mole-
     cules," 2nd ed., John Wiley and Sons,  New York,  1958.

 6.  Boyd, G. A., Oil and Gas J.. 32(8).  16,  31 (1933).

 7.  Colthup, N,  B., Daly, L. H., and Wiberly, S.  E., "Introduction
     to Infrared and Raman Spectrescopy," Academic Press, New York,
     1964.

 8.  Dal Nogare,  S. and Juvet, R. S., Jr.,  "Gas Liquid  Chromatography,
     Theory and Practice," Interscience Publishers, New York, 1962.

 9.  Encyclopedia of Science  and Technology,  Volume 10,  p.66, Table 4,
     McGraw-Hill Book Co., Inc.

10.  Fieser, L. F., Experiments in Organic  Chemistry,"  2nd ed.  D. C.
     Health and Company, New  York, 1941,  p. 244.

11.  Gamble, L. W. and Jones, W.  H., Anal.  Chem..  27, 1456 (1955).

12.  Johnson, W.  D. , Kawahara, F. K., Fuller,  F.  D.,  Scarce, L. E.,
     Risley, C.,  Jr., Proceedings of the Eleventh  Conference on Great
     Lakes Research. April 18, 1968.

13.  Kawahara, F. K., Anal. Chem. 40, 1009  (1968).

14.  Kawahara, F. K., ibid.,  40,  2073 (1968).

-------
                              -41-

15.  Kawahara, F. K., Ind. Eng. Chem. Prod. Res. Develop.  4^  7  (1965)

16.  Kawahara, F. K., Environmental Science and Technology, to  be
     published.

17.  Littlewood, A. B., "Gas Chromatography," D. H. Desty, ed.,
     Academic Press., New York, 1958,

18.  Martin, R. L. and Grant, J. A., Anal. Chem. .  37., 644  (1965).

19.  Martin, R. L. and Winters, J. C., Anal. Chem.. 31,  1954  (1959).

20.  Martin, R. L. and Winters, J. C., ibid, 35_, 1930 (1963).

21.  McElvain, S. M., "The Characterization of Organic  Compounds,"
     The MacMillan Company, New York, 1945, pp.  36-37.

22.  Morton, A. A., "Laboratory Technique in Organic Chemistry,"
     1st. ed., McGraw-Hill Book Company, Inc., New York, 1938,
     p. 110.

23.  Nelson, W. L., "Petroleum Refining Engineering," McGraw-Hill
     Book Company, Inc., New York, 1958, p. 143.

24.  Sanders, W. N. and Maynard, J. B. , Anal. Chem. . 40_, 527  (1968).

25.  Silverstein, R. M., and Bassler, G. C., "Spectrometric Identi-
     fication of Organic Compounds," John Wiley  and Sons,  Inc., New
     York, 1964, pp. 49-70.
                                               US GOVERNMENT PRINTING OFFICE. 1973- 759-S5Z/10B1

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