United States
Environmental Protection
Agency
Air and Energy Engineering
Research Laboratory
Research Triangle Park, NC 27711
Research and Development
EPA/600/SR-93/158 November 1993
&EPA Project Summary
Investigation of Possible Uses of
Surplus CFC/Halon Chemicals
John Sherwell
This project investigates the possi-
bility of alternate uses for surplus chlo-
rofluorocarbon (CFC)/halon chemicals
as they are replaced in their traditional
service roles. These uses may be ben-
eficial new products or substances that
are nonhazardous to the environment.
Potential transformation technologies
were identified from a study of litera-
ture. The two-carbon-atom (C2) CFCs
and the halons offer the greatest range
of possible products. The possibility of
using existing CFC/halon manufactur-
ing facilities to produce new products
by changing feedstocks is discussed.
Halons are assumed to have no trans-
formation supply since residual demand
for halons in their traditional roles
would consume the entire available
supply. Market supply calculations for
CFCs were based on a number of "what
if" scenarios chosen to represent low,
medium, and high transformation sup-
ply cases. In reality, there is significant
uncertainty in the estimates of CFC sup-
ply for transformation. CFC-12 repre-
sents about 70% of the total
transformation supply bank. An engi-
neering assessment of CFC-12 trans-
formation chemistry is presented.
The study concludes that there is
significant uncertainty in the transfor-
mation supply of CFCs and that no
transformation process offers an im-
mediate, clear, and economically viable
option for CFC transformation.
This Project Summary was developed
by EPA's Air and Energy Engineering
Research Laboratory, Research Triangle
Park, NC, to announce key findings of
the research project that is fully docu-
mented in a separate report of the same
title (see Project Report ordering infor-
mation at back).
Overview
This project investigated the possibility
of alternate uses for surplus chlorofluoro-
carbon (CFC)/halon chemicals as they are
replaced in their traditional service roles.
These uses may be beneficial new prod-
ucts or substances that are nonhazardous
to the environment. The CFC/halons in-
vestigated in this study were: CFC-11,
HCFC-22, CFC-114, R-500, Halon-1211,
Halon-2402, CFC-12, CFC-113, CFC-115,
R-502, and Halon-1301.
This study emphasized the U.S. mar-
ket; however, where data were available,
global estimates were sought.
The study had three major components:
(1) Identification of potential transfor-
mation technologies.
(2) Identification of potential U.S. mar-
kets for transformation.
(3) Engineering evaluation of the trans-
formation technologies.
The potential transformation technolo-
gies were identified from a study of re-
ports in the literature of chemical reactions
involving the targeted CFC/halons. A wide
variety of reaction types are reviewed, with
the C2 CFCs and the halons offering the
greatest range of possible products. In
general, any transformation process will
require a fairly pure feedstock. The possi
bility of using existing CFC/halon manu
facturing facilities to produce new products
by changing feedstocks is discussed. Dif
ficulties relating to product separation are
specially noted.
Printed on Recycled Paper
-------
The market supply for transformation
was assumed to include recoverable and
newly made CFC/halons. The manufac-
ture of CFC/halons specifically for trans-
formation was not considered. A recent
United Nations Environment Program
(UNEP) report had indicated that, in the
absence of a prohibition on use (as op-
posed to manufacture), residual demand
for halons in their traditional roles would
consume the entire available supply.
Halons are assumed to have no transfor-
mation supply. Data on projected future
end uses of the various CFCs were not
available; consequently, market supply
calculations are based on a number of
"what if" scenarios. These were chosen to
represent low, medium, and high transfor-
mation supply cases. In reality, there is
significant uncertainty in the estimates of
CFC supply for transformation. The distri-
bution of the CFC types shows CFC-12 to
have the largest potential transformation
supply: it represents about 70% of the
total bank.
An engineering assessment of CFC-12
transformation chemistry is presented. In
a pyrolysis reaction with methane, CFC-
12 is converted to vinylidene fluoride, the
monomer for poly (vinylidene fluoride) pro-
duction. This monomer is currently pro-
duced via a d-fferent route. However, there
is an expanding demand for the polymer
The process may have an add-on appli
cation in developing countries where CFC
12 production is in place. For the process
to be a commercial success, it is probable
that some process optimization will have
to be undertaken, especially in the area of
product separation.
The significant observations in the study
were:
There is significant uncertainty in
the transformation supply of CFCs
No transformation process offers an
immediate, clear, and economically
viable option for CFC transforma
tion.
John Sherwell is with Radian Corp., Austin, TX 78720.
Dale L. Harmon is the EPA Project Officer (see below).
The complete report, entitled "Investigation of Possible Uses of Surplus CFC/
Halon Chemicals," (Order No. PB93-229771; Cost: $27 00; subject to change)
will be available only from:
National Technical Information Service
5285 Port Royal Road
Springfield, VA 22161
Telephone: 703-487-4650
The EPA Project Officer can be contacted at:
Air and Energy Engineering Research Laboratory
U.S. Environmental Protection Agency
Research Triangle Park, NC 27711
'U.S. Government Printing Office: 1993 — 550-067/80118
United States
Environmental Protection Agency
Center for Environmental Research Information
Cincinnati, OH 45268
Official Business
Penalty for Private Use
$300
BULK RATE
POSTAGE & FEES PAID
EPA
PERMIT No. G-35
EPA/600/SR-93/158
------- |