Hi everybody,
I would appreciate it a lot if some one
has any information on alternative refregrents, i.e.,
alternative to freon. I know of methyl chloride as being
used as refregrent, but I was wondering if there are any
other compounds.
Thanks in advance for your help,
Jasmail Singh
With regard to refrigerants and alternatives to fluorocarbons, there
are many alternatives, though none combine the low flammability,
low toxicity, and chemical inertness of the various fluorocarbon products
(such as Freon).
The National Refrigeration Safety Code Group divides refrigerants
into three categories: Group I (safest), Group II (toxic and somewhat
flammable), and Group III (very flammable).
Group I contains all of the fluorocarbons, plus methylene chloride
and carbon dioxide. Methylene chloride has been used in some
home refrigerators and air conditioning equipment. Carbon dioxide
is generally undesirable because of the high operating pressure it
requires, although it has seen some use on ships due to the small
physical size of the equipment.
Group II contains dichloroethylene, methyl formate, ethyl chloride,
sulfur dioxide, methyl chloride, and ammonia. Methyl formate was
used in a line of GE home refrigerators many years ago. Sulfur
dioxide once was the dominant technology for home refrigeration,
but has since disappeared. It is very irritating to the lungs.
Ethyl chloride and methyl chloride have also been used in some
models, and have likewise disappeared. Both gases are about as toxic
as carbon tetrachloride (i.e. not nice). Ammonia was at one time
used in home refrigerators and is still commonly used, especially in
large plants like fish processing plants and for systems powered by
natural gas (used where electricity is not available). If there is a
little water in the system, ammonia will attack copper, bronze, or
brass components. It is very irritating to the lungs.
Group III contains butane, iso-butane, propane, ethane, ethylene,
and methane. All of these gases are quite flammable, but well-
behaved with regard to toxicity, corrosiveness, and lubrication.
Isobutane has been used in home refrigerators.
Although Freon has been the dominant home refrigerant for many
years, it would not be a disaster to lose this technology. It would be
like losing PCB electrical insulating oils was. It was a nuisance, but
other oils were available that had similar properties. Likewise, there
exist several refrigerants besides Freon which are acceptable
replacements for Freon. Once Freon is eliminated, we might expect
a few deaths due to fire or toxic effects that we would not get
otherwise. For example, a common refrigerator-related accident
is due to the use of a knife to defrost a freezer. If the knife slips
and pierces the freezer coils, the refrigerant will be released. Future
refrigerators may need to be more secure against this type of
accident.
In article <72…@cup.portal.com>, m…@cup.portal.com (Mark Robert Thorson) writes:
> With regard to refrigerants and alternatives to fluorocarbons, there
> are many alternatives, though none combine the low flammability,
> low toxicity, and chemical inertness of the various fluorocarbon products
> (such as Freon).
[Discussion of alternative refrigerants deleted]
At the Organic Reactions Catalysis Society meeting last spring a paper
was presented by Leo Manzer of DuPont on their work on developing an
alternative to chlorofluorocarbon refrigerants. Interest centers on
HFC-134a, CF3CFH2. Contains no chlorine. Targeted for the 1994-1996
time frame for phaseout of chlorofluorocarbons.
–
–Electric Monk (Bruce Gaede);
e-mail: bjg…@ccmail.monsanto.com
"…and then time started seriously to pass."
–Douglas Adams, _Dirk Gently’s Holistic Detective Agency_
- Hide quoted text — Show quoted text -
In article <1992Dec22.07414…@bb1t.monsanto.com> bjg…@bb1t.monsanto.com writes:
>In article <72…@cup.portal.com>, m…@cup.portal.com (Mark Robert Thorson) writes:
>> With regard to refrigerants and alternatives to fluorocarbons, there
>> are many alternatives, though none combine the low flammability,
>> low toxicity, and chemical inertness of the various fluorocarbon products
>> (such as Freon).
>[Discussion of alternative refrigerants deleted]
>At the Organic Reactions Catalysis Society meeting last spring a paper
>was presented by Leo Manzer of DuPont on their work on developing an
>alternative to chlorofluorocarbon refrigerants. Interest centers on
>HFC-134a, CF3CFH2. Contains no chlorine. Targeted for the 1994-1996
>time frame for phaseout of chlorofluorocarbons.
>–
>–Electric Monk (Bruce Gaede);
> e-mail: bjg…@ccmail.monsanto.com
>"…and then time started seriously to pass."
>–Douglas Adams, _Dirk Gently’s Holistic Detective Agency_
R-134a needs new equipment to run. It is not miscible in R-12
mineral oils. The PAG or Ester based oils used in R-134a equipment
are destroyed by the slightest traces of refrigerants with chlorine
(R-12 or R-22). R-134a has been found to cause testicle tumors in
Rats at 5% conc. PAFT (program for Alternate Fluorocarbon Toxicity
tests) released last Sept.
Conferences have pointed out that attempts to "clean out" R-12 (CFC-12)
equipment in order to convert it to R-134a have generally not
worked very well. The few molecules of chlorides embedded in pipe
walls, etc, still come back and start the breakdown of the lubricants.
–ghg
In article <1992Dec22.07414…@bb1t.monsanto.com> bjg…@bb1t.monsanto.com writes:
>At the Organic Reactions Catalysis Society meeting last spring a paper
>was presented by Leo Manzer of DuPont on their work on developing an
>alternative to chlorofluorocarbon refrigerants. Interest centers on
>HFC-134a, CF3CFH2. Contains no chlorine. Targeted for the 1994-1996
>time frame for phaseout of chlorofluorocarbons.
I have contacted DuPont and Bayer on that topic, since we are
*strongly* interested in drop-in replacements for CFCs
From what I heard I understand that the acute toxicity as well as the
subacute long-term toxicity is too high to allow HFC-134a to be used
in industrial processes.
If anybody has different information on that, I really would be happy
to hear more about it.
Alexander
__________________________________________________________________
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| "Only the narrow-minded worry about typos" |
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|________________________________________________________________|
ahgra…@apgea.army.mil (Alexander H. Grabowski <ahgrabow>) writes:
>From what I heard I understand that the acute toxicity as well as the
>subacute long-term toxicity is too high to allow HFC-134a to be used
>in industrial processes.
Probably true. Still to be determined. The PAG-based oil is also nasty.
>If anybody has different information on that, I really would be happy
>to hear more about it.
DuPont has a sorta-replacement for R-12 on the market called SUVA MP-52.
It is not a drop-in because the oils are not compatable. System
flushing is required.
George Goble, g…@ecn.purdue.edu, who has posted in this thread and
is too bashful to blow his own horn, has developed and patented a
drop-in, 100% compatable, non-flammable replacement for R-12. His product,
called "GHG R-12 substitute", abbreviated by me to GHG-12, is compatible
with R-12, can be mixed with R-12 in any proportion and increases the
cooling capacity of the target system from about 20 to 60%. It has
an ODP factor of 0.05 and is on EPA’s "tentative OK" list.
I have been involved in this project as a tester and a cheer leader for
a couple of years. GHG-12 is successfully been running in several
hundred vehicles. There have been only 2 or 3 "failures", only one
of which is attributed to the refrigerant. This was on one of my
systems where an O-ring blew out after installation. The system in
question is over 20 years old and contained a replacement O-ring of
unknown vintage and parentage so the blame does not really belong on
the refrigerant.
A detailed technical article on GHG-12 appears in the free sample edition
of my magazine _Performance Engineering_ (TM). It is available free for
the asking by mailing your postal address to perf…@dixie.com. Do
NOT mail to me at j…@dixie.com asking for samples. My staff handles
the requests; I dump ‘em.
The patent is #5,151,207. George can also be contacted for more
information. GHG-12 and/or a self-sealing version that plugs hose
porosities and small leaks can be orderd from
Monroe Air Tech
800 424 3836
522 West Second St.
Bloomington, IN 47403
812 332 2284 (fax)
John
Claimer: I’m intimately involved in the project and think GHG-12 is
the neatest stuff since sliced bread. Apparently so do a lot of other
folks, judging by the testamonials I’m receiving here at the mag.
—
John De Armond, WD4OQC |Interested in high performance mobility?
Performance Engineering Magazine(TM) | Interested in high tech and computers?
Marietta, Ga | Send ur snail-mail address to
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