Freon Prospect Analysis

Freon is non-toxic or low-toxic, non-irritating odor, non-flammable and non-explosive within the working temperature range of the refrigeration cycle, has good thermal stability, low freezing point, and good lubricity to metals, and a small thermal insulation coefficient. low-level distinctive features. As a refrigerant, foaming agent, and cleaning agent, it is widely used in household appliances, foam plastics, daily chemicals, automobiles, fire fighting equipment, and other fields, and it is also the most widely used refrigerant in the world.

As a chemical substance, Freon can be divided into the following three categories according to its molecular formula:

One is chlorofluorocarbon products, referred to as CFC, mainly including R11 (CCL3F), R12 (CCL2F), R113 (CCL2FCCLF2), R114 (CCLF2CCLF2), etc. These Freon molecules contain two or three chlorine atoms (CL2, CL3);

The second is hydrochlorofluorocarbon products, referred to as HCFC, mainly including R22 (CHCLF2), R123 (CHCL2CF3), R142b (CH3CCLF2), etc. These Freon molecules contain one or two chlorine molecules (CL, CL2); Freon R22 is the most widely used Freon refrigerant.

The third is hydrofluorocarbons, referred to as HFC, mainly including R134A (CH2FCF3), R125 (CHF2CF3), R32 (CH2F2), R152 (CH3CHF2), R143A (CH3CF3) and so on. With the need for environmental protection and the development of science and technology, people have successively synthesized and produced refrigerants R404A[R125/R134A/R143A], R410A[R125/R32], R407C[R125/R32/134A], which are mixed with several HFCs. R507A[R125/ R143A] etc. These Freons do not contain chlorine atoms.

After the freon is discharged, it is decomposed under the action of strong ultraviolet rays, and the chlorine atoms released from the decomposition will have a chain reaction with the ozone, continuously destroying the ozone molecules. The more chlorine molecules in Freon, the greater the damage to the ozone layer. Therefore, on September 16, 1987, 24 countries signed the Montreal Protocol on Substances that Deplete the Ozone Layer in Montreal, Canada. As of February 2002, 183 countries have joined the Montreal Protocol.

The agreement will list the chlorofluorocarbons (CFCs for short, such as R12, etc.) that have the greatest effect on ozone layer destruction as a class of controlled substances and prohibit their use; HCFCs (such as R22, etc.) are regarded as the most important CFC substances. Important transitional substitute substances, the use of HCFC refrigerants will be banned from 2030; hydrofluorocarbons (HFC) are environmentally friendly refrigerants because they do not contain chlorine molecules, and the ozone layer destruction coefficient is 0. There is no provision in the Montreal Protocol. Therefore, now R134A, R407C, and R410A are widely used in household, automotive air conditioners, and refrigerator refrigeration systems.

Due to its advantages of continuous updating as needed, Freon has formed a rich product category, has good physical and thermal properties, and has continuously expanded its application in food, industrial, civil, aerospace refrigeration, and other refrigeration industries, becoming the refrigerant market. indispensable important member.