The scientific name of Freon refrigerants is halocarbon refrigerants, also known as halocarbons refrigerants. It is the general term of halogenated derivatives of saturated hydrocarbons. It is a kind of refrigerants emerging with the development of chemical industry in the 1930s. Its emergence solves the search for refrigerants in the refrigeration air conditioning field. From the definition of freon, we can see that the non Freon R134a, R410A and R407C are actually Freon.

  the Freon refrigerants used in refrigeration and air conditioning industry in China are R11, R12, R22, R32, R113, R114, r115, R123, R125, R134a, r143a, R141b, R142b, r152, R404A (44% R125, 52% r143a and 4% 134a), R407C (23% R32 and 25% R125 and 52% R134a), R410A (50% R32 and 50% R125), R500 (73.8% R12 and 26.2% r152), R502 (48.8% R22 and 51.2% r115), etc.

   Freon can destroy the ozone layer because of the existence of CL in the refrigerant, and with the increase of the amount of Cl, the destruction ability of the ozone layer increases, and with the increase of the content of H element, the destruction ability of the ozone layer decreases; the greenhouse effect is mainly due to the generation of a large number of greenhouse gases, such as CO2, in the process of slow oxidation and decomposition of refrigerants. According to the structure of Freon refrigerants, they can be roughly divided into the following three categories:

   the first category is chlorofluorocarbons: mainly including R11, R12, R113, R114, r115, R500, R502, etc., which are listed as a class of controlled substances by the Montreal protocol due to their great destructive effect on the ozone layer. The use of such substances has been banned at present, and R11 has been used as a transitional substitute by R141b in the process of making polyurethane sponge.

   the second category is hydrochlorofluorocarbons: mainly including R22, R123, R141b, R142b, etc., and the ozone layer destruction coefficient is only a few percent of R11. Therefore, the second group of substances is considered as a very important transitional substitute for the first group of substances. In the Montreal Protocol, R22 is eliminated by 2020, R123 by 2030, and developing countries can postpone it by 10 years.

  the third category is hydrofluorocarbons: mainly including R134a, R12, lt32, R407C, R410A, r152, etc. the ozone layer destruction coefficient is 0, but the potential value of climate warming is very high. In the Kyoto Protocol, there is no time limit for the use of greenhouse gases in the United Nations Convention on climate change.

  almost all refrigerants used in China are Freon products. So far, no Freon refrigerants have been developed. Before the development of new refrigerants, what we need to solve is which kind of refrigerants should be selected for air conditioning units, which will cause less damage to the environment that our country depends on. It is the first kind of products that should be banned in China, not the second and third kinds of refrigerants.