What characteristics are used to select the refrigerant components?

Principles for selecting refrigerants: (1) It should not cause damage to the human ecological environment. It does not damage the atmospheric ozone layer and does not cause a greenhouse effect. (2) The critical temperature is relatively high. It can be liquefied at room temperature or under normal low temperatures. It is hoped that the critical temperature will be much higher than the ambient temperature, in order to reduce the throttling losses of the refrigerant and improve the economic efficiency of the cycle. (3) It shall have an appropriate saturated vapor pressure within the operating temperature range; the evaporation pressure must not be lower than atmospheric pressure to prevent external air from entering the system ； The condensing pressure should not be too high, as this will lead to increased power consumption by the compressor. It also requires the system to have a high pressure resistance, thereby increasing the cost of the equipment. (4) High cooling capacity per unit volume. It can reduce the gas flow rate of the compressor. (5) Low viscosity and density. Reduce flow resistance losses in the system. (6) High thermal conductivity. It can increase the heat transfer coefficient of the heat exchanger, reduce the heat transfer area of the heat exchange equipment, and decrease material consumption. (7) It does not burn, explode, or is toxic. It does not corrode metal materials, has no chemical reaction with lubricating oils, and does not decompose at high temperatures. (8) The isentropic exponent is small. It can reduce the exhaust temperature, decrease the work required during the compression process, and is beneficial for safe operation and extended service life. (9) Low solidification temperature. Avoid solidification at the evaporation temperature. (10) It has good insulation properties. (11) Low price and easy to obtain. (12) The compression work per unit volume is low. To date, no refrigerant that fully meets all twelve of the above requirements has been found. However, when making a choice, comprehensive considerations such as usage conditions can be taken into account

The choice is based on physical properties, and the components and proportions vary depending on your liquefaction device. If you have any specific questions, feel free to ask me directly.

It has stable physicochemical properties, is non-corrosive, has a low price, and is easily available