A system and method for preparing pentafluoroethane

Abstract

The invention discloses a system for preparing pentafluoroethane, which comprises a first reactor, a first separating tower, a second reactor, a second separating tower, a condensing tower, a third separating tower, an HCl absorption tower, a fourth separating tower, a liquid-phase water alkali washing system, a light component removal tower, a rectification tower, an extraction tower, a flash tower, an extractant recovery tower, an HCFC-124 recovery light component removal tower, an HFC-134a recovery rectification tower, an HCFC-124 recovery rectification tower, a CFC-115 recovery light component removal tower, a CFC-115 recovery rectification tower and the like. The system only relates to fluoridation reaction. The concentration of the pentafluoroethane product prepared by the system is 99.6% above. A water separator is added to the reaction section of the system, thereby solving the problem of lower conversion rate caused by catalyst deactivation. The hydrochloric acid, HFC-134a and other byproducts generated in the production process of the system can be recovered.

Description

technical field [0001] The invention relates to a system and method for preparing pentafluoroethane, belonging to the field of chemical industry. Background technique [0002] The chemical name of pentafluoroethane is 1,1,1,2,2-pentafluoroethane. It is a fluorocarbon compound that is harmless to the ozone layer. As a refrigerant, it is mainly used in air conditioners, industrial and commercial refrigeration, chillers and other industries. Among them, it is used to prepare binary and ternary mixed refrigerants such as R404A, R407C, R-410A, and R507 to replace R22 and R12. Pentafluoroethane is an important component of environmentally friendly mixed refrigerants such as R-410A. There is a huge room for market development. Pentafluoroethane can also be used as a fire extinguishing agent. [0003] At present, the preparation of pentafluoroethane mainly has the following deficiencies: 1, the preparation process using trichloroethylene as a raw material has a long process route ...

AI Technical Summary

Problems solved by technology

[0003] At present, the preparation of pentafluoroethane mainly has the following deficiencies: 1, the preparation process using trichloroethylene as raw material has a long process route and high raw material cost, and it is necessary to balance the by-product CFC-113 wherein; 2, using tetrafluoroethylene 3. The preparation process of PCE as raw material has high cost of raw material, is difficult to store and transport, and the unit consumption of raw material is high; 3. For the preparation process of tetrachloroethylene as raw material, due to the low conversion rate and selectivity of PCE-catalyzed fluorination reaction, the output reaches The production capacity is less than the original design, there are many by-products, the catalyst is easy to coke and deactivate, and the subsequent separation is very difficult

Images