Catalystic hydrogenation and dechlorination catalyst for preparing trifluorochloroethylene and trichloroethylene

Abstract

A catalyst for hydrogenation and dechlorination to prepare trifluorochloroethylene and trichloroethylene has noble metal Ru and metal Cu as main active components, La-enriched RE mixture and alkali metal Li as modifying assistants and active coconut charcoal and carrier. It has excellent comprehensive reaction performance, including reaction activity, selectivity, service life, etc. as well as relative low cost.

Description

1. Technical field: [0001] The invention relates to a catalyst used in the technical process of preparing chlorotrifluoroethylene and trifluoroethylene from 1.1.2-trifluoro-1.2.2-trichloroethane. 2. Background technology: [0002] Chlorotrifluoroethylene and trifluoroethylene are important monomer raw materials for preparing many fluorine-containing chlorine or fluorine-containing polymers (homopolymer or copolymer). Chlorotrifluoroethylene is also the main raw material of a fluorocarbon coating that can be solidified and formed into a film at room temperature; trifluoroethylene is an important finishing agent for high-grade pure cotton fabrics and a raw material for the environmentally friendly refrigerant HFC-134a. The most commonly used industrial production method for preparing chlorotrifluoroethylene monomer is the process of quantitative chemical reduction dechlorination of trifluorotrichloroethane (commonly known as F113) and metal zinc powder; however, it is impossib...

AI Technical Summary

Problems solved by technology

Although the reaction conditions of the metal zinc powder dechlorination method are milder (about 100°C of reaction temperature and about 1.0Mpa of operating pressure), the production process can only be batch operation; Far beyond the theoretical value, and also need to use a large amount of solvent methanol or ethanol etc., thus make the production cost of product chlorotrifluoroethylene higher; Vinyl chloride will produce about 1.3 tons of zinc chloride waste residue) which is difficult to handle and brings serious environmental pollution problems

[0003] In the past work of catalytic hydrodechlorination of chlorotrifluoroethylene, a mixture of metal oxides such as non-noble metal copper, chromium, nickel, barium, and calcium is used as a catalyst (such as U.S.P., 3,333,011 (1967) and J.P., Zhao 64-29328(1989)); or metal nickel loaded on SiO 2 AL 2 o 3 Or the catalyst (such as J.P., flat 5-9138 and E.P., 0416,015A1 (1990)) made on active carbon, the deficiency of this type of catalyst is that required reaction temperature is too high (400-500 ℃) and catalyst life-span is shorter ; And there are precious metals mainly palladium and platinum supported on activated carbon, SiO 2 or AL 2 o 3 The above is catalyst (such as E.P., 0459,463 (1991)) and CN 065261A (1992)), the selectivity of this type of catalyst activity and chlorotrifluoroethylene is relatively high, and the reaction temperature only needs about 240-250 ℃, but , the raw materials palladium and platinum they use are expensive, which will also cause the cost of chlorotrifluoroethylene produced in the reaction process to be too high