Supported catalyst comprising pseudo-boehmite and γ-Al2O3, its production and use for 1,2-dichloromethane production

摘要

A process for preparing 1,2-dichloroethane by reacting about 2 mols of ethylene, about 4 mols of hydrogen chloride and about 1 mol of oxygen in the presence of a fixed bed of supported catalyst based on copper(II) chloride in only one reaction zone at a pressure of from 2 to 10 bar and at from 220 to 280° C., separating off 1,2-dichloroethane and water from the reaction mixture emerging from the reaction zone and passing most of the exhaust gas back into the reaction zone, where, prior to entry into the reaction zone, the exhaust gas is mixed with ethylene, hydrogen chloride and oxygen, and the oxygen content of the mixture does not exceed 7% by volume, and where the ethylene content of the gas mixture entering into the reaction zone is regulated so that the exhaust gas comprises less than 20% by volume of ethylene, where the supported catalyst used is obtained by tableting a mixture of pseudoboehmite and gamma-Al2O3 in a weight ratio from 4:1 to 1:4, if desired with addition of tableting auxiliaries, loading this support with the active components by saturating with a CuCl2/KCl solution so that the copper content is from 1 to 15% by weight and the potassium content is from 0.1 to 8% by weight, based in each case on the total weight of the catalyst, and then drying the catalyst at from 60 to 400° C.