A kind of preparation method of solid-phase mercury-free catalyst for vinyl chloride synthesis

Abstract

The invention provides a method for preparing a solid-phase mercury-free catalyst for synthesis of vinyl chloride. The method comprises preparation of activated carbon and preparation of an adsorbent,and the preparation of the activated carbon includes pretreatment of raw materials, wherein the pretreatment of the raw materials comprises the steps of: grinding fly ash to a particle size of 1.6-2.0 mum, then mixing the ground fly ash with wood vinegar liquid and coal tar according to a mass ratio of 1:1:1.2, heating the mixture of the fly ash, wood vinegar and coal tar to 87-89 DEG C, adding silica, sodium thiocyanate and tapioca flour, and performing even stirring to obtain a mixture; the preparation of the adsorbent comprises the steps of: mixing an active component and an accelerator ata mass ratio of 2:1, and performing dry grinding under the protection of nitrogen for 6-6.5 hours to obtain adsorbent powder with a fineness of 800-900 meshes. Through the method for preparing the solid-phase mercury-free catalyst for synthesis of vinyl chloride, the catalytic activity of the mercury-free catalyst can be improved greatly, and the loss rate of the active component can be reduced.

Description

technical field [0001] The invention relates to a preparation method of a solid-phase mercury-free catalyst used for the synthesis of vinyl chloride, belonging to the technical field of fine chemistry. Background technique [0002] At present, the industrial production of vinyl chloride monomer in the world is mainly based on the ethylene method. Affected by the large fluctuations in crude oil prices, the production of PVC from acetylene through hydrochlorination occupies an important position in China. At present, the industrial acetylene hydrochlorination reaction mainly uses high-mercury catalysts with a loading of mercuric chloride of 12% to 15%, followed by low-mercury catalysts with a loading of mercuric chloride of 4% to 6%. Mercury consumption accounts for about 60% of domestic mercury consumption, and causes serious harm to the environment and human health. In view of the scarcity of mercury resources and the pollution of the environment, as well as the increasing...

AI Technical Summary

Problems solved by technology

[0003] At present, most of the research on mercury-free catalysts is immature, and there are defects such as high reaction temperature, low catalytic activity, high loss rate, and low vinyl chloride selectivity.