Microspherical ethylene oxychlorination catalyst preparation method

Abstract

The invention discloses a microspherical ethylene oxychlorination catalyst preparation method, which comprises the following six steps: solution preparation; precipitation and reaction; peptization; active component and assistant component homogenization; spray forming; and post-treatment. Solution of an active component and solution of an assistant component are dissolved in peptized pulp; a proper amount of dispersant and pore-expanding agent are added into the pulped sol solution to ensure the active component and the assistant component are uniformly distributed in the sol solution; the dispersant can prevent active and assistant component deposition caused by the prolongation of spray time; and the added proper amount of pore expanding agent can expand formed pore passage with a microspherical structure in a spraying process of the sol solution so as to improve the volume of the pore passage of a catalyst carrier and improve the pore volume and specific area of the catalyst.

Description

technical field [0001] The invention relates to a preparation method of an ethylene oxychlorination catalyst. Background technique [0002] Polyvinyl chloride (PVC) is one of the five general-purpose resins. It has the outstanding characteristics of rich raw materials, mature manufacturing technology, low price, and wide application. It has become the second largest general-purpose resin in the world after polyethylene resin. PVC is easy to process, and can be processed by molding, lamination, injection molding, extrusion, calendering, blow molding, etc., so it is widely used in the production of soft plastic products such as artificial leather, film, and wire sheaths, as well as in the production of panels, doors and windows. , pipes and valves and other hard plastic products. [0003] Polyvinyl chloride is polymerized from vinyl chloride (VCM) monomer. Vinyl chloride is an important organic chemical raw material with a large tonnage. Most of it is used to produce polyviny...

AI Technical Summary

Problems solved by technology

[0009] The first technical problem to be solved by the present invention is that in the prior art, the ethylene oxychlorination catalyst adopts the co-precipitation method to prepare the alumina microsphere carrier containing the main active component, and then uses the impregnation method to realize the oxidation of other auxiliary active components. The loading on the aluminum microsphere carrier, the preparation method adopts the follow-up independent impregnation method to easily lead to the uneven dispersion of the active component on the carrier, thereby affecting the catalytic activity of the catalyst, and then provides a method that can be used in the preparation of alumina microspheres In the process of carrier, the uniform loading of main active component and auxiliary active component is realized at the same time, and the method of preparing ethylene oxychlorination catalyst by coupling coprecipitation method and impregnation method

[0010] The second technical problem to be solved by the present invention is that in the process of preparing the ethylene oxychlorination catalyst in combination with the coprecipitation method and the impregnation method in the prior art, when the copper-containing alumina carrier microspheres are prepared by the coprecipitation method, water is used to The co-precipitate is slurried and spray-dried to shape, and the prolongation of the spraying time will easily lead to uneven dispersion and deposition of active substances in the slurry after slurry, resulting in uneven distribution of active substances on the formed alumina carrier microspheres. problem, and further provide a method for preparing an ethylene oxychlorination catalyst that can achieve uniform dispersion of the precipitate after slurrying and spray drying and can be evenly distributed on the alumina carrier

[0011] The third problem to be solved by the present invention is that in the process of preparing the ethylene oxychlorination catalyst by combining the co-precipitation method and the impregnation method in the prior art, the alumina carrier prepared by using the co-precipitation method combined with the spray drying molding technology has a micro The pore structure of the ball is relatively dense, the pore is narrow, and the active component is not easy to fully enter the inside of the microsphere pore, so that the effective specific surface area of ​​the catalyst is reduced, and the impregnated active component is easily exposed to high temperature during subsequent use. Sublimated and lost, thus affecting the catalytic activity and catalytic selectivity of the catalyst, and then providing a microsphere structure expansion of the alumina carrier, and improving the effective specific surface area of ​​the catalyst and the catalytic activity and selectivity of the ethylene oxide The preparation method of chlorination catalyst

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