Preparation method of catalyst for acrylonitrile fluid bed

Abstract

The invention relates to a catalyst used in acrylonitrile manufacture. The method for preparing the catalyst comprises the processing steps of spray molding, pyrolysis, crystalling phase conversion, and activation roast, and is characterized in that template agent is added in a carrier at first, and the template agent is at least one of tetraethylammonium, tetrapropylammoniumsilicate, polyacrylamide and ethylsilicate; active components are added in the mixing material above mentioned, and the pH value is controlled between 1.5 and 2.5; the mixture is aged before spray molding, the aging temperature ranges from 60 to 120 DEG C, the operating pressure ranges from 0.01 to 0.8Mpa, and the aging time is 1 to 10 hours; the catalyst prepared according to the proposal contains a silicon dioxide carrier and a combination, the chemical formula of which is AaBbCcDdMgeNifBigFehMoiOx calculated on the basis of atomic ratio, wherein, the chemical formula can include Li, K, Cs, Rb, As, B, P, Se, Cu,Sn, Ga, Sr, Ba, Ce, Cr, V, Sb, La and Co. The catalyst has good activity, selectivity, anti-reducibility, and abrasion resistance and can be used in a reactor form a long time, and the service life can even reach more than three years.

Description

technical field [0001] The present invention relates to a catalyst, and more particularly to a catalyst for the production of acrylonitrile. Background technique [0002] Acrylonitrile is one of the important petrochemical products, mainly used in the manufacture of acrylic fibers. The Sohio method is widely used in the world to produce acrylonitrile by ammoxidation of propylene. The key technology in this process is the preparation of fluidized bed catalyst in the reactor. For the research on acrylonitrile fluidized bed catalyst, most of the research in our country is currently focused on the composition of chemical components, research on the application of high molybdenum active components, fine particle size in supplementary catalysts, research on α-molybdenum-bismuth-iron and γ-molybdenum The bismuth-iron system affects the yield of acrylonitrile. In the actual production and use process, it is found that some catalysts have high activity in the initial stage, and afte...

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Problems solved by technology

[0008] In the above studies, the acrylonitrile catalysts were all produced by the traditional process. The nitrate, carrier silica and ammonium molybdate were made into a slurry, spray-dried, activated and roasted to obtain an acrylonitrile fluidized bed catalyst. There is no analysis of the state of the carrier, how the active components are distributed between the carriers, and there is no disclosure of the activity, selectivity, reduction resistance, long-term stability, etc. Research results

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