Preparation method and application of nano-sheet vanadium phosphorus oxygen catalyst with enhanced microscopic mixing and reaction

Abstract

The invention discloses a method for preparing a nano-sheet vanadium-phosphorus-oxygen catalyst that strengthens microscopic mixing and reaction, including the following steps: S1, V 2 o 5 Dissolving and reducing reaction in the first stirred tank; S2, supergravity enhanced phosphoric acid mixed and reacted with the tetravalent vanadium suspension in step S1; S3, after the aging of the second stirred tank, the suspension was subjected to suction filtration to obtain The filter slurry is repeatedly washed with ethanol for 2-4 times, and then the filter cake is dried and activated to obtain a nano-sheet vanadium-phosphorus-oxygen catalyst; the resulting filtrate is collected; S4, the filtrate is separated with a high-gravity rectification device; The liquid material at the bottom of the tower is directly transported to the first stirred tank for recycling after being mixed with fresh solvent. The present invention peels off the micron-scale flower-like stacking morphology of the traditional VPO catalyst into a nano-sheet structure by means of supergravity.

Description

technical field [0001] The invention relates to the technical field of catalyst preparation. More specifically, it relates to a preparation method and application of a nano-sheet vanadium-phosphorus-oxygen catalyst that strengthens microscopic mixing and reaction. Background technique [0002] Maleic anhydride (MA) is an important organic chemical raw material and fine chemical product, which has a wide range of applications and a huge market demand. At present, the industrial production of maleic anhydride is mainly based on the oxidation of benzene and n-butane. Compared with the traditional benzene method, the n-butane oxidation method has the following irreplaceable advantages: the raw material energy consumption of the n-butane oxidation method is small, and the theoretical yield of maleic anhydride is high. 1.1 tons of butane feed gas can produce about 1 ton of MA, and the theoretical output is as high as 1:1.69 (raw material / maleic anhydride), while the benzene oxid...

AI Technical Summary

Problems solved by technology

However, the maleic anhydride production technology in my country is still dominated by the benzene oxidation method with high pollution, high cost, and low product yield, and the production capacity occupancy rate of the n-butane oxidation method is less than 40% (according to statistics, it was 37.2% in 2018)

The comparison of the catalysts prepared by the two methods shows that the catalyst prepared by the former has good crystallinity and can generate α-(VO) with an approximate ideal structure. 2 P 2 o 7 phase, the structure is stable, and there are few deep oxides formed, but the specific surface area is less than 10m 2 / g, there are defects of low reaction rate and high reaction temperature; the catalyst prepared by the latter, when the precursor matrix is ​​generated, the disorder of the solvent molecules increases, and the heterogeneous β-(VO)2P2O7 phase is generated, but the specific surface area is high. 30-60m 2 between / g

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