Catalyst for synthetizing benzenetetracarboxylic anhydride and preparation method of catalyst

Abstract

The invention discloses a catalyst capable of being used for synthetizing benzenetetracarboxylic anhydride and a preparation method of the catalyst, and belongs to a catalyst technology. The catalyst comprises the main catalytic active components V and Ti; the weight ratio is (0.9 to 0.1) to (0.1 to 0.9); the total mass is 10-50% of that of an inert carrier; the total mass reference of the main catalyst is 1; the component P of a cocatalyst is 0.01-0.3; Nb is 0.01-1; and Sb is 0.01-0.3. The method comprises the following steps of: adding proper ammonium metavanadate to reflux and react in an oxalate solution; adding different cocatalysts and titanium dioxide to steep over the night; spraying prepared turbid liquid to a high-temperature spherical inert carrier; and heating and baking in a muffle furnace to obtain the catalyst. The catalyst disclosed by the invention has the advantages that the prepared material is abundant in source; use of toxic vanadium metal is reduced; the catalyst is used for synthesizing the benzenetetracarboxylic anhydride from durene air in a gas phase oxidation manner, and is good in performance; and the yield of the benzenetetracarboxylic anhydride can be effectively improved.

Description

Technical field [0001] The invention relates to a catalyst for synthesizing pyromellitic dianhydride and a preparation method thereof, and belongs to the technical field of pyromellitic dianhydride synthesis catalysts. Background technique [0002] Pyromellitic dianhydride is an important organic chemical raw material, and its main purpose is to react with diaminodiphenyl ether to synthesize polyimide. Polyimide is a new type of synthetic material with high temperature resistance, radiation resistance, impact resistance and excellent electrical conductivity and mechanical properties. It is widely used in high-end technology sectors such as aerospace and electronics. In addition, pyromellitic dianhydride is also an important raw material for the production of high-quality plasticizers, curing agents and powder matting agents. With the development of the petrochemical industry, the output of C9 and C10 aromatic fractions has increased sharply, providing a large amount of high-qual...

AI Technical Summary

Problems solved by technology

At present, most of the pyromellitic dianhydrides are prepared by using durene as a raw material by air gas-phase oxidation. Since this process is a complex heterogeneous catalytic process, the yield of pyromellitic dianhydride is very low.

The preparation of pyromellitic dianhydride by air gas-phase oxidation of durene mostly uses catalysts with vanadium as the main active component. According to the chemical reaction equation, the theoretical yield of pyromellitic dianhydride should reach 163%, but the traditional preparation The catalyst activity obtained by the method is relatively low, and the highest actual yield of pyromellitic dianhydride can only reach 56% of the theoretical yield