Dehydrogenation catalyst and application thereof in preparation of divinylbenzene by dehydrogenation of diethylbenzene

Abstract

The invention belongs to the field of catalytic chemistry, and particularly relates to a dehydrogenation catalyst and application thereof in preparation of divinylbenzene through dehydrogenation of diethylbenzene. The catalyst is prepared from the following components in parts by weight: 20 to 40 parts of lanthanide modified heteropolyacid salt, 10 to 20 parts of macroporous cross-linked polymer loaded nano alpha-Fe2O3, and 40-70 parts of one or more of oxides of CeO2, MnO2, ZrO2 and WO3. The supported catalyst is applied to a diethylbenzene dehydrogenation reaction, and product distribution can be effectively optimized by adjusting components in heteropolyacid salt. Water vapor is not needed in the reaction process, the reaction rate is high, selectivity is high, product system separationis simple, the technological process is safe and environmentally friendly, and industrial production is facilitated.

Description

technical field [0001] The invention belongs to the field of catalytic chemistry, in particular to a dehydrogenation catalyst and its application in the dehydrogenation of diethylbenzene to prepare divinylbenzene. Background technique [0002] In recent years, with the rapid development of polymer materials, divinylbenzene, as a functional monomer, has been expanding its application fields. The divinylbenzene molecule contains two vinyl groups, forming three isomers: ortho, meta, and para. Refining divinylbenzene, increasing the content of intermediate and para-body in the mixture, and obtaining products with different purity levels have become the main controlling factors of market price. Low-purity divinylbenzene can be directly used as a functional chemical crosslinking agent, widely used in adhesives, professional plastics, and elastomers. Divinylbenzene and styrene are cross-linked and polymerized to produce ion-exchange resins, and are also used for modification of p...

AI Technical Summary

Problems solved by technology

The purity level of divinylbenzene is affected, which seriously restricts its application in high-end optical materials

In addition, this traditional dehydrogenation process uses iron oxide as the main catalyst, which has outstanding problems such as low single-pass conversion and low product selectivity.

In actual production, the induction period of the catalyst is long, and the phenomenon of catalytic efficiency reduction and surface coking are prone to occur in the middle and late stages of production. During the reaction, a large amount of water vapor needs to be continuously added to regenerate the catalyst, resulting in high energy consumption.

[0004]Patent CN1915941 discloses the addition of rare earth element compounds in the Fe–K–Ce–Mo catalytic system to catalyze the dehydrogenation of diethylbenzene, and the catalyst has a high ability to resist carbon deposition , but the selectivity of the by-product ethyl styrene is higher

Patent CN10779282A discloses a kind of containing Fe2O3, K2O, CeO2, MoO3, CaO, Na2O and other components selected from MnO2, TiO2, Pr2 O3 At least one or several composite catalysts are used for the dehydrogenation of diethylbenzene, and the resulting product has the characteristics of low monodiene ratio, but the reaction temperature is relatively high , and water vapor must be added to regenerate the catalyst

[0005] The catalytic performance of the existing production process does not match the production requirements and product quality, which has become a development bottleneck and technical barrier for the production of highly selective divinylbenzene

Images