The Synthesis Of 2-Ethylanthraquinone Over Modified ? Catalysts

2-Ethylanthraquinone (2-EAQ) is an important intermediate for the synthesis of hydrogen peroxide and dyes. With the increasing demands for hydrogen peroxide in the international market, it needs to increase the production of 2-EAQ. The traditional manufacture process of 2-EAQ consists of two reaction steps:The second step is the dehydration of 2-(4'-ethylbenzoyl) benzoic acid (BE acid), which commonly catalyzed by concentrated H2SO4 or oleum. In the traditional process, a large amount of waste acid is generated, which hazards to environments, human being and production system.In the paper, the dehydration of BE acid into 2-EAQ over zeolite catalyst, including H-? and different liquor modified H-? catalysts, was carried out. A modified H-? zeolite shows the best catalytic performance with a conversion to BEA as high as 98.5% and a selectivity to 2-EAQ as high as 98.9%. These results lay a theoretical foundation for the industrial production of 2-EAQ. In our study we come to the following conclusion:1 Intercrystalline pore produced from the accumulation of nanoparticles enhanced the catalytic activity due to their diffusion limitation being solved.2 Through boric acid aqueous solution treatment, the as-prepared H-? exhibited lower weak acid contents and stronger weak acid intensity. Compared with the pristine H-?, the acid treated H-? showed lower activity which presented that the weak acid sites were not the active sites of this reaction.3 By alkaline treatment, mesoporous system had been introduced which shorten the diffusion length of reactants and products and eventually improved the catalytic activity.4 By alkaline-acid treatment, the as-prepared samples exhibited much larger SBET and VPore and lower acid contents. Those results revealed that appropriate acidity had a great influence on the catalytic activity in the presence of mesoporous system.5 In acid-alkaline modification experiment, by changing the sequence to acid-alkaline, mesoporous system was also introduced to H-?. The results showed that the acid properties were greatly influenced which was not good for the reaction.6. The catalytic activity of the catalyst will be decreased rapidly after repeated use.The deactivated catalyst can be regenerated by CH3OH or C2H5OH washing and then calcined.