| Friedel-Crafts acylation is an important step for synthesizing aromatic ketones. This process conventionally has been carried out by using homogeneous catalysts Lewis acid(e.g. metal halides) or Broensted acid(e.g. H2SO4, HCl, HF), which leads to many problems concerning handling, safety, corrosion and waste disposal etc. Besides, hazardous acyl halides are often used as acylating agents. Moreover, most reaction process is carried out in stirred tank reactor, with low reaction efficiency and selectivity, high operating strength and much waste, which is adverse to environmental protection and consumption.In this work, based on the efficient and environmentally friendly HBEA zeolite as catalyst, and lower hazardous acetic anhydride as acylating agent, Friedel-Crafts acylation of aromatics(toluene) and heterocyclic compounds(furan, 2-methylfuran, thiophene, 2-methylthiophene, N-methylpyrrole) were investigated as follows:(1) The effects of reaction factors on the acylation of aromatics and heterocyclic compounds were investigated in an autoclave or magnetic stirred tank.(2) Continuous liquid phase acylation of toluene and furan were carried out in a fixed bed reactor. That will provide basis for large scale process.(3) Catalysts were recovered and extracted in a soxhlet with dichloromethane. The parent and deactivated HBEA zeolites were compared through the analysis of SEM, TGA, 13 C NMR MAS, 27 Al NMR MAS and Py-FTIR. It shows that the organic compounds(4-MAP and ‘coke‘) were adsorbed and retained in the zeolites. It is responsible for the deactivation of zeolites.(4) To delay the deactivation of zeolites, the effects of solvent and acid modification of zeolites were studied. It shows strong polar solvent can delay the deactivation. And the catalytic stability of zeolite was improved after the treatment with the hydrochloric and nitric acids.(5) The relationship between structure and activity of aromatic ring was studied preliminarily. |
