Catalyst for o-fluoro nitrobenzene hydrogenation and its preparation and application

Abstract

The invention concerns the reaction of benzene catalyst adding hydrogen, specific speaking, it's a kind of catalyst to produce 4-ammonia base-3-F benzene fen and its application. The catalyst is madeof carrier, active parts and helping dose. The main active parts are: dear metal Pt, Pd or Rh, whose weight is of catalyst 0.1%--20%. Help doses are IA, IIA, IIIB, VIII or Sparse soil chemical element.The catalyst has the feature of high active in reactivation, good choosing ability and many reuses. The catalyst can also be used in other replacing nitric unit benzene adding hydrogen and catalystpr ocess.

Description

technical field [0001] The invention relates to heterogeneous catalytic hydrogenation reaction of nitrobenzene, in particular to a catalyst for hydrogenation of ortho-fluoronitrobenzene to produce 4-amino-3-fluorophenol and its preparation and application. Background technique [0002] 4-Amino-3-fluorophenol is an intermediate in the production of benzoylurea, a flufenoxuron-type insecticide, and can be used in the production of phenoxyacetate herbicides as well as 3 , 4,5,6-Tetrahydrobenzopyrrolone-type herbicides and hair dyes and bactericidally active compounds. The traditional synthetic method of 4-amino-3-fluorophenol is to carry out azolation reaction with m-fluorophenol after diazotization of p-aminobenzenesulfonic acid, and then introduce 4-(2-fluoro-4-hydroxyl phenylazo)benzenesulfonic acid, which is reduced in sodium bisulfite to obtain the target product (J.Chem.Soc.1964, p.473). [0003] There have been many patent reports on the production of p-aminophenol thr...

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Problems solved by technology

[0005] Improvement of activated carbon, silica and alumina-supported noble metal catalysts for catalytic hydrogenation of o-fluoronitrobenzene to 4-amino-3-fluorophenol by patent search Report on the catalytic performance of the corresponding substituted p-aminophenol or p-aminophenol by hydrogenation with other substituted nitrobenzene or nitrobenzene