Catalyst and preparation method for preparing o-fluoroaniline by hydrogenation of o-fluoronitrobenzene

Abstract

The invention discloses a catalyst for preparing o-fluoroaniline from o-fluoronitrobenzene by hydrogenation. The catalyst contains an Al2O3 supporter and the following components in percentage by mass: 0.05%-1% of Pt supported on the Al2O3 supporter, 0.05%-3% of metal M1 and 0.01%-3% of metal M2, wherein the metal M1 is Pd, Sn or Zn; the metal M2 is K, Co, Ga, In, Mn, Ag or Ce. Besides, the invention also provides a preparation method of the catalyst. When the catalyst prepared by the preparation method is used for catalyzing o-fluoronitrobenzene hydrogenation, the mole conversion rate of o-fluoronitrobenzene is up to 100%, the mole percentage of a defluorination product is smaller than 0.1%, the amount of o-fluoronitrobenzene treated by the catalyst of unit mass is large, the use amount of the catalyst is small, and the catalyst can be reused after being regenerated.

Description

technical field [0001] The invention belongs to the technical field of catalyst preparation, and in particular relates to a catalyst and a preparation method for preparing o-fluoroaniline by hydrogenating o-fluoronitrobenzene. Background technique [0002] O-fluoroaniline is an important intermediate in the synthesis of fluorine-containing medicines and dyes. O-fluoroaniline can be used to synthesize thermosensitive dye FH-102, which is a kind of thermosensitive dye with wide application and excellent performance in black. The dye can be used in the production of computer terminal output printing paper, electrocardiogram recording paper, telephone fax paper and transparent heat-sensitive film for oil fields. At present, in China, o-fluoroaniline is mainly produced by reducing o-fluoroaniline with iron powder. This process will produce a large amount of iron sludge (every 1 ton of o-fluoroaniline will produce 2.2t~2.4t of iron sludge), and at the same time A large amount of...

AI Technical Summary

Problems solved by technology

This method requires less initial investment and is easy to implement, but it requires a lot of manpower, has poor safety, and produces a lot of waste liquid and waste residue. It has not yet been industrialized.

At present, there are few literature reports on the method and catalyst for the preparation of o-fluoroaniline by continuous fixed-bed catalytic hydrogenation. This process is safe, environmentally friendly, high in production efficiency, and requires less personnel. It is beneficial to large-scale industrial production in the long run.