Catalyst and aromatic amino compound preparation method

Abstract

The present invention provides a catalyst and an aromatic amino compound preparation method. The catalyst comprises a carrier, a main precious metal, a minor precious metal, a main non-precious metal and a minor non-precious metal, wherein the main precious metal, the minor precious metal, the main non-precious metal and the minor non-precious metal are loaded on the carrier, the main precious metal is Pd, the minor precious metal is Pt, the main non-precious metal is Fe, Ce or Mn, and the minor non-precious metal is at least one selected from Ni, Cu, Zn, Co, Mo, V, Sn and a rare earth metal. According to the present invention, the catalyst has high catalysis activity and high selectivity when the catalyst is used for catalyzing aromatic nitro compound hydrogenation to produce aromatic amino compounds, and the by-product content can be significantly reduced so as to obtain the high aromatic amino compound yield.

Description

technical field [0001] The invention belongs to the technical field of catalytic hydrogenation, and in particular relates to a catalyst and a preparation method of an aromatic amino compound. Background technique [0002] The hydrogenation of aromatic nitro compounds to aromatic amino compounds is one of the main ways in the chemical industry to produce aromatic amino compounds, which are the main components in the production of fine chemicals, specialty chemicals and even bulk chemicals, such as aniline or toluene di amine. [0003] The prior art has disclosed a variety of catalysts for catalyzing the hydrogenation of aromatic nitro compounds to generate aromatic amino compounds. Generally, supported non-precious metal catalysts, Raney type catalysts or supported catalysts containing noble metals can be used, as disclosed in US Patent No. 2,823,235. The catalyst (Pd-Pt-Fe / C) of loading palladium, platinum and iron on carbon black, wherein palladium is as main noble metal c...

AI Technical Summary

Problems solved by technology

[0004] Chinese patent ZL02822082.X uses a powdered supported hydrogenation catalyst to catalyze the hydrogenation of nitrobenzene and dinitrotoluene to synthesize aromatic amino compounds, and its catalytic active components include a mixture of major noble metal components, secondary noble metal components and non-precious metal components , wherein, Pt as the main noble metal component, Pd, Ru or Rh as the secondary noble metal component, V, Fe, Mn, Ce or Cr as the non-noble metal component; or Pd as the main noble metal component, Ru or Rh as the secondary To noble metal component, V, Fe, Mn, Ce or Cr as non-noble metal component; or Pd as main noble metal component, Pt as secondary noble metal component, and Ce or Cr as non-noble metal component, the above active group Loaded on activated carbon, carbon black, alumina and silicon oxide to obtain a supported catalyst, when used to catalyze the hydrogenation of nitrobenzene to aniline, although the activity and selectivity are higher than other catalysts, the by-products in the obtained aniline The content of the product cyclohexanone is relatively high, and cyclohexanone needs to form a Schiff base with a higher boiling point with aniline under the action of a catalyst in the subsequent treatment to be removed, which is not only cumbersome to handle, but also leads to a decrease in the yield of aniline

Images