METHOD FOR PREPARING ANILINE AND/OR N-METHYLANILINE AND CATALYST FOR ITS Russian patent published in 2005 - IPC

FIELD: organic chemistry, chemical technology.

SUBSTANCE: invention relates to the improved method for preparing aniline and N-methylaniline. Method involves gas-phase catalytic reduction of nitrobenzene with methanol or formaldehyde aqueous solutions in preparing aniline and N-methylaniline and formaldehyde aqueous solutions in preparing aniline. Preferably, in preparing aniline and N-methylaniline method involves reduction with methanol an aqueous solution in the concentration 60-80 wt.-% in the molar ratio nitrobenzene to methanol = 1:(1.1-3.5). In preparing aniline method involves preferable reduction with formaldehyde aqueous solution in the mole ratio nitrobenzene to formaldehyde = 1:(1.5-4.0) and temperature 220-250°C. Also, invention relates to applying catalyst in preparing aniline and N-methylaniline comprising zinc, copper and chrome oxides on aluminum oxide and promoting with metal oxides from group comprising iron, manganese, bismuth, cobalt and molybdenum. The content of zinc is 0.1-10% of the catalyst mass, the total content of cooper and chrome is 0.05-15% to zinc mass, and the total content of other metals is 1.0-3.0% to the mass of zinc-copper-chrome components. Proposed method provides carrying out the process without feeding molecular hydrogen to the system with conversion of nitrobenzene up to 100% and the preferable preparing aniline and N-methylaniline depending on parameters of the process. On its base the effective manufacturing aniline and N-methylaniline can be organized using free powers of gas-phase catalytic manufactures.

EFFECT: improved preparing method.

5 cl, 1 tbl, 7 ex