Catalytic activity of zeolites for synthesis reaction of methylenedianiline from aniline and formaldehyde

The catalytic activities of Y-, beta-, and ZSM-5-zeolites for methylenedianiline (MDA) synthesis from the condensation reaction of aniline and formaldehyde have been investigated. Among beta-zeolites with various Al concentrations (Si/Al ratios from 10 to 120 mol mol(-1)), beta-zeolite with Si/Al ratio of 13.6 mol mol(-1) shows the best catalytic performance in MDA synthesis. Y-zeolite exhibited lower catalytic activity than beta-zeolites under the identical reaction conditions, however, exhibited the higher selectivity to 4,4'-MDA. Furthermore, it revealed that aniline/formaldehyde and catalyst/formaldehyde ratio, and reaction temperature also influenced on the MDA yield and isomers distribution. (c) 2005 Elsevier B.V. All rights reserved.