M. Lequitte, F. Figuéras, C. Moreau
May 19, 1992
Citations
0
Influential Citations
7
Citations
Journal
Applied Catalysis A-general
Abstract
Abstract The conversion of sec-butylamine (BA ) has been investigated over MFI, MOR, FAU, BEA and MAZ zeolites. Faujasites were used in the H and Ce forms. The products of the reaction are 1- and 2-butenes, and di-sec-butylamines (di-sec-BA). Butene formation follows a zero order relative to the pressure of butylamine, while dibutylamine formation follows a first order. The catalytic activity for deamination to butenes is related to the total number of acid sites. An effect of the zeolite structure is observed: at similar aluminium content, MFI and MOR appear more active than FAU and BEA for butene formation. The formation of dibutylamines is observed on large pore zeolites only, and results from two different pathways, di-sec-butylamine appearing as a secondary product in the presence of non-dealuminated H-form of Y zeolites, and as a primary product in the presence of Ce 3+ exchanged and dealuminated Y zeolites. This change is interpreted in terms of a classical consecutive reaction scheme in the former case, through addition of sec-butylamine to butene intermediates catalyzed by Bronsted acids, and in terms of a parallel reaction scheme in the latter case, through condensation of two sec-butylamine molecules catalyzed by Lewis acids.