Anilines From Phenols

Applied Catalysis A: General 180 (1999) L1±L3

Letter

High catalytic activity for synthesis of aniline from phenol and
ammonia found on gallium-containing MFI
Naonobu Katada*, Shuji Kuroda,Miki Niwa
Department of Materials Science, Faculty of Engineering, Tottori University, 4-101, Koyama-cho Minami, Tottori 680-8552, Japan
Received 2 September 1998; received in revised form 22September 1998; accepted 2 October 1998

Abstract
Gallium-containing zeolitic materials, i.e., MFI-type gallosilicate and gallium-loaded ZSM-5 zeolite, exhibited quite high
activity for vapor-phasereaction of phenol and ammonia into aniline. Co-presence of the extra-framework gallium species and
the ion-exchange site ascribed to framework gallium or aluminum atom is considered to generate the highactivity. # 1999
Elsevier Science B.V. All rights reserved.
Keywords: Aniline; Phenol; Ammonia; Gallosilicate; Gallium-loaded ZSM-5; Extra-framework gallium; Solid±acid catalysis

1. IntroductionAniline is an important intermediate for pharmaceutical and chemical industries, and has been conventionally produced by reduction of nitrobenzene. In
order to suppress the cost for raw material,reductiveamination of phenol on precious metal catalyst [1] and
direct amination on solid±acid catalysts such as silica±
alumina [2], titania±zirconia [3] and alumina [4] have
been investigated. Inthe last decade, the latter reaction
using a series of modi®ed aluminas has been applied to
practical use [5,6]. For this reaction, enhancement of
activity of catalyst is still being attempted tocarry out
the reaction at low temperature under low pressure of
ammonia to suppress the catalyst deactivation and
cost for utility. Fundamental studies showed that a
*Corresponding author. Tel.:+81-857-31-5684; fax: +81-85731-0881; e-mail: katada@chem.torrori-u.ac.jp

relatively weak acid such as titania±silica was active
for this reaction [7]; zeolites, whose acid property
could be...