Mechanism of the CN-bond breaking in the hydrodenitrogenation of methylcyclohexylamine over sulfided NiMo/γ-Al2O3

✍ Scribed by Fabio Rota; Roel Prins

• Book ID: 104421096
• Publisher: Elsevier Science
• Year: 2000
• Tongue: English
• Weight: 215 KB
• Volume: 162
• Category: Article
• ISSN: 1381-1169
• DOI: 10.1016/s1381-1169(00)00303-4

✦ Synopsis

The hydrodenitrogenation HDN of methylcyclohexylamine was studied over sulfided NiMorg-Al O . 2-Methyl-2 3 Ž . cyclohexylamine MCHA is an intermediate in the HDN of toluidine that can be detected in addition to the main products, Ž . Ž . Ž . methylcyclohexene MCHE and methylcyclohexane MCH , when a high quantity of cyclohexene CHE was added to o-toluidine during HDN. The selectivity of MCH in the HDN of MCHA was about 20% at zero conversion. The detection of Ž . 2-methylcyclohexanethiol MCHT in the HDN of MCHA explains why MCH is observed as a quasi primary product in the HDN of o-toluidine. MCH is formed via nucleophilic substitution of the amine group of MCHA, giving MCHT, followed by C S bond hydrogenolysis. A kinetic investigation at different H S partial pressures showed that H S increases the rate of 2 2 nucleophilic substitution, but leaves the rate of the b-Hofmann elimination of ammonia from MCHA unchanged.