AlCl3 immobilized on silicic acid as efficient Lewis acid catalyst for highly selective preparation of dicyclohexylamine from the vapor phase hydroamination of cyclohexene with cyclohexylamine

Abstract

An efficient and stable Lewis acid catalyst silicic acid (SA)-immobilized AlCl3 (AlCl3-SA) has been successfully prepared by the chemical bonding method in this work. The results indicated that the immobilized 15%AlCl3-SA exhibited excellent catalytic performance and stability in the vapor phase hydroamination of cyclohexene with cyclohexylamine. 58.5% cyclohexene conversion with 98.7% selectivity to dicyclohexylamine was still maintained after running for over 150 h, and the space time yield of dicyclohexylamine was 142.6 mol/h·m3. The developed AlCl3-SA catalyst had the advantages of low cost and long-time stable activity. Maybe this work provides a promising approach for hydroamination of olefins to amines.