Aqueous phase hydrogenolysis of renewable glycerol to 1, 2-propanediol over bimetallic highly stable and efficient Ni-Cu/Al2O3 catalyst

Abstract

The effect of Cu and Ni supported over mesoporous alumina catalyst was investigated for hydrogenolysis of glycerol in the aqueous phase to produce 1, 2-Propanediol (1, 2-PD). Nanocrystalline Cu and Ni supported catalysts were prepared by the hydrothermal method, and were characterized by XRD, SEM, TEM, BET, ICP-AES, TPR, and XPS. The effect of reaction parameters like temperature, pressure, and time were studied in detail. In this work, it was found that the Cu-nanoparticles are the critical factor for the selective production of 1, 2-PD. Mesoporous alumina support played an important role for the Cu and Ni oxide particles. The acid and metal function both played an important role in getting higher selectivity of 1, 2-PD. The reaction condition of 200 °C, 50 bar, and catalyst to feed ratio of 0.1 displayed the best performance using NiCuAl-1 (5%Ni, 62%Cu, and 33%Al) catalyst with glycerol conversion of 67.1% and 1, 2-PD selectivity of 90.1%. The catalyst was recycled five times for checking its catalytic behavior on the conversion and selectivity, and it was found that the catalyst did not change its activity during the recycle test, confirming the true heterogeneous nature of the catalyst.