Liquid Phase Selective Hydrogenation of Citral over Bimetallic Transition Metal Catalysts

Abstract

Silica supported bimetallic catalysts of Co-Ni, Ni-Cu and Cu-Co were prepared by deposition precipitation method, calcined at two different temperatures 475°C and 675°C. The prepared catalysts were characterized by BET surface area, SEM, EDX, FT-IR, thermogravimetry and XRD techniques. The XRD measurement of Ni–Cu/SiO₂ catalyst has peaks due to CuO and NiO oxides. The catalytic activity and selectivity of these prepared catalysts towards liquid phase selective hydrogenation were studied. Amongst the studied catalysts, Co–Ni/SiO₂ cacined at 475°C had presented higher selectivity in terms of citral towards unsaturated alcohols (geraniol and nerol) in a isopropanol solvent medium and 0.2% catalyst loading, at 90°C temperatures under 4 bar pressure with 750 rpm agitation.