Activity and Selectivity of Nanostructured Sulfur-Doped Pd/SBA-15 Catalyst for Vegetable Oil Hardening

Abstract

Sunflower and canola oils were hardened over a novel sulfur-promoted Pd catalyst. The formulated catalyst comprised of 0.7 wt % palladium nanoparticles promoted with 0.3 wt % sulfur highly dispersed on mesoporous silica SBA-15 (0.7% Pd−0.3% S/SBA-15). The effect of temperature (80−130 °C) and H2 pressure (3.6−9.3 atm) on the activity, selectivity, and trans (TFA) and saturated (SFA) fatty acids formation were studied for both oils. Under similar temperature and H2-pressure conditions, sunflower and canola oils exhibited different reactivities toward hydrogenation. For both oils, the activity of the catalyst increased with the temperature and with the pressure. However, increasing the temperature raised the levels of trans C18:1 especially at low hydrogen pressure. Partial hydrogenation of both oils from initial iodine (IVo) values of 120−130 to a final value of 90 with the sulfur-doped Pd catalyst yielded modified oils with a low TFA level (6%) and also controlled the formation of SFA (∼7%) under mild tem...