COMPARISON OF SULFIDIC AND NON-SULFIDIC CATALYSTS FOR HYDROTREATING OF RAPESEED OIL

The activity of commercial sulfidic Ni-Mo and Co-Mo and reduced Ni catalysts supported on alumina for hydrotreating of rapeseed oil were compared. Continuous flow reactor with inner diameter 21 mm and fixed bed of catalyst was used. The reaction temperatures in range 260 - 360 degrees C, the pressure of 4 MPa and WHSV of 2 h(-1) were tested. The composition of liquid and gaseous products was determined by GC-FID and GC-FID/TCD, respectively. Complete deoxygenation of triglycerides was achieved at temperatures of 320 degrees C with Ni-Mo and Ni catalysts and 340 degrees C with Co-Mo catalyst. Massive cracking accompanied by loss of activity at higher reaction temperatures was observed on Ni catalyst. Gaseous products from Ni catalyst contained only the minor amount of CO, CO2 and propane in contrast to sulfidic catalysts. It was caused by methanation of CO and CO2 and hydrogenolysis of propane. Hydrodecarbonylation (HDCn) and hydrodecarboxylation (HDCx) reactions were dominant pathways for oxygen removal in case of Ni catalyst in contrast to sulfidic types. Introduction The increasing worldwide consumption of fossil fuels evokes efforts of usage of renewable raw materials for the production of biofuels which decreases the accumulation of greenhouse