Direct production of isomerized biodiesel over MoS2/ZrPOx under solvent-free conditions

Abstract

The catalytic deoxygenation and isomerization of biolipids in one pot is a challenge in the production of high-quality biodiesel. Herein, series of bifunctional catalysts, combining with in-situ sulfided MoO3 and phosphoric acid modified-ZrO2, were fabricated for upgrading of biolipid under solvent-free conditions. It is demonstrated that the bifunctional catalysts exhibit great performance for the hydrotreating of methyl palmitate and raw biolipid, affording up to 90% of total hydrocarbons with 20.3% and 18.7% of isomerized alkanes in diesel range. Among several studied ratios, the catalyst with Mo loading of 12.5% and P/Zr ratio of 1/7 achieves the highest yield of i-alkanes due to a coeffect of MoS2 and acid sites on the surface based on characterizations. The regenerated catalyst also shows excellent performance with no significant change in the structure. Moreover, a synergy between MoS2 and phosphoric acid is discussed to elucidate the high activity of biolipid conversion.