The production of renewable transportation fuel through fed-batch and continuous deoxygenation of vegetable oil derived fatty acids over Pd/C catalyst

Renewable fuels such as green diesel from renewable biomass have received attentions because of energy and environmental concerns. Deoxygenation, used to upgrade biomass derived oils has been applied intensively nowadays. To successfully improve this process, fed-batch and following continuous processes on real biomass derived fatty acids need to be investigated. In this study, liquid-phase deoxygenation of vegetable oil derived fatty acids was carried out over 5% Pd/C with cofeeding H2. With sufficient hydrogen, complete hydrogenation of unsaturated fatty acids occurred, leading to successive deoxygenation of the saturated fatty acids with n-alkane yields of 99% and 88% and average CO2 selectivity of 94.9% and 94.6% in the fed-batch and continuous mode, respectively. After hydrogenation is completed, lower than 5% of effective H2 partial pressure was found to be favorable for the decarboxylation pathway and ideal for deoxygenation of biomass derived fatty acids. Copyright © 2015 John Wiley & Sons, Ltd.