Biomass waste as a raw material for the mesoporous catalyst synthesis and its application in HDO of guaiacol for biofuel production

Abstract

Platinum-modified activated carbon was synthesized and studied for hydrodeoxygenation (HDO) of guaiacol. The activated carbon support was prepared using orange peel from industrial waste. Platinum was added by wetness impregnation. The activity was compared with that of platinum supported on mesoporous silica and commercial activated carbon catalysts. The catalysts prepared were characterized by different techniques: XRD and N2 adsorption isotherms to confirm the mesoporous structure, and XPS, H2-Chemisorption and Boehm titration to determine active sites and acidity. The results showed that high-surface-area active carbon support favors the formation of small platinum metallic particles, highly dispersed over the surface. The catalysts were active for guaiacol HDO performed in the laboratory at 200 °C and 12 atm of H2 in a Batch PARR reactor. Carbon was activated using phosphoric acid during the synthesis. The interaction between the peculiar acidity generated on the support by H3PO4, accompanied by the high hydrogenation capacity of the metallic platinum particles, enhanced catalytic activity, and selectivity for deoxygenated products. The most acidic-activated carbon support modified with 0.5 wt% of platinum was the most active catalyst in the HDO of guaiacol, reaching 88 mol% of guaiacol conversion and selectivity of 78% toward HDO products such as phenol, benzene and cyclohexane. The novelty of this research aims at developing an environmentally friendly catalyst to produce biomolecules of high aggregated value at mild reaction conditions reducing energy consumption.