Hydrodeoxygenation of vanillin using palladium on mesoporous KIT-6 in vapour phase reactor

Mesoporous KIT-6 was synthesised by using hydrothermal method. Different weight percentage of 1, 3, 5 and 7 wt.% of palladium (Pd) was impregnated on KIT-6 by wet impregnation method. All the palladium catalyst was characterized by XRD, ICP-OES, BET, TPR, XPS, FT-IR, DRS-UV and TGA techniques. The morphology of the catalyst was identified by FESEM with EDS and HRTEM analysis. A typical lignin derived model compound (vanillin) was tested for hydrodeoxygenation (HDO) reaction using Pd/KIT-6 catalyst in fixed bed reactor. The activity of the catalyst was evaluated for HDO of vanillin by optimizing temperature (100-300 degrees C) and weight percentage of Pd loading onto KIT-6 (1, 3, 5 and 7 wt.%). The conversion of vanillin, selectivity of vanillyl alcohol and p-cresol were confirmed by gas chromatography. The investigation of the study showed that 5 wt.% of Pd/KIT-6 catalyst showed 98% conversion of vanillin and 94% selectivity of p-cresol at 300 degrees C for 6 h. The time studies were also conducted for all the catalyst in the temperature range of 100 to 300 degrees C revealed that Pd/KIT-6 had higher conversion and maximum selectivity at 6 h. The activity of Pd loaded catalyst was comparatively better up to 3 cycles. Selectivity of the vanillyl alcohol was preferably observed by Pd loading (1 wt.%) at short time (1 h) whereas p-cresol selectivity was observed at long time (6 h). (C) 2017 Elsevier B.V. All rights reserved.