Photocatalytic reforming of pinewood (Pinus ponderosa) acid hydrolysate for hydrogen generation

Dilute acid hydrolysis of milled Pinus ponderosa (pinewood) was performed in a high temperature high-pressure 300 ml SS316 Parr reactor to produce sacrificial electron donors for downstream photocatalytic H-2 generation. Samples of the hydrolysate withdrawn at regular time intervals were analysed for total organic carbon (TOC), sugars and organic compounds. The influence of acid type (HCl, H2SO4, and HNO3) and its concentration, temperature, residence time and biomass loading on pinewood hydrolysis and release of the glucose and xylose sugars (GX) was investigated. Maximum GX sugar yield was obtained with 1 v/v% HC1 hydrolysis of 6.66 wt% pinewood slurry at 180 degrees C for 120 min. The hydrolysate was treated with activated charcoal (AC) and photoreformed for H-2 generation using 1% Pt/TiO2 catalyst. Under optimized reaction conditions, 8 consecutive photo catalytic cycles of the hydrolysate produced cumulative yield of 19.9 ml H-2/g pinewood, which is 26 mol% of GX observed in the hydrolysate. (C) 2016 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.