Hydrogen production from pruning waste biomass by integration of hydrothermal treatment and aqueous phase reforming

Abstract

This research investigates hydrogen production from urban pruning waste biomass through combined hydrothermal treatment and aqueous phase reforming. Optimization of treatment parameters (temperature, time and pH) yielded a hydrolysate rich in water-soluble compounds. The most effective conditions were found at 180 °C and 60 min, achieving a balanced hydrolysis and solubilization of lignocellulosic waste. Low pH, induced by organic acids from the waste, drove hydrotreatment, but further acid addition hindered solubilization. Aqueous phase reforming at 220 °C with a carbon-supported Pt catalyst resulted in enhanced carbon conversion and H2 production at an initial carbon concentration of 1,000 mg/L. Increasing Pt load from 3 to 5 % wt. improved production and selectivity, plateauing at 7.5 % wt. Optimal conditions demonstrated a H2 production of 17 mmol per gram of dissolved organic carbon, affirming the viability of this scheme for pruning waste valorization.