Thermo-Catalytic Reforming of spent coffee grounds

Abstract Conversion of spent coffee grounds through the Thermo-Catalytic Reforming system (TCR®) is evaluated in this study. While, the TCR® is a technology that has been developed by Fraunhofer UMSICHT, which combines an intermediate pyrolysis and a catalytic reforming. The temperature of the catalytic reformer is varied between 500 and 700 °C to achieve an optimum yield quantities and qualities of the products. The hydrogen concentration is maximized at a reforming temperature of 700 °C, and a gas yield up to 52 wt% is achieved. The thermal stable bio-oil produced at 700 °C has the highest calorific value of 36.8 MJ/kg with significantly low oxygen and water content, low viscosity and low TAN (total acid number). Furthermore, the maximum bio-oil and char yields are obtained at the lowest reforming temperature of 500 °C. Overall spent coffee grounds show a great potential as feedstock in the Thermo-Catalytic Reforming for energy and bio-chemicals production.