Enhanced H2 production through biomass pyrolysis by applying alkaline ceramic lithium cuprate (Li2CuO2) as a bifunctional material

Abstract

Biomass has become an important research topic within different environmental and energy fields. In the present work, glucose (selected as a model) pyrolysis was examined in the presence of lithium cuprate (Li₂CuO₂) acting as a catalyst and a sorbent. The whole experimental analysis was performed using thermogravimetry, gas chromatography coupled with a catalytic reactor, and gas-phase FTIR spectroscopy. Moreover, solid products were analyzed via X-ray diffraction and FTIR spectroscopy. The results indicate that Li₂CuO₂ can be used as a bifunctional material, where H₂ production and carbon oxides (CO and CO₂) chemisorption are importantly enhanced during the whole glucose pyrolysis process. In fact, the highest H₂ production (196.7 mL g_glucose⁻¹) was obtained with a Li₂CuO₂ : glucose molar ratio of 1 : 5 at 700 °C. In addition, cycling experiments showed that this process can be performed several times with or without an oxidative regeneration step. A comparative analysis performed by adding CuO instead of Li₂CuO₂ confirmed the importance of the presence of lithium as a carbon oxide sorbent and even in promoting catalysis.