Simple fabrication of molecular sieving carbon for biogas upgrading via a temperature controlled carbonization of Phyllostachys pubescens

摘要

In this study, molecular sieving carbons (MSCs) for biogas upgrading were successfully fabricated by a simple temperature controlled carbonization of moso bamboo (Phyllostachys pubescens) without energy consuming steps (i.e. char activation and pore modification). As the carbonization temperature increased from 600 to 900 degrees C, the specific surface area of bamboo charcoals increased and the pore size distribution of bamboo charcoal became narrower and closer to the dimensions of CH4 (0.38 nm). Bamboo charcoals had a more disordered carbon stacking structure than commercial MSC and contained more surface oxides, which contribute to greater surface reactivity than commercial activated carbon. Bamboo charcoal carbonized at 900 degrees C had the highest CO2 adsorption capacity (121.6 g kg(-1)), even higher than commercial MSC (102.88 g kg(-1)). Despite the poor kinetic CO2 adsorption properties of bamboo charcoals compared to commercial MSC, synthetic biogas (60% CH4 + 40% CO2) was successfully upgraded to concentrated CH4 (>90%) by small-scale pressure swing adsorption using bamboo charcoal. It is expected that bamboo charcoals can contribute to sustainable small-scale biogas upgrading. (C) 2015 Elsevier Ltd. All rights reserved.