(254t) Optimization of Sorption-Enhanced Glycerol Steam Reforming Reaction Process for High-Purity Hydrogen Production

As global demand for environmental-friendly energy has been increasing, many studies on biodiesel were conducted. With rapid growth of biodiesel market, a large amount of glycerol which is a byproduct in biodiesel production is inevitably flowed into the global market, and now became a serious surplus problem. Conversion of glycerol to hydrogen is one of attractive ways to use an excess amount of glycerol since hydrogen is a clean energy carrier that does not produce any pollutants during energy generation. Generally, conventional conversion of glycerol to hydrogen has been conducted through catalytic glycerol steam reforming (GSR) reaction. Previous studies, however, revealed that the conversion of glycerol to hydrogen is thermodynamically limited and the purity of produced hydrogen is low, so that additional purification steps are required for direct application. Note that the thermodynamic limitation can be overcome by a new concept, sorption-enhanced reaction process, which combines reaction and separation in a single reactor. In the sorption-enhanced glycerol steam reforming (SE-GSR) reaction process, byproduct CO₂ is removed by solid adsorbent, simultaneously with GSR reaction. In this manner, glycerol conversion can be dramatically increased by Le Chatelierâ??s principle, leading to the direct production of high-purity hydrogen. In this study, numerical simulation was carried out to elucidate the effects of various operating parameters on reaction performance and to optimize the SE-GSR reaction process. The results showed that high-purity hydrogen (>99.99%) production with good hydrogen selectivity (>99.99%) is achievable through the SE-GSR reaction process at high temperature, low pressure and high steam content.