Development of Advanced Reforming System for H2 Station Using CO Converter Equipped with CO2 Selective Membrane II

Abstract

We developed a novel membrane reactor consisted of a CO shift catalyst and a membrane for selective CO2 separation. First, we successfully developed novel facilitated transport membranes with excellent performances exceeding our target values, i.e. CO2 permeance of 1x10-4 mol/(m2skPa) and CO2/H2 selectivity of 100 at 160 oC. The developed membrane maintained high performances for more than 400 hours. Second, we developed CO shift catalysts, which had high activity for the CO shift reaction at 160 oC. Among the catalysts developed in this study, precious metal-based catalysts had quite high activities. By combining the developed membrane and catalyst, a membrane reactor-type CO converter was fabricated. By using the CO converter, CO and CO2 concentrations in feed gas (14.8 and 7.4 %, respectively) were drastically reduced. Observed CO and CO2 concentrations at the feed-side exit of the CO converter were 5 ppm and 0.3 %, respectively.