The cyclic operation of the Sorption Enhanced Reaction Process (SERP) for direct production of a hydrogen enriched stream by reaction of steam and methane is demonstrated using a pilot-scale unit. An admixture of a proprietary steam methane reforming catalyst and a propriety chemisorbent for carbon dioxide is used as packing in the reactor. Steady-state performance data are reported for a reaction temperature of 490°C, reaction pressures of 26 and 66 psia (179 and 455 kPa), and a feed reactant composition of 6:1 steam/methane. The process is capable of directly producing 88-95% H2 with methane as the primary impurity. The concentrations of CO2 and CO in the product hydrogen can be kept below 40 ppm by controlling the operating conditions of the process. The conversion of methane to hydrogen can be much larger than that dictated by thermodynamics in a catalyst-alone reactor. The hydrogen product purity, which increases with decreasing hydrogen productivity, can also be manipulated by changing the operating conditions of the process. These characteristics of the SERP may be attractive for direct production of essentially CO free hydrogen in a fuel cell application.
