Experimental study of the application of a NiO/NiAl2O4 catalyst and a CaO-based synthetic sorbent on the Sorption Enhanced Reforming process

Abstract

A CaO-based synthetic sorbent and a NiO/NiAl2O4 catalyst are synthesized and tested under Sorption Enhanced Reforming (SER) conditions in a fixed bed reactor. The effect of temperature, steam-to-methane ratio (S/C) and sorbent-to-catalyst proportion (Z) are studied. A SER based plant simulation model is implemented to evaluate if the operating conditions chosen allow for a self-sustained plant from a thermal energy consumption standpoint.The most appropriate temperature for SER test is 650 °C. At 600 °C the catalyst seems to be not sufficiently active, while at 700 °C, a longer breakthrough period results. SER equilibrium is reached even at the lowest S/C ratio of 1.6, obtaining H2 purity of 82 vol.% (dry basis). For the SER based plant simulation developed, the low S/C ratio of 1.6 allows a self-sustained plant where the energy required in the calciner for CaCO3 decomposition is supplied by burning the off-gas from the H2 purification unit.