Tandem bed configuration for sorption-enhanced steam reforming of methane

The required properties of a CO2 sorbent for sorption-enhanced steam–methane reforming (SESMR) are derived following a top-down approach. First the required CO2 equilibrium pressure of the sorbent is derived from system restraints, then a suitable sorbent is searched for matching the required CO2 pressure. The selected material, barium orthotitanate Ba2TiO4, has been characterized and tested on lab-scale. From this follows that the capacity and kinetics are poor compared with CaO, which has been investigated for SESMR. The best use of Ba2TiO4 is in combination with CaO, making use of the good properties of both: the high capacity and good kinetics of CaO, and the low CO2 equilibrium pressure of Ba2TiO4 allowing high CH4 conversion at relatively low steam-to-methane ratios (3–4).