Catalytic performance of Ni/CaO-Ca5Al6O14 bifunctional catalyst extrudate in sorption-enhanced steam methane reforming

Abstract

In this work, mm-sized shaped Ni/CaO-Ca5Al6O14 bifunctional catalyst extrudates were prepared by extruding sol–gel-derived Ni/CaO-Ca5Al6O14 powder, and applied to the sorption-enhanced steam methane reforming (SESMR) process. The Ca5Al6O14-stabilized bifunctional catalysts exhibited higher stability and CaO utilization efficiency than that of Ni/CaO when subjected to 50 carbonation–calcination cycles for CO2 capture, indicating the positive effect of Ca5Al6O14 incorporation. The Ni/CaO-Ca5Al6O14 extrudates possessed good activity and stability over 10 SESMR cycles, and showed advantages over the use of catalyst and sorbent mixture, including an extended prebreakthrough time and a higher catalytic activity. In particular, the Ni/CaO-Ca5Al6O14 extrudate consisting of 15wt% (mass fraction) Ni, 61.7wt% CaO and 23.3wt% Ca5Al6O14 provided high activity and stability for the SESMR process, even at a low H2O/CH4 molar ratio of 2 over 20 SESMR cycles. These results clearly demonstrate that the Ni/CaO-Ca5Al6O14 extrudate is an interesting candidate for the SESMR process.