New Hybrid Materials for Improved Hydrogen Production by the Sorption-Enhanced Steam Reforming of Butanol

Catalytically assisted steam reforming coupled with the selective separation of the produced CO2 is a promising approach for improved H-2 production. In this work, we synthesized a new mixture (K-Ni-CaO/HTlc) of two potential sorbents CaO and hydrotalcite (HTlc), the promoter K, and the reforming catalyst Ni. This hybrid material was tested for the sorption-enhanced steam reforming of butanol (SESRB) and its performance was compared to that of two unpromoted hybrid materials Ni-CaO/HTlc and Ni-CaO/Al2O3. All these hybrid materials were able to produce high-purity H-2. In particular, K-Ni-CaO/HTlc exhibited the highest H-2 concentration (98.7 mol%) and adsorption capacity (12.8 mol CO(2)kg(sorbent)(-1)) at 823 K. The cyclic durability was tested for 25 cycles, and K-Ni-CaO/HTlc was stable for up to 21 cycles. Conversely, Ni-CaO/HTlc and Ni-CaO/Al2O3 remained stable for 15 and 11 cycles only. The addition of K as a promoter was justified by the improved H-2 production and multicycle resilience. Finally, a plausible reaction mechanism for SESRB that predominates over the investigated hybrid materials was suggested.