International Journal of Hydrogen Energy, Vol.38, No.14, 6072-6078, 2013
Sorption enhanced hydrogen production using one-body CaO-Ca12Al14O33-Ni composite as catalytic absorbent
Catalytic absorbents containing CaO and Ca12Al24O33 and metallic Ni in one body were prepared in combination of precipitation and hydration and tested for sorption enhanced hydrogen production (SEHP). Adding aluminum precursor in the precipitation step induced the formation of Ca22Al14O33 and FIB-TEM analysis revealed that Ca12Al14O33 provides spacious pathway for CO2 diffusion by forming porous structure. In thermogravimetric analysis, Ca22Al14O33 was identified as an excellent support material providing superior cyclic stability for Ca-based sorbent. Catalytic absorbents were prepared with adding various amount of Ni precursor (3, 5, 7, and 10 wt %). The SEHP test with the catalytic absorbents showed that 7wt% of Ni loading resulted in excellent performance in terms of H-2 production and CH4 conversion. Ni agglomeration was observed when 10 wt% of Ni is loaded on the catalytic absorbent. Copyright (C) 2012, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.
Keywords:CO2 capture;Sorption-enhanced hydrogen production;CaO absorbent;Catalytic absorbent;Reforming;Calcium aluminate