High-purity hydrogen production from biogas by sorption-enhanced steam reforming over Ni-MgO-CaO bifunctional catalyst with paper fiber as template

Sorption -enhanced steam reforming (SESR) process is a promising technology aiming at the production of high purity hydrogen with CO2 capture. The key to the success of this process is the availability of high-performance bifunctional catalysts. Herein, we develop a hollow microtubular Ni-MgO-CaO bifunctional catalyst with paper fiber as template. Due to the strong hygroscopic properties of paper fibers, it provides a method for the rapid synthesis of catalysts with design components by adsorbing solution. The characterizations indicate that the impregnation time (1 min vs 24 h) has no effect on the structural properties of Ni-MgO-CaO bifunctional catalysts. MgO as an inert spacer can weaken the sintering of CaO to ensure a stable CO2 uptake. Moreover, the agglomeration of Ni particles is inhibited by the MgO coating on their surface. 5Ni-10MgO-CaO as the best performing catalyst displays high stability for the SESR of biogas (SESRB) reaction, during which 94.1 % purity of hydrogen with a 95.2 % conversion of CH4 is stably produced and only 37.1 % decrease of sorption -enhanced effect is observed in 50 SESRB-calcination cycles.