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The Ni-based multifunctional catalysts for the sorption-enhanced steam reforming process (SERP) with simultaneous in-situ CO 2 removal were synthesized by the co-precipitation method with rising pH technique, and the crystalline spinel phases of NiAl 2 O 4 and MgAl 2 O 4 in the catalysts were formed under the calcination temperature of 900 °C. The catalysts were characterized by X-ray powder diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), thermo-gravimetric analysis (TGA), and N 2 adsorption-desorption. Nonisothermal and isothermal CO 2 sorption experiments were carried out to evaluate the activity of catalysts for CO 2 removal. Desorption and optimum sorption temperatures for CO 2 removal were determined. Hydrogen production from SERP of glycerol over the multifunctional catalysts has been experimentally evaluated under 550 °C and steam to carbon (S/C) ratio of 3. The multifunctional catalyst with the composition of 41.21 wt% NiO, 28.02 wt% Al 2 O 3 and 30.77 wt% CaO presented satisfactory hydrogen purity in the multi-cycles of reforming and regeneration processes. Enhanced hydrogen production was mainly depended on in-situ CO 2 removal, and the operation durations for producing high purity hydrogen in the initial 30 min were relatively stable. The multifunctional catalyst possesses uniform distribution of Ni, Ca and Al, contributing significantly to the excellent CO 2 sorbent capacity and reforming activity. This multifunctional catalyst synthesized offers a new scheme other than the conventional mixture of sorbent and catalyst for SERP. [ABSTRACT FROM AUTHOR]

In this study, the continuous sorption-enhanced steam reforming of glycerol to high-purity hydrogen production by a simultaneous flow concept of catalyst and sorbent for reaction and regeneration using two moving-bed reactors has been evaluated experimentally. A Ni-based catalyst (NiO/NiAl2O4) and a lime sorbent (CaO) were used for glycerol steam reforming with and without in-situ CO2 removal at 500 °C and 600 °C. The simultaneous regeneration of catalyst and sorbent was carried out with the mixture gas of N2 and steam at 900 °C. The product gases were measured by a GC gas analyzer. It is obvious that the amounts of CO2, CO and CH4 were reduced in the sorption-enhanced steam reforming of glycerol, and the H2 concentration is greatly increased in the pre-CO2 breakthrough periods within 10 min both 500 °C and 600 °C. The extended time of operation for high-purity hydrogen production and CO2 capture was obtained by the continuous sorption-enhanced steam reforming of glycerol. High-purity H2 products of 93.9% and 96.1% were produced at 500 °C and 600 °C and very small amounts of CO2, CH4 and CO were formed. The decay in activity during the continuous reaction-regeneration of catalyst and sorbent was not observed. [ABSTRACT FROM AUTHOR]