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[Display omitted] • Ni-based catalysts supported by mesoporous CeO 2 were successfully prepared for GDR. • Thermodynamic study of GDR was carried out to compare the experimental data. • 5Ni/CeO 2 presented the highest activity with glycerol conversion of 84.1% at 750℃. • Ni loading ratio of 5 could reduce the generation of filamentous carbon during GDR. In this paper, the mesoporous Ni/CeO 2 catalyst with high specific surface area was prepared by the colloidal solution combustion method and used for the production of syngas by glycerol dry reforming (GDR). The thermodynamic analysis was conducted by using a non-stoichiometric methodology based on the minimization of Gibbs's free energy. The characterization results show that the higher the Ni content, the weaker the interaction between Ni and the CeO 2 support. 5Ni/CeO 2 shows the most consistent Ni dispersion and uniform particle size, and it has the best catalytic activity in the GDR and the conversion of glycerol can reach 84.1 % at 750 °C. Besides, all catalysts exhibited excellent stability during the 10 h catalytic process. The temperature-programmed oxidation (TPO) results show that Ni loading ratio of 5 can reduce the production of filamentous carbon. Based on a kinetic model assuming a power law as a first-order reaction, the activation energy of the Ni-based catalyst for glycerol dry reforming was calculated. [ABSTRACT FROM AUTHOR]

For the fixed-bed reactor configuration in the sorption-enhanced steam reforming process (SERP), solid mixture of catalyst and sorbent is stationary and alternatively exposed to reaction and regeneration conditions for multi-cycles by periodically switching the feed gases for enhanced hydrogen production with in-situ CO 2 removal. A NiO/NiAl 2 O 4 catalyst was synthesized by the co-precipitation method with rising pH technique and the crystalline spinel phase of NiAl 2 O 4 was formed under the calcination temperature of 900 °C. The catalyst was characterized by X-ray powder diffraction (XRD), scanning electron microscope (SEM), thermo-gravimetric analysis (TGA), and N 2 adsorption–desorption. The non-stoichiometric thermodynamic calculation was carried out to determine the effects of temperature and in-situ CO 2 removal on the enhancement of hydrogen production by SERP from glycerol at 425–700 °C. The multi-cycles on reaction and regeneration for hydrogen production by SERP from glycerol were performed by NiO/NiAl 2 O 4 catalyst and CaO based sorbent in a fixed-bed reactor. The results showed that hydrogen production by SERP can be clearly divided into three periods, and the experimental gaseous products were compared with non-stoichiometric thermodynamic calculations. It is obvious that H 2 purity was greatly increased, and CO 2 , CO and CH 4 concentrations were reduced by in-situ CO 2 removal during the pre-breakthrough period. It is found that enhanced hydrogen production was mainly depended on in-situ CO 2 removal. The operation durations for producing high-purity hydrogen of more than 90% were decreased with the increase of the cycles. It may due to the decrease in the reactivity of CaO based sorbent after multi-cycles reaction and regeneration. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mesoporous Ni-Cu/CeO 2 was successfully synthesized to APR of biodiesel byproduct glycerol. • 1Ni2Cu/CeO 2 presented superior activity and multi-cycle stability in APR. • Cu element in catalysts effectively improved WGS and inhibited CH 4 formation. • Enhanced WGS and reduced methanation were achieved by in-situ CO 2 removal. Aqueous phase reforming (APR), regarded as one method for inexpensive H 2 production, was widely studied due to lower temperature and unnecessary to vaporize water and fuels. In this study, the mesoporous CeO 2 , regarded as a metal oxide carrier, was first prepared by colloidal solution combustion, and then the Ni-Cu bimetallic supported on mesoporous CeO 2 was successfully synthesized to investigate the catalytic performance in APR of biodiesel byproduct glycerol. The results show that the Cu element in the catalysts can effectively improve water–gas shift (WGS) reaction and inhibit the formation of methane, which increases the H 2 production rate from 125.08 to 195.57 µmol⋅min−1⋅g cat−1. The higher reaction temperature is beneficial to the H 2 production rate, but not to H 2 selectivity. Kinetics analysis indicates that catalyst of 1Ni2Cu/CeO 2 + 0.2gCaO has the lowest apparent activation energy (29.86 kJ⋅mol−1). CaO is introduced as an absorbent to improve WGS reaction and reduce methanation reactions through in-situ CO 2 removal and capture. The reaction path and mechanism of APR of glycerol are also discussed in this paper. [ABSTRACT FROM AUTHOR]