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In this work, two different types of catalysts with MgO support for aqueous phase reforming of glycerol were prepared by the sol-gel method and calcining method, respectively, and the active metals (nickel or/and cobalt) were added by the initial wet impregnation (IWI) method. It is found that the catalyst supported by gelatinous MgO presents better dispersion and the amount of hydrogen produced by the catalyst containing gelatinous MgO support is more than 1.5 times compared with other catalysts. For the Ni–Co bimetallic catalysts, the higher reaction temperature is beneficial to hydrogen yield, but decreases hydrogen selectivity. A high concentration of glycerol increases hydrogen yield and selectivity. Introducing CaO as an absorbent in aqueous phase reforming can improve WGS reaction and reduce methanation reaction through in-situ CO 2 removal and capture. The gelatinous Ni–Co/MgO catalyst presents superior activity and multi-cycle stability. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: A detailed comparative study on thermodynamic and experimental analyses of glycerol reforming for hydrogen production has been conducted in terms of the effects of temperature, pressure, water to glycerol feed ratio, feeding reactants to inert gas ratio and feeding gas flow rate (residence time). The thermodynamic analysis was conducted by using a non-stoichiometric methodology based on the minimisation of Gibbs free energy. And the experiments were carried out with a pilot scale set-up. The results show that the thermodynamic and experimental data agree fairly well with each other. The measured hydrogen production is slightly lower than that predicted by the thermodynamic analysis, which is mainly because the conversion of steam is incomplete. High temperature, low pressure, low feeding reactants to inert gas ratio and low gas flow rate are favourable for steam reforming of glycerol for hydrogen production. There is an optimal water to glycerol feed ratio for steam reforming of glycerol for hydrogen production which is about 9.0. The glycerol conversion is a strong function of water to glycerol ratio, whereas a weak function of other parameters over the conditions of this work. A novel adsorption enhanced reaction process incorporating water and heat recovery is proposed for further optimisation of hydrogen production from steam reforming of glycerol. [ABSTRACT FROM AUTHOR]