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Highlights: [•] Ni–Cu–Al catalyst for hydrogen production was synthesized by rising pH technique. [•] Experimental data were analyzed with non-stoichiometric thermodynamic calculation. [•] Catalyst deactivation due to carbon deposits in glycerol steam reforming was found. [•] Carbon removal was analyzed by TGA experiment during medium temperature oxidation. [•] Reforming was tested by separability kinetics of rate law and catalyst deactivation. [Copyright &y& Elsevier]

Abstract: The wet Flue Gas Desulfurization in the coal-fired power plants has been the most widely used because of its high SO2 removal efficiency, reliable and low utility consumption. The difficulty in the prediction of the SO2 removal from flue gas is that the performance of the system is related to a wide range of variables. In this paper, the SO2 was removed by absorbing and reacting SO2 with limestone slurry, and limestone scrubbing was accomplished in a spraying reactor. Experimental investigations for effects of different operating variables on the SO2 removal showed the reasonable process parameters such as the pH value of the liquid phase, droplet size of the spray and the flow rates of liquid and gas. The removal process was analyzed using the two-film theory of mass-transfer. Both the liquid and gas side resistances were important, and the absorption rate was controlled by a combination of both gas-film and liquid-film diffusion controls. A model of external mass-transfer with the effects of a chemical enhancement factor and sulfite concentration in the liquid phase was developed for the prediction of the SO2 removal efficiency, and the calculated values were in reasonable agreement with the experimental values. The study is considered as the one-dimensional prediction of SO2 removal and low-cost application of limestone slurry for commercial FGD technology. [Copyright &y& Elsevier]

[Display omitted] • Fe2+/Fe3+ or N O 2 - / N O 3 - mediated biochar-assisted water electrolysis was studied. • Biochar oxidation reaction (BOR) was enhanced with ions mediation. • Mechanism of anodic oxidation reaction with mediator was deduced. • The activation energy of BOR was reduced by 33.9% and 58.5% with Fe2+ and N O 2 - mediation. The biochar-assisted water electrolysis (BAWE) is a promising method for clean biomass utilization and hydrogen production. But it is limited by the slow anode biochar oxidation reaction (BOR). To enhance the BOR, the mediator of Fe2+/Fe3+ or N O 2 - / N O 3 - was added to the pyrolytic biochar (PB) and tested using electrochemical methods. Both Fe2+ and N O 2 - showed stronger oxidation activity than Fe3+ and N O 3 - , and thereby presented more significant enhanced role on BOR, including the reduction in onset potential and the enlargement of current density. Fe2+/Fe3+ existence resulted in the five-step mechanism such as adsorption, redox reaction in solution, oxidation at electrode surface, and passive films formation on the biochar surface. 0.5 mol/L or less of Fe2+/Fe3+ was suggestable, while the lower acid concentration was necessary to avoid side reaction with N O 2 - existence. The Fe2+/Fe3+ acted as catalysts due to the almost unchanged total iron ions during continuous BAWE process, whereas a high consumption of N O 2 - occurred. The cathode hydrogen production was less influenced by mediator and showed comparable with the theoretical value of Faraday's law. In addition, the activation energy of BOR was significantly reduced with Fe2+ and N O 2 - mediation. The present work provides a favorable strategy for improving BOR and energy-saving production of hydrogen via BAWE process. [ABSTRACT FROM AUTHOR]