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Charcoal was gasified using air and oxygen as well as with mixtures of oxygen and steam, aiming to produce a gas stream with high hydrogen content. The effects of the equivalence ratio (ER) and steam-to-carbon ratio (S/C) on carbon conversion, producer gas yield, gas heating value, and composition as well as on the apparent energy efficiency (AEE) of the process were studied. The gasification experiments were performed in a laboratory-scale fluidized bed rig working at 1173 K and atmospheric pressure and using γ-Al2O3as bed material. Results showed that, on a N2-free basis, the composition of the producer gas obtained by gasification with air and pure oxygen were comparable when using the same ER. Furthermore, carbon fraction converted into gas improved when ER was increased from 0.25 up to 0.35, as well as when the S/C was increased to 0.625. The highest producer gas yield was obtained using ER = 0.35 and S/C = 0.625, while the highest hydrogen concentration in the produced gas was achieved using ER = 0.25 and S/C = 0.625. The highest hydrogen yield (0.412 N m3/kg charcoal) and the highest AEE (33.43%) were achieved by using S/C = 0.625 and ER = 0.3 (oxygen). The autothermal gasification of the charcoal was possible in the experimental rig used in this work by selecting ER = 0.3 and S/C = 0.5, allowing the production of a gas with a heating value of 8.3 MJ/Nm3while reducing the carbon conversion into gas to 49.4 wt %.

CO elimination is an important step for the proper management of gaseous effluents from various processes, thus avoiding adverse impacts on the environment and human health. In this study, different bimetallic Al2O3-supported CoMo catalysts have been developed, characterized, and tested in the CO oxidation reaction, based on their respective oxides, carbides, and nitrides phases. The parent CoMo-oxide catalyst (CoMo) was prepared by impregnation and then transformed to its carburized (CoMoC) and nitrided (CoMoN) forms using temperature-programmed reaction methods under controlled atmospheres of CH4/H2and NH3, respectively. The catalytic results demonstrate that the CoMoC catalyst exhibits higher activity compared to its CoMoN counterpart, and both are more active than the parent CoMo catalyst. Furthermore, the reduction temperature and space velocity were key process factors, which notably influenced activity and kinetic parameters, while the increase of reduction time does not seem to improve catalytic behavior. These results were associated with a better metal dispersion, and relatively higher reduction grade and metallic surface area on the carbides and nitrides, opening the possibility that new adsorption sites may be created. The catalytic results compare favorably with other non-noble metal catalysts, such as Cr-, Cu-, Fe-, and Ni-based samples, and highlight the potential of using carbides and nitrides as alternative formulations to enhance the performance of CO oxidation.