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International audience; Methane reforming allows the production of synthesis gas (syngas) which is an important gas mixture feedstock for the production of chemicals and energy carriers. Steam reforming of methane (SRM) and partial oxidation of methane (POM) have been deployed at large industrial scale, while dry reforming of methane (DRM) and more recently tri-reforming of methane (TRM) are intensively studied. TRM simultaneously combines SRM, POM and DRM in a unique process and allows overcoming several weaknesses of each individual methane reforming process: e.g. regulation of the molar ratio of H2/CO by controlling feed composition; adaptation to the variation in biogas composition as renewable resource. TRM process strongly requires a solid catalyst. To date, the design of efficient TRM catalysts remains a challenge. This work reviews recent achievements on the development of catalysts for TRM, and provides a guideline for future work related to TRM catalysts.

International audience; Oxidative pyrolysis is a key step in the autothermal operation of many fixed-bed reactors for staged gasification and advanced carbonisation. In these reactors, biomass is converted into charcoal, condensates and permanent gases inside a moving Oxidation Zone (OZ) which also produces energy to self-sustain the process. Oxidative pyrolysis of three different biomass types: pine wood, miscanthus and wheat straw pellets, was performed in a batch 20 cm diameter fixed bed reactor. Results showed that the OZ consumed 11% to 14% of the stoichiometric air to self-sustain the process and reached a peak temperature around 720 °C whatever the biomass. The propagation velocity and thickness of the OZ were inversely proportional to the ash content and to the bulk density of the biomass. Ash was also shown to influence the yield and composition of the resulting products due to a catalytic effect on primary and secondary pyrolysis reactions.

International audience; Oxidative pyrolysis, in which heat is provided by the partial oxidation, occurs in many fixed bed reactors of air staged gasification and advanced carbonization processes. In these reactors, an Oxidation Zone (OZ) propagates and separates the virgin biomass from the produced char, and self-sustains the process. To investigate the energy transfer efficiency and to characterize the OZ features, oxidative pyrolysis was performed in a 20 cm diameter fixed bed reactor with Wheat straw pellets. Temperatures and biomass bed height were measured continuously during the experiment. The OZ propagated at 0.41 cm/min and consumed about 11 % of the biomass. The role of bed compaction on the effective propagation velocity was highlighted. Char yield was measured to 28.6 % and char accounted for 39.56 % of the total energy content of the Wheat straw. Maximum temperature in the bed reached 780°C. This paper proposes a new insight into the OZ features when it propagates in a biomass fixed bed.

International audience; This paper focuses on the valorization of calcium carbonate-based solid wastes for theremoval of hydrogen sulfide from gas phase. Two solid wastes taken from industrial sites for theproduction of sodium carbonate and sodium bicarbonate by the Solvay process® were analyzedby different physico-chemical methods. Calcium carbonate was found as the main component ofboth the solid wastes. Trace amounts of other elements such as Mg, Al, Fe, Si, Cl, Na etc. werealso present in these wastes. These solid wastes showed higher sorption activity for the removalof H2S, compared to a pure commercial calcium carbonate. The contact time was found as animportant parameter for the complete H2S uptake. The addition of well-dispersed iron-basedparticles could be carried out by the standard incipient wetness impregnation method. Sorbentcontaining 1 wt.% of spiked iron had the similar sorption behavior compared to a commercialactivated carbon, in terms of reactivity and reactivation possibility.