Syngas from CO2 reforming of coke oven gas: Synergetic effect of activated carbon/Ni–γAl2O3 catalyst

The CO2 reforming of coke oven gas for the production of synthesis gas has been studied over an activated carbon, an in-lab prepared Ni/Al2O3 catalyst and physical mixtures of both materials in different proportions (AC + Ni) at 800 °C. It was found that there are two possible coexisting reaction pathways: the direct dry reforming of methane (decomposition of methane followed by gasification of the carbon deposits) and the reverse water gas shift reaction followed by the steam reforming of methane. If the process is carried out with the physical mixtures AC + Ni, there is a synergetic effect between both materials. The experimental conversions are higher than the conversions predicted by the law of mixtures, whereas the production of water is lower, resulting in a higher selectivity. The mixtures also showed a lower loss of porosity than when the activated carbon and the in-lab prepared Ni/Al2O3 were used individually. Therefore, the combination of these materials may produce catalysts that are more resistant to deactivation. The synthesis gas obtained was analyzed and it was found suitable for the production of methanol.

► Two different reaction paths have been found: direct dry reforming and reverse water gas shift followed by steam reforming. ► The use of mixtures activated carbon + Ni/Al2O3 give rise to a synergetic effect over conversions and water production. ► The mixtures activated carbon + Ni/Al2O3 showed a higher resistance to textural properties loss. ► The synthesis gas obtained is suitable for methanol production.