Hydrogen production by methanol reforming on NiAl layered double hydroxide derived catalyst: Effect of the pretreatment of the catalyst

This paper presents the results of the steam reforming of methanol on an as-prepared NiAl-layered double hydroxide catalyst pretreated in two different atmospheres and then the reaction at a high temperature of 390 ∘ C with feed having various steam-to-methanol ratios. The product composition was found to vary significantly with the pretreatment atmosphere. High activity and stability with high selectivity for CO2 and H2 and low level CO and no methane formation in a broad range of the H2O/CH3OH ratio was observed when the catalyst was preheated in the diluted H2 stream. Whereas in the case of pretreatment in the reactive stream of the mixture of steam and methanol, the formation of methane and its increase with more steam in feed was obtained and with time on line the catalyst deactivated with an increase in CO formation and decreases in CO2, H2 and CH4 production. A catalyst with optimal ratio of ionic Ni in different chemical environment is suggested to obtain an active, selective and stable reforming catalyst.