The influence of Ni loading on the activity and coke formation of ultrasound-assisted co-precipitated Ni-Al2O3 nanocatalyst in dry reforming of methane

Mesoporous nanocrystalline Ni-Al2O3 powders with different Ni loadings were synthesized via ultrasonic-assisted co-precipitation method and employed in methane dry reforming. The synthesized samples were investigated by BET, XRD, TPR, TPO and SEM analyses. The analyses showed that the increase in nickel loading from 15 wt.% to 25 wt.%, increased the surface area from 171.2 to 188 m(2) g(-1) and further increase in Ni loading has a negative influence on the surface area. It was seen that increasing in Ni loading from 15 wt.% to 33 wt.% decreased the crystallite size and also improved the reducibility of the catalyst. The TPO analysis exhibited that decreasing in Ni loading decreased the content of accumulated carbon. The catalytic results showed an improvement in catalytic activity by the increase in Ni loading. The activity measurements showed that the 25wt.%Ni-Al2O3 exhibited high catalytic performance in CH4 dry reforming.(C) 2016 hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.