Activity and stability of Ni/magnesium slag catalysts enhanced by plasma pretreatment for toluene steam reforming

Abstract

This study investigated the influence of plasma pretreatment on the catalytic performance of a nickel-based catalyst supported by magnesium slag (MS) in the catalytic steam reforming of toluene. The catalyst obtained after plasma pretreatment achieved the highest toluene conversion rate of 99.11 % and the substantial hydrogen yield of 3165.02 mL/g after 6 h of reaction. Additionally, at the end of the reaction, the toluene conversion rate of the plasma-pretreated catalyst was 92.56 %, which was 38.19 % higher than that of the calcined catalyst. Plasma pretreatment significantly enhanced the activity and stability of Ni-based catalyst in toluene steam reforming. Characterization results indicated that plasma treatment promoted the migration of metal species from pores to the external surface of the support and facilitated the formation of smaller Ni particles with higher dispersion. Therefore, plasma treatment exposed more active sites and enhanced the catalytic activity. Furthermore, plasma pretreatment improved the interaction between Ni and the support, generated more Ni(111) crystal planes, reduced the formation of filamentous carbon, accelerated the removal of carbon deposits, and thus enhanced the catalyst stability.