MgAl2O4 with CaO in supported Ni and Ni–Co catalysts – impact on CO2 reforming of CH4

Abstract

ABSTRACT To obtain insight into the effect of promoter–support interactions in CO2 reforming of CH4, a series of Ni and Ni–Co (3:1) catalysts were prepared over modified-MgAl2O4 and MgAl2O4. The prepared samples were characterised and investigated for dry reforming of methane reactions at 873 K and 1 atm. From XRD, it appears that CaO, in a specified amount, is an appropriate modifier to retain the active metallic phase of catalyst and also prevents the formation of a solid solution of itself with the metal oxides during catalyst synthesis. From activity results, enhancement in catalytic activity was observed for Ni and Ni–Co catalysts supported over modified-MgAl2O4 support due to the presence of new and more number of active metal sites. For 100Ni–2.5CaO/MgAl2O4 catalyst, initial CH4 conversion was 1.3 times greater than 100Ni/MgAl2O4. For Ni–Co catalysts comparable results were observed over modified-MgAl2O4 and MgAl2O4 supports. Moderately active carbon species were formed during dry reforming of methane reaction and the presence of new and more number of basic sites helped to minimise carbon deposition. Highlights Incorporation of a metal oxide in appropriate composition proves to be more chemically active than MgAl2O4 Ni–Co synergy exhibited higher catalytic activity Formation of new adsorption site due to support modification Improvement in H2: CO ratio was observed after addition of CaO Similar kind of carbon formation over both the series and Methane decomposition reaction is the source