The effect of lanthanum addition on the catalytic activity of γ-alumina supported bimetallic Co–Mo carbides for dry methane reforming

Abstract

The effect of lanthanum addition to c-alumina supported bimetallic carbides has been studied for the reaction of dry methane reforming using four different lanthanum loading levels of 1, 5, 10 and 15 wt% of lanthanum. It has been demonstrated that the addition of lanthanum to supported bimetallic carbides at low loading levels (1 wt%) results in smaller carbide crystallite sizes compared to catalysts containing either no lanthanum or higher lanthanum loading levels (5-15 wt%). Increased lanthanum loading results in increased carbon dioxide desorption at 500-700°C. Reactions indicated that increased lanthanum loading resulted in significantly reduced product yields due to increased reverse water-gas shift activity. All materials exhibited degrees of sintering during the reaction. It was found that cobalt reacted with lanthanum species to form a LaCoO 3 phase. The 1 wt% catalyst possessed superior catalytic properties for dry methane reforming and was tested for 100 h. After an initial loss of activity, the catalyst appeared to stabilise, however, a decrease of *3 % in the H 2 :CO ratio, evidence of carbide crystallite growth and carbon deposition, indicated that a shift in the side reactions had occurred during the reaction.

Combined Magnesia, Ceria and Nickel catalyst supported over γ-Alumina Doped with Titania for Dry Reforming of Methane

“…Although noble metals display high activity and stability, their limited availability and high price have rendered them inappropriate for industrial use [13,14]. On the other hand, the first-row transition metals are cheaper and possess similar activity, but their stability is hampered by carbon deposition and particle sintering [15][16][17][18]. Therefore, development of Ni-based catalysts with high activity and resistance to deactivation due to carbon formation and metal sintering is essential for DRM.…”

Synergistic effect of Promoter addition and Nickel Loading for Catalysed Dry Reforming of Methane

“…formation was observed [18]. This suggests that a new composite has formed as a derivative from the carbon coking and sintering hence deactivating the active sites on Nickel.…”

H2 Production from Methane Reforming over Molybdenum Carbide Catalysts: From Surface Properties and Reaction Mechanism to Catalyst Development

“…They found that Ni−Mo 2 C synthesized by carburizing a coprecipitated (CP) precursor showed higher catalytic activity in the DRM reaction than a mechanically mixed (MM) precursor. During coprecipitation, Ni was incorporated into the NiMoO 4 matrix, avoiding metal 133,138,149 ZrO 2 , 139,140 MgO, 142 La 2 O 3 , 143 and several bimetallic oxides, 144 as described here.…”