Anti‐Coking Ni/SiO₂ Catalyst for Dry Reforming of Methane: Role of Oleylamine/Oleic Acid Organic Pair

Abstract

Abstract We demonstrate the synthesis of silica‐supported Ni catalyst in the presence of oleylamine (OAm) and oleic acid (OAc) as the ligand and surfactant. Compared with OAm or OAc alone, Ni/SiO 2 prepared with OAm/OAc organic pair showed a much smaller Ni particle, a much stronger metal–support interaction (MSI), an enhanced initial conversion of both CO 2 and CH 4 and a prolonged stability over 16 h with zero carbon deposition. How the OAm/OAc organic pair affects the catalyst formation mechanism is proposed: OAc intimately interacts with silica by hydrogen bond formed between the carboxylic group and silanol group; OAm forms a complex with Ni and promotes the adsorption of Ni on silica through the basic property of amine ligand; amide formation between the carboxylic group of OAc and the amine group of OAm makes use of both additives; in addition, a stronger steric hindrance is given by the more complex aliphatic chain network of the pair, retarding the growth of Ni particles.