Preparation of nanosize Cu-ZnO/Al2O3 catalyst for methanol synthesis by phase transfer with metal surfactant .2. Effect of additives and chain length of surfactant

Nanosize Cu-ZnO/Al2O3 catalysts for methanol synthesis were prepared by the metal surfactant phase transfer technique. The effects of chain length of surfactant and additives were studied. It was found that the longer the organic chain of surfactant, the more stable the sol particles and the larger the surface area of catalyst. The decomposition temperature of surfactants with longer chains was also higher. For the preparation of Cu-ZnO/Al2O3, catalyst, the surfactant organic chain should not be longer than 11 carbon atoms. A synergist could be used to improve surfactant efficiency. A stabilizing agent was used to strengthen the stability of sol particles in water. The time needed for oil-water separation was reduced markedly by using a demulsifying agent. The optimal mole ratios of synergist, stabilizing agent, and demulsifying agent to surfactant were, respectively, 0.6, 0.6, and 1. (C) 1996 Academic Press, Inc.