CO Methanation Over SAPO-34 Supported Ni Catalysts

Abstract

This study investigated carbon monoxide methanation with 15 %NiO doped SAPO-34 zeolite-supported catalysts. The SAPO-34 support was produced by hydrothermal synthesis, and nickel oxide was added to the support by impregnation and surfactant-assisted impregnation method, dissolved in different solvents (water, ethanol, acetone, and 1-propanol). Various characterization techniques, N2 physisorption, XRD, SEM, TEM, and FTIR, were used to determine the physical properties of catalysts. XRD analysis showed that synthesizing the catalysts with surfactant reduced the crystallite size. The average crystal sizes of the catalysts synthesized using the impregnation and surfactant-assisted impregnation methods are between 11.3-7.1 nm and 8.9-7.1 nm, respectively. The N2 physisorption analysis showed that the catalysts with the surfactant assisted impregnation method had higher surface areas among the catalysts produced by the two different preparation methods. It was observed that the surface area of the catalyst increased as the boiling point of the solvent increased. Scanning electron microscopy (SEM) analysis exhibited that the particle size of the catalysts with 1-propanol prepared by impregnation and surfactant-assisted impregnation methods are 118 nm and 86 nm, respectively. According to the results, surfactants cause to produce smaller particles. The CO methanation studies showed that the highest CO conversion values were reached with Ni/SAPO-34 catalyst using 1- propanol prepared by impregnation and other method, which gave 19.2% and 21.1% CO conversion to methane at 375C, respectively. The low methane formation rates showed that most of the CO component was adsorbed on the surface, and some were converted to methane.