Effect of glow discharge plasma on rhodium-based catalyst for oxygenates synthesis

Rhodium-based catalysts were prepared by impregnation,treated with glow discharge plasma,character-ized by X-ray diffraction,X-ray photoelectron spectroscopy,H2 temperature-programmed reduction,H2 temperature-programmed desorption and CO temperature-programmed desorption,and investigated for oxygenate synthesis from CO hydrogenation.Based on the characterization results,plasma treatment endowed the samples with smaller particle size,higher dispersion of active components,and an enrichment of active components on the surface as well.As a result,the reducibility and adsorption properties were modified.In cata-lytic tests,the catalytic activity for CO hydrogenation over the samples treated by plasma was improved remarkably:the conversion of CO and the yield of oxygenates increased at most by a factor of 78.62%and 51.96%,respectively,while the selectivity of ethanol and methanol in the oxygenates was enhanced as well.