Effect of surfactant on structure and performance of catalysts for DME synthesis in slurry bed

Abstract

The Cu–Zn–Al slurry catalysts prepared via modified sol–emulsion–gel method by adding different water-soluble surfactants were studied for CO hydrogenation to produce dimethyl ether (DME) in slurry bed reactor. The results indicated that the catalyst adding Tween80 or PEG600 had higher activity than the catalyst with the PVP additive. All the catalysts had good stability. X-ray diffraction (XRD) results showed that Cu and Cu 2O existed in the pre-reduced Cu–Zn–Al catalysts, while ZnO did not appear. Nitrogen adsorption studies showed that the catalyst prepared with the additives of PEG600 or Tween80 was mesoporous structure with higher specific surface area compared with the one prepared with the additive of PVP. X-ray photoelectron spectroscopy (XPS) results indicated that the Cu/Zn ratio on the surface of all catalysts increased after subject to reduction and reaction. The morphology and size of the catalyst particles could be adjusted by adding water-soluble surfactants.