Hollow alumina nanospheres as novel catalyst for the conversion of methanol to dimethyl ether

This paper investigates hollow and porous alumina nanospheres that were previously synthesized to be used for the dehydration of methanol to dimethyl ether (DME). As hollow nanostructures possess characteristics such as low density and high surface to volume ratio, their catalytic activity between hollow and porous structure is compared. For this purpose, three most important parameters (acidity, temperature and weight hourly space velocity (WHSV)) affecting the performance of these catalysts were investigated. The catalysts were characterized by scanning electron microscopy (SEM), BET, X-ray diffraction (XRD), and the temperature programmed desorption of ammonia (NH3-TPD) techniques. Results show that the optimum operating condition for hollow alumina nanosphere can be achieved at temperature of 275 °C and WHSV of 20 h^-1 compared with operating condition for porous alumina at temperature of 325 °C and WHSV of 20 h^-1.