Zirconia–sugarcane bagasse fly ash as a novel solid acid nanocatalyst for selective dehydration of methanol to dimethyl ether.

In the current study, two series of catalysts were synthesized and characterized by various physicochemical techniques. In the first series of catalysts, a chemical precipitation method was used for loading 1–20 wt. % ZrO2 on the surface of sugarcane bagasse fly ash (SCBFA) with the goal of finding out the optimal ZrO2 loading. In the second series, the 20% ZrO2/SCBFA composition was modified by (1–10 wt. %) SO42− by wet impregnation method. The acidity of these catalysts was determined through the dehydration of isopropyl alcohol and the chemisorption of pyridine and 2,6-dimethyl pyridine. The catalytic efficiency for the dehydration of methanol to dimethyl ether (DME) in a fixed-bed reactor at atmospheric pressure was investigated. A ~ 95% yield toward DME is maximized over the 10% SO42−/20% ZrO2/SCBFA catalyst at a reaction temperature of 400°C. Additionally, it maintained nearly the same efficiency over a 90-h period and demonstrated outstanding long-term stability. The specific surface area and the acidity are the most important factors responsible for enhancing the catalytic performance in this reaction. Our study reflects that SCBFA-supported zirconia and that modified with SO42− are low-cost, effective, eco-friendly, and recyclable catalysts that are highly suited to apply for production of DME from methanol. [ABSTRACT FROM AUTHOR]