Recent trends and fundamental insights in the methanol-to-hydrocarbons process

The production of high-demand chemical commodities such as ethylene and propylene (methanol-to-olefins), hydrocarbons (methanol-to-hydrocarbons), gasoline (methanol-to-gasoline) and aromatics (methanol-to-aromatics) from methanol—obtainable from alternative feedstocks, such as carbon dioxide, biomass, waste or natural gas through the intermediate formation of synthesis gas—has been central to research in both academia and industry. Although discovered in the late 1970s, this catalytic technology has only been industrially implemented over the past decade, with a number of large commercial plants already operating in Asia. However, as is the case for other technologies, industrial maturity is not synonymous with full understanding. For this reason, research is still intense and a number of important discoveries have been reported over the last few years. In this review, we summarize the most recent advances in mechanistic understanding—including direct C–C bond formation during the induction period and the promotional effect of zeolite topology and acidity on the alkene cycle—and correlate these insights to practical aspects in terms of catalyst design and engineering. The conversion of methanol — which can be produced from non-fossil resources — to important chemical commodities such as olefins and aromatics allows for the diversification of organic feedstocks beyond petrochemicals. This Review covers recent discoveries about the mechanism of this process and discusses how these link to practical aspects in reaction engineering.