Two diverging paths for clean fuel.

Discovered a hundred years ago, the Fischer-Tropsch synthesis (1) has recently been considered as a possible route to produce liquid fuels and chemical building blocks without the use of fossil sources. This chemical reaction converts syngas—a mixture of carbon monoxide and hydrogen—to commercially important chemicals, such as light olefins (2) and long-chain hydrocarbons, through a surface polymerization reaction on cobalt or iron catalysts (3). However, hydrogen can form water as a by-product, and carbon monoxide can lead to carbon dioxide production. Indeed, the Fischer-Tropsch synthesis produces more unwanted derivatives than hydrocarbons. On pages 516 and 494 of this issue, Cai et al. (4) and Gao et al. (5), respectively, report strategies to maximize the incorporation of hydrogen and carbon atoms into hydrocarbon compounds, offering sustainable routes to liquid fuel production with improved efficiency. [ABSTRACT FROM AUTHOR]