Alcohol fuels for engines

In the book "Beyond Oil and Gas," George A. Olah, Alain Goeppert, and G. K. Surya Prakash do a great job in arguing how methanol may be synthesized not only from the usual 2H₂ + CO CH₃OH route, but also via carbon dioxide-hydrogen synthesis and hopefully before long, 2CH₄ + O₂ 2CH₃OH (C&EN, Oct. 2, page 51).

However, the authors tend to oversell methanol as an automotive fuel. While taking a course on engines at Lawrence Technological University, Southfield, Mich., as part of the automotive engineering curriculum, I chose as my class project the problems and potential of methanol as an alternative fuel. I have not become totally disillusioned with CH₃OH, but I am more aware of problems such as engine wear resulting from formation of corrosive acids and cold-starting issues.

I believe a possible dark horse in the race for a standard alternative fuel for spark-ignition engines is neither methanol nor ethanol, but rather a mixture of methanol, ethanol, propanol, and butanol. This mixture of alcohols could be formed by passing carbon monoxide and hydrogen over a suitable catalyst.

The ideal alternative fuel lends itself to high efficiency and low emissions in automotive engines and is also easy to produce in quantity from readily available raw materials or biomass. Methanol does have some virtues in both the aforementioned criteria. I think a mixture of methanol, ethanol, propanol, and butanol might be a better fuel for engines and, like methanol, can be readily synthesized from anything one can gasify to create a hydrogen-carbon monoxide mixture.

Alex Kovnat
West Bloomfield Township, Mich.