The most popular commercial catalyst combines iron and chromium to produce hydrogen, but the chromium waste is dangerous to human health and excessively expensive to dispose.

The new catalyst extracts hydrogen from carbon monoxide and water using iron, aluminium and other metals. As carbon monoxide can be extracted from coal, it is hoped the new catalyst will accommodate the extraction of hydrogen from coal without toxic metal run-off, said Professor Umit Ozkan from Ohio State University in the USA

“Hydrogen is the ultimate fuel,” she said.

“At the same time we have very large coal reserves. If we could somehow go from coal to hydrogen, we could put those reserves to use in a new way.”

The first step to creating hydrogen requires the gasification of coal into a carbon-monoxide rich stream. The carbon monoxide is then mixed with water to remove the hydrogen.

Ozkan’s team examined the chemical structure of chromium for an understanding of its success as a hydrogen catalyst, leading her to substitute it with aluminium and similar metals to create an efficient, chromium-free catalyst.

“What is important is not only which metals are used but how these metal molecules fit together. We believe the specific way we prepare the catalyst is a key factor in its superior performance,” Ozkan said.

“This performance was maintained when we tested the catalyst using a feed mixture similar to what is produced from coal gasification.”