Fuel for thought

Engineers at Purdue University have developed a new way of producing hydrogen for fuel cells.

The new technique combines two previously known methods for producing hydrogen. And although the previous methods have limitations making them impractical when used alone, those drawbacks are overcome when the methods are combined, according to Arvind Varma, the head of Purdue's School of Chemical Engineering.

One of the methods was invented by Herbert Brown, who discovered a compound called sodium borohydride during World War II. The compound contains sodium, boron and hydrogen. He later developed a technique for producing hydrogen by combining sodium borohydride with water and a catalyst. The method, however, has a major drawback - it requires expensive catalysts such as ruthenium.

The other method involves a chemical reaction in which tiny particles of aluminium are combined with water in such a way that the aluminium ignites, releasing hydrogen during the combustion process. This method does not require an expensive catalyst, but it yields insufficient quantities of hydrogen to be practical for fuel cell applications.