The catalytic reforming of liquid fuels offers a solution to supplying hydrogen to fuel cells while avoiding the safety and storage issues related to gaseous hydrogen. Existing catalytic support structures, however, tend to break down at the high temperatures needed to prevent fouling of the catalytic surface by soot.
"These novel materials show great promise for the on-demand reforming of hydrocarbons such as diesel fuel into hydrogen for portable power sources," said Paul Kenis, a professor of chemical and biomolecular engineering at Illinois.
To be useful for hydrocarbon fuel reforming, a catalyst support must have a high surface area, be stable at high temperatures, and possess a low pressure drop.
"Our new materials satisfy all three key requirements," said Kenis, who also is a researcher at the Beckman Institute for Advanced Science and Technology. "They have a large surface area created by a network of interconnected pores. They can operate at temperatures above 800 degrees Celsius, which prevents the formation of soot on the catalytic surfaces. And they have a low pressure drop, which means it takes less pressure to push the fuel through the catalyst."
To demonstrate the use of these materials as catalyst supports, the researchers coated samples of the porous structure with ruthenium. The structure was then incorporated within a stainless steel housing, where it successfully stripped hydrogen from ammonia at temperatures up to 500 degrees Celsius. In work not yet published, Kenis and his colleagues incorporated the structure in a ceramic housing, which enabled the successful decomposition of ammonia at operating temperatures up to 1,000 degrees Celsius.
COMPAMED.de; Source: University of Illinois at Urbana-Champaign