Hydrogen fuel recipe 'like Prometheus stealing fire'

A group of US researchers say they’ve developed a “one-pot” process for generating hydrogen fuel from cellulosic plant waste, water and a cocktail of enzymes.

The “recipe” produces hydrogen gas that’s pure enough to power a fuel cell, says the team of scientists from Virginia Tech, Oak Ridge National Laboratory (ORNL) and the University of Georgia.

The novel process combines 14 enzymes and one coenzyme with non-food-based plant waste and 32-degree C water. The result: hydrogen production as fast as that yielded by natural hydrogen fermentation and an output of chemical energy that’s actually greater than the chemical energy stored in the plant-based sugars themselves. The combination, the research team says, produces the highest reported hydrogen yield yet from cellulosic materials.

“In addition to converting the chemical energy from the sugar, the process also converts the low-temperature thermal energy into high-quality hydrogen energy — like Prometheus stealing fire,” said Percival Zhang, assistant professor of biological systems engineering in the College of Agriculture and Life Sciences at Virginia Tech. “If a small fraction — 2 or 3 percent — of yearly biomass production were used for sugar-to-hydrogen fuel cells for transportation, we could reach (global) transportation fuel independence.”

“It is exciting because using cellulose instead of starch expands the renewable resource for producing hydrogen to include biomass,” added Jonathan Mielenz, leader of the Bioconversion Science and Technology Group at ORNL.

While the team used wood chip material in its experiments, the process could also be applied to crop waste or switchgrass, the researchers say.