Scientists at the University of Delaware are developing a new low-cost material for hydrogen storage—carbonized chicken feathers (CCFF)—that they say could meet the DOE requirements for hydrogen storage and are competitive with carbon nanotubes and metal hydrates at a tiny fraction of their cost. Their research was presented at ACS Green Chemistry Institute’s 13th Annual Green Chemistry & Engineering Conference on 23 June.
The Department of Energy’s (DOE) 2010 and 2015 hydrogen storage targets are 6 wt% and 9 wt% (gravimetric capacity); 45 and 81 grams H2 per L (volumetric capacity); and $4 and $2 per kWh (storage cost), respectively.
In order to solve the hydrogen storage problem, various kinds of nano-structured materials have been investigated and produced, none of which currently fulfill these targets entirely. Their disposal methods and degradability are still somewhat uncertain. Additionally, the prices of these materials are extremely expensive. It is crucial that the material that will serve as a hydrogen adsorbent in fuel cell vehicles is cheap and is environmentally benign.
The goal of University of Delaware project is to develop new low cost hydrogen storage substrates from an abundant waste material (6 billion lbs/yr in US): chicken feathers.
Chicken feather fibers are mostly composed of keratin, a natural protein that forms strong, hollow tubes. When chicken feathers are heat-treated by controlled pyrolysis, hollow carbon microtubes are formed with nanoporous walls. Their specific surface area increases up to 450 m2/g by the formation of fractals and micropores thus enabling more hydrogen adsorption than raw (untreated) feather fibers. The protein also creates crosslinks, which strengthen its structure.
The net result is carbonized chicken feather fibers, which can absorb as much or perhaps more hydrogen than carbon nanotubes or metal hydrides, according to Dr. Richard Wool, professor of chemical engineering and director of the Affordable Composites from Renewable Resources program at the University of Delaware in Newark.
Using carbonized chicken feathers would only add about $200 to the price of a car, according to Wool. By comparison, making a 20-gallon hydrogen fuel tank that uses carbon nanotubes could cost $5.5 million; one that uses metal hydrides could cost up to $30,000, Wool says. Wool estimates that it would take a 75-gallon tank to go 300 miles in a car using carbonized chicken feather fibers to store hydrogen. He says his team is working to improve that range.
The research was presented by Erman Senöz, a graduate student in the Department of Chemical Engineering at the University of Delaware in Newark.
In addition to hydrogen storage, Wool and his colleagues are working on ways to transform chicken feather fibers into a number of other products including hurricane-resistant roofing, lightweight car parts and bio-based computer circuit boards.
Hydrogen Storage On Carbonized Chicken Feather Fibers Erman Senöz, University of Delaware; Richard P. Wool, University of Delaware