Researchers claim a new technique could transform smelly, air-polluting landfill gas into a fuel cell that can generate clean energy for homes, offices and hospitals. The advance would convert methane gas into hydrogen, an efficient, clean form of energy.
The researchers report is part of the 248th National Meeting of the American Chemical Society (ACS), the world’s largest scientific society.
Hydrogen has recently received a lot of attention as a clean alternative to fossil fuels, which release carbon dioxide, the main greenhouse gas, when burned. In comparison, Hydrogen only emits water vapor when it is burned. This is why some companies are developing hydrogen fuel cells for automobiles and homes.
One excellent way to accomplish this, is to convert another greenhouse gas, methane, to hydrogen by reacting it with carbon dioxide. And the unsightly landfills are excellent sources of these gases, microbes living in the waste produce large amounts of methane and carbon dioxide as a by-product.
However, researchers have been faced with challenges while trying to bring this idea to reality. One big problem has been, finding a proper catalyst, says Fabio B. Noronha, PhD., who is with the National Institute of Technology in Rio de Janeiro, Brazil.
A catalyst is a substance that speeds up processes that would otherwise occur slower. In this case, researchers are using catalysts to help turn methane and carbon dioxide into hydrogen and carbon monoxide. The problem is that carbon, which forms as a contaminant during the process, deposits onto the catalyst.
“The heart of the process for the production of hydrogen from landfill gas is the catalyst, and this can be disrupted by the presence of carbon,” Noronha explains. “Because of carbon deposition, the catalyst loses the capacity to convert the landfill gases into hydrogen.”
He says that to solve this problem, his team developed a new catalyst material that removes the carbon as soon as it is formed. This approach was based on the automotive catalysts developed in the past to control car and truck emissions, he adds. The material is a perovskite-type oxide supported on ceria, which is a component of ceramics.
Currently, the researchers are working on the reaction in the laboratory, however, the new, highly stable catalyst should be ideal for commercialization. As a step in that direction, the team plans to test it on a larger scale using material from a local landfill, says Noronha.