Landfills are often used as examples of decadent societies awash in their own waste, but a team of researchers presenting at this year’s meeting of the American Chemical Society thinks differently. Their new method uses ordinary landfill waste to produce energy.
A renewable energy source not often discussed, hydrogen fuel cells are attractive due to their scalability. However, the most common hurdle has been the strategy for reliably creating hydrogen to fill the cells at a low price point. Enter landfills, which contain microbes that naturally produce both methane and carbon dioxide gases: the building blocks for hydrogen creation.
When the naturally occurring methane and carbon dioxide gases react, hydrogen is created. It emits water vapor rather than greenhouse gases when it is burned for energy. The main issue addressed by the study is the inefficiency of the catalysts used for the conversion.
While initially effective, the current generation of catalysts allow carbon, a byproduct of the process, to be deposited in the catalyst, which reduces and ultimately eliminates the utility.
Using a perovskite-type oxide, a component of ceramics, the researchers have been able to develop a new type of highly stable catalyst that removes the resulting carbon as soon as it is formed. The strategy is based on the designs for a previous generation of catalysts – those that help reduce automotive emissions.
The new process allows the hydrogen to be created reliably from landfills, without the previous disruptions of carbon build-up.
The researchers are optimistic that their new catalyst would be an ideal commercialization option and are planning to test it on a larger scale in the future.