Humans generate billions of tons of carbon dioxide every year. A group of researchers in the Netherlands asked whether it would be better to use the gas to generate power rather than letting it end up in the atmosphere, where it can do more harm than good.
At Wetsus, the center for excellence for sustainable water technology in Leeuwarden, Bert Hamelers and his team came up with the idea of using a combination of membranes and water to pull current out of CO2. They describe the idea in the journal Environmental Science & Technology Letters.
To get the water out of the CO2, the scientists set up a tanks filled with water. On one side of the tank, they put a membrane that allows positively charged ions to pass through and on the other side, they put a membrane that allows only negatively charged ions to pass through. Beyond the membrane is an electrode. When the carbon dioxide is pumped through the water it separates into positive hydrogen ions and negatively charge bicarbonate. Since the membranes only allow one kind of ion through, a net flow of electrons — or current — move from one side to the other.
In the paper, Hamelers estimates that harvesting all the carbon dioxide from homes and power plants could produce about 1,570 terawatts of additional electricity annually — about 400 times the annual electrical output of the Hoover Dam. And it wouldn’t add any more CO2 to the atmosphere.
The next steps will be to see if the process can be scaled up form lab-bench sizes and work out how to capture and separate the CO2 at industrial scales. It certainly gives a new meaning to recycling.
via American Chemical Society, Environmental Science & Technology Letters
Credit: Wikimedia Commons