Researchers from Wetsus, the center for excellence for sustainable water technology in Leeuwarden, the Netherlands, established a method to create an electrical current from carbon dioxide (CO2) using a combination of membranes and water.
The study, published in the Journal Environmental Science & Technology Letters, provides a mean for handling the greenhouse gas from electric power-generating plants, and prevents it from being released in the atmosphere.
Carbon dioxide is one of the main causes for global warming. Annually, billions of tons of the gas are released in the atmosphere from electricity generating power plants, home and commercial heating, and other smokestacks.
The new technology is designed to initiate a chemical reaction between CO2 and water or other liquids in order to produce electricity. Under laboratory conditions, the scientists were able to estimate that around 1,570 kilowatts of additional electricity can be generated annually, if the method is used to harvest the wasted CO2. This amount was found to be around 400 times the power generated by the Hoover Dam.
The laboratory testing was conducted using filled water tanks. One side of the tanks was equipped with a membrane, which allows positive ions to pass through, while on the other side of the tank, the researchers placed another membrane to allow penetration of only the negative ions. Electrodes were placed beyond the membranes.
Pumping carbon dioxide through the water resulted in separation of the CO2 molecule into positive hydrogen ions, and negative bicarbonate ions. The membranes then controlled which ions can pass through, creating a net flow of electrons from one side of the tank to the other.
The team, led by Bert Hamelers, is now exploring the possibility of expanding the process from laboratory to industrial scale. If successful, the study would provide an efficient way to generate electricity from what is considered one of the most dangerous gases to the environment.