Innovative Method for CO2 Fixation and Storage

The concentration of CO 2 in Earth’s atmosphere has been gradually increasing since the Industrial Revolution, primarily as a result of the use of fossil fuels as energy sources. Although coal and oil have been vital to the development of modern civilization, it is now recognized that atmospheric CO 2 levels must be reduced so as to avoid the serious effects of climate change, including natural disasters. Consequently, there is currently significant interest in developing suitable methods for the fixation of CO2 in the air and in exhaust gases. The present work demonstrates a simple yet innovative approach to the chemical fixation of extremely low and also very high CO 2 concentrations in air, such as might result from industrial sources. This process is based on the use of aqueous solutions of the water soluble compounds NaOH and CaCl 2 , which react with CO 2 to produce the harmless solids CaCO 3 (limestone) and NaCl (salt) via intermediates such as NaHCO 3 and Na 2 CO 3 . The NaCl generated in this process can be converted back to NaOH via electrolysis, during which H2 (which can be used as a clean energy source) and Cl 2 are produced simultaneously. This system provides a safe, inexpensive approach to CO 2 fixation and storage.