Higher CO 2 absorption using a new class of calcium hydroxide (Ca(OH) 2 ) nanoparticles

With rising atmospheric carbon dioxide (CO 2 ) concentrations globally, there is an urgent need for highly efficient CO 2 capture technologies. This report introduces an innovative technology to remove CO 2 of point sources using calcium hydroxide (Ca(OH) 2 ) nanoparticles of 10 nm. Superior to regular CO 2 absorption methods, the nano-Ca(OH) 2 chemically increased reactive surface area and gas retention time of the scrubbing system. Experimental data show that CO 2 absorption capacity of the nano-suspension was over 8 times higher than that of the regular Ca(OH) 2 particles of 2 µm in size. In addition to CO 2 removal, nano-Ca(OH) 2 also has high potential to treating acidic gases such as HCl, SO x , or NO x , for improving air quality and offsetting the global warming trend. This is the first study on using Ca(OH) 2 nanoparticles for efficient CO 2 capture.