An approach of CO2 capture technology for mitigating global warming and climate change-an overview

Energy and the environment are two of the most important issues this century. More than 80 % of our energy comes from the combustion of fossil fuels, which will still remain the dominant energy source for years to come. It is agreed that carbon dioxide produced from the combustion process to be the most important anthropogenic greenhouse gas leading to global warming. Atmospheric CO2 concentrations have indeed increased by almost 100 ppm since their pre-industrial level, reaching 384 ppm in 2007 and still increasing with a total annual emission of over 35 Gt. Prompt global actions to resolve the CO2 crisis is therefore needed. To pursue such an action, we are urged to save energy without the unnecessary production of carbon emissions and to use energy in more efficient ways, but alternative methods to mitigate the greenhouse gas have to be considered. There is a large energy penalty in the proven technology of chemical absorption/stripping of CO2 using amine solvents. The aim in this study is to develop fast catalytic absorption/ desorption of CO2 at low temperatures using water as solvent. The naturally occurring zinc metallo-enzyme carbonic anhydrase (CA) can concentrate CO2 using a reversible Hydration /dehydration cycle at neutral pH and at ambient temperatures. Some tripodal complexes of zinc (II), and other metals mimic the CA catalytic process, which proceeds by hydration of CO2 to bicarbonate followed by the reverse dehydration of the bicarbonate to regenerate CO2. This Minireview highlights some recent promising research activities and their prospects in the areas of carbon capture and storage and chemical fixation of CO2 in constructing a future low-carbon global economy with reference to energy