A reduction of CO2 emissions from the use of fossil fuel is the primary purpose of carbon dioxide capture and storage (CCS). CO2 is captured directly form the industrial source, concentrated into a pure form, and then pumped deep underground for long-term storage. It has also been suggested that CO2 can be stored in the ocean as an alternative storage in underground geological formations. CCS can contribute up to 20% of needed CO2 reductions, on par with expected reductions from efficiency improvements and large -scale deployment of renewable energy resources. carbon dioxide can be captured directly from industrial sources by three methods, such as post-combustion capture, pre-combustion capture, or combustion of fossil fuels in a pure oxygen environment. Post-combustion capture separates CO 2 from exhaust gas, which consists primarily of a mixture of N 2 and CO2, using chemical solvents such as monoethanolamine.