Materials and Technology for Global Carbon Dioxide Recycling -For supply of renewable energy and prevention of global warming
|Koji Hashimoto 1, Naokazu Kumagai 2, Koichi Izumiya 2, Zenta Kato 1|
1. Tohoku Institute of Technology, 6, Futatsuzawa,Taihakuku, Sendai 982-8588, Japan
According to the data of Department of Energy, USA, the primary energy consumption of the world in 1990-2004 increased by a factor of 1.0181 every year. The primary energy consumption per person in developed countries in 2004 was 6.23 times as high as that in developing countries. Thus the sharp increase in primary energy consumption by developing countries is natural and serious global warming cannot be avoided as long as fossil fuel is used. The increase in the world primary energy consumption at the average rate in 1990-2004 will lead to complete exhaustion of oil, uranium, natural gas and coal reserves in 2034, 2040, 2042 and 2054, respectively. In order to avoid such a miserable situation of no fuel and intolerable worming, we have to establish immediately new technology to use only renewable energy for all people in the whole world.We are proposing global carbon dioxide recycling. The electricity necessary for all people in the whole world will be generated by solar cells in the deserts. 4.71023 x 1020 J corresponding to the world total primary energy consumption in 2004 can be generated in the form of electricity by solar cells with 15 % energy conversion in only 1.85 % of the main deserts on the Earth, if 1000 Wm-2 of solar energy are available for 8 hours a day. Because long distance transmission of electricity is not feasible, the electricity will be used for production of hydrogen by seawater electrolysis at nearby desert coasts. Because there are no mass transportation technology and no widely used combustion systems for hydrogen, hydrogen will be converted to methane, that is, the main component of natural gas by the reaction with carbon dioxide at the desert coasts. After combustion of methane carbon dioxide will be recovered and transported back to the desert coasts. Among systems in global carbon dioxide recycling, seawater electrolysis and methane formation by the reaction of carbon dioxide with hydrogen have not been performed industrially. We tailored anodes for oxygen evolution without chlorine formation in seawater electrolysis, energy-saving cathodes for hydrogen production and ideal catalysts for methane formation by the reaction of carbon dioxide with hydrogen with almost 100 % methane selectivity in addition to quite fast conversion. We constructed a prototype plant for global carbon dioxide recycling in 1995 and an industrial scale pilot plant consisting of seawater electrolysis and carbon dioxide methanation in 2003. The latest advance will be reported.
Presentation: Plenary talk at E-MRS Fall Meeting 2007, Plenary session, by Koji Hashimoto
See On-line Journal of E-MRS Fall Meeting 2007
Submitted: 2007-05-07 14:03 Revised: 2007-05-07 14:08