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Solid sorbents for carbon capture include a diverse range of porous, solid-phase materials, including mesoporous silicas, zeolites and metal-organic frameworks. These have the potential to function as more efficient alternatives to amine gas treating processes for selectively removing CO2 from large, stationary sources including power stations.〔A. H. Lu, S. Dai, ''Porous Materials for Carbon Dioxide Capture'' Springer, 2014.〕 While the technology readiness level of solid adsorbents for carbon capture varies between the research and demonstration levels, solid adsorbents have been demonstrated to be commercially viable for life-support and cryogenic distillation applications. While solid adsorbents suitable for carbon capture and storage are an active area of research within materials science, significant technological and policy obstacles limit the availability of such technologies. == Overview == (詳細はfossil fuels generates over 13 gigatons of CO2 per year.〔International Energy Agency, ''CO2Emissions from Fuel Combustion: Highlights'' IEA, 2013.〕 Concern over the effects of CO2 with respect to climate change and ocean acidification led governments and industries to investigate the feasibility of technologies that capture the resultant CO2 from entering the carbon cycle. For new power plants, technologies such as pre-combustion and oxy-fuel combustion may simplify the gas separation process. However, existing power plants require the post-combustion separation of CO2 from the flue gas with a scrubber. In such a system, fossil fuels are combusted with air and CO2 is selectively removed from a gas mixture also containing N2, H2O, O2 and trace sulphur, nitrogen and metal impurities. While exact separation conditions are fuel and technology dependent, in general CO2 is present at low concentrations (4-15% v/v) in gas mixtures near atmospheric pressure and at temperatures of approximately 40-60 °C.〔A. Samanta, A. Zhao, G. K. H. Shimizu, P. Sarkar, and R. Gupta ''Industrial & Engineering Chemistry Research'' 2012 ''51'' 1438-1463.〕 Sorbents for carbon capture are regenerated using temperature, pressure or vacuum, so that CO2 can be collected for sequestration or utilization and the sorbent can be reused. The most significant impediment to carbon capture is the large amount of electricity required.〔A. Adragna, "CO2 Capture Could Raise Wholesale Energy Price Eighty Percent" Bloomberg News, Feb. 12, 2014.〕 Without policy or tax incentives, the production of electricity from such plants is not competitive with energy sources.〔NETL, ( "Cost and Performance Baseline for Fossil Energy Plants" Volume 1: Bituminous Coal and Natural Gas to Electricity )〕 The largest operating cost for power plants with carbon capture is the reduction in the amount of electricity produced.〔H. Herzog, J. Meldon, A. Hatton, ("Advanced Post-combustion CO2 Capture" )〕 Steam is diverted from making electricity in turbines to regenerate the sorbent. Thus, minimizing the amount of energy required for sorbent regeneration is the primary motivation behind much carbon capture research. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Solid sorbents for carbon capture」の詳細全文を読む スポンサード リンク
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