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The methanol economy is a suggested future economy in which methanol replaces fossil fuels as a means of energy storage, ground transportation fuel, and raw material for synthetic hydrocarbons and their products. It offers an alternative to the proposed hydrogen economy or ethanol economy. In the 1990s Nobel prize winner George A. Olah started to advocate the methanol economy and in 2006 he and two co-authors, G. K. Surya Prakash and Alain Goeppert, published a book around this theme.〔''Beyond Oil and Gas: The Methanol Economy '', George A. Olah, Alain Goeppert, G. K. Surya Prakash, Wiley-VCH, 2006〕 In these publications, they summarize the state of our fossil fuel and alternative energy sources, their availability and limitations before suggesting a new approach in the so-called methanol economy. Methanol is a fuel for heat engines and fuel cells. Due to its high octane rating it can be used directly as a fuel in flex-fuel cars (including hybrid and plug-in hybrid vehicles) using existing internal combustion engines (ICE). Methanol can also be used as a fuel in fuel cells, either directly in Direct Methanol Fuel Cells (DMFC) or indirectly (after conversion into hydrogen by reforming). Methanol is a liquid under normal conditions, allowing it to be stored, transported and dispensed easily, much like gasoline and diesel fuel is currently. It can also be readily transformed by dehydration into dimethyl ether, a diesel fuel substitute with a cetane number of 55. Methanol is already used today on a large scale (about 37 million tonnes per year)〔''Product Focus: Methanol'', ''Chemical Week'' May 23, 2007, Page 29〕 as a raw material to produce numerous chemical products and materials. In addition, it can be readily converted in the methanol-to-olefin (MTO) process into ethylene and propylene, which can be used to produce synthetic hydrocarbons and their products, currently obtained from oil and natural gas. Methanol can be efficiently produced from a wide variety of sources including still-abundant fossil fuels (natural gas, coal, oil shale, tar sands, etc.), but also agricultural products and municipal waste, wood and varied biomass. More importantly, it can also be made from chemical recycling of carbon dioxide, which Carbon Recycling International has demonstrated with its first commercial scale plant.〔(【引用サイトリンク】title=First Commercial Plant )〕 Initially the major source will be the CO2 rich flue gases of fossil-fuel-burning power plants or exhaust from cement and other factories. In the longer range however, considering diminishing fossil fuel resources and the effect of their utilization on earth's atmosphere, even the low concentration of atmospheric CO2 itself could be captured and recycled via methanol, thus supplementing nature’s own photosynthetic cycle. Efficient new absorbents to capture atmospheric CO2 are being developed, mimicking plants' ability. Chemical recycling of CO2 to new fuels and materials could thus become feasible, making them renewable on the human timescale. Methanol may be viewed as a compact way of storing hydrogen. One m3 of methanol at ambient pressure and temperature contains 1660 Nm3 (normal cubic metres) of hydrogen gas (H2). This may be compared to liquid hydrogen where one m3 of liquid hydrogen (LH2) at -253 °C contains only 788 Nm3 of hydrogen gas 〔Source: WPI-080905 (Westerink Procédé Industriel)〕 Trinidad and Tobago is currently the world's largest methanol exporter, with exports mainly to the United States 〔http://www.ogj.com/articles/2014/09/ryder-scott-trinidad-and-tobago-s-gas-reserves-fell-in-2013.html〕 ==Uses of methanol in a methanol economy== 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「methanol economy」の詳細全文を読む スポンサード リンク
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