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!!!last question on ethanol!!! (1 Viewer)
- Thread starter x-ray1018
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pLuvia
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Because ethanol being made from raw materials from CO2, water and sunlight using glucose, and when it is burnt it returns to CO2 and water which can reconverted into ethanol
So it's basically using the same CO2 it used to make it in the first place
So it's basically using the same CO2 it used to make it in the first place
In addition to what pLuvia said, The CO2 is produced with water from the combustion of ethanol. The carbon is cycled back to be used by crops during photosynthesis to produce more sugar. Therefore there is no net release of CO2 into the atmosphere. However when petrol burns, al of the carbon dioxide released into the atmosphere adds to the greenhouse gas emissions.
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The equation Riviet posted is photosynthesis. With sunlight, carbon dioxide and water, glucose is made in plants, and oxygen released.mitsui said:
In some plants (wheat and grain plants) this glucose will be used in the fermentation process to make ethanol. When the ethanol is used as a fuel, it undergoes complete combustion to produce carbon dioxide and water - exactly what the glucose was made of.
In this sense, this is a cycle. The products of burning ethanol is exactly the reagents of the glucose that is used to make the ethanol. I hope that's not too confusing.
By the way, you should note that ethanol is not technically a greenhouse neutral gas. Even though it releases carbon dioxide and water upon combustion, large amounts of energy is put into distillation processes. This, in a way, cancels out the energy ethanol saves.