[thackney]

Fischer-Tropsch process to convert coal to liquid fuel

Do you understand that process goes to gas first, then to liquid? The Sulfur, ash, etc is removed before the liquid fuel is made.

http://www.purdue.edu/discoverypark/energy/assets/pdfs/cctr/outreach/Basics1-CoalGasification-Jun07.pdf

Coal to liquid does not carry all the impurities into the liquid fuel.

[RayChuang88]

True, but converting the coal to a gaseous form is complex and pretty energy intensive. Sure, the Germans did it during World War II, but it was very costly to set up those special refineries to make the aviation-grade petrol from coal. So much so that when the Americans studied the plans for the German refineries, they rejected the idea because the cost to make one gallon of gasoline from coal was WAY higher than refining it from crude oil.