The Formula
From Grass to GasStep 1: Thermochemical treatment The raw plant feedstock is treated with chemicals — often dilute sulfuric acid — to break down cell walls and make the cellulose accessible. Step 2: Enzymes A mix of cellulase enzymes is then added to convert the cellulose and hemicellulose molecules into the simple sugars glucose and xylose. Step 3: Fermentation Yeast or bacteria are added, converting the sugar into a mixture of ethanol and water, what refineries call "the beer." Step 4: Distillation The ethanol is refined and purified, producing a fuel that could one day end up in your gas tank.
Infographic: Ryan Vulk
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