In industry, ethanol is usually produced by starch fermentation or direct hydration of ethylene:
1, fermentation method
Fermented sugar raw materials (such as molasses, sulfurous acid waste liquid, etc.). ) and starch raw materials (such as sweet potato, corn, sorghum, etc.). );
2, ethylene hydration method
Ethylene is directly or indirectly hydrated.
Direct hydration of ethylene is the direct reaction between ethylene and water to produce ethanol under the conditions of heating, pressure and catalyst.
Extended data
Main types
1. According to the raw materials used in production, it can be divided into starch raw material fermented alcohol, molasses raw material fermented alcohol and sulfite pulp waste liquid fermented to produce alcohol.
Starch raw materials ferment alcohol (generally, starch-containing raw materials such as potatoes, cereals and wild plants hydrolyze starch into glucose under the action of microorganisms, and then further ferment by yeast to produce alcohol);
Fermentation of alcohol by molasses (directly using sugar in molasses, diluting and sterilizing, adding some nutrients, and producing alcohol by yeast fermentation);
2. According to the production methods, it can be divided into two categories: fermentation method and synthesis method.
3. According to the product quality or nature, it can be divided into high-purity alcohol, anhydrous alcohol, ordinary alcohol and denatured alcohol.
4. According to the product series (BG384-8 1), it is divided into excellent grade, first grade, second grade, third grade and fourth grade.
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