Production of Ethanol
Alcohols are organic compounds with functional groups as hydroxyl (-OH). Many alcohols like methanol, ethanol and butand are produced on large scale by fermentator. Industrially ethanol is produced by fermentation of different types of yeast, other fungi and even bacteria. The types of yeast used for the production of ethanol through fermentation are;
- Saccharomyces Cerevisiae,
- Saccharomyces Carlsbergensis and
- Saccharomyces Uvarum.
The bacterium used for the production of ethanol through fermentation is Zymomonas Mobilis.
The most commonly used microbe in industrial ethanol fermentation is Saccharomyces Cerevisiae. Three types of substances that are commonly used in ethanol production are;
- Sugarcane Juice/ Molasses,
- Corn/ Maize/ Potato / Wheat Starch,
- Cellulose of Wood/ wood pulp / Algae.
The first two types of materials are most widely used for ethanol production.
Production of Ethanol by Fermentation
Ethanol is produced by continuous fermentation. Hence huge fermentors are used for manufacturing ethanol. The fermentation conditions are almost similar (PH-5, Temperature – 35 °C), throughout the world, but the culture and culture conditions are different. It is normally carried for several days but within 12 hours the production starts.
Ethanol can be recovered up to 95% by primary distillation. To obtain 100% ethanol, successive distillation with addition of Benzene has to be carried out.
Ethanol is colorless, transparent, non-toxic liquid. It is used as an important reagent in industries, laboratories and science departments of colleges and universities. It also finds its uses in pharmaceutical industries especially in preparation of different syrups.
Distilleries make ethanol based alcoholic beverages in the form of both fermented (Beer, wine) and distilled (Whisky, brandy, rum) beverages. Ethanol obtained from starch can be used as a fuel. Ethanol is also used as sterilizing agent.