Truth about Ethanol

Fermentation using bacteria

Yeast is very good at converting glucose, and other six-carbon sugars into ethanol. Unfortunately, a significant proportion of waste biomass consists of complex natural polymers made from sugars that are not "digested" readily by yeast enzymes.

These include hemicellulose, which on hydrolysis produces a range of sugars including: mannose, xylose, arabinose and galactose, depending on the original source.

KO11

A genetically modified bacterium, developed by the microbiologist Lonnie Ingram in 1987, has enabled these sugars to be converted to ethanol. The bacterium, referred to as KO11, would normally produce acids, but the modification means ethanol is produced instead.



 The advantage over yeast is that a wider range of sugars can be processed, enabling the utilisation of biomass waste such as wood waste, corn stalks, rice hulls, and other organic waste, which would otherwise require disposal by some other method, or which could only be partially utilised by conventional fermentation methods, making them uneconomic.

 

 

Commercial Development
The BC International Corporation is attempting to develop this approach commercially in the United States, focusing on:

• areas where legislation prohibits burning of agricultural waste
• conventional ethanol plants suitable for conversion and refurbishment

 

Ethanol itself is also used:

• As a solvent in manufacture of perfumes, cosmetics, pharmaceuticals, varnishes, detergents, inks and coatings
• As a motor fuel and motor fuel blending agent (link to fuel section - when written)
• Ethanol is an intermediate in the manufacture of many products.

Ethanol is also present in many common beverages. Synthetic alcohol is not normally used for this purpose as it may contain traces of other by-products of manufacture.