Synthetic Anhydrous 99%

Ethanol

What is Synthetic Anhydrous 99%?

Ethanol (ethyl alcohol) is a colourless, flammable liquid with a characteristic odour. Ethanol can either be produced synthetically from ethylene, a feedstock which is extracted from crude oil or natural gas, or through fermentation from sugars derived from plants or other agricultural or non-agricultural products. Ethanol produced synthetically from ethylene is chemically identical to ethanol produced by fermentation. Both processes result in an ethanol-water based product. However, ethanol produced through the fermentation process contains various impurities which have to be additionally removed in order to achieve the same grades and the same purity as with synthetic ethanol. There are three main types of ethanol according to its commercial application: fuel ethanol, potable ethanol and industrial ethanol. Industrial ethanol can be both synthetic and fermentation ethanol, with the latter accounting for 60-70% of the industrial ethanol.

The remainder of industrial ethanol demand is met by synthetic ethanol, which is not used as potable or fuel ethanol. Industrial ethanol is produced in two main grades: hydrous ethanol (96% purity) and anhydrous ethanol (99% purity). Typically, hydrous ethanol contains not less than 95.1% and not more than 96.9% ethanol. Anhydrous ethanol contains not less than 99.5% ethanol, and up to 99.9%. Within the industrial ethanol category there is a range of different end uses: anhydrous ethanol is a higher quality grade and once it has been “finished”, it contains fewer impurities. It can thus be used in applications such as pharmaceuticals, cosmetics and inks. The lower “unfinished” 96% ethanol is used for applications, where the content of ethanol and/or impurities is less stringent: automotive screen wash, paints, inks, dyes and cosmetics.

In recent years, both the quality and consistency of ethanol produced from agricultural feedstock has improved leading to increased substitutability with synthetic ethanol. A number of major fermentation ethanol producers produce industrial ethanol, including anhydrous ethanol with 99% purity.

Applications and Use

Synthetic Anhydrous 99% can be used in applications such as pharmaceuticals, cosmetics and inks. The lower “unfinished” 96% ethanol is used for applications, where the content of ethanol and/or impurities is less stringent: automotive screen wash, paints, inks, dyes and cosmetics.

Additional information

HOW ITS MADE

Synthetic ethanol is manufactured through a complex three stage process that ultimately produces a single grade of ethanol (DRAA – Double Rectified Absolute Alcohol) which is 99.9 % pure. It may either be produced synthetically from ethylene, a feedstock which is extracted from crude oil or natural gas, or through fermentation from sugars derived from plants or other agricultural or non-agricultural products. Both processes result in an ethanol-water based product. However, ethanol produced through the fermentation process contains various impurities which have to be additionally removed in order to achieve the same grades and the same purity as with synthetic ethanol.

STEP ONE Choosing the Feedstock To start, the type of feedstock is chosen for milling. The most popular grains used in production of cosmetic grade (denatured) alcohol are corn kernels or wheat kernels. STEP TWO Milling Once the grain that will be the base is chosen, milling can take place. Milling is the process in which the grain is ground into a meal, a form of flour. This process deals with starches, which are long chains of sugar molecules, classified as carbohydrates. | STEP THREE Liquefaction After milling has been completed, it is time for liquefaction. During this step, ‘slurry’ is made by adding water to the milled kernels. The slurry is then heated up in order to break the long starch molecules into smaller pieces. An enzyme known as alpha-amylase is added to catalyze the process of breaking down of the starch molecules. STEP FOUR Saccharification During this step, the broken-down starch molecules are broken down further into simple sugar glucose. An enzyme is used to catalyze this reaction; the enzyme used is called glucoamylase. STEP FIVE Fermentation Next is the fermentation process, in which yeast breaks down glucose. Yeast are the single-cell microorganisms that are added to the slurry that get their energy from the glucose. The resulting final product of this reaction is ethanol. STEP SIX Distillation and Dehydration The result of fermentation is ethanol with about a 10 to 15% ethanol concentration. This is then concentrated to become 100% ethanol through the process of distillation. During this process, ethanol is heated to its boiling point, which is lower than waters, to evaporate and then condense it. The resulting product of distillation is 95% ethanol and 5% water. Following distillation is the dehydration process, where the mixture is strained to produce pure ethanol.