Biodiesel Glycerin (aka Glycerol or Glycerine)is a byproduct resulted in the biodiesel production process. The substance is also known as crude glycerin or impure glycerol because of its content of numerous other substances which diminish the concentration of glycerin and decrease its positive effects. Unlike pure glycerin extracted through saponification, the biodiesel glycerin is available for cosmetic, medical or weapon industrial use only after it passes through a thorough filtration process.
Crude Biodiesel Glycerin vs. Pure Glycerin
The quantity of biodiesel glycerin has increased dramatically in the last decade. While in 1999, in the United States were reported about 500,000 gallons of glycerin resulted from biodiesel production, in 2005 the quantity reached 70 million gallons according to the figures published in 2006 by the National Biodiesel Board. Therefore, the need to safely deposit and dispose of the substance is imperative. The filtration process, while relatively costly for small producers, is a safe and eco-friendly alternative to destroying or hazardous disposal.
Crude glycerol filtration is done by fractional vacuum distillation or chemical additions in order to obtain different degrees of purity. For the highly pure glycerol, further purification processes are employed. Bleaching, ion exchanging and deodoring are only some of the extra processes through which the biodiesel glycerin must pass through until reaching the correct purity and possess the benefits normally possessed by glycerin.
The high purity biodiesel glycerin is then sold to cosmetic factories, alimentary industry and weapon industry where it is used for missile production. The difference in price is significant between the refined and crude glycerin. While the crude biodiesel glycerin can be sold for even 2 cents per pound, with a maximum of 10 cents per pound, the same substance after filtration can reach $1.28 and go up to $1.65. The business can become profitable for large companies which have the necessary technology and funds to purchase and implement the specific equipment.
Biodiesel Glycerin for Cosmetic Industry
With an increased production of biodiesel, the glycerin quantity which needs to be dealt with is getting larger day by day. However, little can be done with biodiesel glycerin in the cosmetic industry until refined and transformed in 100% pure glycerin. No cosmetic product contains unrefined biodiesel glycerol for safety reasons. Furthermore, people preparing glycerin skin care products in their homes are strongly cautioned against using unrefined glycerin as it may contain vegetable and chemical residues which may cause serious side effects. When purchasing biodiesel glycerin it is recommended to double check for purity specifications.
Fermentation of Biodiesel Glycerin to obtain Ethanol
While filtration systems have advanced and the refined biodiesel glycerin reached the purity of traditionally produced glycerin, only a small portion of this byproduct is used in cosmetic, health care, alimentary and weapon industry. The costs associated with filtration have determined scientists to look for more affordable uses for this by-product. Recently two Rice University professors have discovered a more profitable way to transform biodiesel glycerin (aka Glycerol or Glycerine) into a useful compound. Using E.coli bacteria to decompose glycerin, the two scientists claim to have obtained ethanol, another highly popular biofuel. According to the same source, the costs associated with ethanol production using this procedure will cost up to 40% less than obtaining it from corn. While the quantity of biodiesel glycerol may not be enough to cover the entire need for ethanol, the alternative seems a great solution to use the large amounts of by-product resulted in the biodiesel production process.