Glycerine, Glycerin or Glycerol (C3H8O3) is an alcohol (hence the name glycerol) with three hydroxyl groups (OH):
H H H CH2-OH | | | | H---C---C---C---H or CH-OH | | | | OH OH OH CH2-OHOther synonyms of glycerine are 1,2,3-propanetriol; D-glycerol; L-glycerol; 1,2,3-Trihydroxypropane; glyceritol; glycyl alcohol; trihydroxypropane; Glycerin mist; Polyhydric alcohols; Propanetriol
Table of contents |
2 Glycerine and triglycerides 3 Glycerine and biodiesel 4 Purification 5 Applications 6 External links |
In its common liquid form, glycerol is nonpoisonous, colorless, odorless and sweet tasting and has a high viscosity.
Glycerin is soluble in water, because of the three hydrophilic hydroxyl groups (OH).
When referring to its function in living organism, the term glycerol is preferred. Glycerol is an important component of triglycerides (i.e. fats and oils) and of phospholipids. When the body uses stored fat as a source of energy, glycerol and fatty acids are released into the bloodstream. The glycerol component can be converted to glucose by the liver and provide energy for cellular metabolism.
A byproduct of saponification and transesterification to obtain biodiesel, this is produced by hydrolysis of three ester linkages and loss of three equivalents of fatty acid from fat or biological oil.
Fats and oils are insoluble in water, because the OH groups of glycerine are replaced by ester groups. They are hydrophobic (see also solubility of alcohol in water).
As a byproduct of biodiesel production, each of the OH sites in CH2-OH--CH-OH--CH2-OH is one of the three places where an ester is broken off the triglyceride molecule.
See: transesterification.
Like biodiesel by-product, the purification of the lower glycerine phase involves: neutralisation, separation of unreacted methanol, dilution with wash liquid stream coming from methylester washing, splitting of soaps and final concentration up to 80%. Partially refined glycerine can be delivered as such to specialized distillers.
Feedstock pre-treatment and upgrading of glycerine to pharmaceutical grade (>99,7%) can be optionally implemented within the biodiesel factory itself.
See also : oleochemicals.
Glycerine is also the title of a single from the album Sixteen Stone by the band Bush.Properties
Glycerine and triglycerides
Glycerine and biodiesel
Purification
Applications
Glycerine is a component of glycerine soap, which is made from denatured alcohol, glycerine, sodium castorate (from castor), sodium cocoate, sodium tallowate, sucrose, water and parfum (fragance). Sometimes one adds sodium laureth sulfate. This kind of soap is used by people with sensitive, easily irritated skin, contains no detergents. and prevents skin dryness with its moisturizing properties.
Use a mixture of one part glycerin to two parts water. Place the mixture in a flat pan, and totally submerge the leaves in a single layer in the liquid. You'll have to weight them down to keep them submerged. In two to six days, they should have absorbed the liquid and be soft and pliable. Remove them from the pan and wipe off all the liquid with a soft cloth. Done correctly, the leaves will remain soft and pliable indefinitely.External links