Glycerine

Glycerin, Glycerol, 1, 2, 3-Propanetriol, 

1,2,3-Trihydroxypropane

Structural Formula:

Physical & Chemical Properties

Appearance:

viscous colourless liquid

Stability & Reactivity

Flash Point:

177°C (Cleveland Open Cup)

l         Stable. Incompatible with perchloric acid, lead oxide, acetic anhydride, nitrobenzene, 

          chlorine, peroxides. Flammable.

l         A stable material under normal and anticipated storage and handling conditions.

l         Handling after using needs the care because of strong moisture-absorbing material.

l         Contact of glycerine with strong oxidizing agents such as chromium trioxide, potassium 

          chlorate or potassium permanganate may  cause an explosion or fire.

Toxicological Information

Mist is a respiratory irritant at high concentrations. Repeated contact may cause dehydration

of skin. Typical TLV 10 mg/m³ (nuisance).

When glycerine is heated above 150°C, it starts decomposition and produces toxic smoke called acrolein (acraldehyde, or prop-2-enal).   

Acrolein is such a severe pulmonary irritant and lacrimating agent that it has been used as a

chemical weapon during World War I.

About Glycerine

Glycerine is a colourless, transparent, and odourless sweet syrupy liquid.   The word of glycerine is from Greek, glykys, meaning sweet.

Glycerine is a neutral, colourless, sweet-tasting thick liquid with a wide range of food, 

pharmaceutical and industrial applications.  It is highly valued as a skin moisturiser in soaps and lotions, a softening agent in candy and baked goods, a substitute for Propylene Glycol in water-based hydraulic fluids, an anti-freeze component in paints, coatings and hydraulic equipment and a plasticiser in paints, plastics, cellophane etc, to name just a few of over 1,700 uses.  According to the Soap and Detergent Association, “it is virtually non-toxic and non-irritating, and has no known negative environmental effects.”

History of Glycerine

In 1779, Swedish scientist K.W. Shele discovered Glycerine in a hydrolysate of olive oil.  Initially Glycerine was used in the manufacture of glue and cork, and over the time,  applications extended to use in dye auxiliaries for textiles and ink. 

In 1867, A.B. Nobel made dynamite from Glycerine, a development that proved a major turning point in the expansion of applications for Glycerine.

Glycerine is prevalent in plants and seaweed and in animals.  In humans glycerine is accumulated subcutaneously or in muscle tissue in the form of lipids.  Substances for which fatty acids are ester-bonded to all three hydroxyl groups in the glycerine structure are known as lipids or oils and fats.

Types of Glycerine

There are two types of glycerine:  natural glycerine are derived from vegetable oils and animal fats such as soybean, corns, rapeseeds, coconuts, and synthetic glycerine is man-made and derived from petroleum.

    Sources of natural crude glycerine

     Soap making          traditional source of crude glycerine, low glycerine content sweet 

                                                        water at high impurities.

             Oleochemical        higher quality crude glycerine with lower impurity.  It is  treated

		             as a proper product and price is high.

             Biodiesel                  qualities vary widely, containing organic and inorganic impurities.

             Fermentation        very low glycerine content sweet water contains large amount of 

                                                        biological and organic impurities. 

Manufacture of Glycerine

Crude glycerine is usually first produced by refining and condensing an aqueous solution (sweet water) obtained from hydrolysis of oils and fats, then further distilling and refining the solution until arriving at the finished product.  Now, due to the development of biodiesel industry, natural glycerine is the predominate type of glycerine produced worldwide.

Despite being an ancient technology and having been used for many centuries, distillation is still the only technique used in glycerine refining industry.  Today, glycerine is  distilled under extreme vacuum which brings  glycerine's boiling point down to as low as 160 °C and has achieved reduction of production costs. However, it requires expensive equipment plus high costs to maintain extreme vacuum.

A diagram shows how distillation works

An ancient technology and still the only technique for today's glycerine refining industry

New Technology

New technology for glycerine refining is currently under development. With the new

technology, high grade glycerine can be produced at much lower costs, lower energy

consumptions, less wastes and is environmental friendly. The new technology enables the customerised glycerine products and is regarded as the future for the glycerine refining industry.

Please contact us if you would like to know more about the new glycerine refining technology.