Glycerin
Synonyms: 1,2,3-Propeatriol;1,2,3-Trihydroxyopropane;90 Technical glycerin;90 Technical glycerine;90technicalglycerine;Bulbold;citifluoraf2;Clyzerin, wasserfrei
CAS: 56-81-5
MF: C3H8O3
MW: 92.09
EINECS: 200-289-5
Melting point 20 °C(lit.)
Boiling point 290 °C
density 1.25 g/mL(lit.)
vapor density 3.1 (vs air)
vapor pressure <1 mm Hg ( 20 °C)
FEMA 2525
refractive index n20/D 1.474(lit.)
Fp 320 °F
storage temp. 2-8°C
solubility H2O: 5 M at 20 °C, clear, colorless
Water Solubility >500 g/L (20 oC)
Sensitive Hygroscopic
Merck 14,4484
Pure glycerol appears as colorless, odorless and sweet viscous liquid. Boiling point: 290 ° C, melting point: 17.9 ° C, the relative density: 1.2613. It can be miscible with water infinitely. It can be dissolved in 11 times ethyl acetate, about 500 times ether. It is insoluble in benzene, chloroform, carbon tetrachloride, carbon disulfide, petroleum ether and oil. Anhydrous glycerol has a strong water absorption property.
Glycerol is weakly acidic, being able to react with alkaline hydroxide. For example, it reaction with copper hydroxide can produce bright blue cupric glycerinate (can be used to identify polyols). Glycerol can react with nitric acid to generate glyceryl trinitrate, also known as nitroglycerin, being a strong explosive.
Because glycerol has water absorption property, it is often used as the moisturizing agent of cosmetics, leather, tobacco, food and textile. Glycerol also has effect on lubricating the intestine, being able to be used for enema or suppository treatment of constipation. Nitroglycerides have the effect of dilating coronary arteries and can be used to treat angina. Nitroglycerin can be used as an explosive and propellant. Glycerol can react with binary acid to generate alkyd resin, widely being used in paints and coatings.
In nature, glycerol is widely presented in the form of esters. For example, a variety of animal and vegetable oils are glycerol carboxylate with hydrolyzing grease being capable to generate fatty acids and glycerol. At present, one of the major sources of glycerol is the byproduct of the soap industry (grease is hydrolyzed under alkaline conditions). The other major source is from petroleum pyrolysis gas, propylene.