glycerol glycerol glycerol (/ˈɡlɪsərɒl/), also called glycerine or glycerin, is a simple triol compound. it is a colorless, odorless, viscous liquid that is sweet-tasting and non-toxic. the glycerol backbone is found in lipids known as glycerides. because it has antimicrobial and antiviral properties, it is widely used in wound and burn treatments approved by the u.s. food and drug administration. conversely, it is also used as a bacterial culture medium. its presence in blood can be used as an effective marker to measure liver disease. it is also widely used as a sweetener in the food industry and as a humectant in pharmaceutical formulations. because of its three hydroxyl groups, glycerol is miscible with water and is hygroscopic in nature. glycerol ball-and-stick model of glycerol space-filling model of glycerol names preferred iupac name propane-1,2,3-triol other names glyceringlycerine1,2,3-trioxypropane1,2,3-trihydroxypropane1,2,3-propanetriol identifiers cas number 56-81-5 y 3d model (jsmol) interactive image chebi chebi:17522 y chembl chembl692 y chemspider 733 y drugbank db04077 y echa infocard 100.000.263 e number e422 (thickeners, ...) iuphar/bps 5195 kegg d00028 y pubchem cid 753 unii pdc6a3c0ox y comptox dashboard (epa) dtxsid9020663 inchi inchi=1s/c3h8o3/c4-1-3(6)2-5/h3-6h,1-2h2 ykey: pedcqbhivmgvhv-uhfffaoysa-n yinchi=1/c3h8o3/c4-1-3(6)2-5/h3-6h,1-2h2key: pedcqbhivmgvhv-uhfffaoyaf smiles occ(o)co properties chemical formula c3h8o3 molar mass 92.094 g·mol−1 appearance colorless hygroscopic liquid odor odorless density 1.261 g/cm3 melting point 17.8 °c (64.0 °f; 290.9 k) boiling point 290 °c (554 °f; 563 k) solubility in water miscible log p −2.32 vapor pressure 0.003 mmhg (0.40 pa) at 50 °c magnetic susceptibility (χ) −57.06×10−6 cm3/mol refractive index (nd) 1.4746 viscosity 1.412 pa·s (20 °c) pharmacology atc code a06ag04 (who) a06ax01 (who), qa16qa03 (who) hazards nfpa 704 (fire diamond) 0 1 0 flash point 160 °c (320 °f; 433 k) (closed cup) 176 °c (349 °f; 449 k) (open cup) niosh (us health exposure limits): pel (permissible) twa 15 mg/m3 (total) twa 5 mg/m3 (resp) rel (recommended) none established idlh (immediate danger) n.d. safety data sheet (sds) jt baker supplementary data page glycerol (data page) except where otherwise noted, data are given for materials in their standard state (at 25 °c , 100 kpa). y verify (what is yn ?) infobox references structure although achiral, glycerol is prochiral with respect to reactions of one of the two primary alcohols. thus, in substituted derivatives, the stereospecific numbering labels the molecule with a sn- prefix before the stem name of the molecule. production glycerol is generally obtained from plant and animal sources where it occurs in triglycerides, esters of glycerol with long-chain carboxylic acids. the hydrolysis, saponification, or transesterification of these triglycerides produces glycerol as well as the fatty acid derivative: triglyceride 3 naoh / h2o δ 3 × soap 3 × glycerol triglycerides can be saponified with sodium hydroxide to give glycerol and fatty sodium salt or soap. typical plant sources include soybeans or palm. animal-derived tallow is another source. approximately 950,000 tons per year are produced in the united states and europe; 350,000 tons of glycerol were produced per year in the u.s. alone from 2000 to 2004. the eu directive 2003/30/ec set a requirement that 5.75% of petroleum fuels were to be replaced with biofuel sources across all member states by 2010. it was projected in 2006 that by 2020, production would be six times more than demand, creating an excess of glycerol as a byproduct of biofuel production. glycerol from triglycerides is produced on a large scale, but the crude product is of variable quality, with a low selling price of as low as us$0.02–0.05 per kilogram in 2011. it can be purified, but the process is expensive. some glycerol is burned for energy, but its heat value is low. crude glycerol from the hydrolysis of triglycerides can be purified by treatment with activated carbon to remove organic impurities, alkali to remove unreacted glycerol esters, and ion exchange to remove salts. high purity glycerol (greater than 99.5%) is obtained by multi-step distillation; a vacuum chamber is necessary due to its high boiling point (290 °c). synthetic glycerol