Tributyl phosphate
Spacefill model of Tributyl phosphate
Ball and stick model of Tributyl phosphate
Names
Preferred IUPAC name
Identifiers
ChEBI
ChemSpider
ECHA InfoCard
100.004.365
KEGG
UNII
InChI=1S/C12H27O4P/c1-4-7-10-14-17(13,15-11-8-5-2)16-12-9-6-3/h4-12H2,1-3H3
Y Key: STCOOQWBFONSKY-UHFFFAOYSA-N
Y InChI=1/C12H27O4P/c1-4-7-10-14-17(13,15-11-8-5-2)16-12-9-6-3/h4-12H2,1-3H3
Key: STCOOQWBFONSKY-UHFFFAOYAN
Properties
C 12 H 27 O 4 P
Molar mass
266.318 g·mol−1
Appearance
Colorless to pale-yellow liquid[ 1]
Density
0.9727 g/mL
Melting point
−80 °C (−112 °F; 193 K)
Boiling point
289 °C (552 °F; 562 K)
0.4 g/L[ 2]
Vapor pressure
0.004 mmHg (25°C)[ 1]
1.4231 (at 20 °C) [ 3]
Hazards
NFPA 704 (fire diamond)
Flash point
146.1 °C (295.0 °F; 419.2 K)
Lethal dose or concentration (LD, LC):
1189 mg/kg (mouse, oral) 3000 mg/kg (rat, oral)[ 4]
227 ppm (cat, 4–5 h) 123 ppm (rat, 6 h) 117 ppm (rat) 2529 ppm (rat, 1 h)[ 4]
2214 ppm (cat, 5 h)[ 4]
NIOSH (US health exposure limits):
TWA 5 mg/m3 [ 1]
TWA 0.2 ppm (2.5 mg/m3 )[ 1]
30 ppm[ 1]
Safety data sheet (SDS)
External MSDS
Except where otherwise noted, data are given for materials in their
standard state (at 25 °C [77 °F], 100 kPa).
Chemical compound
Tributyl phosphate , known commonly as TBP , is an organophosphorus compound with the chemical formula (CH3 CH2 CH2 CH2 O)3 PO. This colourless, odorless liquid finds some applications as an extractant and a plasticizer . It is an ester of phosphoric acid with n -butanol .
Production
Tributyl phosphate is manufactured by reaction of phosphoryl chloride with n -butanol .[ 5]
POCl3 + 3 C4 H9 OH → PO(OC4 H9 )3 + 3 HCl
Production is estimated at 3,000–5,000 tonnes worldwide.[ 6]
Use
TBP is a solvent and plasticizer for cellulose esters such as nitrocellulose and cellulose acetate , similarly to tricresyl phosphate . It is also used as a flame retardant for cellulose fabrics such as cotton.[ 7] [ 8] It forms stable hydrophobic complexes with some metals; these complexes are soluble in organic solvents as well as supercritical CO2 . The major uses of TBP in industry are as a component of aircraft hydraulic fluid , brake fluid , and as a solvent for extraction and purification of rare-earth metals from their ores .[ 6]
TBP finds its use as a solvent in inks , synthetic resins , gums , adhesives (namely for veneer plywood ), and herbicide and fungicide concentrates.
As it has no odour, it is used as an anti-foaming agent in detergent solutions, and in various emulsions , paints , and adhesives . It is also found as a de-foamer in ethylene glycol -borax antifreeze solutions.[citation needed ] In oil-based lubricants addition of TBP increases the oil film strength. It is used also in mercerizing liquids, where it improves their wetting properties. It can be used as a heat-exchange medium.[ 9] TBP is used in some consumer products such as herbicides and water-thinned paints and tinting bases.[ 10]
Nuclear chemistry
Tributyl phosphate is used in combination with di(2-ethylhexyl)phosphoric acid for the solvent extraction of uranium, as part of the purification of natural ores.[ 11] It is also used in nuclear reprocessing as part of the PUREX process. A 15–40% (usually about 30%) solution of tributyl phosphate in kerosene or dodecane is used in the liquid–liquid extraction (solvent extraction) of uranium , plutonium , and thorium from spent uranium nuclear fuel rods dissolved in nitric acid . Liquid extraction can also be used for chemical uranium enrichment.[ 12]
Hazards
In contact with concentrated nitric acid the TBP-kerosene solution forms hazardous and explosive red oil .
References
^ a b c d e NIOSH Pocket Guide to Chemical Hazards. "#0625" . National Institute for Occupational Safety and Health (NIOSH).
^ Velavendan, P; Sachithanantham, Ganesh; Pandey, N.K.; Geetha, R; Ahmed, M; Mudali, Kamachi; Natarajan, Rajamani (2012). "Studies on solubility of TBP in aqueous solutions of fuel reprocessing". Journal of Radioanalytical and Nuclear Chemistry . 295 (2): 1113– 1117. doi :10.1007/s10967-012-1945-1 . S2CID 95976379 .
^ Pabst, Florian; Blochowicz, Thomas (December 2022). "On the intensity of light scattered by molecular liquids - Comparison of experiment and quantum chemical calculations" . The Journal of Chemical Physics . 157 (24): 244501. Bibcode :2022JChPh.157x4501P . doi :10.1063/5.0133511 . PMID 36586992 .
^ a b c "Tributyl phosphate" . Immediately Dangerous to Life or Health Concentrations (IDLH) . National Institute for Occupational Safety and Health (NIOSH).
^ G. R. Dutton and C. R. Noller (1943). "n-Butyl phosphate" . Organic Syntheses ; Collected Volumes , vol. 2, p. 109 .
^ a b "Tributyl Phosphate | SIDS Initial Assessment Profile" (PDF) . Japan Chemical Industry Ecology-Toxicology & Information Center. Archived from the original (PDF) on 2007-10-11.
^ Alongi, Jenny; Malucelli, Giulio (2015). "Cotton flame retardancy: state of the art and future perspectives". RSC Advances . 5 (31): 24239– 24263. Bibcode :2015RSCAd...524239A . doi :10.1039/C5RA01176K .
^ Gaan, Sabyasachi; Sun, Gang (June 2007). "Effect of phosphorus flame retardants on thermo-oxidative decomposition of cotton". Polymer Degradation and Stability . 92 (6): 968– 974. doi :10.1016/j.polymdegradstab.2007.03.009 .
^ "Tributyl Phosphate Product Information" . Great Vista Chemicals. 20 January 2023.
^ "Tributyl Phosphate" . Scorecard.
^ Kumar, Jyothi Rajesh; Kim, Joon-Soo; Lee, Jin-Young; Yoon, Ho-Sung (18 February 2011). "A Brief Review on Solvent Extraction of Uranium from Acidic Solutions". Separation & Purification Reviews . 40 (2): 77– 125. doi :10.1080/15422119.2010.549760 . S2CID 95358600 .
^ Nuclear energy and nuclear weapon proliferation (1. ed.). Taylor.