- Tributyl phosphate
Tributyl phosphate, known commonly as TBP, is an organophosphorus compound with the formula (CH3CH2CH2CH2O)3PO. This colourless, odorless liquid finds some applications as an extractant and a
plasticizer. It is an esterof orthophosphoric acidwith "n"- butanol.
Tributyl phosphate is manufactured by
esterificationof orthophosphoric acidwith butyl alcohol. A laboratory synthesis proceeds with phosphorus oxychloride: [OrgSynth | author = G. R. Dutton and C. R. Noller | title = n-Butyl phosphate | collvol = 2 | collvolpages = 109| year = 1943 | prep = CV2P0109.pdf] : POCl3 + 3 C4H9OH → PO(OC4H9)3 + 3 HClProduction is estimated at 3,000 – 5,000 tonnes worldwide. [http://www.jetoc.or.jp/HP_SIDS/pdffiles/126-73-8.pdf]
TBP is a
solventand plasticizerfor cellulose esters such as nitrocelluloseand cellulose acetate. It forms stable hydrophobiccomplexes 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 fluidand as a solvent for extraction and purification of rare earth metals from their ores. [http://www.jetoc.or.jp/HP_SIDS/pdffiles/126-73-8.pdf]
TBP finds its use as a solvent in
inks, synthetic resins, gums, adhesives (namely for veneer plywood) and herbicideand fungicideconcentrates.
As it has no odour, it finds use as
anti-foaming agentin detergentsolutions, and in various emulsions, paints, and adhesives. It is also found as a defoamer in ethylene glycol- boraxantifreze solutions.Fact|date=January 2008 In oil-based lubricants addition of TBP increases the oil film strength. It is used also in mercerizingliquids, where it improves their wettingproperties. It is also used as a heat exchangemedium. [http://www.greatvistachemicals.com/industrial_and_specialty_chemicals/tributyl_phosphate.html] TBP is used in some consumer products such as herbicides and water thinned paints and tinting bases. [http://www.scorecard.org/chemical-profiles/consumer-products.tcl?edf_substance_id=126%2d73%2d8]
A 15-40% (usually about 30%) solution of tributyl phosphate in
keroseneor dodecaneis used in the liquid-liquid extraction( solvent extraction) of uranium, plutonium, and thoriumfrom spent uranium nuclear fuelrods dissolved in nitric acid, as part of a nuclear reprocessingprocess known as PUREX.
The shipment of 20 tons of tributyl phosphate to
North Koreafrom Chinain 2002, coinciding with the resumption of activity at Yongbyon Nuclear Scientific Research Center, was seen by the United Statesand the International Atomic Energy Agencyas cause for concern; that amount was considered sufficient to extract enough material for perhaps three to five potential nuclear weapons.Fact|date=January 2008
MSDShttp://www.jtbaker.com/msds/englishhtml/t4706.htm. In contact with concentrated nitric acidthe TBP-kerosene solution forms hazardous and explosive red oil.
Wikimedia Foundation. 2010.