 | |
 Sodium, Na Phosphorus, P Oxygen, O | |
 Trisodium phosphate hydrate | |
| Names | |
|---|---|
| IUPAC name Trisodium phosphate | |
Other names
| |
| Identifiers | |
| |
3D model (JSmol) | |
| ChEBI | |
| ChEMBL | |
| ChemSpider |
|
| ECHA InfoCard | 100.028.645 |
| EC Number |
|
| E number | E339(iii)(antioxidants, ...) |
| KEGG |
|
| RTECS number | |
| UNII |
|
| |
| |
| Properties | |
| Na3PO4 | |
| Molar mass | 163.939 g·mol−1 |
| Appearance | White, granular or crystalline solid |
| Density | 2.536 g/cm3 (17.5 °C, anhydrous) 1.62 g/cm3 (20 °C, dodecahydrate)[2][3][4] |
| Melting point | 1,583 °C (2,881 °F; 1,856 K) (anhydrous)[3] 73.4 °C (164.1 °F; 346.5 K) (dodecahydrate)[4] |
| Boiling point | 100 °C (212 °F; 373 K) (dodecahydrate) decomposes[4] |
| Solubility | Insoluble inethanol,carbon disulfide[4] |
| Basicity (pKb) | 2.23 |
| Structure | |
| Trigonal | |
| Thermochemistry | |
| 665 J/(mol·K) (dodecahydrate)[4] | |
Std molar entropy(S⦵298) | 224.7 J/(mol·K) (anhydrous)[3] 660 J/(mol·K) (dodecahydrate)[4] |
Std enthalpy of formation(ΔfH⦵298) | −1935.5 kJ/mol (anhydrous)[3] −5480 kJ/mol (dodecahydrate)[4] |
Gibbs free energy(ΔfG⦵) | −1819 kJ/mol (anhydrous)[3] |
| Pharmacology | |
| A06AD17 (WHO) A06AG01 (WHO)B05XA09 (WHO) | |
| Hazards[6] | |
| GHS labelling: | |
  | |
| Danger | |
| H315,H318,H335 | |
| P261,P280,P305+P351+P338 | |
| NFPA 704 (fire diamond) | |
| Flash point | Non-flammable |
| Safety data sheet (SDS) | ICSC 1178 |
| Related compounds | |
Othercations | |
Related compounds | |
Except where otherwise noted, data are given for materials in theirstandard state (at 25 °C [77 °F], 100 kPa). | |
Trisodium phosphate (TSP) is aninorganic compound with thechemical formulaNa3PO4. It is a white, granular or crystalline solid, highly soluble in water, producing analkaline solution. TSP is used as acleaning agent,builder,lubricant,food additive,stain remover, anddegreaser.[7]
As an item of commerce TSP is often partiallyhydrated and may range fromanhydrousNa3PO4 to thedodecahydrateNa3PO4·12H2O. Most often it is found in white powder form. It can also be calledtrisodium orthophosphate or simplysodium phosphate.
Trisodium phosphate is produced by neutralization ofphosphoric acid usingsodium carbonate, which producesdisodium hydrogen phosphate. The disodium hydrogen phosphate is reacted withsodium hydroxide to form trisodium phosphate and water.
Trisodium phosphate was at one time extensively used in formulations for a variety of consumer-grade soaps and detergents, and the most common use for trisodium phosphate has been in cleaning agents. ThepH of a 1% solution is 12 (i.e., verybasic), and the solution is sufficiently alkaline tosaponify grease and oils. In combination withsurfactants, TSP is an excellent agent for cleaning everything from laundry to concrete driveways. This versatility and low manufacturing price made TSP the basis for a plethora of cleaning products sold in the mid-20th century.
TSP is still sold and used as a cleaning agent. Its use has diminished in the United States and many other parts of the world because, like many phosphate-based cleaners, it is known to cause extensiveeutrophication of lakes and rivers once it enters a water system.[8]
Although it is still the active ingredient in some toilet bowl-cleaning tablets, TSP is generally not recommended for cleaning bathrooms because it can stain metal fixtures and can damagegrout.[9]
With the formula4Na3PO4·NaOCl·44H2O the material called chlorinated trisodium phosphate is used as adisinfectant andbleach, likesodium hypochlorite. It is prepared using NaOCl in place of some of thebase to neutralizephosphoric acid.[7]
In the U.S., trisodium phosphate is an approved flux for use inhard soldering joints inmedical-grade copper plumbing. The flux is applied as a concentrated water solution and dissolves copper oxides at the temperature used in copper brazing. Residues are water-soluble and can be rinsed out before plumbing is put into service.
TSP is used as an ingredient in fluxes designed to deoxygenate nonferrous metals for casting. It can be used in ceramic production to lower the flow point of glazes.
TSP is still in common use for the cleaning, degreasing, and deglossing of walls prior to painting. TSP breaks the gloss ofoil-based paints and opens the pores oflatex-based paint, providing a surface better suited for the adhesion of the subsequent layer.[10][unreliable source?]
Sodium phosphates includingmonosodium phosphate,disodium phosphate, and trisodium phosphate are approved as food additives in the EU. They are commonly used as acidity regulators and have the collectiveE numberE339.[11] The United StatesFood and Drug Administration lists sodium phosphates asgenerally recognized as safe.[12][13]
Trisodium phosphate has gained a following as a nutritional supplement that can improve certain parameters of exercise performance.[14] The basis of this belief is the fact thatphosphate is required for the energy-producingKrebs cycle central to aerobic metabolism.Phosphates are available from a number of other sources that are much milder than TSP.
In the Western world, phosphate usage has declined because of damage it causes to lakes and rivers througheutrophication.
By the end of the 20th century, many products that formerly contained TSP were manufactured with TSP substitutes, which consist mainly ofsodium carbonate along with various admixtures of nonionic surfactants and a limited percentage of sodium phosphates.
Products sold as TSP substitutes, containingsoda ash andzeolites, are promoted as direct substitutes. However, sodium carbonate is not as strongly basic as trisodium phosphate, making it less effective in demanding applications.[citation needed] Zeolites, which are clay based, are added to laundry detergents as water softening agents and are essentially non-polluting; however, zeolites do not dissolve and can deposit a fine, powdery residue in the wash tub.[citation needed] Cleaning products labeled as TSP may contain other ingredients, with perhaps less than 50% trisodium phosphate.[15]
{{cite web}}: CS1 maint: archived copy as title (link)