Χρήστης:Dead3y3/πρόχειρο

Να μη συγχέεται με Sodium triphosphate.

Dead3y3/πρόχειρο

Εκτός αν σημειώνεται διαφορετικά, τα δεδομένα αφορούν υλικά υπό κανονικές συνθήκες (25°C, 100 kPa).
Infobox references

Το φωσφορικό τρινάτριο (TSP) είναι μια ανόργανη ένωση με χημικό τύπο Na₃PO₄. Είναι ένα λευκό, κοκκώδες ή κρυσταλλικό στερεό, ευκολοδιάλυτο σε νερό όπου και παράγει ένα αλκαλούχο διάλυμα. Τα TSP χρησιμοποιούνται ως καθαριστικά, λιπαντικά, πρόσθετα τροφίμων, αφαιρετικά λεκέδων και απολιμαντές.

Το αντικείμενο του εμπορίου είναι συνήθως μερικώς ενυδατωμένο και μπορεί να ποικίλει από άνυδρο Na₃PO₄ μέχρι το δωδεκαένδρο Na₃PO₄·12 H₂O. Πιο συχνά βρίσκεται σε μορφή άσπρης σκόνης, μπορεί επίσης να καλείται ορθοφωσφορικό τρινάτριο ή απλώς φωσφορικό νάτριο.

Παραγωγή

Το φωσφορικό τρινάτριο παράγεται από την εξουδετέρωση του φωσφορικού οξέος με την χρήση υδροξειδίων του νατρίου, συχνά με ανθρακικό νάτριο. Το ανθρακικό μπορεί να παράγει μόνο φωσφορικό δινάτριο:

Na₂CO₃ + H₃PO₄ → Na₂HPO₄ + CO₂ + H₂O

Na₂HPO₄ + NaOH → Na₃PO₄ + H₂O

Χρήσεις

Καθαρισμός

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. The pH of a 1% solution is 12 (i.e., very basic), and the solution is sufficiently alkaline to saponify grease and oils. In combination with surfactants, 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 but since the late 1960s 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 extensive eutrophication of lakes and rivers once it enters a water system. Substitutes are generally not as effective.

TSP is commonly used after cleaning a surface with mineral spirits in order to remove hydrocarbon residues and may be used with household chlorine bleach in the same solution without hazardous reactions. This mixture is particularly effective for removing mildew, but is less effective at removing mold.

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 damage grout.

Χλωριωμένο φωσφορικό τρινάτριο

Με χημικό τύπο Na₃PO4^.¼ NaOCl^.11 H₂O, το υλικό καλούμενο χλωριωμένο φωσφορικό τρινάτριο χρησιμοποιείται ως απολυμαντικό και λευκαντικό, παρόμοιο του υποχλωριώδους νατρίου. Παρασκευάζεται χρησιμοποιώντας NaOCl στη θέση ορισμένης ποσότητας βάσης, ώστε να εξουδετερωθεί το φωσφορικό οξύ.

Flux

In the U.S., trisodium phosphate is an approved flux for use in hard soldering joints in medical 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.

Painting enhancement

TSP is still in common use for the cleaning, degreasing and deglossing of walls prior to painting. TSP breaks the gloss of oil based paints and opens the pores of latex based paint providing a surface better suited for the adhesion of the subsequent layer.

Food additive

Sodium phosphates (monosodium phosphate, disodium phosphate, and trisodium phosphate) are approved as a food additive in the EU; used as antioxidant agent, E339.

Exercise performance enhancement

Trisodium phosphate has gained a following as a nutritional supplement that can improve certain parameters of exercise performance. The basis of this belief is the fact that phosphate is required for the energy-producing Krebs cycle central to aerobic metabolism. Phosphates are available from a number of other sources that are much milder than TSP. While TSP is not toxic per se, it is severely irritating to gastric mucosa unless used as part of a buffered solution.

Regulation

In the western world, phosphate usage has declined owing to ecological problems with the damage to lakes and rivers through eutrophication.

TSP Substitutes

Δείτε επίσης: Cleaning products and the environment

By the end of the 20th century, many products that formerly contained TSP were manufactured with TSP substitutes, which consist mainly of sodium carbonate along with various admixtures of nonionic surfactants and a limited percentage of sodium phosphates.

Products sold as TSP substitute, containing soda ash and zeolites, are promoted as a direct substitute. However, sodium carbonate is not as strongly basic as trisodium phosphate, making it less effective in demanding applications. Zeolites are added to laundry detergents as bulking agents that rapidly break down in water and are essentially nonpolluting. Cleaning products labeled as TSP may contain other ingredients, with perhaps less than 50% trisodium phosphate.

See also

• Sodium phosphates

External links

• Safety data from IPCS INCHEM
• International Chemical Safety Card 1178

{{Laxatives}} {{Use dmy dates|date=March 2011}}

Category:Cleaning product components Category:Food additives Category:Phosphates Category:Sodium compounds Category:Photographic chemicals