SODIUM TRIPOLYPHOSPHATE

SODIUM TRIPOLYPHOSPHATE

Sodium triphosphate (STP), also sodium tripolyphosphate (STPP), or tripolyphosphate (TPP)) is an inorganic compound with formula Na5P3O10. Sodium Tripolyphosphate is the sodium salt of the polyphosphate penta-anion, which is the conjugate base of triphosphoric acid. Sodium Tripolyphosphate is produced on a large scale as a component of many domestic and industrial products, especially detergents. Environmental problems associated with eutrophication are attributed to its widespread use.

CAS No.: 7758-29-4

Synonyms:
Pentasodium triphosphate; sodium tripolyphosphate; polygon; STPP; STP; TPP; Sodium tripolyphosphate; 7758-29-4; Pentasodium triphosphate; Sodium triphosphate; STPP; Thermphos; Armofos; sodyum tripolifosfat; sodiyum tripolifosfat; sodyum tripolifosfate; sodıum trıpolıphosfate; Polygon; Tripoly; PENTASODIUM TRIPOLYPHOSPHATE; Rhodiaphos LV; Thermphos N; Empiphos stp-D; Thermphos SPR; Triphosphoric acid, pentasodium salt; Thermphos L 50; Caswell No. 799; Poly; Natriumtripolyphosphat [German]; Sodium phosphate (Na5P3O10); Sodium tripolyphosphate, anhydrous; Sodium triphosphate (Na5P3O10); Sodium tripolyphosphate (Na5P3O10); EPA Pesticide Chemical Code 076404; Na5P3O10; S 400; Triphosphoric acid, sodium salt (1:5); pentasodium;[oxido(phosphonatooxy)phosphoryl] phosphate; Sodium tripolyphosphate, for analysis; STMP; Trisodium trimetaphosphate; Sodium cyclotriphosphate; Trisodium trimetaphosphate; SODIUM TRIMETAPHOSPHATE; Trisodium trimetaphosphate; Trisodium metaphosphate; Cyclic sodium trimetaphosphate; Sodium phosphate ((NaPO3)3); Sodium trimetaphosphate [USAN]; HSDB 5048; Metaphosphoric acid, trisodium salt; Sodium metaphosphate (Na3(P3O9)); EINECS 232-088-3; Trisodium trimetaphosphate (Na3P3O9); Cyclisches trinatriummetaphosphat [German]; Metaphosphoric acid (H3P3O9), trisodium salt; Trimetaphosphoric acid (H3P3O9), trisodium salt; 1,3,5,2,4,6-Trioxatriphosphorinane, 2,4,6-trihydroxy-, trisodium salt; Cyclicsodiumtrimetaphosphate; Metaphosphoric acid (H3P3O9), sodium salt (1:3); Sodium trimetaphosphate (USAN); Polyrinsan 58; Sodiumtrimetaphosphate; Cyclisches trinatriummetaphosphat; Sodium Tripolyphosphate; trimetaphosphate grade iii trisodium; (Triphosphoric acid alpha,beta,gamma-trisodium)alpha,gamma-anhydride salt; 2,4,6-Tris(sodiooxy)-1,3,5,2,4,6-trioxatriphosphorinane 2,4,6-trioxide; Sodium metaphosphate; Maddrell's salt; Kurrol's salt; Sporix; Metaphosphoric acid, sodium salt; Sodium Kurrol's salt; Metaphosphoric acid (HPO3), sodium salt; Poly(sodium metaphosphate); Sodium phosphate (NaPO3); 10361-03-2; Polymeric sodium metaphosphate; Sodium metaphosphate (NaPO3); Insoluble metaphosphate; Insoluble sodium metaphosphate; Sodium metaphosphate, insoluble; SODIUM TRIPOLYPHOSPHATE; Metaphosphoric acid (HPO3), sodium salt, homopolymer; 14550-21-1; sodium phosphenate; Metaphosphoric acid (HPO3), sodium salt (1:1); trisodium metaphosphate; cyclic sodium trimetaphosphate; Sodium phosphate, dibasic (anhydrous); Sodium orthophosphate, secondary; Sodium acid phosphate, anhydrous; DSP; Hydrogen disodium phosphate; Phosphoric acid, sodium salt (1:2); EPA Pesticide Chemical Code 076403; Sodium monohydrogen phosphate (2:1:1); Disodium hydrogen orthophosphate; CHEBI:34683; Sodium Phosphate dibasic anhydrous; di-Sodium hydrogen phosphate anhydrous, USP grade; Monohydrogen Sodium Phosphate; Fleet enema; Potassium Phosphate Monobasic/Sodium Phosphate Dibasic; Sodium phosphate, dibasic, 98%, extra pure, anhydrous; Sodium Tripolyphosphate; Disodiumhydrogenorthophosphate; Sodium phosphate, dibasic, 99+%, for analysis, anhydrous; Sodium phosphate, dibasic, 99+%, ACS reagent, suitable for buffer solutions; Disodiumhydrogenphosphate; ACMC-20al4j; HNa2O4P; sodium hydrogen-phosphate; disodium hydrogen-phosphate; Buffer Salt, pH 6.87; Buffer Salt, pH 7.42; EC 231-448-7; Sorensen's sodium phosphate; di-sodium hydrogen phosphate; phosphoric acid disodium salt; sodium hydrogen orthophosphate; KSC377C3J; Disodium hydrogen monophosphate Natriumtripolyphosphat; Sodium tripolyphosphate, 85%, pure, tech.; Pentasodium tripolyphosphate Anhydrous; STPP; Sodium triphosphate pentabasic; Sodium triphosphate; Sodium tripolyphosphate pentabasic

Sodium Tripolyphosphate

Properties
Chemical formula Na5P3O10
Molar mass 367.864 g/mol
Appearance white powder
Density 2.52 g/cm3
Melting point 622 °C (1,152 °F; 895 K)
Solubility in water 14.5 g/100 mL (25 °C)

Preparation and properties of Sodium tripolyphosphate
Sodium tripolyphosphate is produced by heating a stoichiometric mixture of disodium phosphate, Na2HPO4, and monosodium phosphate, NaH2PO4, under carefully controlled conditions.

2 Na2HPO4 + NaH2PO4 → Na5P3O10 + 2 H2O
In this way, approximately 2 million tons are produced annually.

Sodium tripolyphosphate (STPP) is a colourless salt, which exists both in anhydrous form and as the hexahydrate. The anion can be described as the pentanionic chain [O3POP(O)2OPO3]5−. Many related di-, tri-, and polyphosphates are known including the cyclic triphosphate P3O93−. Sodium tripolyphosphate binds strongly to metal cations as both a bidentate and tridentate chelating agent.

Uses of Sodium tripolyphosphate (STTP)
In detergents
The majority of Sodium tripolyphosphate is consumed as a component of commercial detergents. Sodium tripolyphosphate serves as a "builder," industrial jargon for a water softener. In hard water (water that contains high concentrations of Mg2+ and Ca2+), detergents are deactivated. Being a highly charged chelating agent, TPP5− binds to dications tightly and prevents them from interfering with the sulfonate detergent.

Food applications of Sodium tripolyphosphate (STTP)
STPP is a preservative for seafood, meats, poultry, and animal feeds. Sodium tripolyphosphate is common in food production as E number E451. In foods, STPP is used as an emulsifier and to retain moisture. Many governments regulate the quantities allowed in foods, as it can substantially increase the sale weight of seafood in particular. The United States Food and Drug Administration lists STPP as "generally recognized as safe."

Other uses of Sodium tripolyphosphate (STTP)
Other uses (hundreds of thousands of tons/year) include ceramics (decrease the viscosity of glazes up to a certain limit), leather tanning (as masking agent and synthetic tanning agent - SYNTAN), anticaking agents, setting retarders, flame retardants, paper, anticorrosion pigments, textiles, rubber manufacture, fermentation, antifreeze." TPP is used as a polyanion crosslinker in polysaccharide based drug delivery. Toothpaste.

Health effects of Sodium tripolyphosphate (STTP)
High serum phosphate concentration has been identified as a predictor of cardiovascular events and mortality. Whilst phosphate is present in the body and food in organic forms, inorganic forms of phosphate such as sodium triphosphate are readily adsorbed and can result in elevated phosphate levels in serum. Salts of polyphosphate anions are moderately irritating to skin and mucous membranes because they are mildly alkaline.

Environmental effects of Sodium tripolyphosphate (STTP)
Because it is very water-soluble, Sodium tripolyphosphate is not significantly removed by waste water treatment. Sodium tripolyphosphate hydrolyses to phosphate, which is be assimilated into the natural phosphorus cycle. Detergents containing phosphorus contribute to the eutrophication of many fresh waters.

With prolonged heating of sodium tripolyphosphate soln, it tends to revert to the orthophosphate.

Residues of sodium tripolyphosphate are exempted from the requirement of a tolerance when used as a buffer, surfactant, suspending agent, dispersing agent, anticaking agent or conditioning agent in accordance with good agricultural practices as inert (or occasionally active) ingredients in pesticide formulations applied to growing crops or to raw agricultural commodities after harvest.

As the federal pesticide law FIFRA directs, EPA is conducting a comprehensive review of older pesticides to consider their health and environmental effects and make decisions about their future use. Under this pesticide reregistration program, EPA examines health and safety data for pesticide active ingredients initially registered before November 1, 1984, and determines whether they are eligible for reregistration. In addition, all pesticides must meet the new safety standard of the Food Quality Protection Act of 1996. Pesticides for which EPA had not issued Registration Standards prior to the effective date of FIFRA, as amended in 1988, were divided into three lists based upon their potential for human exposure and other factors, with List B containing pesticides of greater concern and List D pesticides of less concern. Sodium tripolyphosphate is found on List D. Case No: 4053; Pesticide type: fungicide, herbicide, and antimicrobial; Case Status: None of the active ingredients in the case are being supported for reregistration by their registrants. All are unsupported, or some are unsupported and some are cancelled. Cases described as "unsupported" generally are being processed for cancellation.; Active ingredient (AI): sodium tripolyphosphate; AI Status: The active ingredient is no longer contained in any registered pesticide products ... "cancelled."

Uses of Sodium tripolyphosphate (STPP)
Sodium tripolyphosphate used as a multiple purpose food substance in food for human consumption is generally recognized as safe when used in accordance with good manufacturing practice.

Sodium tripolyphosphate used as a sequestrant in food for human consumption is generally recognized as safe when used in accordance with good manufacturing practice.

Sodium tripolyphosphate used as a general purpose food additive in animal drugs, feeds, and related products is generally recognized as safe when used in accordance with good manufacturing or feeding practice.

Sodium tripolyphosphate is a food additive permitted for direct addition to food for human consumption, as long as 1) the quantity of the substance added to food does not exceed the amount reasonably required to accomplish its intended physical, nutritive, or other technical effect in food, and 2) any substance intended for use in or on food is of appropriate food grade and is prepared and handled as a food ingredient.

Interactions of Sodium tripolyphosphate (STPP)
The mechanism by which sodium tripolyphosphate increases cadmium toxicity after sc administration was investigated in mice after a dose of cadmium (30 umol/kg), alone or with sodium tripolyphosphate (90 umol/kg). ... Histological ... changes in the liver were not observed during the first 12 hr after injection of cadmium, but already 6-8 hr after injection of cadmium plus sodium tripolyphosphate early centrilobular necroses and blood stasis appeared. At 12 hr more advanced necroses were present. Sodium tripolyphosphate administered alone was nontoxic and did not change the liver morphology, when compared to animals killed immediately after injection. During the first 12 hr after cadmium administration with sodium tripolyphosphate, there was a much faster transport of cadmium, giving rise to higher liver and kidney concn of cadmium and partial inhibition of cadmium-metallothionein binding, as compared with animals receiving the same dose of cadmium without sodium tripolyphosphate.

IDENTIFICATION AND USE of Sodium tripolyphosphate (STPP): 
Pentasodium tripolyphosphate is a white powder which is soluble in water. Sodium tripolyphosphate is used as a hydrogen peroxide stabilizer. This chemical is one of the most widely used and most effective builder in heavy duty fabric washing compositions. Because of its high sequestration power, it also finds extensive application in automatic dish washing detergents. Sodium tripolyphosphate forms stable hydrates and aids in the manufacture of crisp spray dried laundry powders. It is used in dairy substitute products: milk based pudding, whipped topping, sour cream, and cheese. It is used in water softening and as a peptizing agent; emulsifier and dispersing agent, it is an ingredient of cleansers in drilling fluids to control mud viscosity in oil fields; as preservative, sequestrant, and as a texturizer in foods. The active ingredient is no longer contained in any registered pesticide products used in the United States. 

HUMAN EXPOSURE AND TOXICITY: If Sodium tripolyphosphate ingested in large amounts this chemical can cause nausea, vomiting, and diarrhea. Sodium tripolyphosphate has produced vesiculation when applied to intact and abraded skin of humans. Sodium and potassium hexametaphosphates, polyphosphates, tripolyphosphates, pyrophosphates, and other phosphates used as water softeners form complexes with calcium and, after ingestion, are capable of seriously reducing the serum level of ionic calcium. They have less corrosive effect on mucous membranes than sodium or potassium hydroxide. Eye contact with concentrated material can cause conjunctival edema and corneal destruction. Chronic dermatitis may follow repeated contact of the chemical that migrates to food from packaging materials. Occupational exposure involves acetyl cellulose makers, bronze alloy makers, munitions workers, smoke bomb and incendiary makers, pesticide rat poison worker, fertilizer makers, electroluminescent-coating makers, and semiconductor workers. ANIMAL STUDIES: Sodium tripolyphosphate induced emesis in dogs. Dietary administration in animals has caused decrease iron content in bone, liver, and spleen, and bone depletion of calcium.

Gastrointestinal absorption, transport, tissue deposition, and excretion of cadmium were investigated in mice after single or repeated exposure with or without chelating agents. Male CBA-mice received a single oral 69 mg/kg dose of cadmium-109 in combination with a single 600 mg/kg dose of nitrilotriacetic acid, sodium tripolyphosphate, or 60 or 600 mg/kg ethylenediaminetetraacetic acid. Animals were observed, and blood cadmium concentrations followed, from 5 minutes to 21 days before dissection and tissue analysis. Female CBA-mice received a single oral 15 ug/kg dose of radioactive cadmium in combination with cadmium and 50 or 500 ppm of these chelating agents in their drinking water and were observed for 18 months. Acute cadmium toxicity was reduced in mice given cadmium in combination with ethylenediaminetetraacetic acid. At all times from 5 minutes to 5 hours after dosing blood cadmium concentrations were lowest in mice exposed to cadmium plus sodium tripolyphosphate. Almost all cadmium in kidneys of mice exposed to cadmium and ethylenediaminetetraacetic acid at the higher doses was bound in the cadmium ethylenediaminetetraacetic acid complex, while at the lower dose of ethylenediaminetetraacetic acid part of the cadmium was bound to high molecular weight proteins. Cadmium 24 hour elimination was increased from 20% with cadmium alone to 45% with the higher and 35% with the lower dose of ethylenediaminetetraacetic acid. Whole body retention at 21 days was 4.4% with cadmium alone, 2% with nitrilotriacetic acid and 5.5% with sodium tripolyphosphate. With repeated exposure no substantial differences in whole body or organ retention of cadmium were seen after treatment with different chelating agents. Chelating agents did not affect mortality over 18 months. /It was concluded/ that the effects of different chelating agents on acute cadmium toxicity and metabolism are produced by change in the stability of the chelate complexes and the availability of metal binding ligands in-vivo.

Warnings of sodium tripolyphosphate in fish
You might be paying more for seafood that contains this chemical, because it can increase the weight of the products to which it’s applied.

Worse, you might not even know it’s there, because labelling of this potentially toxic chemical is not mandatory in the US, says Ms Logan.

So what is sodium tripolyphosphate? It’s an additive—called sodium tripolyphosphate, or STPP for short—and it is used to make your seafood appear firmer, smoother and glossier. Seafood manufacturers may soak your seafood in a quick chemical bath of STPP in order to achieve these effects.

Some of the more commonly “soaked” seafood items include scallops, shrimp and anything filleted that’s very flaky—like hake, sole or imitation crab meat, Ms Logan continues.

If seafood is soaked for too long in an STPP bath, it may absorb more water, which means you’ll pay more for the product by the pound because the excess water makes it weigh more. A product may have been “soaked” with sodium tripolyphosphate if a milky white liquid oozes from the fish as you cook it, and it may also deflate in size a bit.

In large quantities, sodium tripolyphosphate is a suspected neurotoxin, as well as a registered pesticide and known air contaminant in the state of California.

How can one steer clear of STPP? Ask at your market or fish shop if the scallops or shrimp you’re being sold are “dry.” You can ask the same thing of waiters at seafood restaurants—they should have an understanding of the topic. (In industry-speak, “wet” fish means a product has been soaked in phosphates.) You can also check labels of packaged products, which may list sodium tripolyphosphate as an ingredient. Unfortunately, it’s not mandatory for companies and sellers to do so, concludes Ms Logan.

Sodium Tripolyphosphate
Na₅P₃O₁₀
Sodium tripolyphosphate (STPP) — is widely used as a component for the production of synthetic detergents, water treatment, as well as in the ceramic, paint, varnish and other industries. We produce 15 technical Sodium Tripolyphosphate grades of powder and granular type.

When producing synthetic detergents, STPP is usually added to the pulp.

STPP with a high rate of hydration is preferable to use on modern equipment due to a shorter period of reaction with water, which is required for powerful high-speed mixers. On other equipment, it is recommended to use STPP with medium and/or low rate of hydration, which avoids the formation of lumps in the detergent slurry.

What Is the Usage of Sodium Tripolyphosphate?
Sodium tripolyphosphate, also known as pentasodium triphosphate, pentasodium tripolyphosphate or sodium triphosphate, is used in a wide range of applications in the manufacture of cleaning products and food preservatives as well as in water treatment facilities.

Manufacture of Sodium tripolyphosphate (STPP)
Sodium tripolyphosphate is a sodium salt of triphosphoric acid. Sodium tripolyphosphate is manufactured in chemical laboratories by mixing disodium phosphate and monosodium phosphate.

A Powerful Cleaning Agent
Sodium tripolyphosphate is used in a variety of cleaning products. It improves the ability of various ingredients in the detergent to penetrate the fibers of clothes (as well as other surfaces and materials to be cleaned) more deeply, and aids in foaming and bubbling. Therefore, most chemical plants that make sodium tripolyphosphate list "detergents" as the primary area of use for this chemical.

Food Additive
Sodium tripolyphosphate also gives a fresh appearance to meat and seafood while slowing down spoilage. The chemical helps to preserve the natural color of meat and fish and improves their texture. This is done by improving the water-holding capacity of animal products and consequently slowing down their drying

Tanning Agent for Leather
Sodium tripolyphosphate is listed as a tanning agent for leather. Interestingly, the chemical is also used as an oil contamination resistance agent in paper production. So, Sodium tripolyphosphate can both help manufacturers apply the right color to a medium as well as keep unwanted color away.

Other Uses of Sodium tripolyphosphate (STPP)
Other uses of sodium tripolyphosphate include petroleum refining, metallurgy, mine applications and water treatment. The last application is made possible by its pH buffering ability, meaning that it can "soften" acidic water by neutralizing its acidity. This quality is one of the reasons it is added to detergents.

Description
Sodium tripolyphosphate (STPP) is an alkaline salt that will raise the pH of meats and seafood, enough to increase their water-holding capacity. 

Alternative Names
STP, STPP

Culinary Uses of Sodium tripolyphosphate
Sodium tripolyphosphate is used as a preservative for poultry, meat, and seafood. Sodium tripolyphosphate is also added, along with other sodium polyphosphates, to processed cheeses as an emulsifier. The polyphosphates are negatively charged chains of phosphorus and oxygen that attract water molecules. When added to the cheese, they remove calcium from casein matrix and also bind themselves to the casein while bringing moisture with them. The effect is that the polyphosphates loosen the protein matrix helping keep the mixture emulsified and ensure even melting. This applies to other uses such as force-meats: Sodium tripolyphosphate will help prevent the poultry, fish, or meat from becoming greasy and falling apart during heating.

Preparation Tips of Sodium tripolyphosphate
Careful not to add too much Sodium tripolyphosphate, as many find its taste very harsh in high quantities.

Sodium tripolyphosphate Chemical Properties,Uses,Production

detergent builders
Sodium tripolyphosphate is a kind of excellent detergent additives, the largest amount of detergent in the production process is set, its role has four aspects:

1. the effect of heavy metal ion chelate: heavy metal ions in the process of washing water, can combine detergent molecules to form insoluble metal salt,reduce the washing ability, even complete loss of function. Therefore, it is necessary to add chelating agent, which can make water containing heavy metal ions into harmless substancesin the detergent. Sodium tripolyphosphate has strong chelation for heavy metal ions, sealing them and eliminating the adverse effects on the washing. In addition, it can capture dirt contained various metals in washing process, playing the role of dissociation of dirt, used as soap synergist and preventing bar soap grease precipitation and bloom.

2. The dirt on his gum, emulsifying and dispersing effect: Dirt often contain body fluids (mainly protein and fat like substances), also contains the sand from the outside world, dust etc.. Sodium tripolyphosphate has the expansion, solubilization on dirt protein, and the effect of the glue solution; emulsification of fat promotes; has dispersing effect on solid dirt, strong emulsification of lubricating oil and fat, can be used to adjust the pH value of buffer liquid soap.

3. prevent caking of detergent: Synthetic detergent powder is hygroscopic, such as stored in high humidity areas, it is necessary to caking phenomenon. Using detergent agglomerates is inconvenient. While the water absorption of sodium tripolyphosphate formed the hexahydrate, with characteristics of dry. When there is extensive use of detergent formulations, it can serve to prevent caking phenomenon caused by moisture absorption, keeping dry granular of the synthetic detergent.

4. It has a larger buffer alkaline washing solution, pH value is maintained at about 9.4, which is conducive to the removal of acidic dirt.

Chemical Properties of Sodium tripolyphosphate (STPP)

Sodium tripolyphosphate (STPP) is a white powder, soluble in water, its water solution is alkaline. It is a crystalline inorganic salt that can exist in two anhydrous crystalline forms (phase I and phase II) or a hydrous form (Na5P3O10 . 6H2O). STPP is used in a large variety of household cleaning products, mainly as a builder, but also in human foodstuffs, animal feeds, industrial cleaning processes and ceramics manufacture.

Uses of Sodium tripolyphosphate (STPP)

1. Sodium tripolyphosphate is used for meat processing, synthetic detergent formulations, textile dyeing, also used as dispersing agent, solvent etc.
2. It is used as soft water, also used in confectionery industry.
3. It is used as power stations, locomotive vehicle, boiler and a fertilizer plant cooling water treatment, water softener. It has strong ability to Ca2+ collaterals, per 100g to complex 19.5g calcium , and because SHMP chelation and adsorption dispersion destroyed the normal process of calcium phosphate crystal growth, it prevents the formation of calcium phosphate scale. Dosage is 0.5 mg/L, prevent that scaling rate is up to 95%~100%.
4. Modifier; emulsifier; buffer; chelating agent; stabilizer. Mainly for canned ham tenderization; canned broad beans in the Yuba softening. Can also be used as soft water, pH regulator and thickening agent.
5. It is used for synergist for soap and preventing bar soap grease precipitation and bloom. It has strong emulsification of lubricating oil and fat. It can be used for adjusting the value of pH of buffer liquid soap. Industrial water softener. Pre tanning agent. Dyeing auxiliaries. Paint, kaolin, magnesium oxide, calcium carbonate, such as industrial in the preparation of suspensions of dispersant. Drilling mud dispersant. In paper industry used as anti oil agents.
6. Sodium tripolyphosphate is used for detergents. As additives, synergist for soap and preventing bar soap crystallization and bloom, industrial water soft water, pre tanning agent, dyeing auxiliaries, well digging mud control agent, paper with oil on preventing agent, paint, kaolin, magnesium oxide, calcium carbonate, such as hanging floating fluid treatment effective dispersant. Food grade sodium tripolyphosphate as a variety of meat products, food improver, the clarification of the beverage additives.
7. Quality improver to improve food complexed metal ions, pH value, increasing ionic strength, thereby improving food focus and water holding capacity. Provision of China can be used for dairy products, fish products, poultry products, ice cream and instant noodles, maximum dose is 5.0g/kg; in canned, maximum use juice (taste) beverages and vegetable protein beverage is 1.0g/kg.

Methods of production of Sodium tripolyphosphate (STPP)

1. recrystallization
The industrial sodium tripolyphosphate dissolved in 60~70℃, water solution prepared from 17% to 22%, and filtered to remove the insoluble impurities; and then concentrated by vacuum, cooling crystallization, separation, drying to obtain the product.
Hot phosphoric acid in two steps
In neutralization tank with the consumption of soda ash and food grade phosphoric acid with 50%~60% solution, neutralizing liquid into the intermediate storage tank, pump sent to the spray drying tower for spray drying; powder sent to rotary polymerization furnace, heating to 540~580 ℃ and dehydration polymerization, in air cooling collapse into powder. In aqueous solution of anhydrous ethanol, precipitates six water.
5Na2CO3 +6H3PO4→4Na2HPO4 +2NaH2PO4 +5CO2+5H2O
4Na2HPO4 +2NaH2PO4→2Na5P3O10 +4H2O

2. Two-step thermal process of phosphoric acid will place(55%~60%) phosphate solution via measuring the neutralization tank, heating and the agitator is started under stirring slowly, adding soda ash for neutralization reaction, neutralization tank to maintain 2 molecular hydrogen phosphate disodium on 1 molecular sodium dihydrogen phosphate ratio. The mixed liquid and the high groove into the spray, drying tower, drying and after drying of orthophosphate dry from the tower bottom discharge sent to rotary polymerization furnace, carried away by a gas stove a few dry by the cyclone dust collector to be recycled.

Dry phosphate Is in the furnace and at temperature of 350 to 450℃ polymerization reaction generated sodium tripolyphosphate, after cooling, crushing of refined sodium tripolyphosphate.
5Na2CO3 +6H3PO4→4Na2HPO4 +2NaH2PO4 +5CO2+5H2O
4Na2HPO4 +2NaH2PO4→2Na5P3O10 +4H2O
Wet process phosphoric acid one step will rock phosphate and sulfate reaction of phosphoric acid and soda ash used in removing fluoride can remove the fluosilicic acid, in the desulfurization tank with barium carbonate to remove sulfate, in order to reduce the sodium sulfate content in phosphoric acid.

Then using sodium carbonate for neutralization. After filtration to a large number of iron, aluminum and other impurities. The fine tuning, filtering, income of containing a certain proportion of hydrogen phosphate, sodium and sodium dihydrogen phosphate solution in the evaporator concentrate to comply with requirements of the polymeric material spraying. The slurry sprayed into the rotary polymerization furnace, by hot air spray drying and aggregation. After cooling, crushing, sieving of sodium tripolyphosphate product.
Ca5F(PO4)3+5H2SO4+10H2O→3H3PO4+5CaSO4.2H2O+HF
6H3PO4+5Na2CO3→4Na2HPO4+2NaH2PO4+5H2O+5CO2↑
4Na2HPO4+2NaH2PO4→2Na5P3O10+4H2O

3. Hydrogen phosphate disodium salt and sodium dihydrogen phosphate are mixed and heated to 110℃dehydration and continue heating to 540~580℃, dehydration and stable particle type; as heating to 620 ℃, melting cooling to 550 ℃, then cooled in the air, is disintegrated into the powder type. Ethanol in water solution to get six water.

4. Sodium dihydrogen phosphate method will put dihydrogen phosphate adding polymerizer, heating to 700 ℃, dehydrated 15~30min. Then quenched in cold water and processing.

Phosphoric anhydride method
After yellow phosphorus is fused heating tank, enters the combustion furnace, oxided of phosphorus and precipitation. Cools, remove phosphoric anhydride (P2O5). Phosphoric anhydride and sodium carbonate according to 1: 0.8 (mol) cool in a blender mixing into graphite crucible. In 750 to 800 ℃ for indirect heating, dehydration after polymerization to get six partial sodium phosphate melt. Put it into the intraday quench cooling, and get the glass and transparent sodium hexametaphosphate.

Chemical Properties
white or colourless crystals, granules or powder

Uses of Sodium tripolyphosphate (STPP)
Sodium tripolyphosphate is a binder, stabilizer, and sequestrant that is mildly alkaline, with a pH of 10, and moderately soluble in water, with a solubility of 15g in 100ml of water at 25°C. It is used to improve the whipping properties of egg-containing angel food cake mix and meringues. It reduces gelling of juices and canned ham and tenderizes canned peas and lima beans. It is a moisture binder in cured pork and protects against discoloration and reduces shrinkage in sausage products. In algin desserts, it functions as a calcium sequestrant. Sodium tripolyphosphate is also termed pentasodium tripolyphosphate and sodium triphosphate.

Sodium tripolyphosphate is a cross-linker widely used to cross-link polycationic polymers, such as CH, by electrostatic interactions in a process known as ionic gelation (Fig. 2.5). Compared to glutaraldehyde, glyoxal, and other chemical cross-linkers, Sodium tripolyphosphate is physiologically nontoxic. It also has the advantage of being water soluble, and requires only one-step reaction for ionic gelation. Sodium tripolyphosphate has high charge density (six ionic groups), which ensures high cross-linking density with CH amine groups during ionic gelation. It is well established that CH/Sodium tripolyphosphate molar ratio has a profound effect on the resulting NP mean diameter and drug release properties (Gan et al., 2005). Koukaras et al. used computer-aided molecular modeling based on density functional theory to show the most probable cross-linking arrangement of Sodium tripolyphosphate ions within Sodium tripolyphosphate-CH composites (Koukaras et al., 2012). Jonassen et al. investigated the stability of Sodium tripolyphosphate-CH NPs in the presence of sodium chloride salt. They reported maximal instability at the highest Sodium tripolyphosphate-to-CH ratios. They also reported that extreme CH concentration is associated with larger NPs sizes and increased NPs aggregation and sedimentation tendency (i.e., reduced NPs colloidal stability) (Jonassen et al., 2012).

Sodium tripolyphosphate is a very efficient and cost-effective builder. As it is water soluble, and the hardness removal is by chelation, the process is very fast even at low temperatures. Irrespective of these advantages, many countries have stopped using Sodium tripolyphosphate in detergents as it causes environmental problems. Phosphates, being essential nutrients, cause excessive fertilization in stagnant waters and slow-flowing rivers, which leads to excessive growth of algae. These problems can be avoided by employing a wastewater treatment system that removes the phosphorus. However, as aluminosilicates made an entry, it was preferred to limit the use of phosphorus compounds in detergents. Aluminosilicates are environment friendly materials. Aluminosilicates are produced by combining silica and alumina (from bauxite ore). After use in detergents, they are returned to the environment, where they decompose back to silica and alumina. The only concern about the aluminosilicates arises from their insoluble nature. There are some reports of zeolites leading to enhanced sludge in the wastewater. As long as the particles are larger than 1 μm, they can be easily removed by sedimentation. The δ-disilicate, though insoluble during the wash process, dissolves when the solution becomes dilute during the rinse cycle.

What is Sodium tripolyphosphate?
Sodium tripolyphosphate, STPP, is a chemical often used to soak seafood so that it will appear more firm and glossy. It is also known as pentasodium salt or triphosphoric acid. STPP is also an ingredient in detergents and soaps. Most gel, liquid, tablet, and powder forms of both laundry and dishwasher detergent contain STPP. As a food, it is generally regarded as safe, but large ingested amounts of the product can be toxic.

Sodium tripolyphosphate is an umbrella term that refers to multiple combinations of sodium (salt) and phosphate (an inorganic, salt-forming chemical). Food-grade Sodium tripolyphosphate is recognized by the U.S. Food and Drug Administration (FDA) as safe for consumption. It is often used as an additive in processed food manufacturing. It’s also an ingredient in many household products and medications. For some people, Sodium tripolyphosphate may be used to prepare the bowel prior to colonoscopy.

Uses in food
Sodium tripolyphosphate can be found in fast food, deli meat, processed meat, canned tuna, baked goods, and other manufactured foods. It serves a variety of functions:

It thickens food. It stabilizes the texture of processed foods, such as mashed potato mixes.
It cures meat and meat products. It helps to keep deli meats and bacon moist, avoiding spoilage.
It’s a leavening agent. It helps dough rise in commercially prepared cakes and breads and in cake mixes.
It’s an emulsifying agent. It acts as a stabilizer to keep oil and water mixed together in certain types of food, such as processed cheese.
It balances pH levels in processed food. It stabilizes the balance between acidity and alkalinity, extending shelf life and improving taste.

Is it safe to consume?
Food-grade Sodium tripolyphosphate is categorized by the FDA as GRAS, which means “generally recognized as safe.” This may be because the amount of Sodium tripolyphosphate added to processed food, is relatively low.

One studyTrusted Source found that Sodium tripolyphosphate, when used as a food additive, can impact health differently than naturally occurring phosphate. This is because it’s absorbed differently by the body. According to the abstract, high levels of phosphate may elevate mortality rates for the general public, as well as for those with kidney disease and cardiovascular disease. Researchers linked high phosphate levels to accelerated aging and vascular damage. The researchers recommended that people eat foods with naturally occurring phosphates, rather than those with added Sodium tripolyphosphate.

Some athletes take Sodium tripolyphosphate as a supplement to enhance performance. However, a study, reported in the International Journal of Sport Nutrition and Exercise MetabolismTrusted Source, found that supplementation with Sodium tripolyphosphate did not improve aerobic ability in athletes.

Side effects from an overdose of Sodium tripolyphosphate may include:

vomiting
headache
reduced urine output
bloating
abdominal pain
dizziness
irregular heartbeat
seizure

Who should avoid Sodium tripolyphosphate?
Talk to your doctor about your use of Sodium tripolyphosphate, particularly if you take it as a supplement or eat a large amount of processed or fast food.

People with certain conditions should avoid taking this substance. These include:

kidney disease
intestinal tears or blockages
colitis, or slow moving bowels
heart failure
an allergy to Sodium tripolyphosphate

Foods that contain Sodium tripolyphosphate
Foods with naturally occurring Sodium tripolyphosphate include:

nuts and legumes
meat
fish
poultry
eggs
Foods that may have added Sodium tripolyphosphate include:

cured meat
deli meat
fast food
processed foods, such as ready-to-eat meals
commercially prepared baked goods and cake mixes
canned tuna
The takeaway
Sodium tripolyphosphate is naturally occurring in many foods. It’s also added to foods to maintain freshness, alter texture, and achieve a variety of other effects. Sodium tripolyphosphate is considered safe by the FDA but should be avoided by certain people, including those with kidney disease. Make sure to talk to your doctor if you are concerned about your Sodium tripolyphosphate intake or before using it as a supplement.