What is Sodium Tripolyphosphate CAS 7758-29-4?

Sodium tripolyphosphate, commonly called STPP, is an inorganic condensed phosphate supplied as a white granular or powdered solid. It is widely used as a builder in detergents and as a sequestrant, dispersant and water softener.

How does STPP differ from trisodium phosphate?

STPP is a condensed polyphosphate containing three phosphorus atoms linked through oxygen bridges, while trisodium phosphate is a simple orthophosphate. STPP provides stronger calcium and magnesium sequestration, dispersion and detergent-building performance.

Why does the Phase I to Phase II ratio matter?

STPP can exist in different hydrated crystalline forms, often called Phase I and Phase II. Their ratio affects hydration rate and detergent-slurry processing behavior, so manufacturers often specify the preferred ratio for their production line.

What are the main applications?

Major uses include laundry and dishwashing detergents, industrial cleaners, water treatment, ceramic processing, mineral flotation, textile auxiliaries and food processing where an appropriate food-grade material is required.

Which grades and packaging are available?

The listing covers industrial/detergent grade, with food grade available on request. Packing includes 25 kg bags, jumbo bags or customized packaging according to order volume and delivery requirements.

What specifications should be checked before ordering?

Confirm grade, P2O5 content, pH, whiteness, water-insoluble matter, heavy metals, particle size and any food-grade requirements. Request the batch analysis, technical data and safety information before purchase.

How should STPP be stored and handled?

Store in a cool, dry, ventilated area in tightly closed containers away from moisture, acids and incompatible materials. Use dust-control measures and suitable respiratory protection, and avoid releasing material to drains without appropriate treatment.

Sodium Tripolyphosphate CAS 7758-29-4

Sodium Tripolyphosphate (STPP), CAS 7758-29-4, is a white, free-flowing inorganic phosphate supplied as a builder, sequestrant and dispersing agent. Confirm the required grade, then request a quotation with COA/TDS/SDS for bulk supply.

CAS: 7758-29-4
Synonyms: STPP, Pentasodium triphosphate, Sodium triphosphate, Triphosphoric acid pentasodium salt, Pentasodium tripolyphosphate
Einecs: 231-838-7
Molecular Formula: Na₅P₃O₁₀
Grade: Industrial / Detergent Grade, Food Grade (on request)
Package: 25 kg bags, jumbo bags or customized packing

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Product Description

Sodium Tripolyphosphate, CAS 7758-29-4, also known as STPP or pentasodium triphosphate, is an inorganic condensed phosphate; the EC/EINECS number is 231-838-7.

Synonyms: STPP; pentasodium triphosphate; sodium triphosphate; triphosphoric acid pentasodium salt; pentasodium tripolyphosphate.

CAS: 7758-29-4.

Molecular formula: Na₅P₃O₁₀.

Molecular weight: about 367.86 g/mol.

EC number: 231-838-7.

It is a white powder or granular solid, easily soluble in water and insoluble in alcohol, slightly hygroscopic.

The assay (Na₅P₃O₁₀) is ≥94.0% (industrial) or ≥95.0% (food); P₂O₅ content is ≥56.0–57.0%.

A 1% aqueous solution at 25 °C has a pH of 9.2–10.0; water insolubles are ≤0.1%.

It is used as a builder, sequestrant and dispersing agent in laundry and dishwashing detergents and industrial cleaners.

It is used in water treatment, ceramic processing, mineral flotation and textile auxiliaries.

It is used in food processing where an appropriate food-grade material is required.

STPP is a condensed polyphosphate providing strong calcium and magnesium sequestration and detergent-building performance.

Confirm grade, P₂O₅ content, pH, whiteness, water-insoluble matter, heavy metals, particle size and food-grade requirements.

Store in a cool, dry, ventilated area in tightly closed containers away from moisture, acids and incompatible materials.

Confirm packaging with the requested quantity and destination requirements.

Document requirements should be confirmed from the current specification, SDS, COA or other product-specific files.

The page is an RFQ entry point and does not state stock, price, MOQ or fixed lead time.

For an RFQ, state the intended use, required grade, quantity, packaging, destination and document needs.

FAQ - Technical & Supply Chain

Q:
What is Sodium Tripolyphosphate CAS 7758-29-4?

A: Sodium tripolyphosphate, commonly called STPP, is an inorganic condensed phosphate supplied as a white granular or powdered solid. It is widely used as a builder in detergents and as a sequestrant, dispersant and water softener.
Q:
How does STPP differ from trisodium phosphate?

A: STPP is a condensed polyphosphate containing three phosphorus atoms linked through oxygen bridges, while trisodium phosphate is a simple orthophosphate. STPP provides stronger calcium and magnesium sequestration, dispersion and detergent-building performance.
Q:
Why does the Phase I to Phase II ratio matter?

A: STPP can exist in different hydrated crystalline forms, often called Phase I and Phase II. Their ratio affects hydration rate and detergent-slurry processing behavior, so manufacturers often specify the preferred ratio for their production line.
Q:
What are the main applications?

A: Major uses include laundry and dishwashing detergents, industrial cleaners, water treatment, ceramic processing, mineral flotation, textile auxiliaries and food processing where an appropriate food-grade material is required.
Q:
Which grades and packaging are available?

A: The listing covers industrial/detergent grade, with food grade available on request. Packing includes 25 kg bags, jumbo bags or customized packaging according to order volume and delivery requirements.
Q:
What specifications should be checked before ordering?

A: Confirm grade, P2O5 content, pH, whiteness, water-insoluble matter, heavy metals, particle size and any food-grade requirements. Request the batch analysis, technical data and safety information before purchase.
Q:
How should STPP be stored and handled?

A: Store in a cool, dry, ventilated area in tightly closed containers away from moisture, acids and incompatible materials. Use dust-control measures and suitable respiratory protection, and avoid releasing material to drains without appropriate treatment.

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