Acids & Salts Available — Bulk Only

Magnesium Sulfate (Anhydrous)

CAS 7487-88-9 · Formula MgO4S · MW 120.37 g/mol

A dependable anhydrous desiccant and magnesium feedstock for fertilizer, textile, leather, and nutritional uses. It serves as a drying and dehydrating agent and is used across fertilizer manufacture, textile weighting and dyeing, leather tanning, and as a magnesium nutrient source in feed and food.

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HS Code
2833.21
At a Glance
Material Family
Acids & Salts
Record Type
Pure compound
Primary Role
Thickening / Rheology · Viscosity Modification
Solubility
710 mg/mL
Functional Roles
MAGNESIUM SULFATE
BULKINGVISCOSITY CONTROLLING
Applications & Use Cases
  • Desiccant: Dehydrating and drying agent for solvents and processes
  • Fertilizers: Soluble magnesium and sulfur nutrient source
  • Textiles: Weighting, dyeing, and printing aid for cotton and silk
  • Leather: Tanning auxiliary
  • Feed and food: Magnesium nutrient supplement
Physical Properties
Melting Point
1124 °C (decomposition)
Density
2.66 g/cu cm
Solubility
710 mg/mL
pH
Neutral to litmus
Safety & Handling
Full SDS available on request

A grade-specific Safety Data Sheet (SDS) — with the complete hazard classification, handling precautions, and transport information — is supplied with every shipment and available on request. Confirm all safety and regulatory details against the SDS for your specific grade.

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HS / Tariff Classification
Harmonized System (HS) Code — 6-digit international heading
2833 . 21
Chapter 28
Inorganic chemicals; compounds of precious metals and rare-earth metals
Heading 28.33
Internationally harmonized (WCO HS)
Subheading 2833.21
6-digit international code — national tariff line adds further digits
Chemical Identity
CAS Number
7487-88-9
Molecular Formula
MgO4S
Molecular Weight
120.37 g/mol
IUPAC Name
magnesium sulfate
INCI Name
MAGNESIUM SULFATE
PubChem CID
InChI Key
CSNNHWWHGAXBCP-UHFFFAOYSA-L
Synonyms & Trade Names
MAGNESIUM SULFATE Magnesium sulfate anhydrous MgSO4 Sulfuric acid magnesium salt (1:1) Magnesiumsulfat Magnesium sulfate (1:1) Sal Angalis Sal De sedlitz Tomix OT Sulfuric acid magnesium salt Magnesium(II) sulfate Magnesium sulfate,anhydrous Magnesium sulphate anhydrous Magnesium sulphate, anhydrous Magnesium Sulfate In Plastic Container Magnesium sulfate in dextrose 5% in plastic container
Full Description

Anhydrous magnesium sulfate (CAS 7487-88-9, MgSO4) is supplied as a USP-grade powder. It serves as a drying and dehydrating agent and is used across fertilizer manufacture, textile weighting and dyeing, leather tanning, and as a magnesium nutrient source in feed and food.

Frequently Asked Questions

What is anhydrous magnesium sulfate used for?

Anhydrous magnesium sulfate (CAS 7487-88-9, MgSO4) is used industrially as a drying and dehydrating agent for solvents and process streams, as a soluble magnesium and sulfur nutrient in fertilizers, as a weighting and dyeing aid in textile processing, as a tanning auxiliary in leather, and as a magnesium source in feed and food. We supply it as a USP-grade powder in bulk.

Is magnesium sulfate (USP) the same as Epsom salt?

Epsom salt is magnesium sulfate heptahydrate (MgSO4·7H2O), the hydrated crystalline form. The USP anhydrous powder we supply is the water-free form (MgSO4) with no waters of crystallization, so its magnesium content per unit weight is higher. Both share CAS-family identity but differ in hydration state, density, and handling.

What is the difference between magnesium sulfate and anhydrous magnesium sulfate?

The difference is bound water. Standard magnesium sulfate is typically the heptahydrate (MgSO4·7H2O); the anhydrous grade contains no waters of hydration, which is why it functions as an effective desiccant. Anhydrous powder carries a higher MgSO4 assay per kilogram and is preferred where moisture must be excluded.

Is anhydrous magnesium sulfate water soluble?

Yes. Magnesium sulfate is freely water soluble; the anhydrous form is strongly hygroscopic and dissolves readily, releasing heat as it hydrates. This solubility underlies its use as a drying agent and as a soluble Mg/S nutrient source. Consult the SDS for handling of the hygroscopic powder.

What is the cost of bulk anhydrous magnesium sulfate USP?

Bulk pricing depends on volume, packaging (bags, drums, supersacks), and delivery point. RawSource supplies USP anhydrous magnesium sulfate powder by the drum, tote, or truckload — request a bulk quote and we will return current pricing with a CoA and SDS.

Disclaimer. Information on this page — including properties, identifiers, hazard, transport (DOT/UN) and tariff (HS) classifications, and applications — is provided for general reference and is compiled from authoritative public sources (e.g. PubChem/ECHA, 49 CFR 172.101, the Harmonized Tariff Schedule). Values are typical and are not a guaranteed specification; the Certificate of Analysis (CoA) for the lot purchased governs. Products are sold for industrial and professional use only. Nothing here is a medical, health, or efficacy claim or advice. Always consult the current Safety Data Sheet (SDS) before handling, storage, transport or disposal, and confirm regulatory status, classification and suitability for your application and jurisdiction. Hazard, transport and tariff classifications must be verified for your specific shipment. RawSource makes no warranty, express or implied, and assumes no liability for use of this information. Trademarks. Third-party trademarks and brand names are the property of their respective owners; any reference is nominative — used only to identify a comparable product — and does not imply affiliation with, sponsorship by, or endorsement by the trademark owner.