Magnesium Sulfate (MgSO₄·xH₂O)
CAS No:
Anhydrous: 7487-88-9
Heptahydrate (Epsom Salt): 10034-99-8
Molecular Formula: MgSO₄·xH₂O
Molecular Weight:
Anhydrous: 120.37 g/mol
Heptahydrate: 246.47 g/mol
1. Product Description
Magnesium sulfate is an inorganic salt consisting of magnesium, sulfur, and oxygen. The heptahydrate (MgSO₄·7H₂O) is commonly known as Epsom Salt and appears as colorless or white crystals. It is widely used in agriculture (fertilizer, micronutrient), pharmaceuticals (oral, injectable, topical), food fortification, and industrial processes.
2. Specifications – Industrial / Technical Grade (MgSO₄·7H₂O)
| Item | Specification / Typical Value | Notes |
|---|
| Appearance | White crystalline solid | Free-flowing |
| Assay (MgSO₄·7H₂O) | ≥ 99.0 % | Gravimetric |
| Magnesium (Mg) Content | ≥ 9.6 % | ICP / AAS |
| Sulfur (S as SO₄) | ≥ 12.9 % | Gravimetric |
| Moisture | Meets theoretical for heptahydrate | Stability check |
| Water-Insoluble Matter | ≤ 0.05 % | Filtration residue |
| pH (5 % solution) | 5.0 – 7.0 | 20 – 25 °C |
| Iron (Fe) | ≤ 0.001 % (10 ppm) | ICP |
| Heavy Metals (as Pb) | ≤ 20 ppm | ICP |
| Lead (Pb) | ≤ 10 ppm | ICP |
| Arsenic (As) | ≤ 2 ppm | ICP |
| Cadmium (Cd) | ≤ 1 ppm | ICP |
| Bulk Density | ~1.65 g/cm³ | Typical value |
| Solubility | Freely soluble in water | 71 g/100 mL at 20 °C |
Typical Applications:
Agricultural fertilizers (magnesium source), feed additives, leather processing, textile finishing, chemical manufacturing, pulp & paper.
3. Specifications – Food / Pharmaceutical Grade (FCC / USP / EP)
| Item | Specification / Typical Value | Reference |
|---|
| Appearance | White crystalline granules or powder | FCC / USP |
| Identification | Passes tests for magnesium and sulfate | USP / EP |
| Assay (MgSO₄·7H₂O) | 99.0 – 100.5 % | USP |
| Magnesium (Mg) | Consistent with assay | ICP |
| pH (5 % solution) | 5.0 – 9.2 | USP |
| Chloride (Cl⁻) | ≤ 0.014 % | USP |
| Calcium (Ca) | ≤ 0.01 % | USP |
| Iron (Fe) | ≤ 20 ppm | USP |
| Heavy Metals (as Pb) | ≤ 10 ppm | USP |
| Arsenic (As) | ≤ 1–2 ppm (depending on pharmacopeia) | ICP |
| Loss on Ignition | Meets theoretical for heptahydrate | USP |
| Microbiological Limits | Total plate count ≤ 10³ cfu/g; Pathogens negative | GMP requirement |
| Solubility Test | Clear, colorless solution | FCC |
Typical Applications:
Laxatives, electrolyte replenishment (oral or injectable), hemodialysis solutions, food fortification, brewing, nutritional supplements.
4. Physical & Chemical Properties
Appearance: White crystals or crystalline powder
Density: ~2.66 g/cm³ (heptahydrate)
Melting Point: 150 °C (loses water of crystallization)
Solubility: Highly soluble in water; insoluble in ethanol
Taste: Characteristic saline, bitter
5. Storage & Handling
Store in a cool, dry, well-ventilated area.
Keep container tightly closed to avoid moisture uptake or caking.
Avoid contamination with incompatible materials (strong acids/bases).
Follow good industrial hygiene practices; use dust protection when handling powders.
6. Packaging
Industrial Grade: 25 kg / 50 kg woven bags, jumbo bags available.
Food / Pharma Grade: 25 kg multi-layer paper bags with polyethylene liner or fiber drums, compliant with GMP / HACCP.
For more information, please visit this website:https://www.khonorchem.com
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