Description

Sulphuric Acid Specification

1. General Information

• Chemical name: Sulphuric Acid
• Formula: H₂SO₄
• CAS Number: 7664-93-9
• Appearance: Clear, colorless to slightly yellow oily liquid
• Odor: Odorless (may have sharp acidic fumes in impure form)
• Hazard class: Corrosive (UN 1830 / UN 2796 depending on concentration)

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2. Typical Commercial Grades

A. Concentrated Sulphuric Acid (Industrial Grade)

• Purity (H₂SO₄): 98.0–98.5% min
• Density (20°C): 1.83–1.84 g/cm³
• Boiling point: ~337°C
• Free SO₃: ≤ 0.5%
• Iron (Fe): ≤ 50 ppm (varies by grade)
• Chlorides (Cl⁻): ≤ 10–50 ppm
• Arsenic (As): ≤ 1–5 ppm
• Residue after ignition: ≤ 0.02%

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B. Battery Acid Grade (Diluted Sulphuric Acid)

• Concentration: 30–38% H₂SO₄
• Density: ~1.22–1.28 g/cm³
• Iron (Fe): ≤ 10–30 ppm
• Chlorides: Very low (battery grade requires high purity)
• Use: Lead-acid batteries, UPS systems, automotive batteries

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C. Technical / Fertilizer Grade

• Purity: 93–98%
• Free SO₃: 0.5–1.5%
• Iron (Fe): ≤ 100 ppm
• Color: Slight yellow tint acceptable
• Use: Fertilizer production, phosphate processing, mining

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3. Physical & Chemical Properties

• Molecular weight: 98.08 g/mol
• Melting point: 10.3°C (concentrated acid crystallizes at low temperature)
• Solubility: Fully miscible with water (highly exothermic reaction)
• pH: < 1 (strong acid)
• Viscosity: High (oily consistency at 98%)

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4. Quality Parameters (Typical ISO/Industrial Limits)

• H₂SO₄ content: ≥ 98%
• SO₃ (free): ≤ 0.5%
• Iron: ≤ 50 ppm
• Chlorides: ≤ 10–50 ppm
• Heavy metals: trace levels only
• Organic matter: nil or trace