Phosphorous acid

Phosphorous acid is a white crystalline solid or aqueous solution, typically traded at 70% concentration.

Where is Phosphorous acid used?

• Water treatment: scale inhibitor and corrosion control agent in cooling water systems
• Agriculture: precursor to phosphonate-based fungicides and active component against oomycete pathogens
• Textile and leather processing: pH regulation during dyeing and tanning
• Pharmaceutical and chemical manufacturing: reducing intermediate in synthesis and stabilizer against metal-catalyzed oxidation
• It controls pH, sequesters metal ions, and stabilizes formulations against oxidative degradation.

Good to know: Technical grade is standard for industrial applications; higher purity grades are available for pharmaceutical synthesis and specialty chemical manufacturing.

Commercial specifications

• 70% aqueous solution concentration
• Higher purity grades for pharmaceutical synthesis