Industrial Grade Phosphorous Acid (H3PO3) CAS 13598-36-2 Reducing Agent & Chemical Intermediate

Phosphorous Acid (H3PO3, CAS:13598-36-2,EINECS:237-066-7, HS Code:28111990, molecular formula H3PO3, MW: 82.00) is an inorganic diprotic acid appearing as white deliquescent crystalline solid or colorless transparent liquid (70% concentration). Also known as phosphonic acid, it has a phosphorus valence of +3, giving it strong reducing properties. Manufactured by hydrolysis of phosphorus trichloride or reaction of phosphorus with water, our industrial grade product complies with HG/T 2520-2023 and international quality standards. It is highly soluble in water and alcohol, slowly oxidizes to phosphoric acid in air, and decomposes into phosphoric acid and toxic phosphine gas at 180°C. As a versatile chemical, it is widely used as reducing agent, chemical intermediate and corrosion inhibitor in various industrial sectors.

Applications
Chemical Synthesis (Core Application)
Key intermediate for glyphosate herbicide production (condensation with iminodiacetic acid to form N-phosphonomethyliminodiacetic acid)
Raw material for manufacturing phosphite salts (potassium, calcium, aluminum, ammonium phosphites)
Reducing agent in organic synthesis reactions, efficiently reducing silver, gold and other metal ions
Precursor for phosphonate compounds used in water treatment (ATMP, HEDP)
Water Treatment Industry
Excellent corrosion and scale inhibitor for industrial cooling water systems
Stabilizer for metal surfaces, forming protective phosphate films
Reducing agent for removing heavy metals from wastewater
Plastic & Polymer Industry
Raw material for plastic stabilizers (e.g., dibasic lead phosphite) to improve heat resistance and weatherability
Flame retardant additive for polycarbonate and other engineering plastics
Catalyst in polyester and epoxy resin synthesis
Other Industrial Applications
Metal surface treatment: used for pickling and brightening of non-ferrous metals
Electroplating industry: reducing agent for electroless nickel plating baths
Agriculture: component of fungicides and plant nutrient solutions
Pharmaceutical industry: intermediate for certain drug synthesis

Product Advantages
✅ Strong reducing property: High reactivity for various reduction reactions
✅ Dual form availability: Solid (≥99.0%) and liquid (70%) to meet different processing needs
✅ High purity: Low impurity content (phosphate, chloride, sulfate) ensuring product quality
✅ Excellent solubility: Easily dissolves in water and alcohols for convenient application
✅ Versatile functionality: Serves as reducing agent, intermediate, corrosion inhibitor and stabilizer
✅ Complete certification: Complies with industrial standards, full test reports and export documents

Packaging & Storage
Solid product: 25kg fiber drums with inner PE liner or 1000kg FIBC bulk bags. Liquid product: 200L HDPE drums or ISO tank containers (20-25 tons). The product is highly deliquescent and corrosive. Store in a cool, dry and well-ventilated warehouse, separate from oxidants, strong bases and food additives. Keep containers tightly sealed to prevent moisture absorption and contamination. Shelf life is 12 months under proper storage conditions.

Safety Information
Classified as Class 8 Corrosive Substance for international transportation (UN 3264). It is corrosive to skin, eyes and respiratory tract. Fine dust or mist may cause severe irritation, burns and tissue damage. Wear acid-resistant gloves, goggles, face shield and dust mask during handling. In case of contact, immediately rinse with plenty of clean water for at least 15 minutes and seek medical attention if irritation persists. Avoid inhalation and ingestion. Complete MSDS and safety certificates can be provided upon request.

With 15 years of experience in chemical foreign trade, we offer the following core strengths to support your procurement needs:
1.A 70,000 ㎡ warehouse (20,000 MT capacity) with moisture-proof and temperature-controlled systems, enabling efficient fulfillment of large-volume orders. 2.Free samples (Ship within 3-7 days) to let you test products at zero trial cost. 3.Transparent lead time for hazardous chemicals: 45–60 days, with clear delivery schedules. 4.Certified with a Hazardous Chemical Business License and ISO certification, ensuring smooth customs clearance. 5.6 packaging options with customizable logos to minimize product loss during transportation. 6.Over 400 chemical SKUs available for one-stop procurement, helping you reduce sourcing costs.
Please share your purchase volume, target market, and other requirements, and we will tailor a customized solution for you!