Product Overview
Phosphoric Acid 85% Technical Grade is a concentrated inorganic acid supplied as a clear, colorless viscous liquid. At 85% concentration, this is the standard industrial-strength form of orthophosphoric acid (H₃PO₄), used across metal finishing, water treatment, fertilizer production, and chemical manufacturing. It is available to order in sizes from single quarts through 330-gallon totes, covering bench-scale trials through continuous production lines.
Why This Concentration
85% represents the highest practical liquid concentration of phosphoric acid before the material begins to crystallize. For metal treatment baths, rust conversion, and surface preparation, this concentration delivers maximum reactivity per unit volume — operators dilute to their target strength on site rather than paying freight on water. Technical grade is the right procurement choice for industrial processes where the cost premium of an analytical or reagent designation adds no functional value to the reaction. If your operation calls for surface preparation, pH adjustment, or phosphate synthesis, technical grade performs the same chemistry at a lower landed cost.
Chemical Profile
Phosphoric Acid 85% Technical Grade (CAS 7664-38-2, molecular formula H₃PO₄, molecular weight 97.995) presents as a clear, colorless viscous liquid with no detectable odor. Its density is 1.685 at 25 °C in the 85% solution — noticeably heavier than water, which matters for metering pumps and tank design. The solution is fully miscible with water at all proportions. Vapor pressure is low at 0.3 kPa (20 °C), meaning minimal fuming under normal storage and handling conditions.
Industrial Applications
Phosphoric acid at this concentration serves multiple industrial sectors. The applications below reflect well-established uses of this chemical.
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Metal Treatment and Surface Preparation — Phosphoric acid converts iron oxide (rust) to iron phosphate, creating a stable, paintable surface. Metal fabricators use it for pickling, passivation, and pre-treatment before coating or welding. The 85% concentration lets operators prepare working baths at the exact dilution their process demands.
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Fertilizer Production — Phosphoric acid is the primary feedstock for manufacturing phosphate fertilizers including MAP (monoammonium phosphate) and DAP (diammonium phosphate). Agricultural chemical producers use technical grade acid as their starting material for granulation and blending.
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Water Treatment and pH Control — Water treatment operators use phosphoric acid to lower pH in alkaline process streams. It also contributes phosphate ions for corrosion inhibition in municipal and industrial water systems, where controlled dosing adjusts alkalinity without introducing chloride or sulfate ions.
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Chemical Synthesis — Phosphoric acid serves as a reactant and catalyst in the production of phosphate esters, detergent builders, and other phosphorus-containing intermediates. Starting at 85% minimizes dilution steps in batch formulations.
Handling & Storage
Phosphoric Acid 85% carries a signal word of Danger (per the product's GHS classification). Two hazard statements apply: H314 — Causes severe skin burns and eye damage, and H290 — May be corrosive to metals (per the product's GHS classification). Operators should wear chemical-resistant gloves, splash goggles, and a face shield when transferring or diluting. Use HDPE, polypropylene, or glass-lined containers — phosphoric acid will attack mild steel and most common metals over time. Store in a cool, dry area with secondary containment, and keep containers sealed. Although vapor pressure is low, prolonged exposure to moisture can alter concentration. Ensure adequate ventilation in enclosed storage areas and keep away from incompatible materials such as strong bases and reactive metals.
Hazmat & Shipping
Phosphoric Acid 85% Technical Grade is classified as a hazardous material for transport:
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UN Number: UN1805 (per 49 CFR 172.101)
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Hazard Class: 8 — Corrosive (per 49 CFR 172.101)
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Packing Group: III (per 49 CFR 172.101)
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Proper Shipping Name: Phosphoric acid solution (per 49 CFR 172.101)
All shipments are prepared with required hazmat documentation, labeling, and packaging from our Taylor, TX facility. Drums and totes are palletized per DOT requirements.
Documentation
A Safety Data Sheet (SDS) ships with every order and is available in English, Spanish, French, and Japanese. A Technical Data Sheet (TDS) is available on request. Lot-specific Certificates of Analysis (COA) can be provided to support your incoming QC requirements.
Why Buy from Alliance Chemical
This product is available to order in configurations from single quarts for bench work to 330-gallon bulk totes for continuous production — each packaged, labeled, and shipped as a Class 8 corrosive with full DOT hazmat documentation. Alliance Chemical has served over 50,000 customers since 1998, operating from our facility at 204 S Edmond St, Taylor, Texas 76574. All shipping and handling guidance on this page is reviewed by Andre Taki, DOT Hazmat Specialist.