Phosphoric acid (H3PO4) is the leading inorganic acid produced and consumed in terms of production value and it is the second largest in terms of volume—after sulfuric acid. By far its greatest use is in the manufacture of phosphate chemicals consumed primarily as carriers of phosphorus values in fertilizers. Use in the production of animal feeds is of secondary importance. Phosphoric acid is also used in the manufacture of phosphate chemicals for use in water treatment and detergent builders, dentifrices, fire control chemicals, and a host of smaller markets. In the following, we want to mention the Applications of phosphoric acid in industry.
The primary market for phosphoric acid is the production of the phosphate fertilizer products—ammonium phosphates and triple superphosphates. Fertilizer production accounts for an estimated 80% of the global market for phosphoric acid and animal feed for about 6%. The remainder is consumed in a variety of industrial Applications Phosphoric acid.
Applications of phosphoric acid in industry: Industrial uses As a cleanser for metals, phosphoric acid produces a light etch on steel, aluminum, or zinc, which aids paint adhesion. Deoxidine is a phosphoric acid cleanser for metals. Nielite D is phosphoric acid with a rust inhibitor, used as a nonfuming pickling acid for steel. Phosphoric anhydride, or phosphorus pentoxide, P2O5, is a white, water-soluble powder used as a dehydrating agent and also as an opalizer for glass. It is also used as a catalyst in asphalt coatings to prevent softening at elevated temperatures and brittleness at low temperatures.
Safety Profile Human poison by ingestion. Moderately toxic by skin contact. A corrosive irritant to eyes, skin, and mucous membranes, and a systemic irritant by inhalation. A common air contaminant. A strong acid. Mixtures with nitromethane are explosive. Safety In the concentrated form, phosphoric acid is an extremely corrosive and harmful acid. However, when used in pharmaceutical formulations it is usually very diluted and is generally regarded as an essentially nontoxic and nonirritant material. The lowest lethal oral dose of concentrated phosphoric acid in humans is reported to be 1286 mL/kg.
Other Applications of phosphoric acid in industry: Potential Exposure Phosphoric acid is used in the manufacture of fertilizers, phosphate salts; polyphosphates, detergents, activated carbon; animal feed; ceramics, dental cement; pharmaceuticals, soft drinks; gelatin, rust inhibitors; wax, and rubber latex. Exposure may also occur during electropolishing, engraving, photoengraving, lithographing, metal cleaning; sugar refining; and water-treating.
Phosphoric acid (H3PO4) can be produced by 3 main commercial methods: wet process, thermal process and dry kiln process. Wet process is by far the most common route and the acid can be used in phosphate fertilizers production (DAP, MAP, SPA). Thermal process phosphoric acid is of a much higher purity and is used in the manufacture of high grade chemicals, pharmaceuticals, detergents, food products, and other nonfertilizer products. The last method, using a rotary kiln, is a promising alternative because of its reduced environmental footprint and potential cost saving.
The concentration of phosphoric acid is normally expressed as % P2O5 (percent phosphoricanhydride) rather than % H3PO4 (percent phosphoric acid). In a wet process facility , phosphoric acid is produced by reacting sulfuric acid (H2SO4) with naturally occurring phosphate rock. The reaction also forms calcium sulfate (CaSO4), commonly referred to as gypsum.
Phosphoric acid is a weak and chemical organic acid. Phosphoric acid has many applications in industry. This substance is used in products such as fertilizers, pharmaceuticals, rust removal of metals, etc. This acid is produced by both wet and dry processes.