Chemistry · June 11, 2022

How is Phosphoric Acid made?

Phosphoric acid is a strong mineral acid with many industrial uses. The most common source for producing phosphoric acid is natural minerals, such as phosphate ore. Phosphate ore must first be processed to make it suitable for producing phosphoric acid.

Other names for phosphoric acid are: orthophosphoric acid, hydrogen phosphate, or monomethyldiphosphoricacid. It’s an inorganic chemical that serves many industrial purposes. Its primary use is as a food additive to assist in the fermentation of alcohol when making vinegar. It’s also used to bleach and whiten sugar and flour to improve their appearance and shelf life; it’s also used as an additive in sodas, juices, and other carbonated drinks to add an acidic taste.
Its other uses include metalworking fluids; mold release agents; cleaning solutions; flameproofing materials; corrosion inhibitors; metal finishing aids; drilling fluids; and water treatment chemicals. Let’s take a look at how this substance can be produced at home or on a smaller scale production plant.

 

How is Phosphoric Acid made?

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Phosphoric acid is a clear, syrupy liquid that has many industrial uses. It is used in metal cleaning solutions, as a preservative in food and as an additive to motor oils. The manufacturing of phosphoric acid involves the reaction of phosphorus with sulfuric acid and water. Both natural sources of these chemicals are exploited to manufacture phosphoric acid. This article explains how phosphoric acid is made and its chemical properties.

What is Phosphorus?

Phosphorus is a reactive non-metal that is a constituent of all living organisms. It is an essential element for all living plants and animals, where it is mainly used in the construction of DNA and in cellular energy transfer. The phosphorus cycle describes the movement of elements between living and non-living systems, as well as the cycling of phosphorus within these systems. The majority of phosphorus in natural environments exists in the form of minerals such as apatite, which are mined for industrial use. Phosphorus is mined from two types of ore: phosphate rock, which contains the minerals apatite, fluorapatite, and iron phosphate, and phosphorite, a phosphate-bearing rock that is rich in phosphate. Phosphorus can also be obtained from the incineration of organic material.

How is Phosphoric Acid Made?

The first step in the manufacturing of phosphoric acid is to produce elemental phosphorus, which is done by heating phosphate rock or phosphate-containing wastes. Phosphorus reacts with sulfuric acid, water and carbon dioxide to produce phosphoric acid: This reaction is conducted in the liquid state, at a temperature between 110° and 250° C (230° and 480° F). Phosphoric acid is an inorganic acid that is hygroscopic (attracts and retains moisture) and is not corrosive until it is concentrated. The acid is colourless or light yellow, and has a sour taste. It is a viscous liquid that is miscible (mixes evenly) with water, alcohol and many organic compounds. It reacts with most metals, forming salts.

Properties of Phosphoric Acid

– Phosphoric acid is a clear, syrupy, colourless liquid at room temperature. – It has an acidity of about 85% at a concentration of about 68%. – It is an inorganic acid that is hygroscopic (attracts and retains moisture) and is not corrosive until it is concentrated. – It is a viscous liquid that is miscible (mixes evenly) with water, alcohol and many organic compounds. – It reacts with most metals, forming salts. – It is manufactured from the reaction of phosphorus with sulfuric acid and water. – It is used in metal cleaning solutions, as a preservative in food and as an additive to motor oils.

Uses of Phosphoric Acid

The uses of phosphoric acid include its use in metal cleaning solutions, as a preservative in food and as an additive to motor oils. It is also used in the manufacture of dyes, fertilizers, and pesticides. Phosphoric acid is also used to produce phosphate salts that are important in many industries, including the textile, chemical, and papermaking industries. In the food industry, phosphoric acid is used as a condiment and in cola drinks.

Side Effects of Phosphoric Acid

Phosphoric acid is used as a cleaning agent for metals because it is a strong acid. However, when it comes into contact with skin, it may cause eczema and dermatitis, especially in individuals who have sensitive skin. In extreme cases, it may even cause blisters. Phosphoric acid is corrosive to the teeth and digestive tract, so those in the food industry who work with phosphoric acid should avoid eating or drinking it. When phosphoric acid is ingested, it may cause gastrointestinal problems such as nausea, vomiting, diarrhea, and abdominal pain. Ingestion of large amounts of phosphoric acid can lead to metabolic acidosis and hypocalcemia.

Making of Polyphosphoric Acids

When phosphorus is reacted with sulfuric acid, excess acid reacts with water to produce hydrochloric acid and phosphoric acid. The phosphoric acid formed is a mixture of monohydrogen and dihydrogen phosphate (polyphosphoric acid). It is possible to purify the polyphosphoric acid by the crystallization of the acid from the solution. When the solution is seeded with phosphoric acid crystals, the non-crystalline impurities are slowly dissolved and the remaining crystals are removed. The resulting product is mono- and dihydrogen phosphate, which is further reacted with hydrogen to make phosphoric acid.

Conclusion

Phosphoric acid is a clear, syrupy liquid that has many industrial uses. The manufacturing of phosphoric acid involves the reaction of phosphorus with sulfuric acid and water. Phosphorus reacts with sulfuric acid, water and carbon dioxide to produce phosphoric acid. Phosphoric acid is an inorganic acid that is hygroscopic (attracts and retains moisture) and is not corrosive until it is concentrated. It is a viscous liquid that is miscible (mixes evenly) with water, alcohol and many organic compounds. Phosphoric acid is used in metal cleaning solutions, as a preservative in food and as an additive to motor oils. When ingested, it may cause gastrointestinal problems such as nausea, vomiting, diarrhea, and abdominal pain. Phosphoric acid is also used to produce polyphosphoric acids, which are further reacted with hydrogen to make phosphoric acid.