A colorless solution with a pungent smell, which belongs to the class of strong acids (pH between 0 and 2) and consists of two elements, hydrogen and chlorine. This substance, which is used in various industries due to the neutralization of alkaline factors, is naturally found in the digestive system of most animal species, including humans. Yes, you understood correctly, this substance is the famous hydrochloric acid.

Hydrochloric acid, which is known as muriatic acid or salt, was produced in the early 10th century during an experiment by Abu Bakr Razi (Iranian chemist and physician). At that time Razi was looking for other results from his experiments. For this reason, he came very close to the discovery of hydrochloric acid, but he spared himself from studying the gaseous products resulting from the reaction. Over time, many researchers were inspired by Razi’s experiment and conducted many studies on hydrochloric acid.

In this article, we intend to introduce you to the importance and application of hydrochloric acid, including the extraction of metals. Please stay with us.

Application of hydrochloric acid

Production of organic compounds

One of the applications of hydrochloric acid in the industry is the production of organic compounds such as dichloroethane and vinyl chloride, which are used as raw materials for the production of PVC in the industry.

Production of inorganic (inorganic) compounds

Among the applications of hydrochloric acid used in the industry, we can mention the production of mineral compounds of iron chloride (III) and polyaluminum chloride (PAC). These compounds are used in the wastewater treatment and paper production industry as coagulation and flocculation agents.

Removing metal stains

Although hydrochloric acid has strong corrosive properties, it is used in the industry for acid washing of metals. The ratio of hydrochloric acid used in this work is 1:9 (9 parts of water and 1 part of acid). This process is carried out at high temperatures and removes all rust and contamination on the surface of metals such as copper, iron, brass and other metals.

Cleaning pools

Although pools can be cleaned with other detergents available in the market. But it is not an easy task to remove the stains between the tile joints and water deposits. But it should be noted that the proper concentration of hydrochloric acid is used. The most suitable concentration is the concentration of 1 to 10 acid and water.

Hydrochloric acid in the laboratory

Hydrochloric acid is known as an excellent acid reagent due to its concentration retention over time, high stability, reasonable price and availability. The suitable hydrochloric acid for this field is 37% hydrochloric acid, which is known as laboratory grade hydrochloric acid. Among the laboratory users of this material, we can mention the preparation of glucose from starch, laboratory reagent, acidity regulation (pH control), neutralization of alkaline solutions, catalyst and titration of bases.

Extraction of metals with hydrochloric acid

Until today, you have read or heard many articles that talked about the uses of hydrochloric acid. But one of the important uses of this substance is the extraction of metals, which until now has not been comprehensively discussed about its importance and how to do it.

Earth is made up of precious minerals and metals that our daily lives depend on. For this reason, extracting these materials from mines can boost the economic cycle of a country.

One of the first metals discovered by man is copper. Not having a bond with other elements and being pure was the reason for the discovery of copper in ancient times. But today we get copper from minerals that contain copper compounds. One of the most common methods of separating metal ions is solvent extraction. This method is done by mixing the aqueous phase containing the metal salt with the organic metal of the extraction agent. The advantage of solvent extraction of metals is the easy change of parameters controlling the extraction, such as the pH of the aqueous solution and the diluent. However, due to the use of organic solvents in high volumes, which are often toxic or flammable, this method is not compatible with the environment. Hydrochloric acid is one of the solvents used in this method.

The solubility of metals in this acid depends on factors such as ion charge, ion size and ion mobility. For example, the mineral chalcopyrite, which contains copper, sulfur and iron atoms, is naturally extracted from mines. This mineral causes high damage to the equipment due to the production of sulphurous gas compounds, high temperature and pressure conditions in the oxidation method. For this reason, they use hydrochloric acid to extract valuable metals in minerals. During the process, parameters such as temperature, acid concentration, oxidizing agents, soluble salts, extraction time, metal ion activity, and chlorine gas amount are regularly checked.

Solvent extraction of metals is used not only for ores and minerals, but also for other products that contain different amounts of metal ions. It should also be noted that the best solvents for metal extraction are acids, and among all acids, hydrochloric acid and phosphoric acid have high efficiency.