Hydrochloric acid is a strong inorganic acid and has a wide range of applications in industrial processing, such as metal refining. Hydrochloric acid often determines the quality of the product.
In analytical chemistry, when an acid is used to measure the concentration of a base, it is generally titrated with hydrochloric acid. Titration with a strong acid can make the endpoint more visible and the results obtained are more accurate. At 1 standard atmospheric pressure, 20.2% hydrochloric acid can form a constant boiling solution, which is often used as a reference in quantitative analysis at a certain pressure. The concentration at constant boiling changes with the change in gas pressure.
Hydrochloric acid is commonly used to dissolve solid samples for further analysis, including the dissolution of some metals and the formation of readily soluble materials such as calcium carbonate or copper oxide for convenient analysis.
One of the most important uses of hydrochloric acid is pickling steel. The surface rust or iron oxide can be reacted with hydrochloric acid before subsequent treatment of iron or steel (extrusion, rolling, galvanizing, etc.). Carbon steel is usually washed with a hydrochloric acid solution having a concentration of 18% as an acid pickling agent.
The remaining spent acid is often used as a ferrous chloride solution, but the heavy metal content is higher, so this practice has gradually become less.
The pickling steel industry has developed a hydrochloric acid regeneration process, such as a spray roaster or a fluidized bed hydrochloric acid regeneration process. These processes allow hydrogen chloride gas to be regenerated from the acid wash. The most common of these is the high temperature hydrolysis process.
The hydrogen chloride gas thus obtained is dissolved in water to obtain hydrochloric acid. Through the recovery of spent acid, a closed acid cycle has been established. By-product iron oxide is also used in a variety of industrial processes.
Another major use of hydrochloric acid is in the preparation of organic compounds such as vinyl chloride, dichloroethane, the precursor bisphenol A of polycarbonate, the catalytic adhesive polyvinyl formal, ascorbic acid, and the like. When the company synthesizes PVC, it is usually not commercially available, and internally prepared hydrochloric acid is used. Hydrochloric acid also has great uses in pharmaceuticals.
Hydrochloric acid can react with acids and bases, so many inorganic compounds can be prepared, such as the chemicals required for treating water, ferric chloride and polyaluminum chloride (referred to as polyaluminum, PAC).
Ferric chloride and polyaluminum act as flocculants and coagulants in the production of sewage treatment, paper, drinking water, etc. 
Other inorganic substances can be prepared by using hydrochloric acid, including calcium chloride for road use, nickel chloride for electroplating, zinc chloride for industrial applications and battery manufacturing, and zinc chloride for battery manufacturing. In addition, activated carbon is often prepared from charcoal by a zinc chloride activation process.
Hydrochloric acid can be used to adjust the pH of the solution.
When the purity requirements in the industry are extremely high (such as for food, pharmaceutical and drinking water), high-purity hydrochloric acid is often used to adjust the pH of the water stream; when the requirement is relatively low, industrial pure hydrochloric acid is sufficient to neutralize the wastewater. Or treat the water in the pool. 
For flame reaction
The flame reaction is often used for the inspection of metals or their compounds, and the platinum wire used for inspection is washed with dilute hydrochloric acid to remove the influence of impurity elements.
Before inspecting the substance, the platinum wire should be washed with hydrochloric acid and then placed on a flame to burn until the flame is in the original color.
Regeneration of resin
High quality hydrochloric acid is commonly used for the regeneration of cation exchange resins. Cation exchange is widely used in mineral water production to remove the solution
Plasma, and hydrochloric acid can wash away these ions in the resin after the reaction.
There are also many small-scale uses for hydrochloric acid, such as leather processing, salt production, and in the construction industry . Hydrochloric acid is also commonly used in the petroleum industry: hydrochloric acid is injected into the oil well to dissolve the rock, forming a huge void. This method is often used in the oil extraction industry in the Beihai Oilfield. 
Hydrochloric acid can dissolve calcium carbonate. Applications include descaling or lime mortar used in bricklaying. However, hydrochloric acid is dangerous and should be used with caution. It reacts with calcium carbonate in lime mortar to form calcium chloride, carbon dioxide and water:
Hydrochloric acid is commonly used in the production of gelatin, food, food materials and food additives. Typical examples are aspartame, fructose, citric acid, lysine, acid hydrolyzed vegetable protein and the like. These processes use food grade (very pure) hydrochloric acid.
If you are interested in our products, please contact us.（http://www.bdherb.com/）