Product Details
Hydrochloric acid is an aqueous solution of hydrogen chloride (HCl) and is widely used in various industrial applications. It is a clear, colorless to pale yellow liquid with a strong, pungent odor and highly corrosive properties. A 38% hydrochloric acid solution has a melting point of -27.32°C and a boiling point of approximately 48°C.
Concentrated hydrochloric acid, typically containing around 37% hydrogen chloride by mass, is highly volatile. When a container of concentrated hydrochloric acid is opened, hydrogen chloride gas readily evaporates into the surrounding air.
Hydrochloric acid has numerous important applications in the chemical industry and plays a significant role in maintaining product quality. It is commonly used for steel pickling and serves as an essential chemical reagent in the large-scale production of many inorganic and organic compounds, including vinyl chloride, a key precursor for PVC plastics.
Hydrochloric acid also has a variety of smaller-scale applications, such as household cleaning, the production of gelatin and other food additives, descaling formulations, and leather processing. In addition, hydrochloric acid is a major component of gastric acid, where it helps promote digestion and provides protection against microbial infections.
Key Physical & Chemical Properties
| Property | Specification |
|---|---|
| Chemical Formula | HCl (aqueous solution) |
| Appearance | Clear to pale-yellow fuming liquid |
| Concentration | 31% / 36% / 37% (typical) |
| Boiling Point | ~48 °C (azeotrope at 20.2%) |
| Acidity | Strong mineral acid |
| Corrosivity | Highly corrosive to metals and skin |
| Grades | Industrial / food / reagent grade |
Applications
Metal Treatment: Pickling / descaling of steel and metals; surface preparation before coating.
Water Treatment: pH adjustment, alkalinity control, and regenerant for ion-exchange resins.
Chemical Synthesis: Raw material for chlorides, fertilizers, and various organic/inorganic compounds.
Cleaning & Descaling: Removal of scale, rust, and mineral deposits in boilers and equipment.
Food & Pharmaceutical: Acidulant and processing aid (food grade) in limited applications.
Laboratory Reagent: Standard acid for analysis and pH control.
