What is sulfuric acid

Speaking of sulfuric acid, many people will actually feel fear. In fact, it is widely used in life, especially high-concentration sulfuric acid, which has strong water absorption. It is generally used as a dehydrating agent, to carbonize wood, paper or medicine, explosives, raw materials, detergents, etc. Let us take a closer look at its applications in industry and life.

1. Overview

Sulfuric acid is one of the most active binary inorganic strong acids and can react with many metals. High concentration of sulfuric acid has strong water absorption capacity and can be used as a dehydrating agent to carbonize carbohydrate-containing materials such as wood, paper, cotton and linen fabrics, and biological skins and flesh. When mixed with water, it also releases a large amount of heat energy. It is highly corrosive and oxidizing, so use with caution. It is an important industrial raw material that can be used to make fertilizers, medicines, explosives, pigments, detergents, batteries, etc. It is also widely used in industries such as petroleum purification, metal smelting, and dyes. It is often used as a chemical reagent and can be used as a dehydrating agent and sulfonating agent in organic synthesis. Colorless viscous liquid, highly corrosive, with a pungent odor, easily soluble in water, generating dilute sulfuric acid.

2. Metallurgy and Petroleum Industry

Used in metallurgy and metal processing In the metallurgical industry, especially the production process of non-ferrous metals requires the use of sulfuric acid. For example, when refining copper, zinc, cadmium, and nickel by electrolysis, sulfuric acid is needed as the electrolyte. The refining of certain precious metals also requires sulfuric acid to dissolve other metals that are included. Before cold rolling, cold drawing and stamping in the steel industry, sulfuric acid must be used to remove iron oxide from the steel surface. When rolling thin plates, cold-drawn seamless steel pipes and other steel products with higher quality requirements, they must be washed with sulfuric acid every time they are rolled. In addition, seamed steel pipes, thin iron sheets, iron wires, etc. must be pickled with sulfuric acid before galvanizing. In some metal machining processes, such as nickel plating, chrome plating and other metal parts, sulfuric acid is also needed to clean the rust on the surface. In the ferrous metallurgical enterprise sector, steel that needs pickling generally accounts for about 5% to 6% of the total steel output, and the pickling of each ton of steel consumes about 30 to 50 kg of 98% sulfuric acid.

III. Strengthening National Defense

The development of the sulfuric acid industry in some countries was once closely linked to the production of military explosives. Whether military explosives (propellants, blasting powder) or industrial explosives, most of them are composed of nitro compounds or nitrate esters as their main ingredients. The main ones are nitrocellulose, trinitrotoluene (TNT), nitroglycerin, picric acid, etc. Although the preparation of these compounds relies on nitric acid, concentrated sulfuric acid or oleum must also be used.