Caustic soda, also known as sodium hydroxide, is a soluble strong alkali. Caustic soda is easily soluble in water and is strongly alkaline, so it is usually used in the chemical industry. Of course, it is often seen in life.
Uses of caustic soda
1. Ordinary soap is the sodium salt of higher fatty acid, which is generally prepared by saponification of oil under the action of a slight excess of caustic soda.
2. In the printing and dyeing and textile industries, a large amount of lye should be used to remove the grease on cotton yarn, wool, etc. The production of man-made fibers also requires caustic soda.
3. Caustic soda is also used for refined petroleum. In order to remove the gum in the petroleum fraction, concentrated sulfuric acid is generally added to the petroleum fraction so that the gum becomes an acid residue and separates out. After pickling, the petroleum also contains acidic impurities such as phenol, naphthenic acid and excess sulfuric acid, which must be washed with caustic soda solution and then washed with water to obtain refined petroleum products.
4. In the paper industry, chemical treatment is first required, and the raw materials containing cellulose and chemical agents are cooked into pulp. The so-called alkaline pulping is to use the caustic soda solution as the cooking liquid to remove the lignin, carbohydrates and resins in the raw materials, and neutralize the organic acids, so as to separate the cellulose.
5. In the metallurgical industry, the active ingredients in the ore are often converted into soluble sodium salts in order to remove insoluble impurities. Therefore, it is often necessary to add caustic soda.
6. In the chemical industry, caustic soda is used in the production of metallic sodium and electrolyzed water. The production of many inorganic salts, especially the preparation of some sodium salts, requires caustic soda. Caustic soda is also used in the synthesis of dyes, pharmaceuticals and organic intermediates.
7. Unblock the sewer and clean the range hood. Caustic soda is a strong base that decomposes proteins. Pipeline blockage Decomposition of blocked hair under the action of caustic soda is corroded, and the pipeline is unblocked.
Precautions
Caustic soda has the effect of decomposing protein. Be careful when using it, especially not to get it into your eyes and hands. If it is splashed, you should immediately rinse it with plenty of water until there is no greasy feeling. Also be careful out of the reach of children. Caustic soda does not react to metals except aluminum. It has no effect on pipes such as cement, both of which are alkaline.
