Hydrosulfite is widely used in reductive dyeing, reductive cleaning, printing and decolorization in the textile industry and for bleaching of silk, wool, nylon and other fabrics. Because it does not contain heavy metals, the bleached fabrics are bright in color and not easy to fade. In terms of various substances, hydrosulfite can also be used for food bleaching, such as gelatin, sucrose, honey, etc., soap, animal (vegetable) oil, bamboo, and porcelain clay.
Hydrosulfite can also be used in organic synthesis, such as reducing agent or bleaching agent in the production of dyes and pharmaceuticals. It is the most suitable bleaching agent for wood pulp and papermaking. Moreover, many heavy metal ions such as Pb2+ and Bi3+ can be reduced to metals in water treatment and pollution control, and can also be used to preserve food and fruits.
However, due to the many dangers of hydrosulfite, many of its uses tend to be replaced by thiourea dioxide, which is safer and easier to store and transport.
1. Low sodium sulfite has stronger reducibility than general sulfites, and has the strongest reducing and bleaching properties among sulfite bleaching agents. my country stipulates that it can be used for candied fruit, glucose, sugar, rock sugar, caramel, candy, liquid glucose, dried fruit, dried vegetables, vermicelli, bamboo shoots, mushrooms and canned mushrooms, with a maximum usage of 0.40g/kg.
Residual amount of potato starch (calculated by SO2)≤0.05gkg. Strong reducing agent, can reduce many metal salts into metals. Analysis of nitrogen fertilizer, ammonia water and ammonium bicarbonate desulfurization liquid. Polarographic visualization. bleach.
2. Widely used in printing and dyeing industry, such as cotton fabric dyeing auxiliaries and bleaching of silk and wool fabrics. Also used in medicine, mineral processing, copperplate printing. The paper industry is used as a bleaching agent, etc. Food grade products are used as bleaches, preservatives and antioxidants.
3. In light industry, it is used for bleaching soap, oil ester and pulp. The chemical industry is used in the manufacture of white powder, sodium thiosulfate, thiourea, thiobenzoic acid, hexaoxalic acid (medicine), synthetic dyes, and also used in copperplate printing and analytical reagents.
4. In the printing and dyeing industry, it is used as a reducing agent, a bleaching agent for silk and wool, and is also used in the pharmaceutical industry, mineral processing, and the synthesis of thiourea and its sulfides.
Sulfonite is a white fine-grained powder, sometimes with a yellow or gray tinge. Has a special odor and strong reducing properties. Compared with the oxidizing agent, the damage to the clothing is much smaller, so it is called the insurance powder. It can be used in textiles of various fibers without causing harm.
