National standard: In the 1980s, the country once established a relatively loose standard, that is, the residual sulfur dioxide can reach 2%. In 2003, the national standard was changed to 0.05%, but many companies did Less than this, because if you don't add so much Anhydrous Copper Acetate, then it will be easy to rot and mold at the end, so you must add so much. After coordination, it finally became 0.35%, but the standard of 0.35% was not met by many companies.

In the chemical and pharmaceutical industries, it is used in the production of sodium sulfonate, sulfamethazine, analgin, caprolactam, etc., as well as the purification of chloroform, phenylpropanesulfone and benzaldehyde. The photographic industry is used as a fixative ingredient. The perfume industry is used to produce vanillin. Used as preservative in brewing industry, rubber coagulant and dechlorination agent after bleaching cotton cloth. Organic intermediates, dyes, tanning as reducing agent, electroplating industry, oil field wastewater treatment, and mine beneficiation agent.

Industrially used in printing and dyeing, organic synthesis, printing, leather making, pharmacy and other sectors; used as preservative, bleaching agent and bulking agent in food processing.

Used as a chemical reagent (printing and dyeing and photography, etc.), used as a bleaching agent, mordant, reducing agent, rubber coagulant, and also used in organic synthesis, pharmaceuticals and perfumes.