The principle of sulfur dioxide urea as a bleaching and decolorizing agent is as follows:

1. Oxidizing property of sulfur dioxide (SO₂): Sulfur dioxide is a gas with strong oxidizing properties. It can react with various substances. During the bleaching process, sulfur dioxide can oxidize certain compounds in the colored material, causing them to lose color.

2. Reducing property of urea: Urea is a compound with reducing properties. Under certain conditions, it can undergo a reduction reaction, converting oxidized compounds in the colored material into colorless or lighter compounds. The reducing property of urea combines with the oxidizing property of sulfur dioxide to achieve the bleaching and decolorizing effect.

In practical applications, sulfur dioxide urea is commonly used in the bleaching of pulp, textiles, food, cosmetics, and other industries. The working principle can be summarized as follows:

1. Reaction of sulfur dioxide urea with water to produce sulfurous acid: When sulfur dioxide urea dissolves in water, it reacts with water molecules, producing sulfurous acid (H₂SO₃) and urea enzyme. Sulfurous acid is a weak oxidizing agent that can react with certain compounds in the colored material.

SO₂-urea + H₂O → H₂SO₃ + Urea enzyme

2. Oxidation of colored compounds by sulfurous acid: Sulfurous acid oxidizes certain compounds in the colored material, causing structural changes and color loss. Sulfurous acid is reduced to sulfuric acid during the oxidation process.

H₂SO₃ + Colored compound → Oxidized products + H₂SO₄

3. Reducing action of urea: Urea, as a reducing agent, participates in the reaction, reducing oxidized compounds in the colored material into colorless or lighter compounds.

Urea + Oxidized products → Reduced or lighter-colored products

Through the action of sulfur dioxide urea, certain compounds in the colored material are oxidized or reduced, resulting in bleaching and decolorization. It is important to control the dosage and reaction conditions of sulfur dioxide urea during application to achieve the desired bleaching effect while avoiding potential harm to the environment and human health.

Buske New Material Technology (Shandong) Co., Ltd specializes in the professional production of sulfur dioxide urea. Welcome to inquire. 

Email: buske@buskesd.com,

Phone: +86 0546-8270002.