Scouring, oxygen bleaching one-step pretreatment

1. The nature and bleaching principle of hydrogen peroxide

The scientific name of hydrogen peroxide is hydrogen peroxide (H2O2). It is a colorless and odorless liquid with a strong oxidizing ability and a burning sensation on the skin. Especially the concentrated hydrogen peroxide, you should pay attention to safety when using it.

H2O2 is unstable, easily decomposed by light and heat to release oxygen, and even cause an explosion. It is relatively stable under weakly acidic conditions, and its decomposition speed is accelerated in alkaline media. Therefore, hydrogen peroxide should be stored in a dark place under normal temperature and weak acid conditions. Heavy metal ions and dust can catalyze the decomposition of H2O2.

2. Analysis of process conditions affecting H2O2 bleaching

pH value: the optimum pH value is 10-11

Temperature: generally 100～110℃

time

concentration

Oxygen bleach stabilizer

3. Process example

Pretreatment process of pure cotton non-mercerized yarn

Hydrogen peroxide (27.5%) 0.5～5g/L

Caustic soda 2g/L

Oxygen bleach stabilizer 0.5～1g/L

Scouring agent 1g/L

Complexing agent 1g/L

Pretreatment process of pure cotton mercerized yarn

Hydrogen peroxide (27.5%) 1～5g/L

Caustic soda 2～2.5g/L

Oxygen bleach stabilizer 0.8～1.2g/L

Penetrant 1g/L

Complexing agent 0.5g/L