In the hydrogen peroxide bleaching process, due to the characteristics of low price and excellent effect, sodium silicate was initially widely used as hydrogen peroxide bleaching stabilizer, but it is easy to produce silicon scale on the equipment. Later, people developed organic (non silicon) stabilizers, such as organic carboxylates and fatty carboxylic acids, which is a leap in the development of hydrogen peroxide bleaching technology. Subsequently, peracetic acid bleaching produced by the reaction of hydrogen peroxide with acetic acid or acetic anhydride has also been popularized and applied. Now, hydrogen peroxide bleaching activator and catalyst are introduced into hydrogen peroxide bleaching solution to establish a new and effective bleaching system, which has the characteristics of high efficiency, low consumption, time saving and environmental friendliness.
Hydrogen peroxide bleaching activator is a compound that reacts with peroxide anion (Hoo ‘) in alkaline hydrogen peroxide solution to form peroxy acid. Peroxy acid is a stronger oxidant than hydrogen peroxide. It has stronger bleaching effect and can solve some problems that are difficult to overcome in hydrogen peroxide bleaching. Adding peroxycompound activator to hydrogen peroxide bleaching solution to directly generate peroxyacid in the bleaching solution not only overcomes many defects of preparing peroxyacid in advance, but also increases the types of peroxyacid, such as peracetic acid, peranoic acid, etc.
In the process of establishing a new activated hydrogen peroxide bleaching system, the development of peroxide activator is conducive to the development of hydrogen peroxide bleaching process in the direction of short process, low energy consumption and high efficiency, which is undoubtedly of great benefit to promote the optimization and progress of hydrogen peroxide bleaching process.
Metal complex catalysts have high activity at low temperature, which can promote the decomposition of hydrogen peroxide and improve the bleaching efficiency. At present, metal complexes used in bleaching have similar characteristics to biological enzymes. Biological enzyme has the advantages of high efficiency, mild and specificity, but it is restricted by its limited source and difficult preparation its application is introduced. In the fields of pulp bleaching and environmental purification, the application of metal imitation enzyme system has made some progress, but its application in cotton fabric bleaching needs further research.
