Synthesis and Characteristics of Copper-complex Catalyst for low temperature bleaching of H2O2

Abstract

In order to solve the problems of high energy consumption and fabric damage caused by conventional high-temperature bleaching, three copper complex catalysts were synthesized for low-temperature bleaching of cotton fabrics through the coordination reaction of copper with organic ligands. The three copper complex catalysts synthesized have polar proton groups that are soluble in water. Copper complex catalysts are metal-organic catalysts that can be cleaned with only a small amount of water and can be used for fabric bleaching. Characterization of three copper complex catalysts by elemental analysis and infrared spectroscopy. Copper sulfate was used as a reference to study the efficiency of catalytic hydrogen peroxide decomposition by copper sulfate complex catalyst at 70℃. The effect of temperature, time, penetrant and catalyst concentration on the whiteness of cotton fabrics bleached with hydrogen peroxide was evaluated by bleaching experiments. And an optimized bleaching method was designed for the copper complex catalyst. Compared with conventional high-temperature bleaching, it can reduce the bleaching time to 40 minutes at 95℃ while maintaining high whiteness. The results showed that: the use of copper complex catalyst could decompose hydrogen peroxide at low-temperature; The use of copper complex catalyst could improve the whiteness of cotton fabric and reduce the time of high-temperature bleaching; The penetrant could significantly improve the whiteness of hydrogen peroxide bleaching; The optimized bleaching method was 40 minutes bleaching at 70℃ and 20 minutes bleaching at 95℃; The whiteness of the cotton fabric was 80.84% when catalyst 2 was added and bleached using the optimized bleaching method. This exceeded the whiteness of traditional high-temperature bleaching with the commercially available catalyst Bleach Ace.