Synthesis Of Macrocyclic Polyamines Mimetic Enzyme Catalyst And Analysis Of Their Catalytic Activity In Bleaching Cotton Fabric Using H₂O₂ As Oxidant

The rapid development of textile finishing industry has brought resource consumption and pollution so that the pressure of energy saving and environmental protection becomes serious. The waste water produced by pre-treatment of cotton fabrics occupies a large proportion of waste water in dyeing and finishing. Bleaching process is an important procedure that consumes energy and water in the cotton fabric pre-treatment. Traditional high temperature and high alkaline hydrogen peroxide bleaching process with high energy consumption is not conducive to environmental protection. So it is important to develop a new hydrogen peroxide bleaching process with low temperature.Some attempts have been made to investigate new compounds as activator for H2O2 bleaching in order to reduce bleaching temperature. However, some of these activators are not soluble in water; some only take effect in 40℃and lose their activities in higher temperature. These limit their applications in cotton fabric bleaching which must remove some impurities at about 80℃. It is necessary to look for a new activator of hydrogen peroxide.Enzyme catalysis is an effective way. Biomimetic catalyst has characteristics of both enzymatic catalyst and chemical catalyst. Therefore, it is an efficient approach of bleaching cotton fabric with mimic enzyme. In this thesis, we studied the activation of the metal complexes of macrocyclic polyamines to H2O2 bleaching process of cotton fabric. Including the study of application these metal complexes catalyzed for the hydrogen peroxide bleaching process.In this paper, four novel metal complexes have been synthesized by the reaction of metal salts [iron(Ⅲ), copper(Ⅱ), cobalt(Ⅱ), ferrous(Ⅱ)] with the ligand, Me3tacn (Me3tacn=N, N, N-trimethyl-1,4,7-triazacyclononane). The resulting product was fully characterized by Elemental analyses, IR spectroscopy and Thermal analysis and single crystal X-ray analysis, in order to determine the structure of the complexes. In addition, the titration method of potassium permanganate was used to discuss the effects of temperature, pH, and the concentration of these complexes on the catalytic decomposition of hydrogen peroxide. In the part of application experiment, these new complexes were used in three 3 different bleaching processes respectively. The effects of temperature, the concentration of these complexes and the concentration of stabilizer on the bleaching of cotton fabric were studied in detail. Finally find the optimization process of bleaching cotton fabric with these metal complexes used hydrogen peroxide as the oxidant.The warm pad-batch bleaching process of cotton fabric is the best application process in three different processes. Metal complexes of copper(Ⅱ) and cobalt(Ⅱ) with trimethyl triazacyclononane respectively played a positive part in bleaching cotton fabric with H2O2, the bleached cotton fabric were given a higher whiteness indexes, accompanied little decrease in breaking strength of the fabric. The application of these new bleaching activators generated a lower bleaching temperature and pH value to some extent compared to the traditional high temperature and high alkaline hydrogen peroxide bleaching process. This process saved energy and protected the environment obviously.