The Study Of Gas Phase Method Of Fabric Pretreatment Process

China is the main producers of textiles. Most textiles need to be bleached. Traditional bleaching process has a large wastewater emission and the wastewater contains a lot of toxic substances. It makes a tremendous threat to human body health. Therefore, research on lower energy consumption, lower pollution of new bleaching process is of great significance. This article first use hydroxyl free radical active oxygen reagents to prepare chlorine dioxide. Chlorine dioxide is of high purity and high yield. Use the product to bleach cotton fiber. It changes the traditional bleaching way with high temperature liquid. This way not only reduces the energy consumption, but also solves the problem of large amount of bleaching wastewater and high content of pollutants.The preparation of chlorine dioxide using hydroxyl radicals active oxygen agent is a new method of preparation of chlorine dioxide. The purity and yield of chlorine dioxide is measured by the method of continuous iodine quantity. On the basis of single factor experiment, use orthogonal experiment to determine the best condition of active oxygen preparation of chlorine dioxide. Use gaseous chlorine dioxide to bleach cotton textile. Test strength and whiteness of the fabric before and after bleaching with the whiteness meter and powerful machine. Using SEM, XRD diffraction and FRIT analysis the cotton fiber microscopic changes before and after bleaching Compare the pros and cons of the hydrogen peroxide bleaching process and chlorine dioxide bleaching process. This article has also designed the device for the method of gaseous chlorine dioxide bleaching. The material selection and structure design are discussed.The best generation conditions were as follows:the concentration of sodium hypochlorite was 400g/L, the molar ratio of active oxygen to sodium hypochlorite was 0.5:1, the concentration of sulfuric acid was 4.5mol/L, the reaction temperature was 55℃.The purity of chlorine dioxide is about 91% and the yield of chlorine dioxide is about 94%.The best condition of gas phase method of bleached cotton fabric is as follow:the bleaching temperature is 25 ℃, chlorine dioxide concentration is 7.5%, bleaching time is 2 hours. Under these conditions, whiteness can be maintained at 84%, strength loss can be stable at 7.26%. By SEM, XRD diffraction and FTIR analysis shows that in the process of bleaching lignin and impurity has been removed and the cotton fiber itself has not been changed. New bleaching process has not only low energy consumption, less waste water but also the damage of the fiber is much smaller than the traditional process.Ascertain the main material of the device is PVC sheet and high borosilicate glass. The rollers and water seal device of bleaching equipment makes the equipment with the characteristics of corrosion resistance to chlorine dioxide, continuous production and the gas seal.