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PVA degrading enzyme good biodegradability of PVA, and PVA desizing process can be applied in the textile industry, the surface of the fabric directly to the degradation of the PVA, thereby reducing emission of dyeing wastewater PVA. The main subject of research PVA-degrading enzyme fermentation, PVA degradation of the enzymatic properties, PVA-degrading enzymes in pure PVA the analog sizing cotton and polyester fabric desizing process, ultrasonic PVA-degrading enzyme mimic desizing other aspects, expect to the PVA slurry biodegradation desizing while desizing wastewater biodegradability. PVA-degrading enzyme fermentation process and the appropriate reaction conditions. PVA degradation the enzyme activity 1.973U/mL. PVA content reduced by 5g / L before the fermentation to 0.1356g / L PVA consumption rate of 97.29%. Certain time, pH, temperature, and concentration of PVA PVA-degrading enzyme activity and degradation rate. Obtained by experiment, PVA degrading enzyme suitable reaction conditions: pH = 7.0-8.0, T = 30 ℃. PVA concentration of 1g / L, the reaction is 3H, the PVA degradation rate of 49.32%. In this paper, PVA-degrading enzyme applied to the PVA analog sizing cotton fabric desizing process. PVA-degrading enzyme desizing, desizing of PVA When desizing 2h, 35.78%, the the PVA amount of residue on the cloth to 43.53%, desizing rate of 56.47%, while the effect to reach the hot water desizing , but PVA slurry in the the PVA amount of cotton fabric remaining on the amount of and less than 100%, indicating that while PVA degrading enzyme during desizing sent PVA partial degradation. PVA-degrading enzyme applied to the PVA analog sizing polyester-cotton fabric desizing process, while the introduction of ultrasound technology to assist the PVA-degrading enzyme desizing. The experimental findings, PVA degrading enzyme of PVA analog sizing polyester cotton fabric optimum treatment conditions: pH = 7.5-8.0 phosphate buffer at a volume ratio of 1:1 mixture of the PVA degradation enzyme solution 7mL, 30g / L of sodium chloride 2mL, the temperature of 30 ℃, desizing time was 1.5h, desizing rate of 41.06%, PVA degradation rate was 55.87%; ultrasonic-assisted PVA-degrading enzymes for PVA analog sizing polyester-cotton fabric desizing process , conducive to the PVA-degrading enzyme desizing, its suitability desizing conditions: ultrasonic processing power of 50%, treatment temperature 30 ° C, the treatment time was 45min amount of the enzyme solution, the PVA degradation 7mL, 30g / L of sodium chloride, 2ml desizing rate can reach 38.12%, the PVA degradation rate of 38.85%. Using enzyme pretreatment ultrasonic degradation of PVA, PVA-degrading enzyme activity of the enzyme was measured before and after treatment, in order to examine the ultrasonic power, temperature, ultrasonic time of PVA degradation enzyme activity of the ultrasonic assisted PVA degradation enzyme polyester cotton The desizing effects make the analysis. Experimental results show that the introduction of the ultrasonic wave reduces the PVA-degrading enzymatic activity, and with the increase in the ultrasonic power, temperature, treatment time, PVA decline faster the degradation of the enzyme activity. PVA solution using ultrasonic treatment, ultrasonic treatment PVA molecular size smaller. Compare different desizing of PVA analog sizing polyester-cotton fabric desizing effect found by Fenton oxidant desizing, the fabric weight loss rate is higher, BOD / COD value of desizing, desizing wastewater biodegradability increase, but because of Fenton's reagent role under acidic conditions, damage to the fabric, the fabric tensile strength, low capillary effect, the whiteness is also poor; desizing effect of hot water with a base is poor, high the desizing wastewater COD value, BOD / COD value is small biodegradability of fabric damage; PVA-degrading enzyme desizing, desizing PVA content is of high value, COD, BOD / COD values, improvement of biodegradability and gross efficiency improvement fabric desizing smaller, less strength loss fabric yellowing degree join ultrasonic fabric processing better.
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