Journal of Chemical Technology and Biotechnology, Vol.68, No.2, 151-156, 1997
Enzymatic Desizing of Polyvinyl-Alcohol from Cotton Fabrics
Enzymatic degradation of polyvinyl alcohol (PVA) was used for the desizing of cotton fabrics. A mixture of two different PVA-degrading enzyme activities, including PVA oxidizing, was partially purified from the culture filtrate of a PVA-degrading mixed culture by ionic exchange chromatography. Optimum conditions for PVA-degradation by using this enzyme mixture were pH 8.0 and temperatures ranging from 30 degrees C to 55 degrees C. Cotton fabrics sized with a PVA solution (25 g dm(-3)) were desized with the enzyme mixture after a 1 h treatment at 30 degrees C and pH 8.0. In this case, similar amounts of residual PVA in fabrics were detected in comparison with the conventional desizing process which uses hot water (80 degrees C, 30 min). Minimum amounts of residual PVA were found when the enzymatic desizing time was extended to 6 h. Also, the PVA content in the liquid waste from the enzymatic desizing carried out during 4 h was negligible with a 7.4-fold increase in the biochemical oxygen demand as compared with the initial value.
Keywords:DEGRADING ENZYME;OXIDASE