Enzymatic desizing, bioscouring and enzymatic bleaching of cotton fabric with glucose oxidase

The sized cotton fabric was enzymatically desized, scoured and bleached with an enzyme mixture of starch degrading enzymes, pectinases and glucose oxidases (GOxs) was added to generate hydrogen peroxide (HP). In this study, enzyme selection and process optimisation was made in order to increase the glucose content of the desizing liquor of a starch-sized cotton fabric. The highest glucose concentration of 4175 mg/L was measured in one-bath containing mixture of alpha-amylase, amyloglucosidase and pectinase and GOx produced 758 mg/L peroxide. This combination was used in further bleaching processes. For bleaching, hydrogen peroxide was converted into peracetic acid (PAA) by incorporating the bleach activator tetraacetylethylenediamine (TAED). Whiteness values, water absorbency, polymerization degree and tenacity at maximum load were measured on pre-treated samples. The total organic carbon (TOC), chemical oxygen demand (COD), biological oxygen demand (BOD5), the biological degradability (BOD5/COD) and the final pH values were measured on residual pre-treatment baths.