A novel cotton bio-scouring using pectinase in combination with Fenton system

Abstract

Untreated cotton fabrics are hydrophobic due to the high content of pectin and waxes, and the fabrics need to improve the wettability by scouring for the demands of the subsequent processing such as dyeing and finishing. In this study, a new scouring method for cotton fabrics was developed by pectin hydrolase combined with Fenton system (Fe²⁺/H₂O₂). The mechanism of pectin degradation by pectinase combined with Fe²⁺/H₂O₂ was investigated. The results showed that α-1,4-glycosidic bonds of water-soluble pectin could be degraded more efficiently by pectinase hydrolysis and Fe²⁺/H₂O₂ oxidation. The fabrics scoured with pectinase→Fe²⁺/H₂O₂ had less wetting time (4.25 s) and higher vertical wicking height (9.80 cm) compared to the fabrics treated with pectinase alone (> 120 s, 5.15 cm). The results of bleaching and dyeing experiments indicated that the whiteness and dyeing properties of the fabrics were not negatively affected by pectinase→Fe²⁺/H₂O₂ treatment, and the strength loss of the fabrics (11.79%) was lower than that of the fabrics with conventional NaOH treatment (20.16%). The results of the experiments in the pilot-scale machine showed that various performance indicators of the fabrics scoured by pectinase→Fe²⁺/H₂O₂ reached the level of the conventional NaOH treatment, which demonstrated the possibility for practical application of pectinase→Fe²⁺/H₂O₂ scouring. The cotton fabric scouring using pectinase→Fe²⁺/H₂O₂ is an effective and feasible new method with advantages such as environmental friendliness, mild treatment conditions, and good treatment effect.