Evaluation of Dyeing Characteristics of Cotton with Vat Dyes Using Alkaline Lipase and Fe (II) Salt

Application of sodium hydrosulfite along with NaOH successfully reduces and solubilizes all vat dyes at specific temperature. However, being a highly toxic chemical, use of hydrosulfite has raised tremendous ecological concern. In this study, attempts were made to dye cotton with alkaline lipase along with iron (II) salt to study if unstable and highly toxic sodium hydrosulfite could be replaced with it. A 43 Box-Behnken design was run for statistical analysis to obtain optimum parameters for dyeing of cotton using alkaline lipase. The results showed that alkaline lipase along with iron (II) salt was Quite effective and capable of developing comparable dyebath potential, dye receptivity on cotton with comparable dye strength and color fastness as obtained in sodium hydrosulfite based reducing system.