Catalytic activation of peracetic acid using chitosan-metal complex for low-temperature bleaching of cotton fabric

摘要

A novel approach for bleaching of cotton fabric has been used and the most appropriate conditions for bleaching established. The technique adopted is based on the utilization of tetraacetylethylenediamine (TAED) along with hydrogen peroxide (H_2O_2) where in-situ peracetic acid (PAA) formation takes place via reaction of TAED and H_2O_2. Decomposition of the so created PAA to enhance its bleaching effect has been induced by using chitosan-Mo complex or chitosan-Co complex as a catalyst. Regulation of the reaction of H_2O_2 with TAED has been achieved using sodium silicate whereas the regulation of the decomposition of PAA and, therefore, its bleaching action has been achieved using sodium lauryl sulphate (SLS). Replacement of H_2O_2 with other oxidizing agents, namely ammonium persulphate and potassium bromate, was not successful. In contrast, the perborate did succeed but with lower efficiency when compared with H_2O_2.