Recognizing a limitation of the TBLC-activated peroxide system on low-temperature cotton bleaching

•Cotton could be bleached at low temperatures with the TBLC-activated peroxide system in rapid exhaustion process.•The low-temperature bleaching performance was unexpectedly diminished with a high TBLC concentration.•The TBLC-activated peroxide system had a limitation on cotton bleaching in cold pad-batch process.•Such a limitation may be caused by the adsorptive interaction of TBLC and the in situ formed compounds with cotton fibers.

In this study, cotton was bleached at low temperatures with an activated peroxide system which was established by incorporating a bleach activator, namely, N-[4-(triethylammoniomethyl)benzoyl]caprolactam chloride (TBCC) into an aqueous solution of hydrogen peroxide (H2O2). Experimental results showed that the bleaching performance was unexpectedly diminished as the TBCC concentration was increased over the range of 25–100 g/L. Kinetic adsorption experiment indicated that this was most likely ascribed to the adsorptive interactions of TBCC and the in situ-generated compounds with cotton fibers. Such a limitation was especially fatal to cold pad-batch bleaching process of cotton in which a high TBCC concentration was often required. The results of this study may stimulate further research to avoid or overcome the limitation of the TBCC-activated peroxide system on low-temperature cotton bleaching.