Design of Chitosan-Polyester Composites to Reduce Particulate Contamination of Washing Wastewater

Abstract

In this research, the modification of different polyester structures (fabrics and knits) by the biopolymer chitosan was studied to evaluate the effects of the polyester structure and treatments on the particulate pollution of wastewater. The pristine polyester and the chitosan-polyester fabric and polyester knit composites were washed cyclically with standard ECE A detergent at 60 °C. The laser diffraction technique was used to characterize the particle size of the washing wastewaters from the 1–5, 6–10 and 1–10 wash cycles. In addition, the total solids (TS), total suspended solids (TSS), total dissolved solids (TDS), turbidity and chemical oxygen demand (COD) were also determined, according to standard procedures. The obtained results show the influence of the polyester fabrics and polyester knit structures and chitosan-polyester composites on the particle size distribution (PSD) in the washing wastewater. Differences in the values of the characteristic parameters, especially the span value and shape factor (k) of the individual curves, are visible, indicating the release of particles during the washing process. The experimental results show that the laser diffraction technique is suitable for characterizing the particle dimensions of the washing wastewater for different pristine polyester structures and chitosan-polyester composites. Modification with chitosan has been shown to provide potential protection against the release of microplastic particles into the environment.