Measurement and Quality of Wool Mordant Effluent

Three mordant concentrations, 7%, 12%, and 17% by the weight of fiber (wof) were examined. The effluent characteristics of chemical oxygen demand (COD) and total organic carbon (TOC) were also measured. ASTM D5673-16 Inductively Coupled Plasma Mass Spectrometry was used to measure the Al ions in the treated liquors and in the substrates. COD and TOC were measured using the COD 8000 method and the TOC analyzer. Both for fabric and yarn, the Al remaining in the substrate decreased with an increase in PAS. The 7% wof PAS concentration was significantly more efficient (p<0.050) compared to the often recommended 12% concentration. This research supports the use of PAS as a mordant for the selected wool substrates when the effluent is neutralized. Further studies could investigate lower concentrations of PAS, the feasibility of reusing the treated liquors, and the impact of PAS amount to dye color parameters.