Environmentally Friendly Dyeing of Wool, Cotton and Soybean Fibers by Using Apple (Malus Domestica), Linden Tea (Tilia Tomentosa) and Mate Tea (Ilex paraguariensis plant) plant wastes as a Natural Dye Source

Abstract The growing focus on sustainable coloration strategies has prompted the investigation of agro-industrial by-products as potential dye sources for textiles. In this study, wool, soybean, and cotton fibers were dyed using liquid dye solutions obtained from the extraction of waste materials generated during the production of apple (Malus domestica), linden tea (Tilia tomentosa), and mate tea (Ilex paraguariensis). The color development observed on the textile samples was significantly contributed to by the polyphenolic structures identified in the extracts, as confirmed by high-performance liquid chromatography (HPLC) and ultraviolet–visible (UV–Vis) spectroscopy analyses. Sodium carbonate (Na₂CO₃) and citric acid (C₆H₈O₇) were used to modify the surface charge characteristics of the textile substrates, and ferrous sulfate (FeSO₄), sodium alginate (C₆H₇NaO₆), calcium carbonate (CaCO₃), alum (Al₂(SO₄)₃), potassium sodium tartrate (KNaC₄H₄O₆), aluminum chloride (AlCl₃) and magnesium chloride (MgCl₂) were employed as mordants during the dyeing process. Optimal extraction and dyeing durations, as well as appropriate mordant concentrations, were systematically investigated. Colorimetric evaluations (CIE L * a * b * coordinates) and colorfastness tests, including washing, crocking, perspiration and saliva fastness, were conducted according to standard protocols. The highest fastness ratings (grade 5) for washing, crocking and perspiration were obtained for wool, cationized cotton and soybean fibers dyed with colorants extracted from linden (Tilia tomentosa) waste. In contrast, samples dyed with extracts derived from apple and mate tea waste showed fastness values ranging from 5 to 3–4. Following the dyeing process, the metal content of the wastewater from the mordanting process was quantified using Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES). The environmental implications of the detected metal concentrations were subsequently assessed.