Microwave-assisted cleaner extraction of tannin from Terminalia chebula: A promising green method for sustainable leather dyeing

Natural dyes have gained significant attention in recent years due to their environmentally friendly characteristics. This research paper focuses on the dyeing of leather using a natural dye extracted from hulela zard (Terminalia chebula). The objective of this study was to evaluate the efficiency of microwave-assisted extraction in isolating tannin from hulela zard and its subsequent application in leather dyeing. The research involved optimizing various dyeing parameters, such as temperature, time, pH, salt concentration, and extract volume, using a central composite design and response surface methodology. The results showed that microwave treatment significantly improved the extraction yield of tannin from hulela zard, while also enhancing the sorption behavior of leather. Scanning electron microscope (SEM) analysis confirmed the surface modification of leather without affecting its chemical structure. Fourier transform infrared spectroscopy (FTIR) revealed no significant changes in the functional groups of dyed and undyed leather samples, indicating the preservation of the leather's chemical integrity. The colorfastness properties of the dyed leather were evaluated, and it was found that the combination of specific chemical mordants and bio mordants resulted in desirable colorfastness ratings. Overall, this research demonstrates the effectiveness of microwave-assisted extraction for obtaining tannin from hulela zard and its successful application in leather dyeing, offering a sustainable and environmentally friendly alternative to synthetic dyes. [Display omitted] •Leather was dyed using natural dyes.•Bio-mordanting was used as a replace of metal mordanting.•Bio-dyeing of leather shows excellent fastness properties.•Terminalia chebula based natural dye can be an alternative to synthetic dyes.