Sustainable Dyeing of Cotton Fibers Using Aqueous Extract of Citrullus Colocynthis Leaves: Chemical Characterization, and Dyeing Optimization Process Using Response Surface Methodology

Owing to their advantageous characteristics, natural dyes are highly needed to replace hazardous synthetic colored molecules. In this work, an aqueous extract of Citrullus colocynthis leaves was prepared, analyzed using Fourier Transform Infrared (FT-IR) spectroscopy and High-Pressure Liquid Chromatography/Mass Spectrometry (LC-MS/MS), and further used to dye cotton fibers. FT-IR results suggested that the studied Citrullus colocynthis leaf is possibly rich in phenolic and flavonoid constituents. The dyeing experiments were carried out at various experimental conditions: dyeing duration (30-60 min), temperature (60-100 degrees C), and pH (5-9). Response sur-face methodology (RSM), with the help of Minitab 17.1.0, was used to optimize the dyeing process. The optimum obtained dyeing conditions were time = 30 min, temperature = 91 degrees C, and pH = 7. The cationization of cotton fabric with polyethyleneimine and a co-polymer of dimethyl diallyl ammonium chloride and diallylamin, and the pre-biomordanting with pome -granate peel and date palm pits significantly improved the color strength (K/ S) results. Overall, the dyed cotton samples exhibited good fastness characteristics.