Hydrophobic deep eutectic solvents on removal of dyes from wastewater

In this study, deep eutectic solvents of tetrabutylammonium bromide with glycerol, tetrabutylammonium bromide with decanoic acid, and tetrabutylammonium bromide with oleic acid at 1: 2 ratios were prepared and characterized by FT-IR spectroscopy. Subsequently, the functional group of naphthol green B, malachite green, acid blue 80, and acid red 1 dye are analyzed through FT-IR spectroscopy. It was observed that tetrabutylammonium bromide with glycerol forms a homogeneous phase with the dye solution, making it unsuitable for the extraction process. Conversely, tetrabutylammonium bromide with decanoic acid and tetrabutylammonium bromide with oleic acid were identified as potential solvents for the extraction of naphthol green B, malachite green, acid blue 80, acid red 1dyes from their solution. This extraction mechanism between deep eutectic solvent and dyes was analyzed through FT-IR spectroscopy focusing on H-bond formation, and metal coordination upon mixing.