Amine-Functionalized MWCNTs for the Removal of Mordant Black 11 Dye

In this study, amine-functionalized MWC NTs (f-MWCNTs) have been investigated as poten tial material for the removal of Mordant black dye 11 (MBD 11). To evaluate the optimal condition and adsorption capability of the adsorbents (f-MWCNTs), the effect of temperature, pH, adsorbent dosage, and contact time on adsorption rate are examined. The study shows a stronger interaction between the dye and f-MWCNTs. The highest removal efficiency is observed in acidic medium (pH 2) with an initial dye concentration of 50 mg L−1, where 99% of the dye is adsorbed from the medium in 40 min using 0.05 g of f-MWCNTs. Adsorption isotherm and kinetic studies reveal that adsorption occurs by the Langmuir adsorp tion model and pseudo-second-order adsorption kinet ics. According to the thermodynamic parameters, the adsorption exhibits endothermic and spontaneous behavior.