Hexadecyl Trimethyl Ammonium Bromide-Modified Montmorillonite as a Low-Cost Sorbent for the Removal of Methyl Red from Liquid-Medium

In this study, montmorillonite (MMT) modified by a cationic surfactant (Hexadecyltrimethyl ammonium bromide, HDTMA) was used as adsorbent to the removal of methyl red (MR) from aqueous solution. The effect of different parameters includes surfactant loading rate, contact time, pH, adsorbent dosage, and initial MR content was investigated on the sorption. The sorption capacity was increased by increasing the surfactants loading rate up to 120% cation exchange capacity (CEC) of the clay. The contact time 30 min and pH of 6 were selected as the optimum for the uptake of MR. The maximum uptake capacity was obtained 1428.5 mg/g. The experimental data of the sorption was well fitted by pseudo-second-order kinetic and Freundlich isotherm models. The results show that the HDTMA-modified MMT can be applied as an effective and low cost sorbent for the removal of MR dye from aqueous solution.