A group of gemini cationic surfactants containing three hydrophobic and two hydrophilic groups was used as the spacer to modify sodium montmorillonite (MMT-Na) via cation exchange to produce an p-chlorophenol removal. The gemini cationic MMT-Na was characterized with FT-IR and XRD, and its thermal stability was analyzed using thermogravimetric analysis (TG).
The modified montmorillonites performed a good removal of p-chlorophenol in wastewater. The p-chlorophenol adsorption amount of the gemini cationic MMT-Na is up to 39.36 mg/g, which is 6 times higher than that of MMT-Na. The modified montmorillonites also present a good thermal stability and the decomposition happened at 200-500°C mainly due to initial weight loss from residual water desorption, followed by decomposition of the surfactant and the dehydroxylation of structural water in the montmorillonite layers. The structure-function relationship of the surfactant was also investigated.
