Rapid modification of montmorillonite with novel cationic Gemini surfactants and its adsorption for methyl orange

A rapid method was developed to prepare organic montmorillonite (organo-MMT) using three novel Gemini surfactants by microwave irradiation of 1 h, which was more effective than conventional heating method of 8–48 h. The structure and morphology of organo-MMTs were characterized by XRD, FT-IR, TEM and SEM. The adsorption amount of Gemini surfactants on MMT and the thermal stability of organo-MMTs were investigated by thermogravimetric analysis (TGA). The results indicated that Gemini surfactants were more efficient than cetyltrimethyl ammonium bromide in the modification of MMT, the organoclays obtained by microwave irradiation method had larger layer spacing than those from traditional heating method. And with the increase of the dosage and chain length of Gemini surfactants, the amount of the intercalary or adsorbed surfactant on the organoclay gradually increased, whereas the thermal stability weakened appropriately. Besides, the adsorption results for methyl orange indicated that all organo-MMTs displayed more excellent adsorption capacities than unmodified MMT. The amount of methyl orange adsorbed onto the organo-MMTs increased proportionately with the increase of the amount or the chain length of Gemini surfactants. This study affords a rapid and efficient method to obtain the organoclay with large interlayer distance and strong adsorption capacity.

A rapid method was developed to prepare organic montmorillonite (organo-MMT) using three novel Gemini surfactant by microwave irradiation of 1 h, which was more effective than conventional heating method of 8–48 h. The results showed that as the dosage and chain length of Gemini surfactants increased, the amount of the intercalary or adsorbed surfactant on the organoclay gradually increased, and the amount of methyl orange adsorbed onto the organo-MMTs also enhanced.Figure optionsDownload as PowerPoint slideHighlights
► Rapid modifications of montmorillonite with Gemini surfactants were performed for 1 h.
► The amount of the surfactant on organoclay was examined by thermogravimetric analysis.
► Surfactant amount on the organoclay increased with increasing chain length and dosage.
► All organoclays displayed more excellent adsorption capacities on dye than clay.
► The adsorption capacity was positive to the amount and chain length of the surfactant.