Sorption Behavior Of Phthalic Acid Esters By Expansive Layers Minerals Nanocomposites

In this paper, we have used the minerals with expansion layers and their organic nanocomposites to adsob phthalic esters in aqueous solution. Based on exchangeable and absorption of cation hydration layer in mineral with expansion layer, using the same structure but different alkyl chain length of the series quaternary preparation Cn TA+/montmorillonite nanocomposites and Cn TA+/vermiculite nanocomposites with hydrolysis- intercalation compound method to adsorb four phthalate esters in water solution. The Cn TA+/montmorillonite and vermiculite nanocomposites were characterized by XRD, FT-IR and other analytical testing methods and physical performance test. Investigated the impact effect of phthalate esters with adsorption reaction time, initial p H and reaction temperature on adsorption, and explored the quaternary ammonium alkyl carbon chain length and amount of prepared Cn TA+/montmorillonite, vermiculite nanocomposites. By the results of adsorption thermodynamics and kinetics equation was revealed adsorption reaction mechanism.The results showed that the interlayer spacing d001 values of Cn TA+/montmorillonite, vermiculite nanocomposites with same quaternary ammonium increased with alkyl chain length growth of quaternary ammonium salts; d001 values also increased with increasing dosage of quaternary ammonium salt in the Cn TA+/montmorillonite, vermiculite nanocomposites. The patterns of quaternary ammonium cation between montmorillonite, vermiculite interlayers arranged to the amount of quaternary ammonium cation and the carbon alkyl chain length.The removal of PAEs by Cn TA+/ nanocomposites is better than the removal by montmorillonite, vermiculite. With the increase of the amount of quaternary ammonium and quaternary alkyl carbon chain length, the removal of PAEs increases and then decreases on Cn TA+/montmorillonite and vermiculite nanocomposites. The best absorption of PAEs is 1.0CEC nanocomposites. Absorption of PAEs on Cn TA+/montmorillonite and vermiculite nanocomposites is not only about molecular size, but it is also about substances hydrophobic. Where the adsorption capacity increases with adsorption time increases, The adsorption of PAEs on Cn TA+/montmorillonite and vermiculite nanocomposites not affected by the initial p H substantially. Temperature has a certain influence on the adsorption and not so far. With increasing temperature the adsorption removal rate decreases.Using Langmuir isotherm model and Freundlich adsorption isotherm model to fit with the results of adsorption data. The two models are fitting for the adsorption process. PAEs adsorbed on sodium montmorillonite and vermiculite are mainly adsorbed on the surface, and which also include chemical adsorption such as ion exchange adsorption. On Cn TA+/montmorillonite and vermiculite nanocomposites absorption are mainly distribution effect of organic matter and also with surface absorption. The adsorption process can not be intended to fit with Pseudo-first-order adsorption model, however in line with the Pseudo-second-order adsorption model.