Synchronization Capture Behavior Of Heavy Metals And P-nitrophenyl Phenol In The Simulated Leachate Liquids On Compound Modified Montmorillonite

At present,the treatment of municipal solid waste in China is mainly used landfill method,resulting in a large number of landfill leachate.This kind of wastewater has the characteristics of high concentration of organic compounds,high content of heavy metals and ammonia nitrogen,if does not have the effective treated,it can easily cause the second pollution.Montmorillonite material are abundant and easily to obtain,it has the characteristic of economically and can synergistic treatment of heavy metals and organic compounds in landfill leachate,which is an ideal alternative for traditional adsorption materials.Na-bentonite was modified by cationic modification agent octadecyl trimethyl ammonium chloride?STAC?and organic chelating agent ethylenediamine?En?to prepare the montmorillonite composites?OCMt?for the composite pollution wastewater treatment.Based on analysis and characterization of XRD,FE-SEM,FT-IR,Automatic physical adsorption instrument,Elemental analyzer and Zeta potential analyzer,it was found that there was an increase in the basal spacing and the hydrophobic ability of FMC prepared by composite modification.FMC can realize the synchronization capture of heavy metal and the organic matter p-nitrophenyl pheno?PNP?.The results showed that the synchronization capture amount of Zn²⁺and PNP on OCMt was up to 224.2 mmol·kg^-1 under the condition that En/STAC ratio was 0.75,the adsortption temperature was 40 ^oC and the adsorption time was60 min,under the same condition the synchronization capture amount of Cu²⁺and PNP on OCMt was up to 252.96 mmol·kg^-1 and the synchronization capture amount of Cu²⁺,Zn²⁺and PNP on OCMt was up to 260.27 mmol·kg^-1.The interlayer spacing of the montmorillonite increases and the pore volume changes significantly after the composite modification,which improves the capacity of the montmorillonite to accommodate the pollutants.The main adsorption methods of montmorillonite on Zn²⁺and Cu²⁺were ion exchange and coordination complexation,while that of OCMt on PNP were determined by the content of organic C and organic N.The Pseudo-second-order can truly reflect the adsorption mechanism of OCMt on Zn²⁺,PNP and Cu²⁺,PNP,that the chemical sorption was the main rate limiting step in co-adsorption.