Removal And Mechanism Studies Of Heavy Metal Irons By Coal/Polyethylene Crosslinked Composite Chelating Adsorbent

This paper was based on the Natural Science Fundation of China "Study on preparation and synergism mechanism of heavy metal ions of coal/polyethylene crosslinked composite chelating?51278418?".According to the physical and chemical characteristics of coal,this project adopts the high-energy ball milling process preparing superfine pulverized coal to increase its surface activity.In order to increase the chelating properties for heavy metal ions,polyethyleneimine?PEI?was grafted on the coal macromolecular structure.The active function group of coal and grafted group reacted with cross-linking agent to pressure coal/PEI composite chelation adsorption material,which has excellent chelation and adsorption properties,good mechanical prosperities and chemical stability.Study of coal/PEI crosslinked composite chelating adsorbent for Smelting Wastewater and chemical nickel plating wastewater of Pb²⁺,Cd²⁺ and Ni²⁺ adsorption of chelating properties through the static experiments.The adsorption of three kinds of heavy metal ions on coal/PEI composite chelation adsorption material accorded with the two-order adsorption kinetic model and Freundlich isotherm model.The adsorption capacities of Pb²⁺,Ni²⁺ and Cd²⁺ are respectively 74.44,65.28 and 63.77mg/g.Under the experimental conditions,coal/PEI crosslinked composite chelating agent on the adsorption of heavy metal ions in practical wastewater well.The adsorptive saturated coal/PEI composite chelation adsorption material is desorbed and regenerated with HCl solution,NaOH solution and ultrasonic ratio of 60%,respectively.The desorption efficiency of HCl solution to chelation adsorption material is the highest it is good.The composite chelation adsorption material are characterized by some instruments,such as specific surface and pore size analyzer,laser particle size analyzer,elemental analyzer,fourier transform infrared spectrometer,thermogravimetric analyzer and scanning electron microscope.The preparation mechanism of composite chelation adsorption material is studied.The physical and chemical structure of coal/PEI instrument is analyzed and the molecular structure model is established.The preparation process of coal/PEI composite chelation adsorption material and the analysis of FTIR,SEM and pore structure before and after adsorption are compared and analyzed.The results indicate that the coal/PEI composite chelation adsorption material is able to react with heavy metal ions mechanism.The adsorption of heavy metal ions in the solution can be obtained by the porous structure of coal/PEI crosslinked chelating adsorbent.The free amino in the molecular structure of coal/PEI composite chelation adsorption material chelate with heavy metal ions to form a stable chelate.Adsorption and chelation can play a synergistic role.