Study On The Adsorption Properties Of Heavy Metal Ions On The Pine Cone/Pine Needle Needle Based Carbon Materials

With the rapid development of industry,environmental pollution is becoming more and more serious,heavy metal ions are the main source of environmental pollution.Carbon material is a kind of excellent material for adsorption of heavy metal ions,and the adsorption capacity of nitrogen containing carbon material is more efficient.Pine cone and pine needle have a wide range of sources,while the nitrogen and pore system contained rich.Therefore,this paper takes pine cone and pine needle as the carbon source,after alkali treatment of carbonization,two kinds of plant based carbon materials were successfully prepared,Pine cone based carbon materials AC_PC and pine needle based carbon materials AC_PN.It was characterized by infrared spectroscopy,elemental analysis,SEM and static surface adsorption.The adsorption properties of two kinds of four kinds heavy metal ions on Zn²⁺,Pb²⁺,Cd²⁺ and Cu²⁺ were studied.Pine cone based carbon materials AC_PC and pine cine based carbon materials AC_PN has developed pore structure and abundant nitrogen.The specific surface area of AC_PC-700-2 was as high as 746.9m²/g,the nitrogen content of AC_PC-400-3 was 0.82%,the specific surface area of AC_PN-700-2 was as high as 699.9m²/g,and the nitrogen content of AC_PN-400-2 was up to 1.26%.The two kinds of carbon materials prepared by the developed pore structure and rich nitrogen functional groups showed good adsorption properties for metal ions.The experimental results show that the materials prepared under different carbonization conditions have different adsorption properties for heavy metal ions.AC_PC for Zn²⁺,Pb²⁺,Cd²⁺ and Cu²⁺ four kinds of heavy metal ions of the best samples were AC_PC-400-3,AC_PC-600-2,AC_PC-600-3 and AC_PC-600-3,adsorption amount was 42.29 mg/g,73.36 mg/g,43.20 mg/g and 49.37 mg/g.The adsorption behavior was in accord with the two order kinetic model,and all of them were Langmuir monolayer adsorption.pH and temperature have a great effect on adsorption,and the adsorption capacity increases with the increase of pH.The results of adsorption thermodynamics showed that the adsorption of AC_PC on ions was an endothermic spontaneous process.AC_PC has a good performance of reuse.The adsorption of heavy metal ions by AC_PN is similar to that of AC_PC,AC_PN for Zn²⁺,Pb²⁺,Cd²⁺ and Cu²⁺ four kinds of heavy metal ions of the best samples were AC_PN-600-2,AC_PN-700-2,AC_PN-500-2 and AC_PN-600-2,adsorption capacity was 31.75 mg/g,200.51 mg/g,40.53 mg/g and 41.77 mg/g.Similarly,AC_PN also has a good performance of reuse.