Study On Preparation Of Activated Carbon Based On Pine Cone/pine Needle And Adsorption And Desorption Properties Of Pb²⁺

In China,pine cones and pine needles are extensive and inexpensive.Because of its developed pore structure and rich in nitrogen,oxygen and other elements,the prepared activated carbon can be physical and chemical adsorption,which can enh anced the adsorption capacity.In the face of the condition of scarce resources,it is significative to rationally utilize and redevelop the abandoned pine cones and needl es.Therefore,pine tower and pine needle were selected as raw materials and KOH as activator to make pine cone/pine needle-based activated carbon（ACp）,glutarald ehyde was used as a crosslinking agent to make cross-linked pine cone/pine needle-based activated carbon（CACp）,Fe Cl₃as magnetization agent to make magnetic pin e cone/pine needle-based activated carbon（MACp）.The effects of preparation and a dsorption-desorption conditions on the adsorption and desorption properties of three activated carbons had be studied.The adsorption kinetics and adsorption isotherm m odel were analyzed.The adsorption mechanism of activated carbon on Pb²⁺was an alyzed by various characterization methods.The results show that:（1）Pine cone and pine needle as raw materials and KOH as activator to ma nufacture ACp to use for adsorption of Pb²⁺.The maximum adsorption capacity of Pb²⁺was 210.73mg/g.The adsorption process was in accordance with the pseudo-se cond-order kinetic theory model and Freundlich adsorption isotherm model,and che mical adsorption was the main adsorption process.ACp has developed pore structur e,large specific surface area,and abundant nitrogen and oxygen functional groups on the surface,so that ACp has a high adsorption performance.（2）The carbonization precursor of ACp as the raw material and glutaraldehy de as the cross-linking agent to manufacture CACp to use for adsorption of Pb²⁺.The maximum adsorption capacity of Pb²⁺was 280.73mg/g,which was higher than ACp.CACp has higher specific surface area,more developed pore structure,more f unctional groups and more ordered internal structure than ACp,and CACp has stro nger adsorption capacity.（3）The carbonization precursor of CACp as raw material and Fe Cl₃as mag netizer to manufacture MACp to use for adsorption of Pb²⁺.The maximum adsorpti on capacity of Pb²⁺was 272.24mg/g,and the adsorption capacity was reduced.MA Cp has been successfully magnetized,and the relative content of iron is up to 12.11wt%,which has a strong magnetic property,improving the applicability of pine to wer/pine needle-based activated carbon.