Adsorption Properties Of Modified Orange Peel For Waste Water Containing Pb(?)

People will produce a large amount of heavy metal wastewater in the process of life and production,such as electroplating metallurgy,mining and chemical industry,etc.The heavy metal ions generated cannot be degraded when they enter the water body,and eventually enter the human body through the food chain,causing harm to human health.Orange peel,as a cheap agricultural and forestry waste,has become the object of our study,and can be used to turn waste into treasure.It is particularly suitable for the treatment of heavy metal wastewater with low concentration.It has a wide range of sources and is relatively economical,so it is a promising adsorption material.Orange peel?OP?is adopted in this experiment as raw material,through alkaline oxidation?HOOP?and Fe???load modification?FeOP?to different modified adsorbent preparation,preparation into water and burning charcoal load Fe₃O₄ magnetic materials?CXOP?,the single factor control variables research adsorbent adsorption experiment was carried out on the waste water containing lead,to study the adsorption dosing quantity,pH value,adsorption time and the concentration of adsorbate on the adsorbent adsorption effect of lead,and through the dynamic equation and adsorption isothermal adsorption mechanism model to simulate the experimental data research,The mechanism of adsorption reaction was explored by means of modern analytical methods such as FTIR,SEM and EDS.The research results are summarized as follows:?1?at pH5.5,the initial ion concentration of 50mg/L and dosage of 0.05g reached adsorption equilibrium at 30?at 20min,and the removal rate of lead by OP was 88.57%.Under the same condition,the removal rate of lead by FeOP was 95.66%,98.59%by HOOP within 60min,and 93.88%by CXOP at pH 5.The adsorption capacity of orange peel was higher than that of ordinary orange peel.And all have reusable value.?2?the effect of Cd²⁺,Ni²⁺and Cu²⁺on Pb²⁺adsorption was investigated in this experiment.The higher the atomic weight,the higher the energy,the easier it is to collide with the adsorbent surface,and thus easier to be adsorbed,indicating that Pb²⁺is the easiest to be adsorbed,while other ions can only form competitive influence.Since the effect of competing adsorption is mainly related to ion electronegativity and ion radius,the effect of different ions on Pb²⁺adsorption is also different,mainly because the ion radius and ion electronegativity correspond to the actual adsorption sequence(Cu²⁺>Ni²⁺>Cd²⁺).?3?the adsorption isotherm fitting showed that the adsorption of lead by OP,HOOP,FeOP and CXOP belonged to the single molecular layer chemical adsorption,which was consistent with the Langmuir isotherm adsorption model.The simulation of adsorption experiment data of four materials by kinetic equation is more in line with quasi-second order kinetics.SEM found OP,HOOP,FeOP,CXOP in the entire surface before and after adsorption form structure has changed,before by adsorption of tight after absorption of irregular shape to the full,shows that the surface of the material and internal morpHological structure is advantageous to the Pb???adsorption;XRD indicated that the crystal plane diffraction of the loaded material was consistent with the standard spectrum of Fe₃O₄,and the magnetic hydrothermal carbon was successfully prepared by this experiment.EDS,FTIR and XPS characterization indicates that the adsorption of lead is the main mechanism of the C=O,O-H and other functional groups and Pb???complexes formation,and the aromatic cycloparaffin CXOP form conjugate PI with Pb???Pb???-PI;Ion exchange action happened at the same time,like a HOOP of K⁺,Ca²⁺and Pb???ion exchange action happens,formation of Pb???-exists in the form of Complex compounds,so chemical adsorption is the main adsorption mechanism.