Study On Preparation Of Resin Preparation Of La-201 Resin And Its Adsorption And Dephosphorization Efficiency

Excessive discharge of phosphorus is one of the main factors leading to eutrophication of water.Eutrophication can occur when the phosphorus concentration in the water exceeds0.02mg/L.Therefore,research and development of deep phosphorus removal technology for wastewater is of great practical significance and scientific research value for solving environmental pollution prevention and control problems brought about by water eutrophication.As a commonly used phosphorus removal process,ion exchange resin method has been widely used in advanced treatment and drinking water treatment.However,the general resin's selective adsorption of phosphorus is poor,resulting in poor adsorption and removal of phosphorus.In this study,the phosphorus removal performance of macroporous strong basic styrene anion exchange resin?D201?in water was studied.The loading of rare earth element lanthanum greatly enhanced its phosphorus adsorption efficiency Methods and structural characterization,adsorption performance and phosphorus removal mechanism of the resin after loading were studied.The main conclusions are as follows:?1?Through the comparison of loading methods,the lanthanum loading of D201 was finally completed by the oscillation method,and the success of lanthanum loading on the resin surface was determined by the characterization of SEM,EDS,FTIR and XRD.?2?Through the static experiments of adsorption and desorption batches,the specific influence of the main influencing factors on the phosphorus adsorption and desorption performance of the resin was determined.The optimal loading conditions were determined:0.2mol/L of lanthanum chloride solution,the solid-liquid ratio of D201 resin and lanthanum chloride solution was 1:15,the reaction temperature was 50?,and the total reaction time of the preparation process was 24h.The optimal reaction conditions for the static adsorption experiment are:under the conditions of initial phosphorus concentration of 5mg/L,reaction temperature of 25?,solution pH of 7,adsorbent dosage of 0.5g/L,and reaction time of 4h,La The removal rate of phosphorus from-201 resin reached 99.1%.In addition,under the competition of coexisting anions,CO₃^2-has a greater inhibitory effect on the removal of phosphorus,while other anions(Cl^-,SO₄^2-,NO₃^-)have a small inhibitory effect.Static desorption experiments show that using 0.5mol/L sodium hydroxide solution to regenerate La-201 resin can achieve higher regeneration efficiency?the regeneration efficiency of one regeneration is 91.26%?.?3?Dynamic adsorption dephosphorization and desorption experiments were carried out on La-201 resin.The results show that increasing the height of the adsorption column,reducing the inlet water flow rate and reducing the initial phosphorus concentration can improve the phosphorus removal efficiency.The results of three adsorption regeneration experiments show that the resin The regeneration rate decreases as the number of regenerations increases.?4?The kinetics and thermodynamic equations of the phosphorus adsorption process of La-201 resin are fitted.The results show that in the adsorption thermodynamics,the La-201resin adsorption process of phosphorus combines the Langmuir model and the Frendlich model;According to the calculation results of La-201 resin,the phosphorus adsorption reaction is spontaneous and is an endothermic reaction,that is,appropriately increasing the initial temperature of phosphorus is conducive to improving the phosphorus adsorption efficiency of La-201 resin;McKay?Lagergren Level 2?reaction model.?5?The resin before and after lanthanum loading was characterized by SEM,EDS,FTIR and XRD.The results of mechanism analysis showed that its adsorption of phosphorus was mainly achieved by ion exchange,hydrogen bonding,complexation and chemical reaction.