Activation Of Peroxymonosulfate By Amino-modified Metal Organic Frameworks NH₂-MIL88B?Fe? For The Degradation Of Acid Orange ?

Aiming at the purification treatment of printing and dyeing wastewater,a typical azo dye-acid orange II was selected as the model pollutant,and amino-terephthalic acid ferric chloride were used as raw materials to prepare an amino functional group-modified MOF material by solvothermal method.NH₂-MIL88B?Fe?,the oxidative degradation of AOII by"NH₂-MIL88B?Fe?+PMS"and"NH₂-MIL88B?Fe?+PMS+visible light"systems were studied.FT-IR,SEM,XRD,TG,PL,DRS,EDS,XPS,BET,photocurrent,and impedance were used to analyze the composition,morphology,phase,specific surface area,surface chemical state,and photoelectric properties of NH₂-MIL88B?Fe?."NH₂-MIL88B?Fe?+PMS"system's degradation study of AOII shows that the system can effectively degrade AOII at a p H range of 3-9.After 30 minutes of reaction,the removal rate of AOII is 94%.When the p H value of AOII solution was not adjusted?p H=3?,the system had the best degradation effect on AOII.After 25 minutes of reaction,the removal rate of AOII was 97%.The degradation process of AOII is an endothermic reaction.Increasing the temperature,increasing the amount of NH₂-MIL88B?Fe?,and increasing the concentration of PMS are all conducive to the degradation of AOII.The AOII degradation reaction process complies with the quasi-first order kinetic model,and the activation energy of the reaction is57.88k J/mol.Free radical capture experiments and EPR tests show that ¹O₂ is the most active species.Because of the electron-donating group amino group is beneficial to the recycling of Fe^?/Fe^II redox couples through the organic ligand-to-metal charge transfer effect?LMCT?facilitates,the catalytic performance of the"NH₂-MIL88B?Fe?+PMS"system was improved.The catalyst has good cycle stability.After 5 cycles,95%of AOII can be removed in 25minutes."NH₂-MIL88B?Fe?+PMS+Vis"system for degradation of AOII shows that the system can almost completely degrade AOII at a p H range of 3-9.When the p H value of the AOII solution was not adjusted?p H=3?,the system had the best degradation effect on AOII.After15 minutes of reaction,the removal rate of AOII was 97%.Increasing the amount of NH₂-MIL88B?Fe?and increasing the concentration of PMS are beneficial to the degradation of AOII.Since the HCO₃^-will react with^·OH,increasing the concentration of HCO₃^-is not conducive to the degradation of AOII.Free radical capture experiments and EPR show that h⁺and ¹O₂ are the most active species.Compared with the"NH₂-MIL88B?Fe?+PMS"system,the"NH₂-MIL88B?Fe?+PMS+Vis"system reduced the amount of NH₂-MIL88B?Fe?and PMS after the introduction of light,and still showed excellent catalytic activity,this indicates that the"NH₂-MIL88B?Fe?+PMS+Vis"system is more efficient.There are obvious synergistic effects in the combination of the two advanced treatment methods of activated PMS and photocatalytic oxidation.The catalytic activity of the reaction system is enhanced because the amino functional group is excited to generate electrons under visible light.The electrons are transferred to the metal center through the charge transfer effect of the organic ligand to the metal?LMCT effect?,and the charge transfer of the light-activated metal cluster linker?LCCT?,O^2-transfer of electrons to Fe³⁺on the organic linking group greatly accelerates the Fe^III/Fe^II cycle in the?Fe?+PMS+Vis"system can effectively degrade a variety of dyes,has good cycle stability,and has broad application prospects.