Study On The Preparation Of Ferrocene Contained MOFs And Their Derivatives And Composites And Their Application In Removal Of Bisphenol A

Water pollution caused by organic pollutants such as plastic additives,organic dyes,antibiotics and drugs in industrial wastewater has become one of the most urgent problems to be solved.These pollutants are difficult to be removed by adsorption and biodegradation method,which deeply threats the health of human beings.Therefore,the degradation of organic pollutants in industrial wastewater before release is rather important.Ferrocene(Fc)is considered as a promising catalyst candidate in heterogeneous advanced oxidation processes(AOP)field since its low cost,good stability,superior optical and unique redox properties;however,bare Fc suffers from the serious aggregation,significantly limiting its further application.To address above issue,four catalytic systems were designed using Fc-contained metal organic frame material(MOF),Fc-contained MOF composite and/or Fc doped MOF derivative as catalysts and employing bisphenol A(BPA)as the target pollutant,respectively,aiming to obtain a catalytic system with good stability,excellent catalytic activity,clear catalytic mechanism,wide application range and great practical application potential.The main research contents and experimental results of this thesis are listed as follows:(i)Five kinds of Zr-Fc MOF with different morphology and microstructure were synthesized through solvothermal method by adjusting the concentration of acetic acid.The optimal synthesis conditions and microstructure of tremella-like Zr-Fc MOF(TMOF-100)have been determined.The synthesized TMOF-100 exhibited many merits,such as large specific surface area,sufficient unsaturated Zr sites,high Fe content,high stability and strong visible light absorption ability,which endowed its outstanding photocatalytic activity for peroxymonosulfate(PMS)activation to degrade BPA under visible light irradiation.As a result,BPA can be entirely removed within 60 min over TMOF-100/PMS/Vis system,the corresponding apparent rate constant(k)was 0.045 min-1.Based on the results of quenching experiments,electron paramagnetic resonance and electrochemical testing,various reactive active species(ROS)including·OH,SO4-,·O2-and 1O2 were generated,in which ·OH and SO4-· dominated the BPA degradation process.Moreover,the TMOF-100/PMS/Vis system exhibited high stability,the degradation efficiency of BPA can be maintained at high level(>90%)after using five continuous cycles.(ii)Four Fc-modified Uio-66-NH2(U-F-X)with different content of Fc group were obtained by Schiff base reaction between Fc-CHO and Uio-66-NH2.Two series of 2D/3D composites(U@CN-Y and U-F-2@CN-Z)were prepared by changing the mass ratio of Uio-66-NH2 or U-F-2 to CN,which were applied as photocatalysts for BPA degradation.The experimental results indicated that U-F-2@CN-2.5/PMS/Vis system exhibited optimal photocatalytic activity,BPA could be degraded completely within 60 min.In addition,this outstanding photocatalytic activity could be maintained at high level in a wide pH range and appropriate temperature region.Benefiting from the good chemical stability,outstanding optical property and in-situ generation of interfacial heterojunction,the interfacial transport of photogenerated charges followed the Z-scheme mechanism,which can accelerate the charge separation and transport to yield abundant ROS under visible light.Moreover,the high catalytic activity can be remained in real water environment,such as tap water,Xixi wetland water and West Lake water,the BPA removal rate were over 95%.Besides,other typical organic pollutants(such as methyl orange,rhodamine B,Congo red,tetracycline and p-chlorophenol)also could be efficiently removed by U-F-2@CN-2.5/PMS/Vis system,suggesting the great practical application value of synthesized U-F-2@CN-2.5.(iii)A series of Fc@ZIF-8-X composites with different Fc content were prepared by one-pot method,which were applied as precursors of Fe-N-C-X-T SACs,their microstructure and catalytic performance for BPA degradation were systematically investigated.Among Fe-N-C-X-T,Fe-N-C-1-900 displayed highest catalytic activity to active PMS for BPA degradation,94.3%BPA could be removed within 10 min,the corresponding k reached to 0.395 min-1,which was 9.5 times faster than that of counterpart N-C-900 due to the synergistic effect of radical pathway,non-radical pathway and electron-transfer.In Fe-N-C-1-900/PMS system,1O2 has been proved as the main ROS to control the BPA degradation process.Furthermore,the Fe-N-C-1-900/PMS and Fe-N-C-1-900/BPA interfacial interactions were investigated by density functional theory(DFT)calculations,which disclosed the formation of high-valent iron-oxo species(Fe(Ⅳ)=O)and interfacial electron-transfer to comprehensively and thoroughly investigate the possible mechanism of BPA degradation.Besides,Fe-N-C-1-900/PMS system possessed good universality,which can not only exhibit high catalytic activity in actual water environment,but also can effectively degrade various organic pollutants(such as such as methyl orange,rhodamine B,Congo red,tetracycline,chloramphenicol and p-chlorophenol).(iv)Using Fc@ZIF-8 as the precursor material to obtain Fe-N-C-1-900 SAC,which was hybridized with Fc-modified CN to built heterostructured photocatalyst.Among various composites,the FCF-0.05 displayed optimal photocatalytic activity,BPA can be removed completely over FCF-0.05/PMS/Vis system within 60 min,the corresponding k reached to 0.053 min-1,which were 24 times and 10 times higher than those of CN/Vis and CN/PMS/Vis systems,respectively,deriving from the efficiently charge separation since in-situ generation of interfacial heterojunction.Moreover,FCF-0.05/PMS/Vis system exhibited high stability and superior catalytic activity in real water and outdoor environment.Furthermore,the BPA degradation mechanism and pathway have been identified by combination experimental(quench testing,EPR and LC-MS techniques)and DFT calculations method,which exhibited huge practical application value and provided an novel insight in the synthesis of cost-effective photocatalysts.