One-step Codeposition Of ZSM-5/PANI/PSS Electroactive Film And Its Application In Removing Low Concentration Pb²⁺from Waste Water

Electroactive Materia(EM)is a conductor,which can conduct both electrons and ions at the same time.The adsorption and release to target ions of the film can be controlled by changing the redox state of electroactive materials.The EMs are dived into conducting polymers(PANI,PPy,PEDOT),inorganic transition metal materials(hexacyanoferrate),and organic-inorganic hybrid materials,etc.Because of good electrical conductivity,stability,electrical activity,and ion exchange capacity,the organic-inorganic hybrid materials has attracted broad attention.As a kind of aluminum silicon molecular sieve,ZSM-5 has a high ion exchange capacity due to the selective complexation of ion with oxygen derived from Si-O,Al-O group.But its electrical conductivity is poor.Through the hybridization of ZSM-5 with organic conductive polymers,we can make full use of the ion exchange capacity,conductive ability and redox properties at the same time.In this work,an electroactive composite film composed of ZSM-5,Poly(sodium-p-styrenesulfonate)and PANI(ZSM-5/PANI/PSS)is controllably synthesized on Quartz crystal gold electrode in aqueous solution by the double pulse electrodeposition method.The highly crystalline nano-ZSM-5 is synthesized by hydrothermal method,which can be evenly dispersed in aqueous solution by the cell ultrasonic grinding treatment,which is better for synthesis of hybrid film.The hybrid film shows a high selectivity for heavy metal ion.ZSM-5 has better proton conduction and ion exchange capacity and can provide an acidic micro-environment for PANI to promote its electrical conductivity in neutral aqueous solutions.Electrochemical quartz microbalance(EQCM)combined with double-pulse method are applied to the syudy of the synthesis process of ZSM-5/PANI/PSS composite film.The effect of acid concentration degrees is studied.In addition,the adsorption efficiency at different potential range of heavy metal ions on is compared,ESIX was verified to be an effective countermeasures for heavy metal ion wastewater.ZSM-5/PANI/PSS composite film was synthesized on carbon felt by double pulse method.Atomic absorption spectrophotometer(AAS)was used to investigate the adsorption selectivity of ZSM-5/PANI/PSS composite film towards heavy metal ions.FT-IR,EDS,XRD,SEM,TEM are applied for the structure and morphology of the composite membrane XPS is employed to study the components of composite film and explain the stripping absorption mechanism.Experimental results show that the composite film have higher selectivity towards Pb2+ than other heavy metals.Adsorption process in different initial Pb2+ concentration was studied.The adsorption kinetics was fitted by Pseudo-first-order kinetic.The results show ZSM-5/PANI/PSS composite film exhibits high ion exchange capacity(235 mg/g)for Pb2+.The adsorption kinetics of Pb2+ could be described properly by the pseudo-first-order kinetic mode.The pseudo-first-order rate constant was 0.0227 g·mg-1·min-1 in ESIX process,which is higher than that of 0.0117 g·mg-1·min-1 in IX process.Therefor ZSM-5/PANI/PSS composite film is expected to be a promising ESIX material for wastewater treatment field.