Adsorption Of Heavy Metal Ions By Polyvinylidene Fluoride (PVDF)/SIO 2 Hybrid Membrane

In recent years,rapid development of industry and human activities have caused serious pollution of heavy metals to natural resources such as water,soil and organisms.Nowadays,people have studied chemical precipitation,electrolysis,coagulation,ion exchange and adsorption to remove heavy metal ions.Adsorption is one of the most popular technology to treat such wastewater among above methods due to its low cost and high efficiency.The traditional adsorbents have many disadvantages,such as low adsorption capacity,difficult regeneration,secondary pollution.Mesoporous silica is excellent adsorption material due to high specific surface area,large pore volume,good stability and high adsorption capacity.However,mesoporous silica is present in the form of powder,which is easy to agglomerate in the process of adsorption,leading to the decrease of adsorption capacity,and it is difficult to reuse.Therefore,it is necessary that mesoporous silica load on the carrier.The polyvinylidene fluoride membrane had obtained widely used because of good thermal stability,oxidation resistance and mechanical properties.Pure PVDF membrane materials lack of functional groups that can chelate with heavy metal ions.Hence,pure PVDF membrane can not effectively remove heavy metal ions from aqueous solution.In recent years,the membrane was modified by introducing functional groups(amino groups,carboxyl groups),which can improve adsorption capacity of heavy metal ions.However,preparation of adsorption membrane require strict conditions,complex process,high cost,therefore,it is urgent to develop a adsorptive membrane that possess simple preparation process,low cost,high adsorption capacity and stable properties to remove heavy metal ions from aqueous solution.In this paper,the PVDF hybrid membrane was prepared by co-polymerization method and ion imprinted technique including PVDF/AFMS hybrid membrane,PVDF/mesoporous silica hybrid membrane and PVDF/IIMS hybrid membrane.The prepared hybrid membranes were characterized using ATR-FTIR,SEM and TG tests.The results show that modified silica was successfully embedded into the PVDF membrane.The PVDF membranes which were added mesporous silica were improved hydrophilicity and pure water flux through porosity,contact angle,flux test.The hybrid membranes were used to remove heavy metal ions from aqueous solution,the hybrid membrane exhibited excellent adsorption capacity for heavy metal ions.