The Preparation Of Sodium Alginate Composite Membrane And The Study Of Its Methylene Blue Adsorption Performance

With the rapid development of industry,agriculture and medicine and health industry.A huge amount of wastewater containing heavy metal,noxious substance and dyes has been discharged into the aquatic environment and underground water,which has caused damaging results to our daily life and living conditions.Several wastewater treatment methods such as physical precipitation,chemical precipitation,chemical oxidation,REDOX method,photochemical degradation,membrane filtration,electrochemical treatment and adsorption have been explored to remove the pollutants from wastewater.Among these treatments above,adsorption is the most simple,low-cost,could remove far more contaminants and effective than any other purification methodsAs new nanomaterials have developed so rapidly,the application and research in sewage treatment has got remarkable achievements.Sodium alginate has already been widely used and investigated in various areas of applications due to its unique properties such as biocompatibility,nontoxicity,hydrophilicity,good membrane-forming performance,exceptional formability and low cost.In this passage,the porous multiwalled carbon nanotubes/calcium alginate membrane(MWCNT/CA)and multiwalled carbon nanotubes/graphene oxide/calcium alginate membrane(MWCNT/GO/CA)were prepared by blending and vacuum freeze drying method.The properties of the membranes were characterized by SEM,FTIR and TGA.Meanwhile,bath adsorption experiments were conducted to investigate the influence of various conditions on the adsorption,including temperature,initial concentration of MB,p H,absorbent dosage and contacting time.Kinetic studies indicated that the kinetics of the adsorption of MB onto MWCNT/CA follows pseudo-second-order model.The adsorption equilibrium data were analyzed by using various adsorption isotherm models and the results showed that adsorption behavior could be described reasonably by the Langmuir isotherm.The maximum adsorption capacity was up to 1890.35 mg/g and 2748.76mg/g,indicating that MWCNT/CA is a promising adsorbent for removal of MB from aqueous solutions.Thermo dynamic analysis demonstrated that the adsorption of MB onto the membrane was a spontaneous and exothermal process.As novel nanomaterials,CNTs have been widely used in sewage treatment due to its unique one-dimensional structure,high chemical stability,high pore volume ratio,huge specific surface areas and strong hydrophobicity.It has great potential for application in adsorption of heavy metal ions and dyes fast and effectively.Graphene oxide(GO)was prepared with a modified Hummers method,the properties of GO was characterized by SEM,FTIR and TGA.