Preparation Of Au Nanoparticles Composites And Adsorption Properties For Pyrene In Aqueous Phase

Persistent Organic Pollutants(POPs)refer to long half-life organic chemicals which can accumulate through the food web and have adverse effects on human health.The harms to human and environment from POPs have been a global problem.The most representative one is Polycyclic Aromatic Hydrocarbons,which is supposed to be one of the three most serious environmental problems affecting human health and survival with the Ozone Depletion and Green House Effects in the 21th century.Polycyclic Aromatic Hydrocarbons(PAHs)refer to a kind of hydrocarbons containing two or more benzene rings.Some of them are carcinogenic,teratogenic and mutagenic.We choose pyrene a representative kind of PAHs.As the interaction between Au nanoparticles and the benzene,we prepared three kinds of Au nanocomposites studying on its adsorption properties for pyrene in aqueous solution.The Au nanoparticles which size is about 13 nm were prepared by sodium citrate reduction method.The Fe3O4 which size is about 200 nm were prepared by solvothermal hot method and aminated with KH-550.Fe3O4@Au magnetic composites were prepared based on assembly strategy.Some means such as SEM,TEM,XRD and elemental analysis were used to characterize the composite particles.The results of adsorption experiments showed as follows.Under the optimal conditions:the initial pyrene concentration is 0.4 ?g·mL-1 Fe3O4@Au dosage is 100 mg,contact time is 30 min,the pH value is 7,the maximum adsorption capacity of pyrene is about 80 ?g·g-1.As the Fe3O4 particles easily gathered,SiO2 was coated on the surface of Fe3O4 particles.The Fe3O4@SiO2 which size is about 200 nm were prepared and aminated with KH-550.Fe3O4@SiO2@Au magnetic composites were obtained based on assembly strategy.Some means such as SEM,TEM,XRD and elemental analysis were used to character the composite particles.The results of adsorption experiments showed as follows.Under the optimal conditions:the initial pyrene concentration is 0.4 ?g·mL-1,Fe3O4@SiO2@Au dosage is 50 mg,contact time is 30 min,the pH value is 7,the maximum adsorption capacity of pyrene is about 153 ?g·g-1.Graphene oxide modified with PVP was disperse easily in the solution.Graphene oxide/Au nanoparticle hybrids(GO/PDDA/AuNPs)were obtained based on a self-assembly strategy,in which poly(diallyldimethyl ammonium chloride)(PDDA)was used as the functional macromolecules to prepare the stable cationic polyelectrolyte-functionalized graphene oxide and anchor the AuNPs,and the modified GO with positive potential can concentrate the negatively charged target molecules.Some means such as SEM,TEM,XPS and EDS were used to character the composite materials.The results of adsorption experiments showed as follows.Under the optimal conditions:the initial pyrene concentration is 0,4 dg·mL-1,GO/Au dosage is 30 mg,contact time is 30 min,the pH value is 7,the maximum adsorption capacity of pyrene is about 305?g·g-1 Finally,the adsorption isotherms and kinetics model of the process were discussed too.