Aggregation Of Nano-TiO₂/DOM Complex Or Nano-TiO₂and Its Sorption For Phenanthrene

Due to its unique electronics, light, thermodynamics and light catalytic properties,nanometer material is becoming a kind of ideal current and potential industry applicationmaterials, which are used in all aspects of daily life.With this material continuous demandingand the products containing this material increasing, it is inevitable to release intoenvironment for nanopaticles,which is likely to lead to people in one of the exposure.Oncethey appear in the biosphere, this new type of particles will affect human and biological with akind of unforeseen form.Nano-TiO₂has a good development prospect in the auto industry andmany fields because of its precious optical properties. It’s widely used because of its highchemical stability, heat stability, super hydrophilic and non-toxic which can add to food.Theextensive use of titanium dioxide nanoparticles （nano-TiO₂） in daily life lead to concerns ontheir possible risks to the ecosystem.It is very necessary to evaluate and research the danger ofthe migration and detention of nano-TiO₂in the environment.In this paper,we consider TiO₂nanopaticles as a pollutant to characterize the existingform in the water environment, set up the determination method of TiO₂nanopaticles, andstudy the disperison and sedimentation of TiO₂nanopaticles in different environmentalfactors（pH, ionic strength,DOM） and adsorption behavior of phenanthrene onto TiO₂andTiO₂/HA of different particle sizes. Research initially revealed behavior and fate of TiO₂nanopaticle in water environment and adsorption mechanism of henanthrene onto TiO₂andTiO₂/HA of different particle sizes, This paper includes the following content and conclusion：TiO₂nanoparticles can absorb light and the absorbance is proportional to TiO₂nanoparticles concentration, so TiO₂nanoparticles can be determined based on theLambert–Beer law.Ruling the absorption of HA out,we determined with a better correlation indifferent environmental factors under508nm.Detection sensitivity is0.0210-3mg/ml.Dispersion and aggregation of TiO₂nanoparticles in different environmental factors wasstudied.Nanoparticles has a instability in water, because of its small size and large surfacearea.Measurements of nanoparticle aggregation due to attractive particle particle interactionsshow that ionic strength, pH, and adsorption of humic acid affect the aggregation of TiO₂nanoparticles in aqueous solutions, which are consistent with the trends expected from Derjaguin-Landau-Verwey-Overbeek （DLVO） theory.HA from different sources havedifferent functional group lead to have a different in aggregation.Sorption of phenanthrene by titanium oxides of different particle sizes was examined. Allparticles had low sorption for phenanthrene because of sorbed water molecules. Due to thelarger surface area （SA） of nanoparticles, they had higher sorption for phenanthrene than thelarger ones. Organic matter （OM） coating greatly enhanced phenanthrene sorption by allparticle sizes, noting the importance of sorbed OM in sorption of hydrophobic organiccompounds （HOCs）. Due to higher sorption site density in the sorbed OM phase on the largeroxide surfaces, SA-normalized distribution coefficients （KdSA） of phenanthrene byOM-regular oxide complexes （24.45μg/m2for200nm） were greater than the OM-coatedoxide nanoparticles （2.8511μg/m2for40nm and2.3093μg/m2for100nm）. Furthermore, theOM-regular oxide complexes had higher organic carbon content-normalized KdSAvalues ofphenanthrene （15187μg/m2for200nm） than the OM-nanoscaled oxide complexes （331.53μg/m2for40nm and1560.3μg/m2for100nm）. This variation may be due to differentphysical forms and fractionation of the loaded OM on regular and nanoscaled oxide particles.When we need evaluate the nanometer TiO₂environmental behavior and risk,theinformation of environmental behavior of TiO₂nanoparticles about its migrationand sorptionof phenanthrene in water environment can offer scientific basis in this paper.