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Properties of residual titanium dioxide nanoparticles after extended periods of mixing and settling in synthetic and natural waters.

ABSTRACT: Titanium dioxide nanoparticle (TiO₂ NP) discharged into water bodies can affect ecosystems and human health adversely. We studied the properties of residual TiO₂ NPs with and without gentle mixing (to simulate a natural environment more closely) and after settling for 12-h periods. Surface complexation, dynamic particle size changes, and TiO₂ NP destabilization in synthetic and lake waters were investigated. The accumulation of inert ions (Na⁺ and Cl^-) in the diffuse layer which was not discussed in other studies was supposed to be the main reason that aggregation occurred slowly and continuously. PO₄^3- stabilized and destabilized TiO₂ NPs at 10?mM and 100?mM, respectively. Destabilization occurred because high ionic strength overwhelmed increased negative charges of TiO₂ NPs by complexation with PO₄^3-. TiO₂ NP destabilization was achieved in approximately 12?h in synthetic and lake waters, and is attributed to the slow diffusion of ions into aggregates. Despite the presence of moderately high concentrations of natural organic matter, which tends to stabilize TiO₂ NPs, the addition of 20?mM PO₄^3- destabilized the TiO₂ NPs in lake water. Smaller aggregate sizes formed compared with those before destabilization, which indicates that stable residual TiO₂ NPs could exist in aquatic environments after extended periods.

SUBMITTER: Zhang C

PROVIDER: S-EPMC5577155 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature

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Properties of residual titanium dioxide nanoparticles after extended periods of mixing and settling in synthetic and natural waters.

Zhang Chunpeng C Lohwacharin Jenyuk J Takizawa Satoshi S

Scientific reports 20170830 1

Titanium dioxide nanoparticle (TiO2 NP) discharged into water bodies can affect ecosystems and human health adversely. We studied the properties of residual TiO2 NPs with and without gentle mixing (to simulate a natural environment more closely) and after settling for 12-h periods. Surface complexation, dynamic particle size changes, and TiO2 NP destabilization in synthetic and lake waters were investigated. The accumulation of inert ions (Na+ and Cl<s ...[more]

PMID: 28855538

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Dataset Information

Properties of residual titanium dioxide nanoparticles after extended periods of mixing and settling in synthetic and natural waters.

Publications

Properties of residual titanium dioxide nanoparticles after extended periods of mixing and settling in synthetic and natural waters.

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