The influence of ionic strength and organic compounds on nanoparticle TiO2 (n-TiO2) aggregation

Jaewoong Lee, Shannon L Bartelt-Hunt, Yusong Li, Erica Jeanne Gilrein

Research output: Contribution to journalArticle

14 Citations (Scopus)

Abstract

This study investigated the aggregation of n-TiO2 in the presence of humic acid (HA) and/or 17β-estradiol (E2) under high ionic strength conditions simulating levels detected in landfill leachate. Aggregation of n-TiO2 was strongly influenced by ionic strength as well as ionic valence in that divalent cations (Ca2+) were more effective than monovalent (Na+) at the surface modification. HA or E2 enhanced aggregation of n-TiO2 in 20 mM CaCl2, however little aggregation was observed in 100 mM NaCl. Similarly, we observed only the increased aggregation of n-TiO2 in the presence of HA/E2. These results showed the critical role of particles' surface charges on the aggregation behaviors of n-TiO2 that HA plays more significantly than E2. However, the slightly increased zeta potential and aggregation of n-TiO2 in the combination of HA and E2 at both 20 mM CaCl2 and 100 mM NaCl means that E2 has influenced on the surface modification of n-TiO2 by adsorption. Based on the aggregation of n-TiO2 under high ionic strength with HA and/or E2, we simulated the mobility of aggregated n-TiO2 in porous media. As a result, we observed that the mobility distance of aggregated n-TiO2 was dramatically influenced by the surface modification with both HA and/or E2 between particles and media. Furthermore, larger mobility distance was observed with larger aggregation of n-TiO2 particles that can be explained by clean bed filtration (CFT) theory.

Original languageEnglish (US)
Pages (from-to)187-193
Number of pages7
JournalChemosphere
Volume154
DOIs
StatePublished - Jul 1 2016

Fingerprint

Ionic strength
Organic compounds
Nanoparticles
Osmolar Concentration
organic compound
Humic Substances
Agglomeration
humic acid
Surface treatment
nanoparticle
Chemical Water Pollutants
aggregation behavior
Divalent Cations
Zeta potential
Surface charge
Land fill
Adsorption
Porous materials
porous medium
Estradiol

Keywords

  • Aggregation
  • E2
  • HA
  • IS
  • Mobility
  • N-TiO

ASJC Scopus subject areas

  • Environmental Engineering
  • Environmental Chemistry
  • Chemistry(all)
  • Pollution
  • Health, Toxicology and Mutagenesis

Cite this

The influence of ionic strength and organic compounds on nanoparticle TiO2 (n-TiO2) aggregation. / Lee, Jaewoong; Bartelt-Hunt, Shannon L; Li, Yusong; Gilrein, Erica Jeanne.

In: Chemosphere, Vol. 154, 01.07.2016, p. 187-193.

Research output: Contribution to journalArticle

@article{b2a5f22a34d945a5a33381175f42e6dc,
title = "The influence of ionic strength and organic compounds on nanoparticle TiO2 (n-TiO2) aggregation",
abstract = "This study investigated the aggregation of n-TiO2 in the presence of humic acid (HA) and/or 17β-estradiol (E2) under high ionic strength conditions simulating levels detected in landfill leachate. Aggregation of n-TiO2 was strongly influenced by ionic strength as well as ionic valence in that divalent cations (Ca2+) were more effective than monovalent (Na+) at the surface modification. HA or E2 enhanced aggregation of n-TiO2 in 20 mM CaCl2, however little aggregation was observed in 100 mM NaCl. Similarly, we observed only the increased aggregation of n-TiO2 in the presence of HA/E2. These results showed the critical role of particles' surface charges on the aggregation behaviors of n-TiO2 that HA plays more significantly than E2. However, the slightly increased zeta potential and aggregation of n-TiO2 in the combination of HA and E2 at both 20 mM CaCl2 and 100 mM NaCl means that E2 has influenced on the surface modification of n-TiO2 by adsorption. Based on the aggregation of n-TiO2 under high ionic strength with HA and/or E2, we simulated the mobility of aggregated n-TiO2 in porous media. As a result, we observed that the mobility distance of aggregated n-TiO2 was dramatically influenced by the surface modification with both HA and/or E2 between particles and media. Furthermore, larger mobility distance was observed with larger aggregation of n-TiO2 particles that can be explained by clean bed filtration (CFT) theory.",
keywords = "Aggregation, E2, HA, IS, Mobility, N-TiO",
author = "Jaewoong Lee and Bartelt-Hunt, {Shannon L} and Yusong Li and Gilrein, {Erica Jeanne}",
year = "2016",
month = "7",
day = "1",
doi = "10.1016/j.chemosphere.2016.03.059",
language = "English (US)",
volume = "154",
pages = "187--193",
journal = "Chemosphere",
issn = "0045-6535",
publisher = "Elsevier Limited",

}

TY - JOUR

T1 - The influence of ionic strength and organic compounds on nanoparticle TiO2 (n-TiO2) aggregation

AU - Lee, Jaewoong

AU - Bartelt-Hunt, Shannon L

AU - Li, Yusong

AU - Gilrein, Erica Jeanne

PY - 2016/7/1

Y1 - 2016/7/1

N2 - This study investigated the aggregation of n-TiO2 in the presence of humic acid (HA) and/or 17β-estradiol (E2) under high ionic strength conditions simulating levels detected in landfill leachate. Aggregation of n-TiO2 was strongly influenced by ionic strength as well as ionic valence in that divalent cations (Ca2+) were more effective than monovalent (Na+) at the surface modification. HA or E2 enhanced aggregation of n-TiO2 in 20 mM CaCl2, however little aggregation was observed in 100 mM NaCl. Similarly, we observed only the increased aggregation of n-TiO2 in the presence of HA/E2. These results showed the critical role of particles' surface charges on the aggregation behaviors of n-TiO2 that HA plays more significantly than E2. However, the slightly increased zeta potential and aggregation of n-TiO2 in the combination of HA and E2 at both 20 mM CaCl2 and 100 mM NaCl means that E2 has influenced on the surface modification of n-TiO2 by adsorption. Based on the aggregation of n-TiO2 under high ionic strength with HA and/or E2, we simulated the mobility of aggregated n-TiO2 in porous media. As a result, we observed that the mobility distance of aggregated n-TiO2 was dramatically influenced by the surface modification with both HA and/or E2 between particles and media. Furthermore, larger mobility distance was observed with larger aggregation of n-TiO2 particles that can be explained by clean bed filtration (CFT) theory.

AB - This study investigated the aggregation of n-TiO2 in the presence of humic acid (HA) and/or 17β-estradiol (E2) under high ionic strength conditions simulating levels detected in landfill leachate. Aggregation of n-TiO2 was strongly influenced by ionic strength as well as ionic valence in that divalent cations (Ca2+) were more effective than monovalent (Na+) at the surface modification. HA or E2 enhanced aggregation of n-TiO2 in 20 mM CaCl2, however little aggregation was observed in 100 mM NaCl. Similarly, we observed only the increased aggregation of n-TiO2 in the presence of HA/E2. These results showed the critical role of particles' surface charges on the aggregation behaviors of n-TiO2 that HA plays more significantly than E2. However, the slightly increased zeta potential and aggregation of n-TiO2 in the combination of HA and E2 at both 20 mM CaCl2 and 100 mM NaCl means that E2 has influenced on the surface modification of n-TiO2 by adsorption. Based on the aggregation of n-TiO2 under high ionic strength with HA and/or E2, we simulated the mobility of aggregated n-TiO2 in porous media. As a result, we observed that the mobility distance of aggregated n-TiO2 was dramatically influenced by the surface modification with both HA and/or E2 between particles and media. Furthermore, larger mobility distance was observed with larger aggregation of n-TiO2 particles that can be explained by clean bed filtration (CFT) theory.

KW - Aggregation

KW - E2

KW - HA

KW - IS

KW - Mobility

KW - N-TiO

UR - http://www.scopus.com/inward/record.url?scp=84961943000&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84961943000&partnerID=8YFLogxK

U2 - 10.1016/j.chemosphere.2016.03.059

DO - 10.1016/j.chemosphere.2016.03.059

M3 - Article

VL - 154

SP - 187

EP - 193

JO - Chemosphere

JF - Chemosphere

SN - 0045-6535

ER -