The interaction between heavy metals and NOM during drinking water treatment processes

Doctoral Dissertation
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Abstract

The objective of this research is to examine the interaction of select heavy metals and natural organic matter (NOM) during coagulation and the metal preoxidation process before coagulation/adsorption for drinking water treatment. The metals used in this study include copper and arsenic, which are commonly found in source drinking water and represent metal cations and metal anions respectively. This research focuses on the investigation of copper-NOM (i.e., Cu(II)-NOM) interaction during coagulation/co-precipitation with aluminum based coagulants (Chapter 3), the arsenic redox speciation distribution in synthetic raw waters with the presence of NOM (Chapter 4), and the effect of NOM on arsenite (As(III)) and arsenate (As(V)) adsorption onto TiO2 surface (Chapter 5 and Chapter 6). The results suggest that the presence of Cu(II) in raw waters can facilitate NOM removal by coagulation. The effect of NOM on Cu(II) co-precipitation with alum is dependent on water pH. When pH is relatively low and no Cu(OH)2(s) or CuCO3(s) precipitates out, NOM can increase Cu(II) removal, whereas when pH is high and Cu(OH)2(s) or CuCO3(s) precipitates exist, NOM can inhibit Cu(II) removal through the coagulation (co-precipitation) with alum. The presence of NOM can mediate arsenic redox speciation distribution in a synthetic raw water. NOM can also facilitate As(III) oxidation by TiO2 in the absence of light and oxygen. Both As(III) and As(V) adsorption onto TiO2 surface can be decreased by the presence of NOM in raw water. This research addresses the important issue of how interactions between select heavy metals and NOM affects their ultimate fate during drinking water treatment processes. The experimental results provide insightful information for drinking water treatment plants to optimize operational conditions in order to remove select heavy metals and NOM from water.

Attributes

Attribute NameValues
URN
  • etd-04202007-141739

Author Guojing Liu
Advisor Jeffrey W. Talley
Contributor Robert Nerenberg, Committee Member
Contributor Jeremy B. Fein, Committee Member
Contributor Jeffrey W. Talley, Committee Chair
Contributor Clive R. Neal, Committee Member
Degree Level Doctoral Dissertation
Degree Discipline Civil and Environmental Engineering and Earth Sciences
Degree Name PhD
Defense Date
  • 2007-04-13

Submission Date 2007-04-20
Country
  • United States of America

Subject
  • TiO2

  • coagulation

  • NOM

  • copper

  • adsorption

  • arsenic

Publisher
  • University of Notre Dame

Language
  • English

Record Visibility and Access Public
Content License
  • All rights reserved

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