Abiotic degradation of nitrates using zero-valent iron and electrokinetic processes

Chin F. Chew, Tian C. Zhang

Research output: Contribution to journalArticle

27 Citations (Scopus)

Abstract

Nitrate transformation in artificial saturated soils made from sand and/or clay mixed with nitrate-contaminated water was investigated using (1) zero-valent iron treatment, (2) electrokinetics treatment alone, and (3) electrokinetics coupled with an iron treatment wall placed near the cathode or anode. Approximately 75-98% of the nitrates were transformed using zero- valent iron to treat the artificial soils. The major products in the zero- valent-assisted transformation were nitrogen gases (75-81%) and ammonia- nitrogen (2-18%). Nitrite-nitrogen was less than 1% in all these experiments. With electrokinetics alone, some nitrates were transformed (about 30%). Nitrate transformation was about 60% with the iron wall placed near the cathode, and was about 95% with the iron wall placed near the anode. The major products were nitrogen gases and ammonia. Nitrite-nitrogen was less than 1% in these runs. Electroosmotic permeability (Ke) variation appeared to be dependent on the voltage in the reactor. The pH variations over time in electrokinetics (control and iron wall near cathode) indicated the movement of a small acid front. However, the presence of an iron wall near the anode tended to increase the pH slightly. The pH variations over time in the electrokinetics coupled with an iron wall depend on the location of the iron wall. This study demonstrates that electrokinetics coupled with an iron wall near the anode is capable of remediating nitrate contamination in low permeability soils.

Original languageEnglish (US)
Pages (from-to)389-401
Number of pages13
JournalEnvironmental Engineering Science
Volume16
Issue number5
DOIs
StatePublished - Jan 1 1999

Fingerprint

Nitrates
Iron
nitrate
iron
Degradation
degradation
Nitrogen
Anodes
nitrogen
Cathodes
Nitrites
Soils
Ammonia
nitrite
ammonia
Gases
electrokinetics
permeability
soil
gas

Keywords

  • Electrokinetics
  • Groundwater remediation
  • Nitrates
  • Treatment wall
  • Zero-valent iron

ASJC Scopus subject areas

  • Environmental Chemistry
  • Waste Management and Disposal
  • Pollution

Cite this

Abiotic degradation of nitrates using zero-valent iron and electrokinetic processes. / Chew, Chin F.; Zhang, Tian C.

In: Environmental Engineering Science, Vol. 16, No. 5, 01.01.1999, p. 389-401.

Research output: Contribution to journalArticle

@article{0a1c4cb6909d42eea59c87e0fc708522,
title = "Abiotic degradation of nitrates using zero-valent iron and electrokinetic processes",
abstract = "Nitrate transformation in artificial saturated soils made from sand and/or clay mixed with nitrate-contaminated water was investigated using (1) zero-valent iron treatment, (2) electrokinetics treatment alone, and (3) electrokinetics coupled with an iron treatment wall placed near the cathode or anode. Approximately 75-98{\%} of the nitrates were transformed using zero- valent iron to treat the artificial soils. The major products in the zero- valent-assisted transformation were nitrogen gases (75-81{\%}) and ammonia- nitrogen (2-18{\%}). Nitrite-nitrogen was less than 1{\%} in all these experiments. With electrokinetics alone, some nitrates were transformed (about 30{\%}). Nitrate transformation was about 60{\%} with the iron wall placed near the cathode, and was about 95{\%} with the iron wall placed near the anode. The major products were nitrogen gases and ammonia. Nitrite-nitrogen was less than 1{\%} in these runs. Electroosmotic permeability (Ke) variation appeared to be dependent on the voltage in the reactor. The pH variations over time in electrokinetics (control and iron wall near cathode) indicated the movement of a small acid front. However, the presence of an iron wall near the anode tended to increase the pH slightly. The pH variations over time in the electrokinetics coupled with an iron wall depend on the location of the iron wall. This study demonstrates that electrokinetics coupled with an iron wall near the anode is capable of remediating nitrate contamination in low permeability soils.",
keywords = "Electrokinetics, Groundwater remediation, Nitrates, Treatment wall, Zero-valent iron",
author = "Chew, {Chin F.} and Zhang, {Tian C.}",
year = "1999",
month = "1",
day = "1",
doi = "10.1089/ees.1999.16.389",
language = "English (US)",
volume = "16",
pages = "389--401",
journal = "Environmental Engineering Science",
issn = "1092-8758",
publisher = "Mary Ann Liebert Inc.",
number = "5",

}

TY - JOUR

T1 - Abiotic degradation of nitrates using zero-valent iron and electrokinetic processes

AU - Chew, Chin F.

AU - Zhang, Tian C.

PY - 1999/1/1

Y1 - 1999/1/1

N2 - Nitrate transformation in artificial saturated soils made from sand and/or clay mixed with nitrate-contaminated water was investigated using (1) zero-valent iron treatment, (2) electrokinetics treatment alone, and (3) electrokinetics coupled with an iron treatment wall placed near the cathode or anode. Approximately 75-98% of the nitrates were transformed using zero- valent iron to treat the artificial soils. The major products in the zero- valent-assisted transformation were nitrogen gases (75-81%) and ammonia- nitrogen (2-18%). Nitrite-nitrogen was less than 1% in all these experiments. With electrokinetics alone, some nitrates were transformed (about 30%). Nitrate transformation was about 60% with the iron wall placed near the cathode, and was about 95% with the iron wall placed near the anode. The major products were nitrogen gases and ammonia. Nitrite-nitrogen was less than 1% in these runs. Electroosmotic permeability (Ke) variation appeared to be dependent on the voltage in the reactor. The pH variations over time in electrokinetics (control and iron wall near cathode) indicated the movement of a small acid front. However, the presence of an iron wall near the anode tended to increase the pH slightly. The pH variations over time in the electrokinetics coupled with an iron wall depend on the location of the iron wall. This study demonstrates that electrokinetics coupled with an iron wall near the anode is capable of remediating nitrate contamination in low permeability soils.

AB - Nitrate transformation in artificial saturated soils made from sand and/or clay mixed with nitrate-contaminated water was investigated using (1) zero-valent iron treatment, (2) electrokinetics treatment alone, and (3) electrokinetics coupled with an iron treatment wall placed near the cathode or anode. Approximately 75-98% of the nitrates were transformed using zero- valent iron to treat the artificial soils. The major products in the zero- valent-assisted transformation were nitrogen gases (75-81%) and ammonia- nitrogen (2-18%). Nitrite-nitrogen was less than 1% in all these experiments. With electrokinetics alone, some nitrates were transformed (about 30%). Nitrate transformation was about 60% with the iron wall placed near the cathode, and was about 95% with the iron wall placed near the anode. The major products were nitrogen gases and ammonia. Nitrite-nitrogen was less than 1% in these runs. Electroosmotic permeability (Ke) variation appeared to be dependent on the voltage in the reactor. The pH variations over time in electrokinetics (control and iron wall near cathode) indicated the movement of a small acid front. However, the presence of an iron wall near the anode tended to increase the pH slightly. The pH variations over time in the electrokinetics coupled with an iron wall depend on the location of the iron wall. This study demonstrates that electrokinetics coupled with an iron wall near the anode is capable of remediating nitrate contamination in low permeability soils.

KW - Electrokinetics

KW - Groundwater remediation

KW - Nitrates

KW - Treatment wall

KW - Zero-valent iron

UR - http://www.scopus.com/inward/record.url?scp=0032824705&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0032824705&partnerID=8YFLogxK

U2 - 10.1089/ees.1999.16.389

DO - 10.1089/ees.1999.16.389

M3 - Article

AN - SCOPUS:0032824705

VL - 16

SP - 389

EP - 401

JO - Environmental Engineering Science

JF - Environmental Engineering Science

SN - 1092-8758

IS - 5

ER -