Corrosion behaviour of copper under biotic and abiotic conditions in anoxic ground water

electrochemical study

Research output: Contribution to journalArticleScientificpeer-review

14 Citations (Scopus)

Abstract

Finnish nuclear waste disposal program proposes to dispose spent nuclear fuel in tightly sealed copper canisters in a geological repository; here, copper acts as a corrosion barrier. The key argument for such materials selection is that copper is resistant to corrosion in oxygen-free water. However, the presence and colonization of microbial species in ground water in the geological repository may initiate, facilitate and accelerate corrosion of copper under such conditions. In this study, the results from experiments that were designed to simulate the final stage of the deep geological nuclear waste repository, when the temperature has already stabilized to the level of the surrounding bedrock and all oxygen included at the construction stage has been consumed, are reported, both in the presence and absence of micro-organisms retrieved from the repository site. The experiments were performed for 10 months, during which the copper specimens were subjected to electrochemical measurements. After the tests, the specimens were investigated in terms of microstructure and weight changes, while the test media was characterized with respect to selected chemical species. Analysis concentrated on EIS data in the light of results obtained by other methods. In the presence of micro-organisms, e.g., sulphate-reducing bacteria, the development of Cu2S is the primary surface process on copper specimens, with its corrosion protection properties being regulated by the growth of the biofilm. As compared to two-layered Cu2O films that grow on the specimen surfaces in the absence of bacteria, Cu2S films were essentially less susceptible for the attack by Cl-. Under abiotic conditions, passivity breakdown by Cl- resulting in the localized type of attack detected on the surfaces is the probable reason for an essentially higher corrosion rate than in the biotic system.
Original languageEnglish
Pages (from-to)350-365
JournalElectrochimica Acta
Volume203
DOIs
Publication statusPublished - 2016
MoE publication typeA1 Journal article-refereed

Fingerprint

Copper
Groundwater
Corrosion
Geological repositories
Radioactive Waste
Radioactive wastes
Bacteria
Oxygen
Spent fuels
Nuclear fuels
Biofilms
Corrosion protection
Corrosion rate
Waste disposal
Sulfates
Experiments
Microstructure
Water
Temperature

Keywords

  • bacteria
  • copper
  • corrosion
  • electrochemical impedance spectroscopy
  • geological repositories
  • geology
  • groundwater
  • microorganisms
  • radioactive waste disposal
  • radioactive wastes
  • waste disposal
  • construction stages
  • electrochemical measurements
  • electrochemical studies
  • microbially induced corrosions
  • nuclear waste disposal
  • nuclear waste repositories
  • passivity breakdown
  • sulphate-reducing bacteria

Cite this

@article{8e320b71664f4529b2ccc079c0b67edc,
title = "Corrosion behaviour of copper under biotic and abiotic conditions in anoxic ground water: electrochemical study",
abstract = "Finnish nuclear waste disposal program proposes to dispose spent nuclear fuel in tightly sealed copper canisters in a geological repository; here, copper acts as a corrosion barrier. The key argument for such materials selection is that copper is resistant to corrosion in oxygen-free water. However, the presence and colonization of microbial species in ground water in the geological repository may initiate, facilitate and accelerate corrosion of copper under such conditions. In this study, the results from experiments that were designed to simulate the final stage of the deep geological nuclear waste repository, when the temperature has already stabilized to the level of the surrounding bedrock and all oxygen included at the construction stage has been consumed, are reported, both in the presence and absence of micro-organisms retrieved from the repository site. The experiments were performed for 10 months, during which the copper specimens were subjected to electrochemical measurements. After the tests, the specimens were investigated in terms of microstructure and weight changes, while the test media was characterized with respect to selected chemical species. Analysis concentrated on EIS data in the light of results obtained by other methods. In the presence of micro-organisms, e.g., sulphate-reducing bacteria, the development of Cu2S is the primary surface process on copper specimens, with its corrosion protection properties being regulated by the growth of the biofilm. As compared to two-layered Cu2O films that grow on the specimen surfaces in the absence of bacteria, Cu2S films were essentially less susceptible for the attack by Cl-. Under abiotic conditions, passivity breakdown by Cl- resulting in the localized type of attack detected on the surfaces is the probable reason for an essentially higher corrosion rate than in the biotic system.",
keywords = "bacteria, copper, corrosion, electrochemical impedance spectroscopy, geological repositories, geology, groundwater, microorganisms, radioactive waste disposal, radioactive wastes, waste disposal, construction stages, electrochemical measurements, electrochemical studies, microbially induced corrosions, nuclear waste disposal, nuclear waste repositories, passivity breakdown, sulphate-reducing bacteria",
author = "Elina Huttunen-Saarivirta and Pauliina Rajala and Carp{\'e}n, {Leena I.}",
year = "2016",
doi = "10.1016/j.electacta.2016.01.098",
language = "English",
volume = "203",
pages = "350--365",
journal = "Electrochimica Acta",
issn = "0013-4686",
publisher = "Elsevier",

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TY - JOUR

T1 - Corrosion behaviour of copper under biotic and abiotic conditions in anoxic ground water

T2 - electrochemical study

AU - Huttunen-Saarivirta, Elina

AU - Rajala, Pauliina

AU - Carpén, Leena I.

PY - 2016

Y1 - 2016

N2 - Finnish nuclear waste disposal program proposes to dispose spent nuclear fuel in tightly sealed copper canisters in a geological repository; here, copper acts as a corrosion barrier. The key argument for such materials selection is that copper is resistant to corrosion in oxygen-free water. However, the presence and colonization of microbial species in ground water in the geological repository may initiate, facilitate and accelerate corrosion of copper under such conditions. In this study, the results from experiments that were designed to simulate the final stage of the deep geological nuclear waste repository, when the temperature has already stabilized to the level of the surrounding bedrock and all oxygen included at the construction stage has been consumed, are reported, both in the presence and absence of micro-organisms retrieved from the repository site. The experiments were performed for 10 months, during which the copper specimens were subjected to electrochemical measurements. After the tests, the specimens were investigated in terms of microstructure and weight changes, while the test media was characterized with respect to selected chemical species. Analysis concentrated on EIS data in the light of results obtained by other methods. In the presence of micro-organisms, e.g., sulphate-reducing bacteria, the development of Cu2S is the primary surface process on copper specimens, with its corrosion protection properties being regulated by the growth of the biofilm. As compared to two-layered Cu2O films that grow on the specimen surfaces in the absence of bacteria, Cu2S films were essentially less susceptible for the attack by Cl-. Under abiotic conditions, passivity breakdown by Cl- resulting in the localized type of attack detected on the surfaces is the probable reason for an essentially higher corrosion rate than in the biotic system.

AB - Finnish nuclear waste disposal program proposes to dispose spent nuclear fuel in tightly sealed copper canisters in a geological repository; here, copper acts as a corrosion barrier. The key argument for such materials selection is that copper is resistant to corrosion in oxygen-free water. However, the presence and colonization of microbial species in ground water in the geological repository may initiate, facilitate and accelerate corrosion of copper under such conditions. In this study, the results from experiments that were designed to simulate the final stage of the deep geological nuclear waste repository, when the temperature has already stabilized to the level of the surrounding bedrock and all oxygen included at the construction stage has been consumed, are reported, both in the presence and absence of micro-organisms retrieved from the repository site. The experiments were performed for 10 months, during which the copper specimens were subjected to electrochemical measurements. After the tests, the specimens were investigated in terms of microstructure and weight changes, while the test media was characterized with respect to selected chemical species. Analysis concentrated on EIS data in the light of results obtained by other methods. In the presence of micro-organisms, e.g., sulphate-reducing bacteria, the development of Cu2S is the primary surface process on copper specimens, with its corrosion protection properties being regulated by the growth of the biofilm. As compared to two-layered Cu2O films that grow on the specimen surfaces in the absence of bacteria, Cu2S films were essentially less susceptible for the attack by Cl-. Under abiotic conditions, passivity breakdown by Cl- resulting in the localized type of attack detected on the surfaces is the probable reason for an essentially higher corrosion rate than in the biotic system.

KW - bacteria

KW - copper

KW - corrosion

KW - electrochemical impedance spectroscopy

KW - geological repositories

KW - geology

KW - groundwater

KW - microorganisms

KW - radioactive waste disposal

KW - radioactive wastes

KW - waste disposal

KW - construction stages

KW - electrochemical measurements

KW - electrochemical studies

KW - microbially induced corrosions

KW - nuclear waste disposal

KW - nuclear waste repositories

KW - passivity breakdown

KW - sulphate-reducing bacteria

U2 - 10.1016/j.electacta.2016.01.098

DO - 10.1016/j.electacta.2016.01.098

M3 - Article

VL - 203

SP - 350

EP - 365

JO - Electrochimica Acta

JF - Electrochimica Acta

SN - 0013-4686

ER -