Citation
(2009), "Corrosion-inhibiting coatings containing “Good bacteria", Pigment & Resin Technology, Vol. 38 No. 5. https://doi.org/10.1108/prt.2009.12938ead.010
Publisher
:Emerald Group Publishing Limited
Copyright © 2009, Emerald Group Publishing Limited
Corrosion-inhibiting coatings containing “Good bacteria
Article Type: New products From: Pigment & Resin Technology, Volume 38, Issue 5
A new, environmentally friendly coating that protects metals against corrosion in seawater has been developed by a team of researchers from Sheffield Hallam University.
At the Society for General Microbiology meeting in Harrogate March 30, Jeanette Gittens and colleagues described how they had encapsulated spores from a bacterium into a sol-gel coating which then protected an aluminium alloy from microbial corrosion.
Microbially influenced corrosion of metals at sea is a big safety and financial problem caused by the production of damaging substances such as hydrogen sulphide by sulphate-reducing micro-organisms within biofilms on the surfaces. Overall, it is estimated that corrosion costs the UK around 3-4 percent of GDP. Existing anti-corrosion treatments are costly, ineffective and often include biocides and inhibitors that are toxic to aquatic life.
The corrosion-preventing bacteria occur naturally in the environment. Incorporating its spores into the coating did not seem to affect their viability – living cells were still found in the coating after more than six weeks in seawater. The coating could also be heat cured at temperatures up to 90°C.
Speaking at the meeting, Ms Gittens said, “Our results from laboratory studies and a field trial in the Thames estuary have shown that the bacteria-containing coating is substantially more effective in the prevention of corrosion than the sol-only coating. We are investigating what causes the corrosion protection – we think it might be due to the immobilized bacteria producing antimicrobial agents which inhibit the growth of corrosion-causing microorganisms.”
Additional trials are now planned or in progress in a variety of marine environments.