Celebrate World Corrosion Awareness Day with 20% off eCourses and eBooks with code WCAD2024 at checkout!
Zinc and its alloys are used as sacrificial anodes because zinc is an active metal. Carbon steel can be coated with zinc to protect against corrosion. These metals are known as galvanized steel. In this work, microbiologically influenced corrosion (MIC) of pure zinc and galvanized steel caused by a sulfate reducing bacterium was investigated. After 7 days of incubation in 125 mL anaerobic vials with 100 mL culture medium and 1 mL inoculum, the sessile cell count on the galvanized steel was slightly higher than that on pure zinc. The abiotic weight loss for pure zinc was 1.4 ± 0.1 mg/cm2 vs. 4.6 ± 0.1 mg/cm2 for galvanized steel after 7 days of anaerobic incubation at 37oC. The weight losses for galvanized steel and pure zinc were 31.5 ± 2.5 mg/cm2 and 35.4 ± 4.5 mg/cm2, respectively, which were 10X larger than the previously reported carbon steel weight loss in the same SRB broth. Electrochemical corrosion tests confirmed the severe corrosion of these two metals. The corrosion current densities of galvanized and pure zinc were 25.5 µA/cm2 and 100 µA/cm2, respectô€€€vely at the end of the 7-day incubation with SRB, confirming that pure zinc was more prone to SRB MIC than galvanized steel. In both cases, the corrosion product was mainly ZnS. Three MIC mechanisms were possible for the severe corrosion. Extracellular electron transfer MIC is thermodynamically favorable for Zn. Furthermore, the detection of H2 evolution in the vials suggest that proton attack and H2S attack occurred against Zn in the SRB broth with neutral pH after passive film damage by the SRB biofilm.
Standard test method for microbiologically influenced corrosion (MIC) on internal surfaces of pipelines. Types of microorganisms, MIC mechanisms, sampling and testing. Research results, and interpretation of test.
We are unable to complete this action. Please try again at a later time.
If this error continues to occur, please contact AMPP Customer Support for assistance.
Use this error code for reference:
Please login to use Standards Credits*
* AMPP Members receive Standards Credits in order to redeem eligible Standards and Reports in the Store
You are not a Member.
AMPP Members enjoy many benefits, including Standards Credits which can be used to redeem eligible Standards and Reports in the Store.
You can visit the Membership Page to learn about the benefits of membership.
You have previously purchased this item.
Go to Downloadable Products in your AMPP Store profile to find this item.
You do not have sufficient Standards Credits to claim this item.
Click on 'ADD TO CART' to purchase this item.
Your Standards Credit(s)
1
Remaining Credits
0
Please review your transaction.
Click on 'REDEEM' to use your Standards Credits to claim this item.
You have successfully redeemed:
Go to Downloadable Products in your AMPP Store Profile to find and download this item.
Types of microorganisms and mechanisms by which MIC occurs on external surfaces of buried, ferrous-based metal pipelines. Testing for the presence of bacteria, research results, and interpretation.