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Development and Validation of Chromium Getters for Solid Oxide Fuel Cell Power Systems
Published on: May 26, 2019
Sonoassisted microbial reduction of chromium
Mathur Nadarajan Kathiravan1, Ramalingam Karthick, Naggapan Muthu
1Department of Chemical Engineering, A.C. College of Technology, Anna University, Chennai 600025, India.
Applied Biochemistry and Biotechnology
|July 29, 2009
Summary
This study demonstrates ultrasound-assisted microbial reduction of toxic hexavalent chromium (Cr(VI)) using Bacillus sp. This method enhances chromium removal efficiency from contaminated sites.
Area of Science:
- Environmental Microbiology
- Bioremediation
- Applied Microbiology
Background:
- Hexavalent chromium (Cr(VI)) is a toxic pollutant commonly found in tannery effluents.
- Microbial reduction offers a promising bioremediation strategy for Cr(VI) contamination.
- Sono-assisted processes can enhance microbial activity and pollutant degradation.
Purpose of the Study:
- To investigate the sonoassisted microbial reduction of Cr(VI) using Bacillus sp.
- To determine optimal conditions for Cr(VI) reduction.
- To analyze the impact of ultrasound on microbial Cr(VI) reduction efficiency.
Main Methods:
- Isolation and characterization of Bacillus sp. from tannery effluent.
- Microbial Cr(VI) reduction experiments in the presence and absence of ultrasound.
- Optimization of pH, temperature, electron donors, biomass, and initial Cr(VI) concentration.
- Fourier-transform infrared spectroscopy (FTIR) for analyzing functional group changes.
- Modeling microbial growth using Monod and Andrews models.
Main Results:
- Optimal Cr(VI) reduction by Bacillus sp. occurred at pH 7.0 and 37°C.
- Glucose was identified as the most effective electron donor.
- Ultrasound irradiation significantly enhanced Cr(VI) reduction efficiency.
- Cr(VI) reduction increased with biomass concentration but decreased with higher initial Cr(VI) levels.
- FTIR spectra indicated changes in Bacillus sp. functional groups post-chromium reduction.
- The Andrews model provided the best fit for microbial growth kinetics.
Conclusions:
- Sonoassisted microbial reduction using Bacillus sp. is an effective method for Cr(VI) remediation.
- Optimized conditions and ultrasound application maximize bioremediation potential.
- Understanding microbial and process dynamics is crucial for efficient chromium removal.
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