1
|
Chen Y, Zhou H, Gao H, Su Z, Li X, Qi P, Li T, Hu C, Li Z, Bi Z, Xing X, Yang J, Chen C, Ma K, Chen J. Comprehensive comparison of water quality risk and microbial ecology between new and old cast iron pipe distribution systems. J Environ Sci (China) 2024; 146:55-66. [PMID: 38969462 DOI: 10.1016/j.jes.2023.05.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2023] [Revised: 05/11/2023] [Accepted: 05/12/2023] [Indexed: 07/07/2024]
Abstract
The effects of cast iron pipe corrosion on water quality risk and microbial ecology in drinking water distribution systems (DWDSs) were investigated. It was found that trihalomethane (THMs) concentration and antibiotic resistance genes (ARGs) increased sharply in the old DWDSs. Under the same residual chlorine concentration conditions, the adenosine triphosphate concentration in the effluent of old DWDSs (Eff-old) was significantly higher than that in the effluent of new DWDSs. Moreover, stronger bioflocculation ability and weaker hydrophobicity coexisted in the extracellular polymeric substances of Eff-old, meanwhile, iron particles could be well inserted into the structure of the biofilms to enhance the mechanical strength and stability of the biofilms, hence enhancing the formation of THMs. Old DWDSs significantly influenced the microbial community of bulk water and triggered stronger microbial antioxidant systems response, resulting in higher ARGs abundance. Corroded cast iron pipes induced a unique interaction system of biofilms, chlorine, and corrosion products. Therefore, as the age of cast iron pipes increases, the fluctuation of water quality and microbial ecology should be paid more attention to maintain the safety of tap water.
Collapse
Affiliation(s)
- Youyi Chen
- Institute of Environmental Research at Greater Bay, Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou 510006, China
| | - Huishan Zhou
- Institute of Environmental Research at Greater Bay, Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou 510006, China
| | - Hui Gao
- Zhejiang Xingtuo Ecological Environment Co., Ltd., Hangzhou 310051, China
| | - Ziliang Su
- Institute of Environmental Research at Greater Bay, Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou 510006, China
| | - Xinjun Li
- Institute of Environmental Research at Greater Bay, Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou 510006, China
| | - Peng Qi
- Institute of Environmental Research at Greater Bay, Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou 510006, China
| | - Tong Li
- Institute of Environmental Research at Greater Bay, Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou 510006, China
| | - Chun Hu
- Institute of Environmental Research at Greater Bay, Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou 510006, China
| | - Zesong Li
- Institute of Environmental Research at Greater Bay, Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou 510006, China
| | - Zhihao Bi
- Institute of Environmental Research at Greater Bay, Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou 510006, China
| | - Xueci Xing
- Institute of Environmental Research at Greater Bay, Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou 510006, China.
| | - Jingxin Yang
- Institute of Environmental Research at Greater Bay, Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou 510006, China
| | - Chaoxiang Chen
- Nanzhou Waterworks of Guangzhou Water Supply Co. Ltd., Guangzhou 510000, China
| | - Kunyu Ma
- Nanzhou Waterworks of Guangzhou Water Supply Co. Ltd., Guangzhou 510000, China
| | - Jinrong Chen
- Nanzhou Waterworks of Guangzhou Water Supply Co. Ltd., Guangzhou 510000, China
| |
Collapse
|
2
|
Liu Y, Zhang Z, Song Y, Peng F, Feng Y. Long-term evaluating the strengthening effects of iron-carbon mediator for coking wastewater treatment in EGSB reactor. JOURNAL OF HAZARDOUS MATERIALS 2024; 474:134701. [PMID: 38824774 DOI: 10.1016/j.jhazmat.2024.134701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2024] [Revised: 05/05/2024] [Accepted: 05/21/2024] [Indexed: 06/04/2024]
Abstract
Coking wastewater (CWW) treatment is difficult due to its complex composition and high biological toxicity. Iron-carbon mediators was used to enhance the treatment of CWW through iron-carbon microelectrolysis (ICME). The results indicated that the removal rate of COD and phenolic compounds were enhanced by 24.1 % and 23.5 %, while biogas production and methane content were promoted by 50 % and 7 %. Microbial community analysis indicated that iron-carbon mediators had a transformative impact on the reactor's performance and dependability by enriching microorganisms involved in direct and indirect electron transfer, such as Anaerolineae and Methanothrix. The mediator also produced noteworthy gains in LB-EPS and TB-EPS, increasing by roughly 109.3 % and 211.6 %, respectively. PICRISt analysis demonstrated that iron-carbon mediators effectively augment the abundance of functional genes associated with metabolism, Citrate cycle, and EET pathway. This study provides a new approach for CWW treatment.
Collapse
Affiliation(s)
- Yanbo Liu
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, No73, Huanghe Road, Nangang District, Harbin 150090, China
| | - Zhaohan Zhang
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, No73, Huanghe Road, Nangang District, Harbin 150090, China.
| | - Yanfang Song
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, No73, Huanghe Road, Nangang District, Harbin 150090, China
| | - Fangyue Peng
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, No73, Huanghe Road, Nangang District, Harbin 150090, China
| | - Yujie Feng
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, No73, Huanghe Road, Nangang District, Harbin 150090, China.
| |
Collapse
|
3
|
Zhou X, Wang Q, Su H, Tan Z, Li C, Li Z, Wu T. Low efficiency of cathodic protection in marine tidal corrosion of X80 steel in the presence of Pseudomonas sp. Bioelectrochemistry 2024; 157:108656. [PMID: 38290303 DOI: 10.1016/j.bioelechem.2024.108656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Revised: 01/20/2024] [Accepted: 01/23/2024] [Indexed: 02/01/2024]
Abstract
Owing to the effects of seawater erosion, dry/wet cycles, dissolved oxygen and microorganisms, the corrosion of steel in marine tidal environments is a serious threat to the safe and stable operation of marine equipment and facilities. Among them, microbiologically influenced corrosion (MIC) of steel has received increasing attention. Cathodic protection (CP) is frequently used to control the corrosion of offshore steel structures. However, in the presence of microorganisms, implementation of CP and its specific effects remain controversial. In this study, the influence of Pseudomonas sp. on the CP efficiency of Zn sacrificial anodes (ZnSAs) during the tidal corrosion of X80 steel was studied. The results showed that CP efficiency exceeded 92% in an abiotic tidal environment. However, in the biotic tidal environment, Pseudomonas sp. significantly reduced the CP efficiency. Pseudomonas sp. and its biofilm promoted the corrosion of steel under CP, inhibited the formation of a complete calcareous deposit layer, which weakened the CP efficiency of ZnSA in the marine tidal environment.
Collapse
Affiliation(s)
- Xiaobao Zhou
- School of Materials Science and Engineering, Xiangtan University, Xiangtan 411105, China
| | - Qin Wang
- School of Materials Science and Engineering, Xiangtan University, Xiangtan 411105, China
| | - Hui Su
- School of Materials Science and Engineering, Xiangtan University, Xiangtan 411105, China
| | - Zhuowei Tan
- School of Materials Science and Engineering, Xiangtan University, Xiangtan 411105, China
| | - Cong Li
- School of Materials Science and Engineering, Xiangtan University, Xiangtan 411105, China
| | - Zhi Li
- School of Materials Science and Engineering, Xiangtan University, Xiangtan 411105, China.
| | - Tangqing Wu
- School of Materials Science and Engineering, Xiangtan University, Xiangtan 411105, China.
| |
Collapse
|
4
|
Zou JJ, Dai C, Hu J, Tong WK, Gao MT, Zhang Y, Leong KH, Fu R, Zhou L. A novel mycelial pellet applied to remove polycyclic aromatic hydrocarbons: High adsorption performance & its mechanisms. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 922:171201. [PMID: 38417506 DOI: 10.1016/j.scitotenv.2024.171201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Revised: 02/06/2024] [Accepted: 02/21/2024] [Indexed: 03/01/2024]
Abstract
Mycelial pellets formed by Penicillium thomii ZJJ were applied as efficient biosorbents for the removal of polycyclic aromatic hydrocarbons (PAHs), which are a type of ubiquitous harmful hydrophobic pollutants. The live mycelial pellets were able to remove 93.48 % of pyrene at a concentration of 100 mg/L within 48 h, demonstrating a maximum adsorption capacity of 285.63 mg/g. Meanwhile, the heat-killed one also achieved a removal rate of 65.01 %. Among the six typical PAHs (pyrene, phenanthrene, fluorene, anthracene, fluoranthene, benzo[a]pyrene), the mycelial pellets preferentially adsorbed the high molecular weight PAHs, which also have higher toxicity, resulting in higher removal efficiency. The experimental results showed that the biosorption of mycelial pellets was mainly a spontaneous physical adsorption process that occurred as a monolayer on a homogeneous surface, with mass transfer being the key rate-limiting step. The main adsorption sites on the surface of mycelia were carboxyl and N-containing groups. Extracellular polymeric substances (EPS) produced by mycelial pellets could enhance adsorption, and its coupling with dead mycelia could achieve basically the same removal effect to that of living one. It can be concluded that biosorption by mycelial pellets occurred due to the influence of electrostatic and hydrophobic interactions, consisting of five steps. Furthermore, the potential applicability of mycelial pellets has been investigated considering diverse factors. The mycelia showed high environmental tolerance, which could effectively remove pyrene across a wide range of pH and salt concentration. And pellets diameters and humic acid concentration had a significant effect on microbial adsorption effect. Based on a cost-effectiveness analysis, mycelium pellets were found to be a low-cost adsorbent. The research outcomes facilitate a thorough comprehension of the adsorption process of pyrene by mycelial pellets and their relevant applications, proposing a cost-effective method without potential environmental issues (heat-killed mycelial pellets plus EPS) to removal PAHs.
Collapse
Affiliation(s)
- Jia Jie Zou
- College of Civil Engineering, Tongji University, Shanghai 200092, China; Shanghai Key Laboratory of Bio-Energy Crops, School of Life Sciences, Shanghai University, Shanghai 200444, China
| | - Chaomeng Dai
- College of Civil Engineering, Tongji University, Shanghai 200092, China.
| | - Jiajun Hu
- Shanghai Key Laboratory of Bio-Energy Crops, School of Life Sciences, Shanghai University, Shanghai 200444, China.
| | - Wang Kai Tong
- College of Civil Engineering, Tongji University, Shanghai 200092, China; Shanghai Key Laboratory of Bio-Energy Crops, School of Life Sciences, Shanghai University, Shanghai 200444, China
| | - Min-Tian Gao
- Shanghai Key Laboratory of Bio-Energy Crops, School of Life Sciences, Shanghai University, Shanghai 200444, China
| | - Yalei Zhang
- College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Kah Hon Leong
- Department of Environmental Engineering, Faculty of Engineering and Green Technology, University Tunku Abdul Rahman, 31900 Kampar, Perak, Malaysia
| | - Rongbing Fu
- College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Lang Zhou
- Department of Civil, Architectural and Environmental Engineering, University of Texas at Austin, Austin, TX 78712, United States
| |
Collapse
|
5
|
Hao S, Qi Y, Zhang Z. Influence of Light Conditions on the Antibacterial Performance and Mechanism of Waterborne Fluorescent Coatings Based on Waterproof Long Afterglow Phosphors/PDMS Composites. Polymers (Basel) 2023; 15:3873. [PMID: 37835922 PMCID: PMC10574996 DOI: 10.3390/polym15193873] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Revised: 09/18/2023] [Accepted: 09/22/2023] [Indexed: 10/15/2023] Open
Abstract
Marine microbial adhesion is the fundamental cause of large-scale biological fouling. Low surface energy coatings can prevent marine installations from biofouling; nevertheless, their static antifouling abilities are limited in the absence of shear forces produced by seawater. Novel waterborne antifouling coatings inspired by fluorescent coral were reported in this paper. Waterproof long afterglow phosphors (WLAP) were introduced into waterborne silicone elastomers by the physical blending method. The composite coatings store energy during the day, and the various colors of light emitted at night affect the regular physiological activities of marine bacteria. Due to the synergistic effect of fouling-release and fluorescence antifouling, the WLAP/polydimethylsiloxane (PDMS) composite coating showed excellent antifouling abilities. The antibacterial performance of coatings was tested under simulated day-night alternation, continuous light, and constant dark conditions, respectively. The results illustrated that the antibacterial performance of composite coatings under simulated day-night alternation conditions was significantly better than that under continuous light or darkness. The weak lights emitted by the coating can effectively inhibit the adhesion of bacteria. C-SB/PDMS showed the best antibacterial effect, with a bacterial adhesion rate (BAR) of only 3.7%. Constant strong light also affects the normal physiological behavior of bacteria, and the weak light of coatings was covered. The antibacterial ability of coatings primarily relied on their surface properties under continuous dark conditions. The fluorescent effect played a vital role in the synergetic antifouling mechanism. This study enhanced the static antifouling abilities of coatings and provided a new direction for environmentally friendly and long-acting marine antifouling coatings.
Collapse
Affiliation(s)
- Sinan Hao
- Key Laboratory of Ship-Machinery Maintenance & Manufacture, Dalian Maritime University, Dalian 116026, China; (S.H.); (Z.Z.)
- Department of Materials Science and Engineering, Dalian Maritime University, Dalian 116026, China
| | - Yuhong Qi
- Key Laboratory of Ship-Machinery Maintenance & Manufacture, Dalian Maritime University, Dalian 116026, China; (S.H.); (Z.Z.)
- Department of Materials Science and Engineering, Dalian Maritime University, Dalian 116026, China
| | - Zhanping Zhang
- Key Laboratory of Ship-Machinery Maintenance & Manufacture, Dalian Maritime University, Dalian 116026, China; (S.H.); (Z.Z.)
- Department of Materials Science and Engineering, Dalian Maritime University, Dalian 116026, China
| |
Collapse
|
6
|
Liang L, Ren Y, Tian Y, Garcí JAA, Zhang P, Zhu X. Role of Pseudomonas fluorescens FSYZ01 on the corrosion behavior of Q235B carbon steel in oilfield produced water. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:62590-62601. [PMID: 36947376 DOI: 10.1007/s11356-023-26446-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Accepted: 03/10/2023] [Indexed: 05/10/2023]
Abstract
The corrosion behavior of Q235B carbon steel is investigated in water, LB medium, and oilfield produced water adding Pseudomonas fluorescens FSYZ01. After immersion at 30 °C for 13 days, the weight loss of carbon steel with this strain decreased by 32.23%, 54.07%, and 78.34%, respectively. X-ray diffraction (XRD) results show that P. fluorescens FSYZ01 inhibited conversion of iron oxides by hindering oxygen from approaching metal surface. Fourier transform infrared (FT-IR) and X-ray photoelectron spectrometer (XPS) results show that specific functional groups and bonds reacted with Fe(II/III) to form a dense and stable chelate-oxide protective layer, thereby inhibiting corrosion. Pyrolysis gas chromatography-mass spectrometer (Py-GCMS) results demonstrate the bacteria degraded C12 to C20 alkanes in oil. The inhibitory mechanism of crude oil-degrading bacteria P. fluorescens FSYZ01 on the carbon steel corrosion was proposed, so as to slow corrosion of oilfield produced water system pipeline and prolong its service life, helping to comprehend the microbial corrosion in the actual environment.
Collapse
Affiliation(s)
- Lihua Liang
- College of Urban and Environmental Science, Northwest University, Xi'an, 710127, China.
- Shaanxi Key Laboratory of Earth Surface System and Environmental Carrying Capacity, Xi'an, China.
| | - Yuanyuan Ren
- College of Urban and Environmental Science, Northwest University, Xi'an, 710127, China
| | - Yuan Tian
- Changqing Engineering Design Co., Ltd., Xi'an, 710018, China
| | | | - Pu Zhang
- International Center for Planetary Science College of Earth Sciences, Chengdu University of Technology, Chengdu, 610059, China
| | - Xiaoli Zhu
- College of Urban and Environmental Science, Northwest University, Xi'an, 710127, China
- Shaanxi Key Laboratory of Earth Surface System and Environmental Carrying Capacity, Xi'an, China
| |
Collapse
|
7
|
Yang K, Bu H, Zhang Y, Yu H, Huang S, Ke L, Hong P. Efficacy of simultaneous hexavalent chromium biosorption and nitrogen removal by the aerobic denitrifying bacterium Pseudomonas stutzeri YC-34 from chromium-rich wastewater. Front Microbiol 2022; 13:961815. [PMID: 35992714 PMCID: PMC9389319 DOI: 10.3389/fmicb.2022.961815] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2022] [Accepted: 07/11/2022] [Indexed: 12/03/2022] Open
Abstract
The impact of high concentrations of heavy metals and the loss of functional microorganisms usually affect the nitrogen removal process in wastewater treatment systems. In the study, a unique auto-aggregating aerobic denitrifier (Pseudomonas stutzeri strain YC-34) was isolated with potential applications for Cr(VI) biosorption and reduction. The nitrogen removal efficiency and denitrification pathway of the strain were determined by measuring the concentration changes of inorganic nitrogen during the culture of the strain and amplifying key denitrification functional genes. The changes in auto-aggregation index, hydrophobicity index, and extracellular polymeric substances (EPS) characteristic index were used to evaluate the auto-aggregation capacity of the strain. Further studies on the biosorption ability and mechanism of cadmium in the process of denitrification were carried out. The changes in tolerance and adsorption index of cadmium were measured and the micro-characteristic changes on the cell surface were analyzed. The strain exhibited excellent denitrification ability, achieving 90.58% nitrogen removal efficiency with 54 mg/L nitrate-nitrogen as the initial nitrogen source and no accumulation of ammonia and nitrite-nitrogen. Thirty percentage of the initial nitrate-nitrogen was converted to N2, and only a small amount of N2O was produced. The successful amplification of the denitrification functional genes, norS, norB, norR, and nosZ, further suggested a complete denitrification pathway from nitrate to nitrogen. Furthermore, the strain showed efficient aggregation capacity, with the auto-aggregation and hydrophobicity indices reaching 78.4 and 75.5%, respectively. A large amount of protein-containing EPS was produced. In addition, the strain effectively removed 48.75, 46.67, 44.53, and 39.84% of Cr(VI) with the initial concentrations of 3, 5, 7, and 10 mg/L, respectively, from the nitrogen-containing synthetic wastewater. It also could reduce Cr(VI) to the less toxic Cr(III). FTIR measurements and characteristic peak deconvolution analysis demonstrated that the strain had a robust hydrogen-bonded structure with strong intermolecular forces under the stress of high Cr(VI) concentrations. The current results confirm that the novel denitrifier can simultaneously remove nitrogen and chromium and has potential applications in advanced wastewater treatment for the removal of multiple pollutants from sewage.
Collapse
|
8
|
Hong P, Zhang K, Dai Y, Yuen CNT, Gao Y, Gu Y, Mei Yee Leung K. Application of aerobic denitrifier for simultaneous removal of nitrogen, zinc, and bisphenol A from wastewater. BIORESOURCE TECHNOLOGY 2022; 354:127192. [PMID: 35452828 DOI: 10.1016/j.biortech.2022.127192] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Revised: 04/16/2022] [Accepted: 04/16/2022] [Indexed: 06/14/2023]
Abstract
High concentrations of heavy metals and other pollutants affect microbial activity in the wastewater treatment system and impede biological denitrification process. In this study, a novel Zn(II)-resistant aerobic denitrifier (Pseudomonas stutzeri KY-37) was isolated with potential in Bisphenol A (BPA) biodegradation and removal. The capability of this denitrifier in removing nitrogen, zinc, and BPA was tested. Using 56 mg/L nitrate as the sole nitrogen source, its removal efficiency achieved 98.5% in 12 h. This novel denitrifier had a strong auto-aggregation (maximum 65.8%), a high hydrophobicity rate (maximum 88.2%), and a massive amount (maximum 41.1 mg/g cell dry weight) of extracellular polymeric substances (EPS) production. Moreover, Zn(II) removal efficiency reached more than 95% with the initial high concentrations of 200 mg/L. The maximum BPA removal efficiency reached 88.8% with initial 10 mg/L. The removal mechanism of BPA was further explored in terms of microbial degradation, EPS adsorption, and intermediate degradation products.
Collapse
Affiliation(s)
- Pei Hong
- Collaborative Innovation Center of Recovery and Reconstruction of Degraded Ecosystem in Wanjiang Basin Co-founded by Anhui Province and Ministry of Education, Provincial Key Laboratory of Biotic Environment and Ecological Safety in Anhui, School of Ecology and Environment, Anhui Normal University, Wuhu 241002, China; State Key Laboratory of Marine Pollution and Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong 999077, China
| | - Kai Zhang
- State Key Laboratory of Marine Pollution and Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong 999077, China; National Observation and Research Station of Coastal Ecological Environments in Macao, Macao Environmental Research Institute, Macau University of Science and Technology, Macao 999078, China
| | - Yue Dai
- Collaborative Innovation Center of Recovery and Reconstruction of Degraded Ecosystem in Wanjiang Basin Co-founded by Anhui Province and Ministry of Education, Provincial Key Laboratory of Biotic Environment and Ecological Safety in Anhui, School of Ecology and Environment, Anhui Normal University, Wuhu 241002, China
| | - Calista N T Yuen
- State Key Laboratory of Marine Pollution and Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong 999077, China
| | - Yuxin Gao
- Collaborative Innovation Center of Recovery and Reconstruction of Degraded Ecosystem in Wanjiang Basin Co-founded by Anhui Province and Ministry of Education, Provincial Key Laboratory of Biotic Environment and Ecological Safety in Anhui, School of Ecology and Environment, Anhui Normal University, Wuhu 241002, China
| | - Yali Gu
- Collaborative Innovation Center of Recovery and Reconstruction of Degraded Ecosystem in Wanjiang Basin Co-founded by Anhui Province and Ministry of Education, Provincial Key Laboratory of Biotic Environment and Ecological Safety in Anhui, School of Ecology and Environment, Anhui Normal University, Wuhu 241002, China
| | - Kenneth Mei Yee Leung
- State Key Laboratory of Marine Pollution and Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong 999077, China.
| |
Collapse
|
9
|
Extracellular Polymeric Substances and Biocorrosion/Biofouling: Recent Advances and Future Perspectives. Int J Mol Sci 2022; 23:ijms23105566. [PMID: 35628373 PMCID: PMC9143384 DOI: 10.3390/ijms23105566] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Revised: 05/10/2022] [Accepted: 05/13/2022] [Indexed: 11/17/2022] Open
Abstract
Microbial cells secrete extracellular polymeric substances (EPS) to adhere to material surfaces, if they get in contact with solid materials such as metals. After phase equilibrium, microorganisms can adhere firmly to the metal surfaces causing metal dissolution and corrosion. Attachment and adhesion of microorganisms via EPS increase the possibility and the rate of metal corrosion. Many components of EPS are electrochemical and redox active, making them closely related to metal corrosion. Functional groups in EPS have specific adsorption ability, causing them to play a key role in biocorrosion. This review emphasizes EPS properties related to metal corrosion and protection and the underlying microbially influenced corrosion (MIC) mechanisms. Future perspectives regarding a comprehensive study of MIC mechanisms and green methodologies for corrosion protection are provided.
Collapse
|
10
|
Cao Y, Xu Y, Li Q, Rose RS, Abrahams I, Jones CR, Sheriff TS. Corrosion Inhibition and Disinfection of Heating and Cooling Water Systems Using In Situ Generated Hydrogen Peroxide. NEW J CHEM 2022. [DOI: 10.1039/d2nj03806d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Aqueous solutions of MnCl2·4H2O and Tiron (disodium 4,5-dihydroxy-1,3-benzenedisulfonate) rapidly remove dioxygen (O2) from aqueous solution at a rate of ~20 mg∙ L -1 min-1 with turnover frequencies (TOFs) of up...
Collapse
|
11
|
Narenkumar J, Devanesan S, AlSalhi MS, Kokilaramani S, Ting YP, Rahman PK, Rajasekar A. Biofilm formation on copper and its control by inhibitor/biocide in cooling water environment. Saudi J Biol Sci 2021; 28:7588-7594. [PMID: 34867063 PMCID: PMC8626344 DOI: 10.1016/j.sjbs.2021.10.012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2021] [Revised: 09/27/2021] [Accepted: 10/04/2021] [Indexed: 11/29/2022] Open
Abstract
The present study has successfully identified the nitrate reducing bacteria present in the cooling water system and also investigated the performance of industrially applied biocide and inhibitor on the bacterial inhibition. In order to carry out the objective of this study, facilities and methods such as 16S rRNA gene sequencing, Lowry assay, SEM, EIS, ICP-MS and weight loss analysis were being utilized. In this study, two out of the five morphologically dis- similar colonies identified through 16S rRNA gene sequencing, namely the Massilia timonae and the Pseudomonas, were being utilized in the biocorrosion study on copper metal. From the surface analysis using SEM demonstrated the phenomenon of biofilm formation on the copper surface. 2-methylbenzimidazole has the addition of methyl group in the diazole ring position of benzimidazole it has create basicity environment and inhibit the metal deterioration. Meanwhile, it is also deducible from the EIS and protein analysis that com- bination of biocide with either of the inhibitors gives rise to better biocorrosion suppression (0.00178 mpy and 0.00171mpy) as compared to the sole effect of either biocide or inhibitor (0.00219 mpy, 0.00162 and 0.00143). Biocorrosion system biocide with MBM was found to exhibit 65% corrosion inhibition efficiency. Moreover, adoption of 2-Methylbenzimidazole seems to display better performance as compared to Multionic 8151, which is adopted in cooling water system.
Collapse
Affiliation(s)
- Jayaraman Narenkumar
- Centre for Materials Engineering and Regenerative Medicine, Bharath Institute of Higher Education and Research, Selaiyur, Chennai, Tamil Nadu 600073, India
| | - Sandhanasamy Devanesan
- Department of Physics and Astronomy, College of Science, Kingdom of Saudi Arabia, King Saud University, 11451 Riyadh, Saudi Arabia
| | - Mohamad S. AlSalhi
- Department of Physics and Astronomy, College of Science, Kingdom of Saudi Arabia, King Saud University, 11451 Riyadh, Saudi Arabia
| | - Seenivasan Kokilaramani
- Environmental Molecular Microbiology Research Laboratory, Department of Biotechnology, Thiruvalluvar University, Serkkadu, Vellore 632115, India
| | - Yen-Peng Ting
- Department of Chemical and Biomolecular Engineering, National University of Singapore, engineering Drive, Singapore 117576, Singapore
| | | | - Aruliah Rajasekar
- Environmental Molecular Microbiology Research Laboratory, Department of Biotechnology, Thiruvalluvar University, Serkkadu, Vellore 632115, India
- Corresponding author.
| |
Collapse
|
12
|
Hua P, Gao Q, Wang Z, Jiang S, de Oliveira KRF, Macedo DO. Modeling and elucidation the effects of iron deposits on chlorine decay and trihalomethane formation in drinking water distribution system. WATER RESEARCH 2021; 207:117804. [PMID: 34763282 DOI: 10.1016/j.watres.2021.117804] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Revised: 10/20/2021] [Accepted: 10/21/2021] [Indexed: 06/13/2023]
Abstract
Iron deposits stimulate chlorine consumption and trihalomethane (THM) formation in drinking water distribution systems through distinct mechanisms. In this study, a second-order chlorine decay model with a variable reaction-rate coefficient was developed to quantitatively evaluate the influences of iron deposits on chlorine reactions by considering the characteristics of dissolved organic matter (DOM), the type and dosages of deposits, as well as the initial chlorine concentrations. Based on a reliable prediction of residual chlorine, the concept that THM formation had a linear relationship with chlorine consumption was further validated by chlorination of DOM in the presence of iron deposits. Due to the catalysis influences, the reactivity of DOM towards chlorine decay or THM formation was accelerated. Although iron deposits activated the reactivity of DOM with bromine and chlorine, THM slightly shifted toward chlorinated species. Due to the adsorption influences, the maximum chlorine demand increased with the increasing deposit dosages whereas the extent of enhancement mainly relied on the DOM properties. Low-molecular-weight DOM with a hydrophilic characteristic was prone to be elevated by iron deposits. Based on the model simulation, approximately 20% of chlorine consumption and 37% of THM formation were contributed by deposits after 168 h reaction. The data provided herein emphasize the role of iron deposits in chlorine consumption and THM formation, which assist the water quality management in drinking water distribution systems.
Collapse
Affiliation(s)
- Pei Hua
- SCNU Environmental Research Institute, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety & MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, 510006 Guangzhou, China; School of Environment, South China Normal University, University Town, 510006 Guangzhou, China.
| | - Quan Gao
- SCNU Environmental Research Institute, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety & MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, 510006 Guangzhou, China; School of Environment, South China Normal University, University Town, 510006 Guangzhou, China
| | - Zhenyu Wang
- Institute of Urban and Industrial Water Management, Technische Universität Dresden, 01062 Dresden, Germany
| | - Shanshan Jiang
- SCNU Environmental Research Institute, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety & MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, 510006 Guangzhou, China; School of Environment, South China Normal University, University Town, 510006 Guangzhou, China
| | - Keila Roberta Ferreira de Oliveira
- Fundação Universidade Federal de Mato Grosso do Sul, Faculdade de Engenharias, Arquitetura e Urbanismo e Geografia, Av. Costa e Silva, s/no., Bairro Universitário, CEP: 79070-900 Campo Grande, MS, Brazil
| | - Dhiogo Okumoto Macedo
- Fundação Universidade Federal de Mato Grosso do Sul, Faculdade de Engenharias, Arquitetura e Urbanismo e Geografia, Av. Costa e Silva, s/no., Bairro Universitário, CEP: 79070-900 Campo Grande, MS, Brazil
| |
Collapse
|
13
|
Li C, Yu Y, Fang A, Feng D, Du M, Tang A, Chen S, Li A. Insight into biosorption of heavy metals by extracellular polymer substances and the improvement of the efficacy: a review. Lett Appl Microbiol 2021; 75:1064-1073. [PMID: 34562275 DOI: 10.1111/lam.13563] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 08/26/2021] [Accepted: 09/01/2021] [Indexed: 01/21/2023]
Abstract
Heavy metals are continuously released into aquatic environments in which they accumulate. This phenomenon endangers public health because heavy metals accumulate along the food chain. However, conventional remediation methods are inefficient, expensive and yield toxic intermediate products, which adversely affect the environment. The discovery of green bio-adsorbents such as microbial extracellular polymer substance (EPS) has quickly attracted considerable worldwide attention because of their low cost, high removal efficiency of heavy metals and industrial availability. Hence, this review considers the sources, hazards and treatment methods of heavy metals pollution, particularly the biosorption mechanism of EPS to heavy metals and the influencing factors of the bio-adsorption process, which are significant in the efficient removal of heavy metals-containing wastewater treatment. This review also focuses on strengthening the process of EPS adsorption of heavy metals, which can further contribute to heavy metals removal. Finally, it has been proposed that improving the yield, stability, selectivity and recoverability of EPS is the key direction of further research.
Collapse
Affiliation(s)
- C Li
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, People's Republic of China
| | - Y Yu
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, People's Republic of China
| | - A Fang
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, People's Republic of China
| | - D Feng
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, People's Republic of China
| | - M Du
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, People's Republic of China
| | - A Tang
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, People's Republic of China
| | - S Chen
- School of Municipal and Environmental Engineering, Jilin University of Architecture and Technology, Changchun, People's Republic of China
| | - A Li
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, People's Republic of China.,School of Municipal and Environmental Engineering, Jilin University of Architecture and Technology, Changchun, People's Republic of China
| |
Collapse
|
14
|
Shahini M, Ramezanzadeh B, Mohammadloo HE. Recent advances in biopolymers/carbohydrate polymers as effective corrosion inhibitive macro-molecules: A review study from experimental and theoretical views. J Mol Liq 2021. [DOI: 10.1016/j.molliq.2020.115110] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
|
15
|
Balakrishnan A, Jena G, Pongachira George R, Philip J. Polydimethylsiloxane-graphene oxide nanocomposite coatings with improved anti-corrosion and anti-biofouling properties. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:7404-7422. [PMID: 33033928 DOI: 10.1007/s11356-020-11068-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Accepted: 09/30/2020] [Indexed: 06/11/2023]
Abstract
We demonstrate enhanced anti-corrosion and anti-biofouling properties of graphene oxide-silica-polydimethylsiloxane (GSP) coating on carbon steel (CS). Electrochemical analyses of GSP-coated carbon steel exposed to Gram-positive Bacillus sp., Gram-negative Pseudomonas sp., and freshwater bacterial cultures for 72 h showed a 3-5 orders of magnitude reduction in icorr values and high impedance values (107 Ω) as compared with polished specimens. The corrosion protection efficiency of GSP-coated specimens was 99.9% against Bacillus sp. and freshwater culture and it was 89.6% against Pseudomonas sp. Evaluation of anti-biofouling property of GSP coating using microbiological and epifluorescence microscopic techniques showed three order reductions in total viable cells on GSP-coated specimens exposed to bacterial cultures. Confocal laser scanning microscopic analysis of biofilm architecture confirmed a significant reduction of biomass and biofilm thickness on GSP-coated CS demonstrating an excellent anti-biofouling activity of GSP.
Collapse
Affiliation(s)
- Anandkumar Balakrishnan
- Corrosion Science and Technology Division, Metallurgy and Materials Group, Indira Gandhi Centre for Atomic Research, Kalpakkam, 603102, India.
| | - Geetisubhra Jena
- Corrosion Science and Technology Division, Metallurgy and Materials Group, Indira Gandhi Centre for Atomic Research, Kalpakkam, 603102, India
- Homi Bhabha National Institute, Mumbai, 400094, India
| | - Rani Pongachira George
- Corrosion Science and Technology Division, Metallurgy and Materials Group, Indira Gandhi Centre for Atomic Research, Kalpakkam, 603102, India
| | - John Philip
- Corrosion Science and Technology Division, Metallurgy and Materials Group, Indira Gandhi Centre for Atomic Research, Kalpakkam, 603102, India
- Homi Bhabha National Institute, Mumbai, 400094, India
| |
Collapse
|
16
|
Bacillus subtilis extracellular polymeric substances conditioning layers inhibit Escherichia coli adhesion to silicon surfaces: A potential candidate for interfacial antifouling additives. Biointerphases 2021; 16:011003. [PMID: 33706527 DOI: 10.1116/6.0000737] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Biofouling on material surfaces is a ubiquitous problem in a variety of fields. In aqueous environments, the process of biofouling initiates with the formation of a layer of macromolecules called the conditioning layer on the solid-liquid interface, followed by the adhesion and colonization of planktonic bacteria and the subsequent biofilm development and maturation. In this study, the extracellular polymeric substances (EPS) secreted by Bacillus subtilis were collected and used to prepare conditioning layers on inert surfaces. The morphologies and antifouling performances of the EPS conditioning layers were investigated. It was found that the initial adhesion of Escherichia coli was inhibited on the surfaces precoated with EPS conditioning layers. To further explore the underlying antifouling mechanisms of the EPS conditioning layers, the respective roles of two constituents of B. subtilis EPS (γ-polyglutamic acid and surfactin) were investigated. This study has provided the possibility of developing a novel interfacial antifouling additive with the advantages of easy preparation, nontoxicity, and environmental friendliness.
Collapse
|
17
|
Ziadi I, El-Bassi L, Bousselmi L, Akrout H. Characterization of the biofilm grown on 304L stainless steel in urban wastewaters: extracellular polymeric substances (EPS) and bacterial consortia. BIOFOULING 2020; 36:977-989. [PMID: 33086880 DOI: 10.1080/08927014.2020.1836163] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Revised: 10/02/2020] [Accepted: 10/06/2020] [Indexed: 06/11/2023]
Abstract
Characterization of the biofilm growing on stainless steel (SS) in untreated (UTUWW) and treated (TUWW) urban wastewaters was performed. In both media, the first phase of biofilm growth was aerobic, when the genera Caldimonas, Caulobacter, Terriglobus and Edaphobacter (iron oxidizing bacteria [IOB]) and the genera Bacillus, Sulfurimonas, Syntrophobacter and Desulfobacter (sulfur oxidizing bacteria [SOB]) were identified. In the second phase, established after immersion for 7 days, the high amount of EPS inhibited the access of oxygen and promoted the growth of anaerobic bacteria, which were the genus Shewanella (iron-reducing bacterium [IRB]) and the genera Desulfovirga, Desulfovibrio, Desulfuromusa, Desulfococcus, and Desulfosarcina (sulfate-reducing bacteria [SRB]). Electrochemical measurements showed that in the first stage, the aerobic bacteria and the high amount of EPS delayed the cathodic reduction of oxygen. However, in the second stage, EPS and the anaerobic bacteria promoted anodic dissolution.
Collapse
Affiliation(s)
- Islem Ziadi
- Laboratory of Wastewaters and Environment, Centre of Water Researches and Technologies (CERTE), Soliman, Tunisia
- National Institute of Applied Sciences and Technology (INSAT), Carthage University, Tunis, Tunisia
| | - Leila El-Bassi
- Laboratory of Wastewaters and Environment, Centre of Water Researches and Technologies (CERTE), Soliman, Tunisia
| | - Latifa Bousselmi
- Laboratory of Wastewaters and Environment, Centre of Water Researches and Technologies (CERTE), Soliman, Tunisia
| | - Hanene Akrout
- Laboratory of Wastewaters and Environment, Centre of Water Researches and Technologies (CERTE), Soliman, Tunisia
| |
Collapse
|
18
|
Li LY, Han ZZ, Zeng RC, Qi WC, Zhai XF, Yang Y, Lou YT, Gu T, Xu D, Duan JZ. Microbial ingress and in vitro degradation enhanced by glucose on bioabsorbable Mg-Li-Ca alloy. Bioact Mater 2020; 5:902-916. [PMID: 32637753 PMCID: PMC7329939 DOI: 10.1016/j.bioactmat.2020.06.014] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 06/07/2020] [Accepted: 06/08/2020] [Indexed: 01/10/2023] Open
Abstract
Biodegradable magnesium alloys are challenging to be implanted in patients with hyperglycemia and diabetes. A hypothesis is suggested that glucose accelerates microbial ingress and in vitro degradation of Mg-Li-Ca implants. Corrosion resistance and mechanical properties was demonstrated using electrochemical, hydrogen evolution and tensile tests. The bacteria from Hank's solution were isolated via 16S rRNA gene analysis. The results revealed that Mg-1Li-1Ca alloy exhibited different responses to Hank's solution with and without glucose. The solution acidity was ascribed to Microbacterium hominis and Enterobacter xiangfangensis, indicating that glucose promoted microbial activity and degradation and deterioration in mechanical property of Mg-1Li-1Ca alloy.
Collapse
Affiliation(s)
- Ling-Yu Li
- Corrosion Laboratory for Light Metals, College of Material Science and Engineering, Shandong University of Science and Technology, Qingdao, 266590, China
| | - Zhuang-Zhuang Han
- Corrosion Laboratory for Light Metals, College of Material Science and Engineering, Shandong University of Science and Technology, Qingdao, 266590, China
| | - Rong-Chang Zeng
- Corrosion Laboratory for Light Metals, College of Material Science and Engineering, Shandong University of Science and Technology, Qingdao, 266590, China.,School of Materials Science and Engineering, Zhengzhou University, Zhengzhou, 450002, China
| | - Wei-Chen Qi
- Corrosion Laboratory for Light Metals, College of Material Science and Engineering, Shandong University of Science and Technology, Qingdao, 266590, China
| | - Xiao-Fan Zhai
- Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266590, China
| | - Yi Yang
- Shenyang National Laboratory for Materials Science, Northeastern University, Shenyang, 110819, China
| | - Yun-Tian Lou
- Shenyang National Laboratory for Materials Science, Northeastern University, Shenyang, 110819, China
| | - Tingyue Gu
- Department of Chemical & Biomolecular Engineering, Russ College of Engineering and Technology, Ohio University, Athens, OH, 45701-2979, USA
| | - Dake Xu
- Shenyang National Laboratory for Materials Science, Northeastern University, Shenyang, 110819, China
| | - Ji-Zhou Duan
- Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266590, China
| |
Collapse
|
19
|
Anandkumar B, George RP, Philip J. Efficacy of imidazolium and piperidinium based ionic liquids on inhibiting biofilm formation on titanium and carbon steel surfaces. Anal Chim Acta 2020; 1126:38-51. [PMID: 32736723 DOI: 10.1016/j.aca.2020.05.072] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Accepted: 05/29/2020] [Indexed: 12/11/2022]
Abstract
In the present study, the efficacies of three different cationic and anionic ionic liquids (ILs) on biofilm formation on materials used in cooling water systems were evaluated. Two imidazolium based ILs; 1-Ethyl 3-Methylimidazolium tetrafluoroborate - (IL-E) and 1-Butyl-3-methylimidazolium chloride - (IL-I) with anionic fluoride and chloride groups and one piperidinium based IL, N-methyl-N-propylpiperidinium bis(trifluoromethylsulfonyl)imide - (IL-M) with fluoromethyl group as anion were used. The efficacy of these ILs were evaluated on planktonic and sessile cells of major biofilm formers in cooling water systems using Gram negative bacterium Pseudomonas sp. and Gram positive bacterium Bacillus sp. Further their effect on inhibiting biofilm formation on titanium and carbon steel surfaces were also evaluated. Results showed that planktonic cells of Pseudomonas sp. and Bacillus sp. were effectively inhibited by 25 ppm of IL-M and IL-E, respectively. For both bacteria, 50 ppm of IL-I was enough to inhibit and eradicate the sessile cell formation. Among the three ILs, IL-E was the best in inhibiting the adhesion of bacterial cells on Ti and CS surfaces. These results suggest that Imidazolium based ILs are effective in controlling sessile cell formation and eradicating mature biofilm as compared to piperidinium based IL. Further, Imidazolium based IL with fluoride anion (IL-E) was the best in inhibiting adhesion of these bacterial cells and thereby biofilm formation on material surfaces. This study establishes the feasibility of using ILs in cooling water system for bacterial biofilm control along with other conventional biofouling control methods.
Collapse
Affiliation(s)
- B Anandkumar
- Corrosion Science and Technology Division, Metallurgy and Materials Group Indira Gandhi Centre for Atomic Research, Kalpakkam, 603102, India.
| | - R P George
- Corrosion Science and Technology Division, Metallurgy and Materials Group Indira Gandhi Centre for Atomic Research, Kalpakkam, 603102, India
| | - John Philip
- Corrosion Science and Technology Division, Metallurgy and Materials Group Indira Gandhi Centre for Atomic Research, Kalpakkam, 603102, India; Homi Bhabha National Institute, Kalpakkam, 603102, India
| |
Collapse
|
20
|
Narenkumar J, AlSalhi MS, Arul Prakash A, Abilaji S, Devanesan S, Rajasekar A, Alfuraydi AA. Impact and Role of Bacterial Communities on Biocorrosion of Metals Used in the Processing Industry. ACS OMEGA 2019; 4:21353-21360. [PMID: 31867530 PMCID: PMC6921611 DOI: 10.1021/acsomega.9b02954] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Accepted: 11/15/2019] [Indexed: 05/04/2023]
Abstract
In the present study, the effects of the corrosive bacterial community and the biofilm on cooling water systems made from mild steel (MS) and brass (BR) were studied under field exposure conditions using electrochemical impedance spectroscopy measurements, scanning electron microscope, and X-ray diffraction methods. Results from16S rRNA gene sequences showed that the predominant bacteria species detected in the biofilm of MS and BR metals during 360 days of exposure were Bacillus cereus EN14, Achromobacter xylosoxidans EN15, A. xylosoxidans EN16, and B. cereus EN17. The weight loss results revealed that a higher corrosion rate was observed in MS (0.7 ± 0.1 mm/y) compared with that in BR (0.17 ± 0.05 mm/y) at the end of the exposure period. This can be explained by the bacterial communities enhancing the corrosion rates by creating a local corrosive environment. Scanning electron microscope images revealed the adsorption of biofilm on the MS and BR surfaces following180 days of exposure. From the electrochemical impedance study, a higher charge transfer resistance (R ct) was obtained for BR (119.6 Ω cm2) when compared with that of MS (43.4 Ω cm2). This study explains the role of bacterial communities and their mechanisms in the corrosion of MS and BR in cooling water systems.
Collapse
Affiliation(s)
- Jayaraman Narenkumar
- Environmental Molecular Microbiology
Research
Laboratory, Department of Biotechnology, Thiruvalluvar University, Serkkadu, Vellore 632115, Tamilnadu, India
- Shenyang
National Laboratory for Materials Science, Northeastern University, Shenyang 110819, China
| | - Mohamad S. AlSalhi
- Department
of Physics and Astronomy, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia
- E-mail: , (M.S.A.)
| | - Arumugam Arul Prakash
- Environmental Molecular Microbiology
Research
Laboratory, Department of Biotechnology, Thiruvalluvar University, Serkkadu, Vellore 632115, Tamilnadu, India
| | - Subramani Abilaji
- Environmental Molecular Microbiology
Research
Laboratory, Department of Biotechnology, Thiruvalluvar University, Serkkadu, Vellore 632115, Tamilnadu, India
| | - Sandhanasamy Devanesan
- Department
of Physics and Astronomy, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia
| | - Aruliah Rajasekar
- Environmental Molecular Microbiology
Research
Laboratory, Department of Biotechnology, Thiruvalluvar University, Serkkadu, Vellore 632115, Tamilnadu, India
- E-mail: , (A.R.)
| | - Akram A. Alfuraydi
- Department
of Botany and Microbiology, College of Science, King Saud University, Riyadh 11451, Saudi Arabia
| |
Collapse
|
21
|
Ziadi I, Alves MM, Taryba M, El-Bassi L, Hassairi H, Bousselmi L, Montemor MF, Akrout H. Microbiologically influenced corrosion mechanism of 304L stainless steel in treated urban wastewater and protective effect of silane-TiO 2 coating. Bioelectrochemistry 2019; 132:107413. [PMID: 31816578 DOI: 10.1016/j.bioelechem.2019.107413] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Revised: 11/08/2019] [Accepted: 11/08/2019] [Indexed: 12/14/2022]
Abstract
Microbiologically influenced corrosion (MIC) of bare and silane-TiO2 sol-gel coated stainless steel (SS) was studied in treated urban wastewater (TUWW). Combining the electrochemical impedance spectroscopy (EIS) and the scanning vibrating electrode technique (SVET) showed that SS surface colonization occurs, at earlier stages, by iron-oxidizing bacteria (IOB), and later by sulphate-reducing bacteria (SRB). The SVET results showed that chemical corrosion process and bacterial respiration led to the depletion of dissolved oxygen, creating a differential aeration cell and thus a localized corrosion phenomenon. Scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) showed that the growth of a bacterial biofilm on 304L SS was a dynamic process, stimulating the localized oxidation of SS. To improve corrosion protection, a silane-TiO2 sol-gel coating for SS is proposed. SEM showed that the coating reduced bacterial adhesion and EIS study demonstrated that the coating improved the barrier properties and corrosion resistance of 304L SS in TUWW over a short period of immersion.
Collapse
Affiliation(s)
- I Ziadi
- Laboratory for Wastewaters and Environment, Centre of Water Researches and Technologies (CERTE) Technopark of Borj Cedria PB 273, Soliman 8020, Tunisia; National Institute of Applied Science and Technology (INSAT), Carthage University, Tunis, Tunisia
| | - M M Alves
- CQE, Departamento de Engenharia Química, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, Lisboa 1049-001, Portugal
| | - M Taryba
- CQE, Departamento de Engenharia Química, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, Lisboa 1049-001, Portugal
| | - L El-Bassi
- Laboratory for Wastewaters and Environment, Centre of Water Researches and Technologies (CERTE) Technopark of Borj Cedria PB 273, Soliman 8020, Tunisia
| | - H Hassairi
- Laboratory for Wastewaters and Environment, Centre of Water Researches and Technologies (CERTE) Technopark of Borj Cedria PB 273, Soliman 8020, Tunisia
| | - L Bousselmi
- Laboratory for Wastewaters and Environment, Centre of Water Researches and Technologies (CERTE) Technopark of Borj Cedria PB 273, Soliman 8020, Tunisia
| | - M F Montemor
- CQE, Departamento de Engenharia Química, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, Lisboa 1049-001, Portugal
| | - H Akrout
- Laboratory for Wastewaters and Environment, Centre of Water Researches and Technologies (CERTE) Technopark of Borj Cedria PB 273, Soliman 8020, Tunisia. @gmail.com
| |
Collapse
|
22
|
Song P, Zhou B, Feng G, Brooks JP, Zhou H, Zhao Z, Liu Y, Li Y. The influence of chlorination timing and concentration on microbial communities in labyrinth channels: implications for biofilm removal. BIOFOULING 2019; 35:401-415. [PMID: 31142151 DOI: 10.1080/08927014.2019.1600191] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Revised: 03/18/2019] [Accepted: 03/22/2019] [Indexed: 06/09/2023]
Abstract
Chlorination is an effective method to control biofilm formation in enclosed pipelines. To date, very little is known about how to control biofilms at the mesoscale in complex pipelines through chlorination. In this study, the dynamic of microbial communities was examined under different residual chlorine concentrations on the biofilms attached to labyrinth channels for drip irrigation using reclaimed water. The results indicated that the microbial phospholipid fatty acids, extracellular polymeric substances, microbial dynamics, and the ace and Shannon microbial diversity indices showed a gradual decrease after chlorination. However, chlorination increased microbial activity by 0.5-19.2%. The increase in the relative abundances of chloride-resistant bacteria (Acinetobacter and Thermomonas) could lead to a potential risk of chlorine resistance. Thus, keeping a low chlorine concentration (0.83 mg l-1 for 3 h) is effective for controlling biofilm formation in the labyrinth channels.
Collapse
Affiliation(s)
- Peng Song
- a College of Water Resources and Civil Engineering , China Agricultural University , Beijing , PR China
- b Genetics and Sustainable Agricultural Research Unit , United States Department of Agriculture , Starkville , MS , USA
| | - Bo Zhou
- a College of Water Resources and Civil Engineering , China Agricultural University , Beijing , PR China
- c College of Agricultural and Life Sciences , University of Wisconsin-Madison , Madison , WI , USA
| | - Gary Feng
- b Genetics and Sustainable Agricultural Research Unit , United States Department of Agriculture , Starkville , MS , USA
| | - John P Brooks
- b Genetics and Sustainable Agricultural Research Unit , United States Department of Agriculture , Starkville , MS , USA
| | - Hongxu Zhou
- a College of Water Resources and Civil Engineering , China Agricultural University , Beijing , PR China
| | - Zhirui Zhao
- d Research Center for Eco-environmental Sciences , Chinese Academy of Sciences , Beijing , PR China
| | - Yaoze Liu
- e Department of Environmental and Sustainable Engineering , University at Albany , Albany , NY , USA
| | - Yunkai Li
- a College of Water Resources and Civil Engineering , China Agricultural University , Beijing , PR China
| |
Collapse
|
23
|
Gao Y, Trueman BF, Stoddart AK, Gagnon GA. Understanding the Impact of Extracellular Polymeric Substances on Lead Release in Drinking Water Systems. ACS OMEGA 2018; 3:14824-14832. [PMID: 30555991 PMCID: PMC6289567 DOI: 10.1021/acsomega.8b02363] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Accepted: 10/26/2018] [Indexed: 05/16/2023]
Abstract
Lead release in a lead (Pb, anode)-iron oxide (α-Fe2O3, cathode) galvanic system was studied under the influence of synthetic extracellular polymeric substances (sEPS). Sodium alginate, bovine serum albumin (BSA), and cytochrome c represented extracellular polysaccharides, proteins, and electrochemically active components, respectively. Microbiologically influenced corrosion was investigated using sEPS and pelleted and resuspended Pseudomonas aeruginosa cells. Relative to the anaerobic inorganic control, Pb release increased by 156, 202, and 198 μg/L when sEPS was present on the cathode side at 200 mg/L (100 mg/L alginate + 100 mg/L BSA), 400 mg/L (200 mg/L alginate + 200 mg/L BSA), and 200 mg/L with 123.84 mg/L cytochrome c, respectively, under anaerobic conditions. When the cathode was aerated, Pb release increased by 75, 260, and -71 μg/L under the aforementioned conditions, all relative to the aerated inorganic control. When sEPS was instead present on the anode side, sEPS caused localized corrosion on Pb and resulted in higher Pb release than predicted by electric current. P. aeruginosa generally enhanced corrosion; when cells were dosed in the anode side, part of the oxidized Pb was immobilized by cells or organic compounds adhered to the electrodes.
Collapse
|
24
|
Shen Y, Huang PC, Huang C, Sun P, Monroy GL, Wu W, Lin J, Espinosa-Marzal RM, Boppart SA, Liu WT, Nguyen TH. Effect of divalent ions and a polyphosphate on composition, structure, and stiffness of simulated drinking water biofilms. NPJ Biofilms Microbiomes 2018; 4:15. [PMID: 30038792 PMCID: PMC6052100 DOI: 10.1038/s41522-018-0058-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2017] [Revised: 05/24/2018] [Accepted: 06/01/2018] [Indexed: 02/04/2023] Open
Abstract
The biofilm chemical and physical properties in engineered systems play an important role in governing pathogen transmission, fouling facilities, and corroding metal surfaces. Here, we investigated how simulated drinking water biofilm chemical composition, structure, and stiffness responded to the common scale control practice of adjusting divalent ions and adding polyphosphate. Magnetomotive optical coherence elastography (MM-OCE), a tool developed for diagnosing diseased tissues, was used to determine biofilm stiffness in this study. MM-OCE, together with atomic force microscopy (AFM), revealed that the biofilms developed from a drinking water source with high divalent ions were stiffer compared to biofilms developed either from the drinking water source with low divalent ions or the water containing a scale inhibitor (a polyphosphate). The higher stiffness of biofilms developed from the water containing high divalent ions was attributed to the high content of calcium carbonate, suggested by biofilm composition examination. In addition, by examining the biofilm structure using optical coherence tomography (OCT), the highest biofilm thickness was found for biofilms developed from the water containing the polyphosphate. Compared to the stiff biofilms developed from the water containing high divalent ions, the soft and thick biofilms developed from the water containing polyphosphate will be expected to have higher detachment under drinking water flow. This study suggested that water chemistry could be used to predict the biofilm properties and subsequently design the microbial safety control strategies. A variety of analytical techniques are revealing the complex influences of ions in drinking water supplies on the structure of biofilms. Such biofilms often contaminate water supply pipes and machinery. Yun Shen and colleagues at the University of Illinois at Urbana-Champaign in the USA investigated the effects of ions with a double positive charge – ‘divalent cations’ – and polyphosphate ions. Divalent cations, especially calcium and magnesium ions, are abundant in drinking water in many regions, promoting the formation of limescale deposits. Polyphosphates are commonly added to water supplies to reduce limescale formation, inhibit corrosion and discourage biofilm formation. The research revealed that divalent cations increase biofilm stiffness, while polyphosphates promote softer but thicker biofilms that are more easily removed. The results will help optimize water treatment procedures to control both microbial contamination and limescale problems.
Collapse
Affiliation(s)
- Yun Shen
- 1Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, Urbana, IL USA.,4Present Address: University of Michigan, 1351 Beal Ave., 219 EWRE Bldg, Ann Arbor, MI 48109-2125 USA
| | - Pin Chieh Huang
- 2Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, IL USA
| | - Conghui Huang
- 1Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, Urbana, IL USA
| | - Peng Sun
- 1Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, Urbana, IL USA
| | - Guillermo L Monroy
- 2Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, IL USA
| | - Wenjing Wu
- 1Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, Urbana, IL USA
| | - Jie Lin
- 1Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, Urbana, IL USA
| | - Rosa M Espinosa-Marzal
- 1Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, Urbana, IL USA
| | - Stephen A Boppart
- 2Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, IL USA.,3Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, IL USA
| | - Wen-Tso Liu
- 1Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, Urbana, IL USA
| | - Thanh H Nguyen
- 1Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, Urbana, IL USA
| |
Collapse
|
25
|
Baig SA, Lou Z, Baig MA, Qasim M, Shams DF, Mahmood Q, Xu X. Assessment of tap water quality and corrosion scales from the selected distribution systems in northern Pakistan. ENVIRONMENTAL MONITORING AND ASSESSMENT 2017; 189:194. [PMID: 28357720 DOI: 10.1007/s10661-017-5907-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2016] [Accepted: 03/21/2017] [Indexed: 06/06/2023]
Abstract
Corrosion deposits formed within drinking water distribution systems deteriorate drinking water quality and resultantly cause public health consequences. In the present study, an attempt was made to investigate the concurrent conditions of corrosion scales and the drinking water quality in selected water supply schemes (WSS) in districts Chitral, Peshawar, and Abbottabad, northern Pakistan. Characterization analyses of the corrosion by-products revealed the presence of α-FeOOH, γ-FeOOH, Fe3O4, and SiO2 as major constituents with different proportions. The constituents of all the representative XRD peaks of Peshawar WSS were found insignificant as compared to other WSS, and the reason could be the variation of source water quality. Well-crystallized particles in SEM images indicated the formation of dense oxide layer on corrosion by-products. A wider asymmetric vibration peak of SiO2 appeared only in Chitral and Abbottabad WSS, which demonstrated higher siltation in the water source. One-way ANOVA analysis showed significant variations in pH, turbidity, TDS, K, Mg, PO4, Cl, and SO4 values, which revealed that these parameters differently contributed to the source water quality. Findings from this study suggested the implementation of proper corrosion prevention measures and the establishment of international collaboration for best corrosion practices, expertise, and developing standards.
Collapse
Affiliation(s)
- Shams Ali Baig
- Department of Environmental Sciences, Abdul Wali Khan University, Mardan, 23200, Pakistan.
- Department of Environmental Sciences, COMSATS Institute of Information Technology (CIIT), Abbottabad, 22060, Pakistan.
| | - Zimo Lou
- Department of Environmental Engineering, Zhejiang University, Hangzhou, 310058, People's Republic of China
| | - Muzaffar Ali Baig
- Department of Statistics, University of Peshawar, Peshawar, 25120, Pakistan
| | - Muhammad Qasim
- Department of Environmental Sciences, Abdul Wali Khan University, Mardan, 23200, Pakistan
| | - Dilawar Farhan Shams
- Department of Environmental Sciences, Abdul Wali Khan University, Mardan, 23200, Pakistan
| | - Qaisar Mahmood
- Department of Environmental Sciences, COMSATS Institute of Information Technology (CIIT), Abbottabad, 22060, Pakistan
| | - Xinhua Xu
- Department of Environmental Engineering, Zhejiang University, Hangzhou, 310058, People's Republic of China
| |
Collapse
|
26
|
Dec W, Mosiałek M, Socha RP, Jaworska-Kik M, Simka W, Michalska J. The effect of sulphate-reducing bacteria biofilm on passivity and development of pitting on 2205 duplex stainless steel. Electrochim Acta 2016. [DOI: 10.1016/j.electacta.2016.07.043] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
|
27
|
Jin J, Wu G, Guan Y. Effect of bacterial communities on the formation of cast iron corrosion tubercles in reclaimed water. WATER RESEARCH 2015; 71:207-18. [PMID: 25618521 DOI: 10.1016/j.watres.2014.12.056] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2014] [Revised: 11/26/2014] [Accepted: 12/15/2014] [Indexed: 05/28/2023]
Abstract
To understand the role bacterial communities play in corrosion scale development, the morphological and physicochemical characteristics of corrosion scales in raw and disinfected reclaimed water were systematically investigated. Corrosion tubercles were found in raw reclaimed water while thin corrosion layers formed in disinfected reclaimed water. The corrosion tubercles, composed mainly of α-FeOOH, γ-FeOOH, and CaCO3, consisted of an top surface; a shell containing more magnetite than other layers; a core in association with stalks produced by bacteria; and a corroded layer. The thin corrosion layers also had layered structures. These had a smooth top, a dense middle, and a corroded layer. They mostly consisted of the same main components as the tubercles in raw reclaimed water, but with different proportions. The profiles of the dissolved oxygen (DO) concentration, redox potential, and pH in the tubercles were different to those in the corrosion layers, which demonstrated that these parameters changed with a shift in the microbial processes in the tubercles. The bacterial communities in the tubercles were found to be dominated by Proteobacteria (56.7%), Bacteroidetes (10.0%), and Nitrospira (6.9%). The abundance of sequences affiliated to iron-reducing bacteria (IRB, mainly Geothrix) and iron-oxidizing bacteria (mainly Aquabacterium) was relatively high. The layered characteristics of the corrosion layers was due to the blocking of DO transfer by the development of the scales themselves. Bacterial communities could at least promote the layering process and formation of corrosion tubercles. Possible mechanisms might include: (1) bacterial communities mediated the pH and redox potential in the tubercles (which helped to form shell-like and core layers), (2) the metabolism of IRB and magnetic bacteria (Magnetospirillum) might contribute to the presence of Fe3O4 in the shell-like layer, while IRB contributed to green rust in the core layer, and (3) the diversity of the bacterial community resulted in the complex composition of the core layer, and gas producing bacteria (sulfate-reducing bacteria and methanogenic bacteria) played a role in the formation of the porous core layer.
Collapse
Affiliation(s)
- Juntao Jin
- Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, China; School of Environment, Tsinghua University, Beijing 100084, China
| | - Guangxue Wu
- Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, China; State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (MARC), Tsinghua University, Shenzhen 518055, Guangdong, China
| | - Yuntao Guan
- Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, China; State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (MARC), Tsinghua University, Shenzhen 518055, Guangdong, China.
| |
Collapse
|
28
|
Jin J, Guan Y. The mutual co-regulation of extracellular polymeric substances and iron ions in biocorrosion of cast iron pipes. BIORESOURCE TECHNOLOGY 2014; 169:387-394. [PMID: 25069092 DOI: 10.1016/j.biortech.2014.06.059] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2014] [Revised: 06/16/2014] [Accepted: 06/18/2014] [Indexed: 06/03/2023]
Abstract
New insights into the biocorrosion process may be gained through understanding of the interaction between extracellular polymeric substances (EPS) and iron. Herein, the effect of iron ions on the formation of biofilms and production of EPS was investigated. Additionally, the impact of EPS on the corrosion of cast iron coupons was explored. The results showed that a moderate concentration of iron ions (0.06 mg/L) promoted both biofilm formation and EPS production. The presence of EPS accelerated corrosion during the initial stage, while inhibited corrosion at the later stage. The functional groups of EPS acted as electron shuttles to enable the binding of iron ions. Binding of iron ions with EPS led to anodic dissolution and promoted corrosion, while corrosion was later inhibited through oxygen reduction and availability of phosphorus from EPS. The presence of EPS also led to changes in crystalline phases of corrosion products.
Collapse
Affiliation(s)
- Juntao Jin
- Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, Guangdong, China; School of Environment, Tsinghua University, Beijing 100084, China
| | - Yuntao Guan
- Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, Guangdong, China; State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (MARC), Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, Guangdong, China.
| |
Collapse
|