海洋微生物腐蚀的电化学研究方法

ELECTROCHEMICAL METHODS FOR STUDY OF MICROBIOLOGICALLY INFLUENCED CORROSION IN MARINE ENVIRONMENT

海洋微生物引起的腐蚀对海洋结构物造成了日益严重的危害,其特征是微生物附着于金属表面并形成聚合物膜——生物膜,该生物膜改变了膜内的环境条件(如溶解氧、pH值、各种离子含量等),并伴有微生物对电化学反应的催化过程,因此加速了金属的腐蚀.本文介绍了监测腐蚀电位、氧化还原电位、极化电阻、强极化技术、电化学阻抗谱、电化学噪声、电化学表面成象、双区电池等方法在微生物腐蚀研究中的应用,指出了这些方法的使用条件和优缺点.为了保持微生物本身的活性,非破坏性的原位测量方法是重要的发展方向.

Microbiologically influenced corrosion (MIC) is a serious problem for marine engineering structures. MIC is characterized by that microorganisms attach to the surfaces of metal or alloy, and form biofilms which change corrosive conditions such as dissolved oxygen, pH and chemical species contents within the biofilm, then accelerate corrosion. Various electrochemical methods for MIC study are reviewed, including corrosion potential, redox potential, potential, polarization resistance, polarization curve, eletrochemical impedance spectrocopy (EIS), electrochemical noise analysis (ENA), electrochemical surface imaging and dual cell techniques. Their advantages and disadvantages are compared. It is pointed out that non-destructive in situ measurements (EIS, ENA) will be the main techniques in oredr to keep activity of microorganisms.