月桂酸和硫脲在饱和CO_2和SRB共存污水中缓蚀行为的研究  

Corrosion Inhibition Performance of Lauric Acid and Thiourea for Carbon Steel in a CO_2-saturated and SRB-containing Artificial Sewage

作　　者：吴亚楠[1] 张帆[1] 刘宏伟[1] 刘宏芳[1] 

机构地区：[1]华中科技大学化学与化工学院材料与环境化学研究所,武汉430074

出　　处：《腐蚀科学与防护技术》2015年第3期219-225,共7页Corrosion Science and Protection Technology

基　　金：国家自然科学基金项目(51171067);深圳市基础研发基金项目(JC201005310696A)资助

摘　　要：通过电化学方法、腐蚀失重法、超景深三维立体显微镜和菌量测定等方法,研究了常用缓蚀剂(月桂酸、硫脲)在含有硫酸盐还原菌(SRB)的饱和CO2产出水中的缓蚀行为。结果表明:在无菌饱和CO2介质中,月桂酸、硫脲对碳钢的最大缓蚀率分别为:98.6%和94.6%,且二者均是主要控制阴极抑制型缓蚀剂。在含SRB饱和CO2介质中,月桂酸和硫脲的缓蚀性能下降,缓蚀率分别只有62.9%和53.5%,且碳钢试片表面出现大量腐蚀坑。菌量测定结果表明,月桂酸和硫脲能够促进SRB生长,且SRB代谢产物阻碍月桂酸和硫脲在碳钢金属表面吸附,因此,这两种缓蚀剂均不适用于含有SRB的工况环境中。Corrosion inhibition performance of common inhibitors such as lauric acid and thioure for carbon steel in a CO2-saturated and SRB-containing artificial sewage was studied by means of electrochemical methods, mass loss method, three-dimensional stereoscopic microscope and quantitative measurement of the bacteria amount. The results show that in a sterilized and CO2-saturated medium, the inhibition efficiencies of lauric acid and thiourea were 98.6%, 94.6% respectively; the two inhibitors lauric acid and thiourea were all mix- type inhibitors which mainly suppress the cathodic process. In the SRB-containing and CO2-saturated medium, lauric acid and thiourea exhibit low inhibition efficiency: 62.9% and 53.5%, respectively, while there exist a lot of corrosion pits on the steel surface; and the inhibitors lauric acid and thiourea can promote the growth of SRB, while the metabolites of SRB prevent the adsorption of lauric acid and thiourea on the metal surface.Therefore, the two inhibitors may not be suitable to apply in those SRB-containing environments.

关 键 词：CO2腐蚀 微生物 缓蚀剂 20#碳钢 

分 类 号：TG174.42[金属学及工艺—金属表面处理]