十二烷基二甲基苄基氯化铵与KI对钢在柠檬酸中的缓蚀协同效应  

Synergistic inhibition effect of dodecyl dimethyl benzyl ammonium chloride and potassium iodide on steel in citric acid

作　　者：王浩权 雷然[1,2] 李向红 WANG Hao-quan;LEI Ran;LI Xiang-hong(Key Laboratory of State Forestry and Grassland Administration on Highly-Efficient Utilization of Forestry Biomass Resources in Southwest China,Southwest Forestry University,Kunming 650224,China;College of Chemical Engineering,Southwest Forestry University,Kunming 650224,China)

机构地区：[1]西南林业大学西南地区林业生物质资源高效利用国家林业和草原局重点实验室,云南昆明650224 [2]西南林业大学化学工程学院,云南昆明650224

出　　处：《化学研究与应用》2022年第8期1778-1790,共13页Chemical Research and Application

基　　金：云南省基础研究计划杰出青年项目(202001AV070008)资助;国家自然科学基金项目(52161016)资助;云南省万人计划“青年拔尖人才”专项(51900109)资助。

摘　　要：采用静态失重法、动电位极化曲线、电化学阻抗谱(EIS)、扫描电子显微镜(SEM)首次研究了阳离子表面活性剂十二烷基二甲基苄基氯化铵(1227)对冷轧钢在1.0 mol/L柠檬酸(H_(3)C_(6)H_(5)O_(7))溶液中的缓蚀性能,并研究其与碘化钾(KI)复配后缓蚀协同效应和作用机制。结果表明:单独1227或KI均能一定程度抑制冷轧钢在柠檬酸中的腐蚀,100 mg/L 1227与200 mg/L KI复配后最大缓蚀率高达95.3%。缓蚀协同效应系数(s)高于1,表明两者复配后存在协同效应。1227、KI及1227/KI的吸附行为均符合Langmuir吸附等温方程式。1227与KI协同后的吸附平衡常数进一步增大,标准吸附Gibbs自由能(ΔG^(Ө))降低;极化曲线表明1227、KI、1227/KI同时对阴阳两极反应产生抑制作用,为“几何覆盖”模型的混合抑制型缓蚀剂。Nyquist图呈两个时间常数的高频区弥散容抗弧和低频区的小感抗弧,1227与KI复配后的电荷转移电阻进一步增大,缓蚀性能进一步增强;SEM微观形貌表明1227/KI复配缓蚀剂能更有效抑制柠檬酸介质对钢表面的腐蚀,表明二者协同作用后具有良好的缓蚀效果。The synergistic inhibition and mechanism of the cationic surfactant of dodecyl dimethyl benzyl ammonium chloride(1227)with potassium iodide(KI)on cold rolled steel(CRS)in 1.0 mol/L citric acid(H_(3)C_(6)H_(5)O_(7))solution was firstly studied by static weight loss measurements,potentiodynamic polarization curves,electrochemical impedance spectroscopy(EIS)and scanning electron microscope(SEM).The experimental results show that individual 1227 or KI can retard the corrosion of steel in citric acid media to some extent.When 1227 is mixed with KI,the inhibition performance is significantly improved.When 100 mg/L 1227 is combined with 200 mg/L KI,the maximum inhibition efficiency can reach as high as 95.3%.The synergistic inhibition parameters(s)are higher than 1,indicating that there is a synergism between 1227 and KI.The adsorption of the independent 1227,KI and 1227/KI mixtures all fit the Langmuir adsorption isotherm.The adsorption equilibrium constant turns to become higher after com-bing 1227 with KI,while the standard adsorption Gibbs free energy(ΔG^(Ө))becomes more negative.Polarization curves show that 1227,KI,and 1227/KI simultaneously inhibit the cathodic and anodic reactions,and can be arranged as mixed inhibitors with the mechanism of"geometric blocking coverage".Nyquist diagram shows two time constants for the high frequency region of the diffuse capacitive reactance arc and the low frequency region for the small inductive reactance arc,the charge transfer resistance further in-creases for the mixture of 1227 and KI,and then the inhibition performance is more improved.SEM micrographs clearly indicate that the combination of 1227 with KI can effectively inhibit CRS corrosion by citric acid solution,thus the synergistic action helps to im-prove the inhibitive action.

关 键 词：缓蚀 协同效应 柠檬酸 十二烷基二甲基苄基氯化铵 碘化钾 

分 类 号：O614.7[理学—无机化学]