核桃青皮提取物复配缓蚀剂对柠檬酸溶液中钢的协同效应  

Synergistic Effect of Walnut Green Husk Extract Complex Inhibitors on Steel in Citric Acid

作　　者：李向红[1,2] 邓书端 雷然 吴浩[1,2] Li Xianghong;Deng Shuduan;Lei Ran;Wu Hao(Key Laboratory of National Forestry and Grassland Administration on Highly-Efficient Utilization of Forestry Biomass Resources in Southwest China,Southwest Forestry University,Kunming Yunnan 650233,China;College of Chemical Engineering,Southwest Forestry University,Kunming Yunnan 650233,China;College of Materials Science and Engineering,Southwest Forestry University,Kunming Yunnan 650233,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650233 [2]西南林业大学化学工程学院,云南昆明650233 [3]西南林业大学材料科学与工程学院,云南昆明650233

出　　处：《西南林业大学学报（自然科学）》2022年第4期1-14,F0002,共15页Journal of Southwest Forestry University：Natural Sciences

基　　金：国家自然科学基金项目(51761036,52161016)资助;云南省基础研究计划杰出青年项目(202001AV070008)资助;云南省万人计划“青年拔尖人才”专项(51900109)资助。

摘　　要：采用回流提取法从农林废弃物核桃青皮制备出核桃青皮提取物(WGHE),利用失重法、动电位极化曲线、电化学阻抗谱和扫描电子显微镜(SEM)研究了WGHE与阴离子表面活性剂十二烷基苯磺酸钠(SDBS)对冷轧钢(CRS)在柠檬酸(H_(3)C_(6)H_(5)O_(7))溶液中的缓蚀协同效应。结果表明:WGHE、SDBS单独使用时均能一定程度抑制1.0 mol/L H_(3)C_(6)H_(5)O_(7)对钢的腐蚀,但最大缓蚀率低于60%。当WGHE和SDBS复配后对冷轧钢具有优良的缓蚀性能,最大缓蚀率可高达94.2%,缓蚀协同效应系数均大于1,两者之间发生了缓蚀协同作用;协同效应程度随WGHE浓度的增加而不断增强,但随温度的升高而下降,在浸泡时间为72 h和酸浓度为1.0 mol/L时达到峰值。WGHE、SDBS复配前后在钢表面的吸附行为均服从Langmuir吸附等温式,但复配后吸附平衡常数显著上升,而标准吸附Gibbs自由能更负。WGHE/SDBS为混合抑制型缓蚀剂,复配后使阴极和阳极反应腐蚀电流密度明显负移。EIS只有一个时间常数,其Nyquist图为单一弥散容抗弧,钢/酸界面的电荷转移电阻大小顺序为:WGHE/SDBS>WGHE>SDBS。SEM的微观形态证实了WGHE/SDBS复配缓蚀剂有效抑制了柠檬酸对钢表面的腐蚀,且表面粗糙度显著降低。WGHE中主要化学成分芦丁、槲皮素、1−甲基萘醌、胡桃醌与SDBS复配后也能发生协同作用,但协同效应强度弱于WGHE/SDBS。Walnut green husk extract(WGHE)was prepared by reflux method using forestry and agricultural residue of walnut green husk as the raw materials.The synergistic inhibition effect of WGHE and the anionic sur-factant of sodium dodecyl benzene sulfonate(SDBS)on the corrosion of cold rolled steel(CRS)in citric acid(H_(3)C_(6)H_(5)O_(7))solution was studied by weight loss,potentiodynamic polarization curves,electrochemical im-pedance spectroscopy(EIS)and scanning electron microscope(SEM).The results show that individual WGHE or SDBS can retard the corrosion of CRS surface in 1.0 mol/L H_(3)C_(6)H_(5)O_(7) solution to some extent.However,the maximum inhibition efficiency is below 60%for either individual WGHE or SDBS.Incorporation of WGHE with SDBS can obtain efficient inhibitive action,and the maximum inhibition efficiency can reach as high as 94.2%.All synergism parameters are higher than 1,and so there is a true synergistic inhibition effect between WGHE and SDBS.The synergistic inhibition increases with an increase of WGHE concentration,while decreases with an in-crease of temperature,and reaches a peak value with the acid concentration of 1.0 mol/L and the immersion time of 72 h.No matter whether WGHE is mixed with SDBS,the adsorption behavior on steel surface obeys Langmuir adsorption isotherm.The adsorption equilibrium constant of WGHE/SDBS mixture is increased evidently compar-ing with individual WGHE or SDBS.WGHE/SDBS is a mixed-type inhibitor,which shifts both cathodic and an-odic branches to negative corrosion current densities.EIS has only one time constant,and its Nyquist spectrum ex-hibits a depressed capacitive loop.The charge transfer resistance of steel/solution interface follows the order:WGHE/SDBS>WGHE>SDBS.SEM and AFM micrographs confirm that WGHE/SLS can efficiently alleviate the corrosion degree of steel surface in citric acid media,and the surface roughness is significantly dropped.There is a synergism between SDBS and the major components of rutin,quercetin,1-methylnaphoqinone and juglone in WGHE,

关 键 词：核桃青皮 提取物 十二烷基苯磺酸钠 缓蚀协同效应 柠檬酸 钢 吸附 

分 类 号：S713[农业科学—林学]