溴代十六烷基吡啶对冷轧钢在柠檬酸中的缓蚀性能  

Inhibitive action of hexadecylpyridinium bromide on cold rolled steel in citric acid solution

作　　者：杨惠芳 雷然[1,2] 李向红 YANG Hui-fang;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：《应用化工》2022年第9期2575-2581,共7页Applied Chemical Industry

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

摘　　要：通过失重法、电化学阻抗谱(EIS)、动电位极化曲线和扫描电子显微镜(SEM)研究了溴代十六烷基吡啶(HDPB)在0.10 mol/L柠檬酸(H_(3)C_(6)H_(5)O_(7))溶液中对冷轧钢的缓蚀性能。结果表明,20℃时30 mg/L HDPB的缓蚀率为83.3%,缓蚀率与缓蚀剂浓度呈正相关,而与温度呈负相关,HDPB在冷轧钢表面遵循Langmuir吸附等温式,各温度的标准吸附Gibbs自由能(ΔG^(0))在-34~-29 kJ/mol范围,且吸附过程为标准吸附熵(ΔS^(0))减小的放热过程。HDPB为混合抑制型缓蚀剂,阴、阳两极的腐蚀电流密度随HDPB浓度增大而不断减小。Nyquist图谱由容抗弧和感抗弧构成,添加HDPB后电荷转移电阻增大。SEM微观形貌进一步证实了HPDB有效抑制了柠檬酸对冷轧钢表面的腐蚀。The inhibition effect of hexadecylpyridinium bromide(HDPB)on cold rolled steel(CRS)in 0.10 mol/H _(3)C _(6)H _(5)O_( 7) solution was studied by weight loss method,electrochemical impedance spectroscopy(EIS),potentiodynamic polarization curves and scanning electron microscope(SEM).The results indicate that HDPB the inhibition efficiency of 30 mg/L HDPB is up to 83.3%at 20℃.The inhibition efficiency was positively correlated with concentration,while negatively correlated with temperature.The adsorption of HDPB on CRS surface is in accordance with Langmuir adsorption isotherm.The standard adsorption Gibbs free energy(ΔG ^(0))values at different temperatures are within-34~-29 kJ/mol.The adsorption process is an exothermic reaction accompanying with the decrease of standard adsorption entropy(ΔS ^(0)).HDPB is a mixed type inhibitor,and the corrosion current densities of both cathodic and anodic reactions become much lower with an increase of inhibitor concentration.Nyquist diagram is composed of a capacitive loop followed by an inductive loop,and the charge transfer resistance significantly increases with the addition of HDPB.SEM micrographs indicate that HPDB can efficiently slow down the corrosion degree of CRS surface attacked by the aggressive media of citric acid.

关 键 词：溴代十六烷基吡啶 钢 缓蚀 柠檬酸 吸附 

分 类 号：TQ047.6[化学工程] TQ133.3