维生素在含氯混凝土模拟孔隙液中对钢筋的缓蚀作用  

Corrosion Effects of Vitamins on Steel Bar in Simulated PoreSolution of Concrete Containing Chlorine

作　　者：马欣眉 温勇[1] 田沛丰 林海孟 邵帅 MA Xinmei;WEN Yong;TIAN Peifeng;LIN Haimeng;SHAO Shuai(School of Civil Engineering and Architecture,Xinjiang University,Urumqi 830039,China;China Railway Ninth Bureau Group Fourth Engineering Co.,Ltd.,Shenyang 110013,China)

机构地区：[1]新疆大学建筑工程学院,乌鲁木齐830049 [2]中铁九局集团第四工程有限公司,沈阳110013

出　　处：《硅酸盐通报》2024年第6期2093-2101,共9页Bulletin of the Chinese Ceramic Society

基　　金：国家自然科学基金(52168036);绿色低碳建筑材料关键技术研究与应用(2022B03034-2)。

摘　　要：为研究钢筋混凝土体系中维生素缓蚀剂的缓蚀作用,本文采用动电位极化和电化学阻抗谱测试,研究了硫胺素(VitB1)、烟酸(VitB3)、吡哆醇(VitB6)和抗坏血酸(VitC)在含氯混凝土模拟孔隙液中对钢筋的缓蚀作用,并基于密度泛函理论进行了量子化学计算,讨论了维生素对钢筋的缓蚀机理。结果表明,在含0.05 mol/L NaCl的混凝土模拟孔隙液中,VitB6的缓蚀效果最好,因为其最高占据分子轨道和Fe 3d轨道间的键合稳定性最强。每种维生素都存在一个达到最佳缓蚀率IE的特定浓度添加值,此时VitB1和VitB3表现为阳极型缓蚀剂,VitB6和VitC为混合型缓蚀剂。随着维生素浓度的增加,IE出现反向波动的趋势,这是由于缓蚀剂的极性基团吸附于钢筋表面,抑制了阴极反应,进一步加剧了阴、阳极间的不平衡。In order to study the corrosion effect of vitamin corrosion inhibitor in reinforced concrete systems,the effects of thiamine(VitB1),nicotinic acid(VitB3),pyridoxine(VitB6)and ascorbic acid(VitC)on steel reinforcement in simulated pore solutions of concrete containing chlorine was investigated using dynamic potential polarization and electrochemical impedance spectroscopy tests.The mechanism of vitamin corrosion inhibition on steel reinforcement was also discussed based on density general function theory with quantum chemical calculations.The results show that VitB6 has the best corrosion inhibition effect in simulated pore solution of concrete containing 0.05 mol/L NaCl because of the strongest bonding stability between its highest occupied molecular orbital and the 3d orbital of iron.All four vitamins have a specific concentration value to achieve the best corrosion inhibition effect IE.At this time,VitB1 and VitB3 are anodic corrosion inhibitors and VitB6 and VitC are mixed corrosion inhibitors.With the increase of vitamin concentration,the IE tends to fluctuate inversely,which is due to the inhibition of cathodic reaction caused by the adsorption of polar groups on steel surface,further aggravating the imbalance between cathode and anode.

关 键 词：有机缓蚀剂 氯离子 电化学 混凝土模拟孔隙液 密度泛函理论 

分 类 号：TU528[建筑科学—建筑技术科学]