摘要
为了有效选择古代铁质文物的天然缓蚀剂,采用傅里叶变换红外光谱、X射线衍射、电化学阻抗谱、极化曲线和扫描电子显微镜研究了儿茶素在3.5 g/L NaCl溶液中对光滑表面和带锈表面过共晶白口铸铁的缓蚀保护效果。结果表明:儿茶素属于抑制阳极反应为主的缓蚀剂;儿茶素会与裸铸铁产生物理和化学复合吸附作用,与Fe;反应生成黑色非晶态的儿茶素铁,从而在NaCl溶液起到有效抑制铸铁腐蚀的作用;儿茶素与锈层中不稳定的γ-FeOOH反应,生成黑色非晶态惰性物质并沉积在锈层内,使原有锈层更加致密,更有效阻滞铸铁与腐蚀溶液之间的电荷和离子转移,提升对内部金属的保护效果。儿茶素可以作为一种天然的缓蚀稳定剂应用于古代铁质文物保护中,且应用前景广泛。
To effectively select natural corrosion inhibitors for archaeological iron objects,Fourier transform infrared spectroscopy,X-ray diffraction,electrochemical impedance spectroscopy,polarization curves and scanning electron microscopy were used to study the corrosion inhibition and protection effect of catechin in 3.5 g/L NaCl solution for naked and rusted hypereutectic white cast iron.The results show that catechin was a corrosion inhibitor that mainly inhibited anodic reaction.Catechin had both physical and chemical adsorption with the naked cast iron,and reacted with Fe;to form black amorphous ferric catechin which could effectively inhibit the corrosion in NaCl solution.Catechin reacted with the unstableγ-FeOOH in the rust layer,consuming and transforming into black amorphous product depositing in the rust layer.The product could make the original rust layer denser,with the ability to block the transfer of charges and ions more effectively between rusted cast iron and corrosive solution,and enhanced the protective effect of the internal metal.Catechin can be used as a natural corrosion inhibitor and stabilizer in the protection of ancient iron cultural heritage,and its application prospects will be broad.
作者
贾明浩
胡沛
胡钢
JIA Minghao;HU Pei;HU Gang(School of Archaeology and Museology,Peking University,Beijing 100871,China)
出处
《腐蚀与防护》
CAS
北大核心
2022年第1期1-7,共7页
Corrosion & Protection
基金
国家重点研发计划(2020YFC1522100)。
关键词
儿茶素
铸铁
缓蚀
文物保护
catechin
cast iron
corrosion inhibition
heritage conservation
