壳寡糖对Q235钢在海水中的缓蚀性能

摘要

The corrosion inhibition of chio-oligosaccharide (COS) and compound inhibitors of COS and inorganic inhibitors to Q235 steel in seawater was investigated by corrosion immersion test,scanning electron microscopy (SEM) and electrochemical experimental methods.The electrochemical experimental results show that the inhibition efficiency hit the maximum of 65.73％ when COS was added individually.The synergetic inhibition efficiency of COS compounded with NaNO2 in seawater was 90.67％,and this compound inhibitor exhibited anodic type.The largest synergetic inhibition efficiency of COS compounded with Na2MoO4 was only 71.65％,and the COS and Na2 MoO4 inhibited mutually.In corrosion immersion test the inhibition efficiency was the best with the value of 85.90％,when COS was compounded with NaNO2.The mechanism of COS on the surface of Q235 steel was monomolecular adsorption,a spontaneous chemisorption process.The absorption of COS on the surface of Q235 steel obeyed the Langmuir model.%采用腐蚀浸泡试验,扫描电子显微镜以及电化学试验法等研究了海水中壳寡糖(COS)及其与无机缓蚀剂复配后对Q235钢的缓蚀作用.电化学试验结果表明:单独添加COS时,缓蚀率最大为65.73％;当COS与NaNO2复配添加时,其协同缓蚀率为90.67％,为阳极型缓蚀剂;而当COS与Na2MoO4复配时,缓蚀率最大只能达到71.65％,且两者发生了抑制作用.腐蚀浸泡试验结果表明:当COS与NaNO2复配使用时,其缓蚀率最佳,为85.90％.COS在Q235钢表面发生单分子吸附,为自发进行的化学吸附,从而起到缓蚀作用,该吸附符合Langmuir模型.