Chauhan Dheeraj Singh, Mazumder M A Jafar, Quraishi M A, Ansari K R
Center of Research Excellence in Corrosion, Research Institute, King Fahd University of Petroleum and Minerals, Dhahran 31261, Saudi Arabia.
Chemistry Department, King Fahd University of Petroleum and Minerals, Dhahran 31261, Saudi Arabia.
Int J Biol Macromol. 2020 Apr 26. doi: 10.1016/j.ijbiomac.2020.04.200.
A Schiff base of chitosan with cinnamaldehyde (Cinn-Cht) was synthesized in a single step using microwave irradiation and characterized using spectroscopic techniques. The synthesized Schiff base was used for the mitigation of carbon steel corrosion in 15% HCl. The corrosion evaluation was performed using weight loss tests, electrochemical impedance measurements, and polarization studies. The corrosion inhibition efficiency increased with inhibitor dosage and achieved a high value of 85.16% at 400 mgL. The inhibitor adsorption followed the Langmuir isotherm and displayed a mixed physical and chemical adsorption behavior. To further improve the corrosion inhibition efficiency, potassium iodide (KI) was incorporated in the corrosive solution, which increased the inhibition efficiency further to 92.45% at a concentration of 10 mM. Surface studies carried out via SEM analyses indicated the inhibitor adsorption and protective film formation on the steel surface. The computational studies carried out via DFT revealed that mainly the protonated form of inhibitor adsorbs on the metal surface. Monte Carlo simulation studies also showed that the protonated form of the inhibitor molecule exhibited higher adsorption energy than the neutral inhibitor.
采用微波辐射一步合成了壳聚糖与肉桂醛的席夫碱（Cinn-Cht），并用光谱技术对其进行了表征。合成的席夫碱用于减轻15%盐酸中碳钢的腐蚀。采用失重试验、电化学阻抗测量和极化研究进行腐蚀评估。缓蚀效率随缓蚀剂用量的增加而提高，在400mg/L时达到85.16%的高值。缓蚀剂吸附遵循朗缪尔等温线，表现出物理和化学混合吸附行为。为进一步提高缓蚀效率，在腐蚀溶液中加入碘化钾（KI），在10mM浓度下，缓蚀效率进一步提高到92.45%。通过扫描电子显微镜分析进行的表面研究表明，缓蚀剂在钢表面吸附并形成保护膜。通过密度泛函理论进行的计算研究表明，主要是缓蚀剂的质子化形式吸附在金属表面。蒙特卡罗模拟研究还表明，缓蚀剂分子的质子化形式比中性缓蚀剂表现出更高的吸附能。
