Chauhan Dheeraj Singh, Mazumder M A Jafar, Quraishi M A, Ansari K R, Suleiman R K
Center of Research Excellence in Corrosion, 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 25;158:231-243. doi: 10.1016/j.ijbiomac.2020.04.195.
A new Schiff base of chitosan, namely Piperonal-chitosan (Pip-Cht), was synthesized for the first time, using a microwave irradiation method and characterized using spectroscopic techniques. The corrosion inhibition behavior of the new Schiff base was evaluated on carbon steel in 15% HCl medium via gravimetric and electrochemical techniques. This is the first work on the application of chemically functionalized chitosan as a corrosion inhibitor in the oil-well acidizing environment. The Pip-Cht inhibitor exhibited a high corrosion inhibition efficiency of 85.16% at a moderate dose of 600 mg L. Further, the addition of potassium iodide as a synergistic agent to the corrosive electrolyte produced a significant improvement in the inhibition efficiency to 91.15% at a low dosage of 10 mM of KI. At a higher temperature of 65 °C, the combination of both the inhibitor and KI yielded a high inhibition efficiency. The results of the gravimetric and electrochemical experiments were corroborated using AFM and SEM studies. The DFT calculations indicated that corrosion inhibition behavior of the Schiff base mainly occurs in the protonated form.
首次采用微波辐射法合成了一种新型壳聚糖席夫碱，即胡椒醛 - 壳聚糖（Pip - Cht），并采用光谱技术对其进行了表征。通过重量法和电化学技术评估了这种新型席夫碱在15%盐酸介质中对碳钢的缓蚀性能。这是首次将化学功能化壳聚糖作为油井酸化环境中的缓蚀剂进行应用的研究。Pip - Cht缓蚀剂在600 mg/L的适中剂量下表现出85.16%的高缓蚀效率。此外，向腐蚀性电解质中添加碘化钾作为增效剂，在10 mM碘化钾的低剂量下，缓蚀效率显著提高至91.15%。在65°C的较高温度下，缓蚀剂和碘化钾的组合产生了较高的缓蚀效率。通过原子力显微镜（AFM）和扫描电子显微镜（SEM）研究证实了重量法和电化学实验的结果。密度泛函理论（DFT）计算表明，席夫碱的缓蚀行为主要以质子化形式发生。
