Monaci Sharon, Minudri Daniela, Guazzelli Lorenzo, Mezzetta Andrea, Mecerreyes David, Forsyth Maria, Somers Anthony
POLYMAT, University of the Basque Country UPV/EHU, 20018 Donostia-San Sebastian, Spain.
Institute for Frontier Materials, Deakin University, Burwood, VIC 3125, Australia.
Molecules. 2023 Jul 21;28(14):5568. doi: 10.3390/molecules28145568.
Corrosion is a significant problem that negatively affects a wide range of structures and buildings, resulting in their premature failure, which causes safety hazards and significant economic loss. For this reason, various approaches have been developed to prevent or minimize the effects of corrosion, including corrosion inhibitors. Recently, biobased inhibitors have gained a certain interest thanks to their unique properties, eco-friendliness, and availability. Among all the green precursors, lignin is of particular interest, being a natural polymer that can be obtained from different sources including agricultural residues. Corrosion inhibitors based on ionic liquids (ILs) also present interesting advantages, such as low volatility and high tunability. If combined, it may be possible to obtain new lignin-based ILs that present interesting corrosion inhibitor properties. In this work, the inhibition properties of new biobased lignin ILs and the influence of anions and cations on the corrosion of mild steel in an aqueous solution of 0.01 M NaCl were investigated by Potentiostatic Electrochemical Impedance Spectroscopy (PEIS) and Cyclic Potentiodynamic Polarization (CPP). Moreover, the surface was characterized using SEM, EDS, and optical profilometry. The IL choline syringate showed promising performance, reducing the corrosion current after 24 h immersion in 0.01 M sodium chloride, from 1.66 µA/cm for the control to 0.066 µA/cm with 10 mM of the IL present. In addition to its performance as a corrosion inhibitor, both components of this IL also meet or exceed the current additional desired properties of such compounds, being readily available, and well tolerated in organisms and the environment.
腐蚀是一个严重的问题，会对广泛的结构和建筑物产生负面影响，导致其过早失效，从而造成安全隐患和重大经济损失。因此，人们开发了各种方法来预防或最小化腐蚀的影响，包括腐蚀抑制剂。最近，基于生物的抑制剂因其独特的性能、生态友好性和可得性而受到了一定的关注。在所有绿色前体中，木质素特别受关注，它是一种天然聚合物，可以从包括农业残余物在内的不同来源获得。基于离子液体（ILs）的腐蚀抑制剂也具有有趣的优势，如低挥发性和高可调性。如果将它们结合起来，有可能获得具有有趣腐蚀抑制性能的新型木质素基离子液体。在这项工作中，通过恒电位电化学阻抗谱（PEIS）和循环电位动力学极化（CPP）研究了新型生物基木质素离子液体的抑制性能以及阴离子和阳离子对低碳钢在0.01 M NaCl水溶液中腐蚀的影响。此外，使用扫描电子显微镜（SEM）、能谱仪（EDS）和光学轮廓仪对表面进行了表征。离子液体胆碱丁香酸盐表现出了良好的性能，在0.01 M氯化钠中浸泡24小时后，腐蚀电流从对照的1.66 µA/cm降低到存在10 mM该离子液体时的0.066 µA/cm。除了作为腐蚀抑制剂的性能外，这种离子液体的两种成分也满足或超过了此类化合物目前的其他期望性能，即易于获得，并且在生物体和环境中具有良好的耐受性。
