The Inhibitory Action of Aniba Canelilla (H. B. K.) Mez. Extracts on the Corrosion of Carbon Steel in Hydrochloric Acid Medium

The use of eco-friendly corrosion inhibitors in metallurgical processing has increased interest due to the reduced environmental impact. Hence, the inhibitory effect of Aniba canelilla (Lauraceae) extract was studied in the corrosion of carbon steel in 1.0 mol∙L-1 hydrochloric acid solution. This acid is used during the surface treatment of steel processing. The carbon steel protection was observed by varying the extract concentration from 50 to 300 mg∙L-1. Polarization curves revealed that this extract acted as an adsorption inhibitor decreasing both anodic and cathodic current densities. A relatively high inhibition corrosion efficiency, close to 97%, was obtained with plant stem extracts by gravimetric measurements. Weight loss measurements showed that the extract remains active for at least 72 hours at room temperature. The adsorption process of this extract is properly represented by the Langmuir isotherm. Atomic force microscopy shows that inhibited acid medium produces a smooth surface.

由于环保型缓蚀剂（eco-friendly corrosion inhibitors）对环境影响更小，其在冶金加工中的应用愈发受到关注。为此，本研究针对樟科（Lauraceae）植物Aniba canelilla提取物在1.0 mol∙L⁻¹盐酸溶液中对碳钢的腐蚀缓蚀效果展开探究。该盐酸常用于钢材加工的表面处理工序。通过将提取物浓度设置为50至300 mg∙L⁻¹，考察了其对碳钢的防护效果。极化曲线测试表明，该提取物属于吸附型缓蚀剂，可同时降低阳极与阴极电流密度。重量法测试结果显示，采用该植物茎秆提取物时可获得接近97%的较高缓蚀效率。失重法测试表明，该提取物在室温下至少可保持72小时的缓蚀活性。该提取物的吸附过程符合朗缪尔（Langmuir）吸附等温模型。原子力显微镜（Atomic Force Microscopy, AFM）观测结果显示，经缓蚀酸介质处理后的碳钢表面更为平整。