Abstract

The corrosion inhibition property of the Uncaria gambir extract (UGE) for the low-carbon steel was investigated in a prepared cooling-water solution using gravimetric analysis and potentiodynamic polarization measurements. Anticorrosive effectiveness was tested at the UGE concentrations of 0–1500 ppm and temperatures of 40–60°C. The CaCO₃ scale inhibition performance was evaluated following NACE standard TM 0374-2007 and ASTM D511-03. The surface morphology was analyzed by scanning electron microscopy. It was found that increasing the UGE concentration increased its anticorrosive effectiveness. A 70% corrosion inhibition efficiency and a 31% CaCO₃ scale inhibition efficiency were observed during the use of 1500 ppm UGE. A change in the morphology of CaCO₃ precipitate was observed due to the adsorption of the UGE, which suppressed the regular growth process. Increasing temperature decreased the effectiveness of the UGE. A higher corrosion potential and a reduction of anodic reactivity were also observed. The UGE acted as anodic inhibitor and conformed the Langmuir adsorption isotherm.

中文翻译：

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浓度和温度对冷却水溶液中低碳钢钩藤提取物的腐蚀和阻垢行为的影响

摘要

使用重量分析和电位动力学极化测量，研究了制备的冷却水溶液中钩藤甘蓝提取物（UGE）对低碳钢的缓蚀性能。在0–1500 ppm的UGE浓度和40–60°C的温度下测试了防腐效果。根据NACE标准TM 0374-2007和ASTM D511-03评估CaCO ₃阻垢性能。通过扫描电子显微镜分析表面形态。发现增加UGE浓度可提高其防腐效果。在使用1500 ppm UGE期间，观察到70％的腐蚀抑制效率和31％的CaCO ₃垢抑制效率。CaCO形态的变化由于UGE的吸附，观察到_3个沉淀，抑制了正常的生长过程。温度升高降低了UGE的有效性。还观察到更高的腐蚀潜能和阳极反应性的降低。UGE充当阳极抑制剂并符合Langmuir吸附等温线。