Okeniyi Joshua Olusegun, Ikotun Jacob Olumuyiwa, Akinlabi Esther Titilayo, Okeniyi Elizabeth Toyin
Mechanical Engineering Department, Covenant University, Ota 112001, Nigeria.
Department of Mechanical Engineering Science, University of Johannesburg, Johannesburg 2006, South Africa.
ScientificWorldJournal. 2019 Aug 19;2019:6894714. doi: 10.1155/2019/6894714. eCollection 2019.
This paper investigates anticorrosion behaviour of the bark-extract from L. on steel-rebar in concrete slabs in 3.5% NaCl medium of immersion (for simulating saline/marine environment). Corrosion-rate, corrosion-current, and corrosion-potential were measured from the NaCl-immersed steel-reinforced concrete cast with admixture of different plant-extract concentrations and from positive control concrete immersed in distilled water. Analyses indicate excellent mathematical-correlation between the corrosion-rate, concentration of the bark-extract admixture, and electrochemical noise-resistance (ratio of the corrosion-potential standard deviation to that of corrosion-current). The 0.4667% L. bark-extract admixture exhibited optimal corrosion-inhibition performance, = 99.08±0.11% (experimental) or = 97.89±0.24% (correlation), which outperformed the positive control specimens, experimentally. Both experimental and correlated results followed Langmuir adsorption isotherm which suggests prevalent physisorption mechanism by the plant-extract on the reinforcing-steel corrosion-protection. These findings support L. bark-extract suitability for corrosion-protection of steel-rebar in concrete structure designed for immersion in the saline/marine environmental medium.
本文研究了在3.5%氯化钠浸泡介质（用于模拟盐渍/海洋环境）中，L.树皮提取物对混凝土板中钢筋的防腐性能。从掺有不同植物提取物浓度的氯化钠浸泡钢筋混凝土以及浸泡在蒸馏水中的阳性对照混凝土中测量腐蚀速率、腐蚀电流和腐蚀电位。分析表明，腐蚀速率、树皮提取物掺合料浓度和电化学抗噪声性（腐蚀电位标准偏差与腐蚀电流标准偏差之比）之间存在良好的数学相关性。0.4667%的L.树皮提取物掺合料表现出最佳的缓蚀性能，实验值为η = 99.08±0.11%，相关值为η = 97.89±0.24%，实验结果优于阳性对照样本。实验结果和相关结果均遵循朗缪尔吸附等温线，这表明植物提取物在钢筋防腐保护方面普遍存在物理吸附机制。这些发现支持L.树皮提取物适用于设计用于浸泡在盐渍/海洋环境介质中的混凝土结构中钢筋的防腐保护。
