Green synthesis of bentonite-iron nanoparticles (Be-FeNPs) has been carried out using the leaf extract of Helicteres isora and its antibacterial and adsorption capacity for the removal of Methyl Blue (MB) dye have been also studied.T he prepared Be-FeNPs and iron nanoparticles (FeNPs) are characterized by UV-visible, FTIR spectroscopic techniques and SEM analysis. The antibacterial activity of Be-FeNPs show good zone of inhibition against E.coli and S.aureus. Further the prepared composite (Be-FeNPs) and bentonite are used as adsorbents for the removal of Methyl Blue (MB) dye in aqueous solution under various experiment parameters like initial concentration, contact time and pH. The optimum initial pH, adsorbent concentration and time were determined to be 8.1, 45°C, and 100 ppm, 80 min for MB adsorption on to Be-FeNPs. The experimental data for MB adsorption fits well to the Freundlich and Langmuir isotherm models. The kinetic equations like Natarajan-Khalaf, Bhattacharya-Venkobachar and Lagergren equations were found to be applicable. The surface morphology of the Be-FeNPs before and after adsorption of dye revealed that it can be used as an excellent adsorbent for dye removal from dilute industrial effluents.

中文翻译：

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膨润土-铁纳米粒子的合成、抗菌活性及吸附研究去除甲基蓝染料

【摘要】：利用异叶菊叶提取物绿色合成膨润土-铁纳米粒子(Be-FeNPs),并研究了其对甲基蓝(MB)染料的抗菌和吸附能力。制备Be-FeNPs和铁纳米颗粒 (FeNPs) 通过紫外可见、FTIR 光谱技术和 SEM 分析进行表征。Be-FeNPs的抗菌活性对大肠杆菌和金黄色葡萄球菌具有良好的抑制作用。此外，制备的复合材料（Be-FeNPs）和膨润土用作吸附剂，用于在初始浓度、接触时间和 pH 等各种实验参数下去除水溶液中的甲基蓝（MB）染料。MB 吸附到 Be-FeNPs 上的最佳初始 pH、吸附剂浓度和时间确定为 8.1、45°C 和 100 ppm、80 分钟。MB 吸附的实验数据非常符合 Freundlich 和 Langmuir 等温线模型。发现像 Natarajan-Khalaf、Bhattacharya-Venkobachar 和 Lagergren 方程这样的动力学方程是适用的。Be-FeNPs 吸附染料前后的表面形貌表明，它可以用作从稀释的工业废水中去除染料的优良吸附剂。