Hamdy Ahmed, Mostafa Mohamed K, Nasr Mahmoud
Sanitary and Environmental Engineering Research Institute, Housing and Building National Research Center, Giza, Egypt.
Environmental Engineering Program, Zewail City of Science and Technology, 6th October City, Giza, Egypt E-mail:
Water Sci Technol. 2018 Aug;78(1-2):367-378. doi: 10.2166/wst.2018.306.
Nanoscale zero-valent iron (nZVI) particles were investigated for the removal of methylene blue (MB) from aqueous solutions and the treatment of textile industry effluents. The nZVI material was characterized by XRD, TEM, EDS, FTIR, and SEM. It was demonstrated that several functional groups such as C-H, C = C, C-C, and C-O contributed to MB reduction. At initial MB concentration of 70 mg/L, the optimum pH was 6, achieving a removal efficiency of 72.1% using an nZVI dosage of 10 g/L, stirring rate of 150 rpm, and temperature of 30 °C within 30 min. The adsorption isotherm was described by the Langmuir model with monolayer coverage of 5.53 mg/g, and the Freundlich equation with multilayer adsorption capacity of 1.59 (mg/g)·(L/mg). The removal mechanisms of MB included reduction into colorless leuco-MB, precipitation as Fe(II)-MB, adsorption as ZVI-MB or FeOOH-MB, and/or degradation using OH radicals. The synthesized nZVI particles were applied to reduce various organic and inorganic compounds, as well as heavy metal ions from real textile wastewater samples. The removal efficiencies of COD, BOD, TN, TP, Cu, Zn, and Pb reached up to 91.9%, 87.5%, 65.2%, 78.1%, 100.0%, 29.6%, and 99.0%, respectively. The treatment cost of 1 m of textile wastewater was estimated as 1.66 $USD.
研究了纳米零价铁（nZVI）颗粒对水溶液中亚甲基蓝（MB）的去除以及纺织工业废水的处理。通过X射线衍射（XRD）、透射电子显微镜（TEM）、能谱分析（EDS）、傅里叶变换红外光谱（FTIR）和扫描电子显微镜（SEM）对nZVI材料进行了表征。结果表明，诸如C-H、C = C、C-C和C-O等几个官能团有助于MB的还原。在初始MB浓度为70 mg/L时，最佳pH值为6，在30分钟内使用10 g/L的nZVI剂量、150 rpm的搅拌速率和30°C的温度，去除效率达到72.1%。吸附等温线用单层覆盖量为5.53 mg/g的朗缪尔模型和多层吸附容量为1.59（mg/g）·（L/mg）的弗伦德利希方程描述。MB的去除机制包括还原为无色的隐色体MB、以Fe（II）-MB形式沉淀、以ZVI-MB或FeOOH-MB形式吸附和/或利用羟基自由基降解。合成的nZVI颗粒用于还原实际纺织废水样品中的各种有机和无机化合物以及重金属离子。化学需氧量（COD）、生化需氧量（BOD）、总氮（TN）、总磷（TP）、铜（Cu）、锌（Zn）和铅（Pb）的去除效率分别达到91.9%、87.5%、65.2%、78.1%、100.0%、29.6%和99.0%。估计处理1立方米纺织废水的成本为1.66美元。
