This study investigated the performance of commercial activated carbon modified with Ag/Fe nanoparticles for colour removal and chemical oxygen demand reduction from methylene blue dye wastewater under visible light irradiation. Central composite design of the response surface methodology was used to optimize the operating conditions with a minimum number of experiments. There are three operating variables namely adsorbent dosage (g) (1.5–3.5 g), pH of dye wastewater (pH 4–10) and contact time (min) (60–120 min) via a total 20 of experiments were carried out to optimize the combination effects of the parameters. In the Ag/Fe/CAC study, under optimum operating conditions of 1.79 g/L, pH 5.75 and 115 min of contact time, chemical oxygen demand reduction and colour removal were 37 and 94%, respectively. The error differences between predicted and experimental data were < ± 5%. The properties of Ag/Fe/CAC were characterized by Fourier transform infrared ray, X-ray diffraction and high-performance liquid chromatography analysis and scanning electron microscopy. The isotherm and kinetics study indicated that the experimental data fitted to Langmuir and pseudo-second-order models, respectively.

中文翻译：

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从亚甲基蓝染料废水中合成用于去除颜色和COD的Ag / Fe / CAC

这项研究调查了用Ag / Fe纳米粒子改性的商用活性炭在可见光照射下对亚甲基蓝染料废水的脱色和减少化学需氧量的性能。响应面方法的中央复合设计用于通过最少的实验来优化操作条件。通过总共20个实验，进行了三个操作变量，分别是吸附剂剂量（g）（1.5-3.5 g），染料废水的pH（pH 4-10）和接触时间（min）（60-120 min）。优化参数的组合效果。在Ag / Fe / CAC研究中，在1.79 g / L，pH 5.75和115分钟接触时间的最佳操作条件下，化学需氧量减少和脱色分别为37％和94％。预测数据与实验数据之间的误差差异为<±5％。通过傅里叶变换红外光谱，X射线衍射，高效液相色谱分析和扫描电子显微镜对Ag / Fe / CAC的性能进行了表征。等温线和动力学研究表明，实验数据分别拟合了Langmuir模型和伪二阶模型。