Department of Chemical Sciences, Mountain Top University, Pakuro, Ogun State, Nigeria.
Department of Chemistry, College of Science, University of Jeddah, Jeddah, Saudi Arabia.
Sci Rep. 2024 Oct 14;14(1):23957. doi: 10.1038/s41598-024-74627-7.
Pharmaceutical effluents generated during drugs production and application are often times released into the water systems with little or no treatment, which could pose potential danger to the ecosystem. Advanced oxidation processes for organic pollutants treatment have gained wide consideration due to their effectiveness. In this work, hydrogen peroxide (HO) and hydrogen peroxide-supported nano zerovalent iron (HO@nZVIs) were deployed to study pharmaceutical effluents (PE) degradation via batch experiments, under various reaction time, (HO) and (HO@nZVIs) concentrations, pH, PE concentration, and temperature. The nZVIs was prepared from the green synthesis of Vernonia amygdalina leaf extract and characterized using different analytical tools such as Fourier Transform-Infrared Spectroscopy (FT-IR), Gas Chromatography Mass Spectroscopy (GC-MS), Scanning Electron Microscopy (SEM), and X-Ray Diffraction Spectroscopy (XRD). The FT-IR results showed the presence of -C = O, -NH, -OH, -C = C and, -C-O functional groups, SEM report showed that the morphology of the nZVIs is round in shape, while GC-MS revealed the presence of several phytochemicals. When the concentration of the effluent was increased from 10 to 30 ml, the percentage decolourization decreased from 74.74 to 51.96% and from 80.36 to 54.38% for HO and HO@nZVI respectively, whereas when the contact time was increased from 10 to 60 min, the percentage decolourization rose from 70.39 to 83.49% for HO and from 85.19 to 89.73% when HO@nZVI was used. When the effect of pH was assessed, it was observed that on increasing the pH from 2 to 10, the percentage decolourization rose from 74.5 to 80.25% for HO, however, with HO@nZVI, the percentage decolourization decreased from 81.50 to 68%. Maximum percentage decolourization of 57.10% and 94.56% for HO and HO@nZVI was achieved at catalyst volume of 25 ml. For all the parameters tested, the HO@nZVIs performed much better indicating that the nZVIs enhanced the decolourization ability of the HO. The kinetic results showed that the decolorization of pharmaceutical effluent by both catalysts fitted very well with the second-order model, while thermodynamic properties of enthalpy change were found to be 10.025 and 27.005 kJ/mol/K for HO and HO@nZVIs respectively suggesting that the oxidation process is endothermic in nature. This technique employed in using hydrogen peroxide-supported zero valent iron, proved to be highly efficient not only for pharmaceutical effluent degradation but also in the elimination of lead from the effluent.
制药生产和应用过程中产生的药物废水通常未经处理就排放到水系中，这可能对生态系统构成潜在威胁。由于其有效性，高级氧化工艺在有机污染物处理方面得到了广泛的关注。在这项工作中，过氧化氢（HO）和过氧化氢负载的纳米零价铁（HO@nZVIs）被用于通过批处理实验研究药物废水（PE）的降解，在不同的反应时间、（HO）和（HO@nZVIs）浓度、pH 值、PE 浓度和温度下进行。nZVIs 是通过 Vernonia amygdalina 叶提取物的绿色合成制备的，并使用不同的分析工具进行了表征，如傅里叶变换红外光谱（FT-IR）、气相色谱质谱联用（GC-MS）、扫描电子显微镜（SEM）和 X 射线衍射光谱（XRD）。FT-IR 结果表明存在-C=O、-NH、-OH、-C=C 和-C-O 官能团，SEM 报告显示 nZVIs 的形态为圆形，而 GC-MS 则表明存在几种植物化学物质。当废水浓度从 10 增加到 30ml 时，HO 和 HO@nZVI 的脱色率分别从 74.74%下降到 51.96%和从 80.36%下降到 54.38%，而当接触时间从 10 增加到 60min 时，HO 的脱色率从 70.39%上升到 83.49%，而当使用 HO@nZVI 时，HO@nZVI 的脱色率从 85.19%上升到 89.73%。当评估 pH 的影响时，观察到随着 pH 值从 2 增加到 10，HO 的脱色率从 74.5%上升到 80.25%，然而，对于 HO@nZVI，脱色率从 81.50%下降到 68%。HO 和 HO@nZVI 的最大脱色率分别为 57.10%和 94.56%，催化剂体积为 25ml。对于所有测试的参数，HO@nZVIs 的表现要好得多，表明 nZVIs 增强了 HO 的脱色能力。动力学结果表明，两种催化剂对药物废水的脱色均非常符合二级模型，而焓变的热力学性质分别为 10.025 和 27.005kJ/mol/K，表明氧化过程本质上是吸热的。这种使用过氧化氢负载零价铁的技术不仅在药物废水降解方面，而且在从废水中去除铅方面都被证明是非常有效的。
