Centre of Environmental Studies, Institute of Inter-Disciplinary Studies, University of Allahabad, Prayagraj, Uttar Pradesh, 211002, India.
Department of Chemistry, Faculty of Science, University of Allahabad, Prayagraj, Uttar Pradesh, 211002, India.
Environ Sci Pollut Res Int. 2024 Sep;31(43):55317-55335. doi: 10.1007/s11356-024-34799-1. Epub 2024 Sep 3.
This work involved the preparation of pristine and iron nanoparticle-loaded biochar from a water chestnut shell to remove diclofenac sodium (DCF) containing effluent of pharmaceutical origin. To create suitable forecasting equations for the modelling of the DCF adsorption onto the adsorbent, response surface methodology (RSM) was used. The parameters, e.g. pH, adsorbent mass, DCF concentration and contact time, were used for the modeling of adsorption. The RSM model predicts that for 98.0% DCF removal, the ideal conditions are pH 6, an adsorbent dose of 0.5 g L, and a contact time of 60 min with an initial adsorbate concentration of 25 mg L at 303 K. The maximum capacity deduced from the Langmuir model was 75.9 mg g for pristine water chestnut shell biochar (pWCBC) and 122.3 mg g for magnetically modified nano-FeO biochar (mWCBC). Under equilibrium conditions, the Langmuir model was the best-suited model compared to the Temkin and Freundlich models. The adsorption data in this investigation efficiently fitted the pseudo-second-order model, emphasizing that chemisorption or ion exchange processes may be involved in the process. The WCBC demonstrated recyclability after 10 cycles of repeated adsorption and desorption of DCF. A combined coagulation adsorption process removed COD, NH-N, NO, PO, and DCF by 92.50%, 86.41%, 77.57%, 84.54%, and 97.25%, respectively. This study therefore shows that coagulation followed by adsorption onto biochar can be a cost-effective substitute for conventional pharmaceutical wastewater treatment.
这项工作涉及从马蹄壳中制备原始和负载铁纳米粒子的生物炭，以去除含药物来源的双氯芬酸钠（DCF）废水。为了创建适合预测方程，以便对吸附剂上的 DCF 吸附进行建模，使用响应面法（RSM）。使用参数（例如 pH、吸附剂质量、DCF 浓度和接触时间）对吸附进行建模。RSM 模型预测，为了达到 98.0%的 DCF 去除率，理想条件是 pH 值为 6、吸附剂剂量为 0.5 g/L、接触时间为 60 min，初始吸附质浓度为 25 mg/L，温度为 303 K。从 Langmuir 模型推断出的最大容量为 75.9 mg/g 的原始马蹄壳生物炭（pWCBC）和 122.3 mg/g 的磁性修饰纳米-FeO 生物炭（mWCBC）。在平衡条件下，与 Temkin 和 Freundlich 模型相比，Langmuir 模型是最合适的模型。与 Temkin 和 Freundlich 模型相比，吸附数据更适合伪二阶模型，这表明可能涉及化学吸附或离子交换过程。在重复吸附和解吸 DCF 10 次后，WCBC 表现出可回收性。混凝吸附联合工艺分别去除了 92.50%、86.41%、77.57%、84.54%和 97.25%的 COD、NH-N、NO、PO 和 DCF。因此，这项研究表明，混凝后吸附到生物炭上可以作为传统药物废水处理的一种经济有效的替代方法。
