Bashir Hamna, Niazi Nabeel Khan, Saqib Zulfiqar Ahmad, Hussain Khalid
Institute of Soil and Environmental Sciences, University of Agriculture Faisalabad, Faisalabad, Pakistan.
Department of Agronomy, University of Agriculture Faisalabad, Faisalabad, Pakistan.
Int J Phytoremediation. 2025 Jun 28:1-11. doi: 10.1080/15226514.2025.2522303.
The overarching aim of the current study was to synthesize nanoparticulate iron oxides (NP-FeOx; nano-magnetite (n-Mg), nano-goethite (n-Gh), nano-ferrihydrite (n-Fh), nano-hematite (n-Ht)) and develop rice husk biochar/NP-FeOx-based composites (BC/NP-FeOx) to remove hexavalent chromium (Cr(VI)) from contaminated water. Batch sorption experiments revealed that Cr removal efficiency was in the order: n-Gh (97.5%) > n-Mg (95.8%) > n-Fh (94.1%) > n-Ht (79.5%) at pH 7.0, sorbent dose of 0.5 g L and C = 12 mg L. Desorption studies showed the reusability of n-Gh and n-Mg over three cycles (65%-70%). Hence, both the most promising NP-FeOx were integrated with rice husk biochar to fabricate novel BC/n-Gh and BC/n-Mg composites and examined in column experiments for Cr(VI) removal at low and high Cr concentrations (3 and 10 mg L). High Cr(VI) removal efficiencies (up to 97%-99%) were obtained by both BC/NP-FeX composites across different time intervals (0-72 h). FTIR spectroscopy showed that Cr(VI) sorption was mainly governed by -OH anion exchange and interactions with -C-H, -C = O, and -Fe-O functional groups. This study highlights the significance of BC/n-Gh and BC/n-Mg composites in removing Cr(VI) from contaminated water, providing a suitable and sustainable solution for Cr treatment in wastewater.
本研究的总体目标是合成纳米颗粒氧化铁（NP-FeOx；纳米磁铁矿（n-Mg）、纳米针铁矿（n-Gh）、纳米水铁矿（n-Fh）、纳米赤铁矿（n-Ht）），并开发基于稻壳生物炭/NP-FeOx的复合材料（BC/NP-FeOx），以去除受污染水中的六价铬（Cr(VI)）。批量吸附实验表明，在pH值为7.0、吸附剂剂量为0.5 g/L且C = 12 mg/L的条件下，Cr的去除效率顺序为：n-Gh（97.5%）> n-Mg（95.8%）> n-Fh（94.1%）> n-Ht（79.5%）。解吸研究表明，n-Gh和n-Mg在三个循环中的可重复使用性为65%-70%。因此，将这两种最有前景的NP-FeOx与稻壳生物炭结合，制备了新型的BC/n-Gh和BC/n-Mg复合材料，并在柱实验中检测了它们在低Cr浓度和高Cr浓度（3和10 mg/L）下对Cr(VI)的去除效果。两种BC/NP-FeX复合材料在不同时间间隔（0-72 h）内均获得了较高的Cr(VI)去除效率（高达97%-99%）。傅里叶变换红外光谱（FTIR）显示，Cr(VI)的吸附主要受-OH阴离子交换以及与-C-H、-C=O和-Fe-O官能团相互作用的控制。本研究突出了BC/n-Gh和BC/n-Mg复合材料在去除受污染水中Cr(VI)方面的重要性，为废水中Cr的处理提供了一种合适且可持续的解决方案。
