Martínez Alfonso, Tarso Paulo, Ribeiro Glauco H, Costa Letícia M, Pinheiro Fernanda C, Oliveira Nathália R, Vargas Julio C, Sinisterra Rubén D
Graduate Program of Technological Innovation-concentration Area: New Materials, Nanotechnology and Chemistry, Federal University of Minas Gerais, Belo Horizonte, MG, ZIP: 31270-901, Brazil; Chemical and Environmental Engineering Department, Universidad Nacional de Colombia - Sede Bogotá, Bogotá, D.C., ZIP: 111321, Colombia.
Chemistry Department, Exact Sciences Institute, Universidade Federal de Minas Gerais, Belo Horizonte, MG, 31270-901, Brazil.
Talanta. 2025 Feb 1;283:127103. doi: 10.1016/j.talanta.2024.127103. Epub 2024 Oct 24.
To remediate surface water as the Doce River and spring waters from Minas Gerais, Brazil, this study examined the possibility of natural serpentinite mining tailings as a sustainable alternative for removing aluminum (III), iron (III), and manganese (II). The study used a Box-Behnken experimental design to examine how initial metal concentration, adsorbate dosage, and adsorption time affect metal removal effectiveness. Results demonstrated impressive performance, with removal rates exceeding 80 % for Al(III) and Fe(III) within the initial 5 min, and 60 % for Mn(II) within 30 min. This study delves deeper into the removal mechanisms, kinetics, adsorption isotherms and characterization identify physisorption and chemisorption pathways in which complex formation with released OH groups and ion exchange with Mg(II) from serpentinite emerged as key contributors to the removal process. Furthermore, ion metal adsorption and regeneration cycles were assessed, exhibit sustained removal efficacy without notable capacity reduction. Each cycle shows an average metal adsorption capacity of 0.32 mg g and an average Mg(II) release capacity of 0.98 mg g. Remarkably, the application of serpentinite successfully lowered the metals content of the Doce River and spring water to drinkable standards. A batch and continuous process is proposed for scaling-up serpentinite's metal adsorption. Overall, this study shows serpentinite's potential as a foundation for sustainable and cost-effective methods to treat surface water contamination with Al(III), Fe(III), and Mn(II).
为了治理像巴西米纳斯吉拉斯州的多西河地表水和泉水，本研究探讨了利用天然蛇纹石矿尾矿作为去除铝（III）、铁（III）和锰（II）的可持续替代方案的可能性。该研究采用Box-Behnken实验设计，以考察初始金属浓度、吸附剂用量和吸附时间如何影响金属去除效果。结果显示出令人印象深刻的性能，在最初5分钟内，Al（III）和Fe（III）的去除率超过80%，30分钟内Mn（II）的去除率达到60%。本研究更深入地探究了去除机制、动力学、吸附等温线，并通过表征确定了物理吸附和化学吸附途径，其中与释放的OH基团形成络合物以及与蛇纹石中的Mg（II）进行离子交换是去除过程的关键因素。此外，还评估了离子金属吸附和再生循环，结果表明其具有持续的去除效果且容量没有明显降低。每个循环的平均金属吸附容量为0.32 mg/g，平均Mg（II）释放容量为0.98 mg/g。值得注意的是，蛇纹石的应用成功将多西河和泉水的金属含量降低到了可饮用标准。提出了一种分批和连续的工艺来扩大蛇纹石的金属吸附规模。总体而言，本研究表明蛇纹石有潜力成为一种可持续且经济高效的方法，用于处理受Al（III）、Fe（III）和Mn（II）污染的地表水。
