Departamento C.M., I.M. y Química Inorgánica, Universidad de Cádiz, Puerto Real 11510, Spain; Laboratoire Matériaux et Systèmes Interfaciaux LMSI, Faculté des Sciences, Université Abdelmalek Essaadi, 93000 Tétouan, Morocco.
Departamento C.M., I.M. y Química Inorgánica, Universidad de Cádiz, Puerto Real 11510, Spain; IMEYMAT, Instituto Universitario de Investigación en Microscopía Electrónica y Materiales, Universidad de Cádiz, Puerto Real 11510, Spain.
J Hazard Mater. 2019 Mar 5;365:519-530. doi: 10.1016/j.jhazmat.2018.11.037. Epub 2018 Nov 12.
Different natural Moroccan clays were used as adsorbents for the removal of lead from aqueous solution. The study was performed not only employing the starting clays in the form of powder but also after their extrusion as honeycomb monoliths, this representing the major novelty of this work respect to the current state-of-art. The experiments were done in batch conditions with continuous stirring and using a recirculated flow, respectively. In addition to an exhaustive characterization of the clays by means of X-ray fluorescence, X-ray diffraction, thermogravimetric analysis, laser granulometry, N physisorption, infrared spectroscopy, SEM-EDS and evaluation of the cation exchange capacity, special attention was paid to the influence on the lead adsorption of variables such as adsorbent dosage, pH, contact time with the adsorbate and initial concentration of lead. Considering the cheap and abundant character of the raw materials, their easy processing (no additives were required for their extrusion) and the time and energy save due to no need for further modification through chemical/thermal activation, the obtained results (with retention over 90% for 30 ppm of lead) demonstrated the potential of the proposed design as low cost solution that may be competitive versus other technologies for water depollution, especially in developing regions.
不同的天然摩洛哥粘土被用作吸附剂，以从水溶液中去除铅。这项研究不仅使用了粉末形式的起始粘土，还使用了挤出后的蜂窝状整体式粘土，这是相对于现有技术的主要新颖之处。实验在分批条件下进行，采用连续搅拌和循环流动。除了通过 X 射线荧光、X 射线衍射、热重分析、激光粒度分析、N 物理吸附、红外光谱、SEM-EDS 和阳离子交换能力评估对粘土进行全面表征外，还特别关注了吸附剂用量、pH 值、与吸附物接触时间和铅初始浓度等变量对铅吸附的影响。考虑到原材料的廉价和丰富特性、它们易于加工（挤出时不需要添加任何添加剂）以及由于无需通过化学/热激活进一步改性而节省的时间和能源，获得的结果（对 30ppm 的铅保留率超过 90%）表明了所提出设计作为低成本解决方案的潜力，可能具有竞争力与其他用于水净化的技术相比，特别是在发展中地区。
