Dotti Anna, Guagliano Marianna, Ferretti di Castelferretto Vittorio, Scotti Roberto, Pedrazzi Simone, Puglia Marco, Orrù Romano V A, Cristiani Cinzia, Finocchio Elisabetta, Basso Peressut Andrea, Latorrata Saverio
Department of Chemistry, Materials and Chemical Engineering "Giulio Natta", Politecnico di Milano, Piazza Leonardo Da Vinci 32, 20133 Milano, Italy.
Department of Organic Chemistry, Aachen-Maastricht Institute for Biobased Materials (AMIBM), Maastricht University, Urmonderbaan 22, 6167 KD Geleen, The Netherlands.
Molecules. 2025 Apr 30;30(9):1997. doi: 10.3390/molecules30091997.
Adsorption is one of the simplest and most cost-effective techniques for water decontamination. In this field, biochar has recently emerged as a promising alternative to traditional adsorbents, exhibiting a high surface area and affinity to metal ions, as well as often being waste-derived. Similarly, reduced graphene oxide (rGO) shows an excellent adsorption capacity. Having self-assembling properties, it has already been employed to obtain self-standing heavy-metal-adsorbing membranes. In this research, a novel self-standing membrane of biochar and rGO is presented. It was obtained through an eco-friendly method, consisting of the simple mechanical mixing of the two components, followed by vacuum filtration and mild drying. Vine pruning biochar (VBC) was employed in different rGO/biochar mass ratios, ranging from 1/1 to 1/9. The best compromise between membrane integrity and biochar content was achieved with a 4/6 proportion. This sample was also replicated using chestnut-shell-derived biochar. The composite rGO-biochar membranes were characterized through XRD, FTIR-ATR, TG-DTG, SEM-EDX, BET, ZP, particle dimension, and EPR analyses. Then, they were tested for metal ion adsorption with 10 mM Cu and 100 mM Zn aqueous solutions. The adsorption capacity of copper and zinc was found to be in the range of 1.51-4.03 mmol g and 18.16-21.99 mmol g, respectively, at an acidic pH, room temperature, and contact time of 10 min. Interestingly, the composite rGO-biochar membranes exhibited a capture behavior between that of pure rGO and VBC.
吸附是水净化最简单且最具成本效益的技术之一。在该领域，生物炭最近已成为传统吸附剂的一种有前景的替代品，具有高比表面积和对金属离子的亲和力，且通常来源于废弃物。同样，还原氧化石墨烯（rGO）显示出优异的吸附能力。由于具有自组装特性，它已被用于制备自立式重金属吸附膜。在本研究中，提出了一种新型的生物炭与rGO自立式膜。它是通过一种环保方法制备的，该方法包括将两种组分简单机械混合，然后进行真空过滤和温和干燥。采用了不同rGO/生物炭质量比（范围从1/1到1/9）的葡萄修剪生物炭（VBC）。当比例为4/6时，在膜完整性和生物炭含量之间实现了最佳折衷。该样品还用栗壳衍生生物炭进行了复制。通过XRD、FTIR-ATR、TG-DTG、SEM-EDX、BET、ZP、颗粒尺寸和EPR分析对复合rGO-生物炭膜进行了表征。然后，用10 mM铜和100 mM锌的水溶液对它们进行金属离子吸附测试。在酸性pH、室温及10分钟接触时间下，发现铜和锌的吸附容量分别在1.51 - 4.03 mmol/g和18.16 - 21.99 mmol/g范围内。有趣的是，复合rGO-生物炭膜表现出介于纯rGO和VBC之间的捕获行为。
