Laboratorio de Investigación en Biopolímeros y Metalofármacos, Facultad de Ciencias, Escuela Profesional de Química, Universidad Nacional de Ingeniería, Av. Túpac Amaru 210, Lima 25, Peru.
Laboratório de Ressonância Magnética Nuclear, Departamento de Química, Universidade Federal de São Carlos, São Paulo CP 676, 13565-905 São Carlos, São Paulo, Brazil.
Int J Biol Macromol. 2021 Feb 1;169:130-142. doi: 10.1016/j.ijbiomac.2020.12.022. Epub 2020 Dec 7.
Xanthates are widely used in mining industry as collectors for its high affinity towards metal sulfides and precious metal ores. The possibility of using alginate for xanthation has not been explored yet despite the feasibility by the presence of hydroxyl groups alongside the polymeric chains. Therefore, this work aims to evaluate the alginate as a matrix for xanthation and its application on heavy metal ions removal. In order to obtain green materials, important pararmeter were explored such as the effect of reaction time (4-12 h), type of base (NaOH/KOH) and amount of carbon disulfide (2-10%v/v). Xanthated alginates were analyzed by NMR techniques and evidence of β-elimination was detected at 5.45 ppm. Furthermore, the presence of S element was confirmed by EDS mapping technique, while XRD showed a semi-crystalline structure. On the other hand, the chemical shifts of δ(C=S) and ν(C=S) bands were found around 863-805 cm and 662-602 cm respectively. Also, a shoulder at 182 ppm is appreciated by NMR in solid state attributed to CS group. According to FESEM analyses, morphology of xanthated alginates is affected by interaction with heavy metal ions. Finally, suitable materials for the removal of heavy metal ions were established at optimum pH values.
黄原酸盐作为金属硫化物和贵金属矿石的捕收剂，在采矿业中得到了广泛应用。尽管存在羟基基团沿聚合物链存在的可能性，但海藻酸盐用于黄原酸化的可能性尚未得到探索。因此，本工作旨在评估海藻酸盐作为黄原酸化的基质及其在重金属离子去除中的应用。为了获得绿色材料，探索了重要的参数，如反应时间（4-12 小时）、碱的类型（NaOH/KOH）和二硫化碳的用量（2-10%v/v）。通过 NMR 技术分析黄原酸海藻酸盐，并在 5.45 ppm 处检测到β-消除的证据。此外，通过 EDS 映射技术证实了 S 元素的存在，而 XRD 显示出半结晶结构。另一方面，δ（C=S）和ν（C=S）带的化学位移分别在 863-805 cm 和 662-602 cm 左右。此外，通过固态 NMR 还可以观察到 182 ppm 处的一个肩峰，归因于 CS 基团。根据 FESEM 分析，黄原酸海藻酸盐的形态受到与重金属离子相互作用的影响。最后，在最佳 pH 值下确定了适合去除重金属离子的材料。
