Iannazzo Daniela, Pistone Alessandro, Ziccarelli Ida, Espro Claudia, Galvagno Signorino, Giofré Salvatore V, Romeo Roberto, Cicero Nicola, Bua Giuseppe D, Lanza Giuseppe, Legnani Laura, Chiacchio Maria A
Dipartimento di Ingegneria, University of Messina, Contrada Di Dio, 98166, Messina, Italy.
Dipartimento di Scienze chimiche, biologiche, farmaceutiche ed ambientali, University of Messina, Viale Annunziata, 98168, Messina, Italy.
Environ Sci Pollut Res Int. 2017 Jun;24(17):14735-14747. doi: 10.1007/s11356-017-9086-2. Epub 2017 May 3.
Dendrimer-functionalized multi-walled carbon nanotubes (MWCNT) for heavy metal ion removal from wastewaters were developed. Triazole dendrimers (TD) were built directly onto the carbon nanotube surface by successive click chemistry reactions affording the zero- and first-generation dendrimer-functionalized MWCNT (MWCNT-TD1 and MWCNT-TD2). The Moedritzer-Irani reaction carried out on the amino groups present on the MWCNT-TD2 sample gave the corresponding α-aminophosphonate nanosystem MWCNT-TD2P. Both MWCNT-TD2 and MWCNT-TD2P nanosystems have been characterized by physical, chemical, and morphological analyses. Their chelating abilities towards the toxic metal ions Pb, Hg, and Ni and the harmless Ca ion have been experimentally evaluated in the two different sets of experiments and at the salt concentrations of 1 mg/mL or 1 μg/mL by inductively coupled plasma mass spectrometry (ICP-MS). The results of these studies pointed out the interesting chelating behavior for the phosphonated nanosystem towards the Hg ion. The complexation mode of the best chelating system MWCNT-TD2P with mercury was investigated through density functional theory (DFT) calculations, suggesting a chelation mechanism involving the two oxygen atoms of the phosphate group. The synthesized dendrimers, supported on the multi-walled carbon nanotubes, have shown the potential to be used for the selective toxic metal ion removal and recovery.
开发了用于从废水中去除重金属离子的树枝状大分子功能化多壁碳纳米管（MWCNT）。通过连续的点击化学反应将三唑树枝状大分子（TD）直接构建在碳纳米管表面，得到零代和第一代树枝状大分子功能化的MWCNT（MWCNT-TD1和MWCNT-TD2）。对MWCNT-TD2样品上存在的氨基进行Moedritzer-Irani反应，得到相应的α-氨基膦酸纳米体系MWCNT-TD2P。MWCNT-TD2和MWCNT-TD2P纳米体系均已通过物理、化学和形态分析进行了表征。通过电感耦合等离子体质谱（ICP-MS）在两组不同的实验中以及在1 mg/mL或1 μg/mL的盐浓度下，对它们对有毒金属离子Pb、Hg和Ni以及无害Ca离子的螯合能力进行了实验评估。这些研究结果指出了膦酸化纳米体系对Hg离子有趣的螯合行为。通过密度泛函理论（DFT）计算研究了最佳螯合体系MWCNT-TD2P与汞的络合模式，表明存在一种涉及磷酸基团两个氧原子的螯合机制。负载在多壁碳纳米管上的合成树枝状大分子已显示出用于选择性去除和回收有毒金属离子的潜力。
