Effects of Monodentate and Bidentate Ligands on Adsorption Characteristics of Cu-Ion-Imprinted Polymers

• Main Authors: Chou, Chia-Yin, 周佳穎
• Other Authors: Chang, Sue-min
• Format: Others
• Language: zh-TW
• Published: 2019
• Online Access: http://ndltd.ncl.edu.tw/handle/26vmw4

碩士 === 國立交通大學 === 環境工程系所 === 107 === 3-(2-aminoethylamino)propyl]trimethoxysilane (AATPS) and 3-aminopropyltriethoxysilane (APTES) were used as functional monomers to prepare Cu-imprinted-organic-inorganic polymers (IIP) while MEMO and TEOS were used as the organic and inorganic cross-linkers, respectively. Adsorption behaviors of the IIPs at different Cu(II)/amino-groups ratios were examined to investigate the complexation between the bidentate/monodentate ligands and the Cu(II) ions and the resulting imprinting extents in the IIPS. In addition, the keys controlling the selectivity of the IIPs were clarified by comparing the adsorption capacities with those for different ions. The results showed that the IIPs exhibited the highest adsorption capability at the Cu: AAPTS = 1:1 and Cu: APTES = 0.5:1 when TEOS: MEMO :H2O:ethanol were controlled at 15:10:102:200. Although the Cu/amino-groups ratios in the two systems were equal, stronger complexation between the AAPTS and the Cu(II) ions resulted in stronger adsorption sites and thus leaded the IIP-AAPTS to perform higher adsorption ability (3.0 mg/g) than APTES-based system (1.2 mg/g). Both the IIP-AAPTS and IIP-APTES had the optimal adsorption performance at pH=5 and the highest adsorption amounts were 27.55 and 17.48 mg/g, respectively. Relative to the adsorptions for Zn(II), Ni(II), Pb(II), and Hg(II) ions, the IIP-AAPTS and IIP-APTES compounds at the Cu/AAPTS=0.5-1.0 and the Cu/APTES= 0.5, respectively, showed the highest selectivity factors (k) of 89.3 and 17.5, respectively, for Cu(II) ions. The selectivity order was Cu(II)> Hg(II) > Zn(II). > Ni(II)> Pb (II), and it is controlled by ionic radii and the complex ability between the ligands and the ions. These results reveal that the bidentate AAPTS can interact with Cu(II) ions to form a more stable complex than monodentate APTES, thus is more suitable to be used as the functional monomer to prepare IIPs exhibiting high adsorption capacity and selectivity.