Department of Chemistry, Visva-Bharati University, Santiniketan 731235, India.
J Chromatogr A. 2011 Aug 19;1218(33):5644-52. doi: 10.1016/j.chroma.2011.06.083. Epub 2011 Jun 30.
A selective method has been developed for the extraction chromatographic trace level separation of Cu(II) with Versatic 10 (liquid cation exchanger) coated on silanised silica gel (SSG-V10). Cu(II) has been extracted from 0.1M acetate buffer at the range of pH 4.0-5.5. The effects of foreign ions, pH, flow-rate, stripping agents on extraction and elution have been investigated. Exchange capacity of the prepared exchanger at different temperatures with respect to Cu(II) has been determined. The extraction equilibrium constant (K(ex)) and different standard thermodynamic parameters have also been calculated by temperature variation method. Positive value of ΔH (7.98 kJ mol⁻¹) and ΔS (0.1916 kJ mol⁻¹) and negative value of ΔG (-49.16 kJ mol⁻¹) indicated that the process was endothermic, entropy gaining and spontaneous. Preconcentration factor was optimized at 74.7 ± 0.2 and the desorption constants K(desorption)¹(1.4 × 10⁻²) and K(desorption)²(9.8 × 10⁻²) were determined. The effect of pH on R(f) values in ion exchange paper chromatography has been investigated. In order to investigate the sorption isotherm, two equilibrium models, the Freundlich and Langmuir isotherms, were analyzed. Cu(II) has been separated from synthetic binary and multi-component mixtures containing various metal ions associated with it in ores and alloy samples. The method effectively permits sequential separation of Cu(II) from synthetic quaternary mixture containing its congeners Bi(III), Sn(II), Hg(II) and Cu(II), Cd(II), Pb(II) of same analytical group. The method was found effective for the selective detection, removal and recovery of Cu(II) from industrial waste and standard alloy samples following its preconcentration on the column. A plausible mechanism for the extraction of Cu(II) has been suggested.
已开发出一种选择性方法，用于用涂覆在硅烷化硅胶（SSG-V10）上的 Versatic 10（液体阳离子交换剂）对痕量 Cu(II)进行萃取色谱分离。Cu(II)已从 pH 值为 4.0-5.5 的 0.1M 乙酸盐缓冲液中提取出来。研究了外来离子、pH 值、流速、洗脱剂对萃取和洗脱的影响。在不同温度下测定了制备的交换剂对 Cu(II)的交换容量。还通过温度变化法计算了萃取平衡常数（K(ex)）和不同标准热力学参数。正的 ΔH（7.98 kJ mol⁻¹）和 ΔS（0.1916 kJ mol⁻¹）以及负的 ΔG（-49.16 kJ mol⁻¹）值表明该过程是吸热的、熵增加的和自发的。在 74.7 ± 0.2 时优化了预浓缩因子，并确定了解吸常数 K(desorption)¹(1.4 × 10⁻²)和 K(desorption)²(9.8 × 10⁻²)。研究了 pH 值对离子交换纸层析中 R(f)值的影响。为了研究吸附等温线，分析了两种平衡模型，即 Freundlich 和 Langmuir 等温线。已从矿石和合金样品中与之相关的各种金属离子的合成二元和多组分混合物中分离出 Cu(II)。该方法可有效允许从含有其同系物 Bi(III)、Sn(II)、Hg(II)和 Cu(II)的合成四元混合物中连续分离 Cu(II)，以及 Cd(II)、Pb(II)同属组。该方法在其预浓缩后，被发现可有效用于从工业废物和标准合金样品中选择性检测、去除和回收 Cu(II)。提出了一种提取 Cu(II)的合理机制。
