The sorption behavior and mechanism of a novel macroporous weak acid resin(D113 resin) for Er(Ⅲ) were investigated. The optimal sorption condition of D113 resin for Er(Ⅲ) was pH 6.42 in HAc-NaAc medium. The statical...The sorption behavior and mechanism of a novel macroporous weak acid resin(D113 resin) for Er(Ⅲ) were investigated. The optimal sorption condition of D113 resin for Er(Ⅲ) was pH 6.42 in HAc-NaAc medium. The statically saturated sorption capacity was 272 mg·g-1 at 298 K in HAc-NaAc medium. The Er(Ⅲ) adsorbed on D113 resin could be reductively eluted by the mixed solution of HCl and NaCl. The elution percentage could reach 100%. The resin could be regenerated and reused without apparent decrease of sorption capacity. The apparent sorption rate constant was k298=1.98×10-5 s-1. The apparent activation energy was 8.60 kJ·mol-1. The sorption behavior of D113 resin for Er(Ⅲ) obeyed the Freundlich isotherm and Langmuir isotherm. The sorption parameters of thermodynamics were ΔH=44.0 kJ·mol-1, ΔS=223 J·mol-1·K-1, ΔG298 K=-22.3 kJ·mol-1, respectively. The molar coordination ratio of the functional group of D113 resin to Er(Ⅲ) was 3∶1. The sorption mechanism of D113 resin for Er(Ⅲ) was examined using chemical method and IR spectrometry.展开更多
The adsorption and desorption behaviors of Er(Ⅲ) ion on D113-Ⅲ resin were investigated.Batch adsorption studies were carried out with various Er(Ⅲ) ion concentrations,pH,contact time and temperature,indicating that...The adsorption and desorption behaviors of Er(Ⅲ) ion on D113-Ⅲ resin were investigated.Batch adsorption studies were carried out with various Er(Ⅲ) ion concentrations,pH,contact time and temperature,indicating that D113-Ⅲ resin could adsorb Er(Ⅲ) ion effectively from aqueous solution.The loading of Er(Ⅲ) ion onto D113-Ⅲ resin increased with increasing the initial concentration.The adsorption was strongly dependent on pH of the medium with enhanced adsorption as the pH turned from 3.45 to 6.75.In the batch s...展开更多
Batch adsorption experiments were conducted for the adsorption of Eu(Ⅲ) ions from aqueous solution by D113 resin. The results indicated that D113 resin could adsorb Eu(Ⅲ) ion effectively from aqueous solution. The a...Batch adsorption experiments were conducted for the adsorption of Eu(Ⅲ) ions from aqueous solution by D113 resin. The results indicated that D113 resin could adsorb Eu(Ⅲ) ion effectively from aqueous solution. The adsorption was strongly dependent on pH of the medium with enhanced adsorption as the pH turned from 3.50 to 7.00 and the optimal adsorption condition was in HAc-NaAc medium with pH value of 6.50. The maximum uptake capacity of Eu(Ⅲ) ions was 290.9 mg/g D113 at 298 K, at an initial pH value of 6.50. The overall adsorption process was best described by Lagergren-first-order kinetics. When Freundlich and Langmuir isotherms were tested, the latter had a better fit with the experimental data. The thermodynamic parameters such as free energy (G) which were all negative, indicated that the adsorption of Eu(Ⅲ) ions onto D113 resin was spontaneous and the positive value of enthalpy (H) showed that the adsorption was endothermic in nature. Thomas model was applied to experimental column data to determine the characteristic parameters of column useful for process design. Furthermore, Eu(Ⅲ) could be eluted by using 3.0 mol/L HCl solution and the D113 resin could be regenerated and reused.展开更多
An enhanced adsorption and desorption procedure of Nd（Ⅲ） onto D113-Ⅲ resin were prepared with various chemical methods. Batch studies were carried out with various pH, contact time, temperature and initial concent...An enhanced adsorption and desorption procedure of Nd（Ⅲ） onto D113-Ⅲ resin were prepared with various chemical methods. Batch studies were carried out with various pH, contact time, temperature and initial concentrations, and then column studies were conducted. The results showed that the optimal adsorption condition was at pH value of 6.90. The process was fast initially and arrived equilibrium within 60 h. The resin exhibited a high Nd（Ⅲ） uptake as 232.56 mg/g at 298 K. The adsorption data fitted well with pseudo-second-order kinetic model. Thermodynamic parameters were studied, which indicated that the adsorption process was spontaneous and endothermic. Thomas model was delineated here to predict the breakthrough curves based on the experimental column study data. In the elution test, 1 mol/L HCl solution could achieve a satisfactory elution rate, which indicated that D113-1/1 resin could be regenerated and reused. Finally, the IR spectroscopic technique was undertaken, and a novel adsorption mechanism was proposed.展开更多
基金the Zhejiang Provincial Natural Science Foundation of China (Y404279)
文摘The sorption behavior and mechanism of a novel macroporous weak acid resin(D113 resin) for Er(Ⅲ) were investigated. The optimal sorption condition of D113 resin for Er(Ⅲ) was pH 6.42 in HAc-NaAc medium. The statically saturated sorption capacity was 272 mg·g-1 at 298 K in HAc-NaAc medium. The Er(Ⅲ) adsorbed on D113 resin could be reductively eluted by the mixed solution of HCl and NaCl. The elution percentage could reach 100%. The resin could be regenerated and reused without apparent decrease of sorption capacity. The apparent sorption rate constant was k298=1.98×10-5 s-1. The apparent activation energy was 8.60 kJ·mol-1. The sorption behavior of D113 resin for Er(Ⅲ) obeyed the Freundlich isotherm and Langmuir isotherm. The sorption parameters of thermodynamics were ΔH=44.0 kJ·mol-1, ΔS=223 J·mol-1·K-1, ΔG298 K=-22.3 kJ·mol-1, respectively. The molar coordination ratio of the functional group of D113 resin to Er(Ⅲ) was 3∶1. The sorption mechanism of D113 resin for Er(Ⅲ) was examined using chemical method and IR spectrometry.
基金supported by the Analysis Project under Zhejiang Provincial Scientific and Technological Research Planning (2008F70059)Zhejiang University Graduate Business Research Innovation Fund
文摘The adsorption and desorption behaviors of Er(Ⅲ) ion on D113-Ⅲ resin were investigated.Batch adsorption studies were carried out with various Er(Ⅲ) ion concentrations,pH,contact time and temperature,indicating that D113-Ⅲ resin could adsorb Er(Ⅲ) ion effectively from aqueous solution.The loading of Er(Ⅲ) ion onto D113-Ⅲ resin increased with increasing the initial concentration.The adsorption was strongly dependent on pH of the medium with enhanced adsorption as the pH turned from 3.45 to 6.75.In the batch s...
基金Project supported by the Key (Key grant) Project of Education Department of Zhejiang Province (Z200907459)
文摘Batch adsorption experiments were conducted for the adsorption of Eu(Ⅲ) ions from aqueous solution by D113 resin. The results indicated that D113 resin could adsorb Eu(Ⅲ) ion effectively from aqueous solution. The adsorption was strongly dependent on pH of the medium with enhanced adsorption as the pH turned from 3.50 to 7.00 and the optimal adsorption condition was in HAc-NaAc medium with pH value of 6.50. The maximum uptake capacity of Eu(Ⅲ) ions was 290.9 mg/g D113 at 298 K, at an initial pH value of 6.50. The overall adsorption process was best described by Lagergren-first-order kinetics. When Freundlich and Langmuir isotherms were tested, the latter had a better fit with the experimental data. The thermodynamic parameters such as free energy (G) which were all negative, indicated that the adsorption of Eu(Ⅲ) ions onto D113 resin was spontaneous and the positive value of enthalpy (H) showed that the adsorption was endothermic in nature. Thomas model was applied to experimental column data to determine the characteristic parameters of column useful for process design. Furthermore, Eu(Ⅲ) could be eluted by using 3.0 mol/L HCl solution and the D113 resin could be regenerated and reused.
基金supported by the National Natural Science Foundation of China(20972138)the Key Grant of Education Department of Zhejiang Province,China(Z200907459)
文摘An enhanced adsorption and desorption procedure of Nd（Ⅲ） onto D113-Ⅲ resin were prepared with various chemical methods. Batch studies were carried out with various pH, contact time, temperature and initial concentrations, and then column studies were conducted. The results showed that the optimal adsorption condition was at pH value of 6.90. The process was fast initially and arrived equilibrium within 60 h. The resin exhibited a high Nd（Ⅲ） uptake as 232.56 mg/g at 298 K. The adsorption data fitted well with pseudo-second-order kinetic model. Thermodynamic parameters were studied, which indicated that the adsorption process was spontaneous and endothermic. Thomas model was delineated here to predict the breakthrough curves based on the experimental column study data. In the elution test, 1 mol/L HCl solution could achieve a satisfactory elution rate, which indicated that D113-1/1 resin could be regenerated and reused. Finally, the IR spectroscopic technique was undertaken, and a novel adsorption mechanism was proposed.
