Adsorption Behaviors and Mechanism of Macroporous Phosphonic Acid Resin for Gadolinium

The adsorption behaviors and mechanism of a novel chelate resin, macroporous phosphonic acid resin(PAR)for Gd(Ⅲ)were investigated. The statically and dynamically saturated adsorption capacity is respectively 308 mg·g-1resin and 296 mg·g-1resin at 298 K in Hac-NaAc medium at pH 5.6. Gd(Ⅲ)adsorbed on PAR can be reductively eluted by 0.5～5.0 mol·L-1 HCl used as eluant and the elution percentage is up to 94.7% in 1.0 mol·L-1 HCl. The resin can be regenerated and reused without apparent decrease in adsorption capacity. The apparent adsorption rate constant is k298=3.96×10-5 s-1. The adsorption behavior of PAR for Gd(Ⅲ) conforms to the Freundlich isotherm. The thermodynamic adsorption parameter, enthalpy change △H of PAR for Gd(Ⅲ)is 22.6kJ·mol-1. The apparent adsorption activation energy(Ea)of PAR for Gd(Ⅲ)is 5.0 kJ·mol-1. The molar coordination ratio of the functional group of PAR to Gd(Ⅲ)is about 3∶1. The adsorption mechanism of PAR for Gd(Ⅲ)was examined by using chemical method and IR spectrometry.     

Adsorption and desorption properties of D151 resin for Ce(Ⅲ)

The present research is aimed at the development of D151 resin as an adsorbent that it can be used in the adsorption of Ce(Ⅲ) ions.The adsorption and desorption behaviors of Ce(Ⅲ) on D151 resin have been investigated by chemistry analysis.The influence of operational conditions such as contact time,initial concentration of Ce(Ⅲ),initial pH of solution and temperature on the adsorption of Ce(Ⅲ) had also been examined.The results show that the optimal adsorption condition of D151 for Ce(Ⅲ) was achieved at pH=6.50 in HAc-NaAc medium.The maximum uptake capacity of Ce(Ⅲ) was 392 mg/g resin at 298 K.The adsorption of Ce(Ⅲ) followed both the Langmuir isotherm and Freundlich isotherm,and the correlation coefficients had been evaluated.Even kinetics on the adsorption of Ce(Ⅲ) had been studied.The adsorption rate constant k298 K valued was 1.3×10-5 s-1.The calculation data of thermodynamic parameters which ΔS0 value of 91.34 and ΔH0 value of 7.07 kJ/mol indicate the endothermic nature of the adsorption process.While,a decrease of Gibb’s free energy(ΔG0) with increasing temperature indicated the spontaneous nature of the adsorption process.Finally,Ce(Ⅲ) could be eluted by using 0.5 mol/L HCl solution and the elution percentage was as high as 100%.Adsorption mechanism was also proposed for the adsorption of Ce(Ⅲ) ions onto D151 resin using infrared spectroscopy technique.     

Adsorption of erbium(Ⅲ) on D113-Ⅲ resin from aqueous solutions: batch and column studies

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...     

Adsorption behavior of gel-type weak acid resin （110-H） for Pb^2＋

The adsorption properties of a novel gel-type weak acid resin （110-H） for Pb^2＋ were investigated using chemical methods and IR spectrometry. The optimal adsorption condition of 110-H for Pb^2＋ is at pH=6.49 in HAc-NaAc medium and the statically saturated adsorption capacity is 485 mg/g at 298 K. Pb^2＋ adsorbed on 110-H resin can be eluted with 0.025 mol/L HCl quantificationally. The adsorption rate constants determined under the temperatures of 288, 298, 308 and 318 K are 2.46×10^-5, 3.82×10^-5, 4.46×10^-5 and 5.71×10^-5 s^-1, respectively. The apparent activation energy, Ea, is 18.1 kJ/mol and the thermodynamic parameters of adsorption, △H=20.9 kJ/mol, △S=-161 J/（mol·K） and △G298 K =-48.0 kJ/mol, respectively. The adsorption behavior of 110-H resin for Pb^2＋ accords with the Langmuir isotherm. Infrared spectra show that the oxygen atoms of the functional group of resin coordinate with Pb^2＋ to form the coordination bands.     

SQD-85树脂对水溶液中镱(Ⅲ)的吸附(英文)

用化学和红外光谱等方法研究SQD-85树脂对镱(III)的吸附和解吸行为,探讨溶液pH、镱(III)初始浓度、温度以及吸附时间对吸附量的影响。结果表明,SQD-85树脂在pH5.5的HAc-NaAc缓冲体系中对镱(III)的吸附效果最佳,测得树脂在308K时的静态饱和吸附量为347.6mg/g;等温吸附符合Langmuir模型;吸附动力学符合假二级动力学模型。热力学参数表明,SQD-85树脂吸附镱(III)是自发的吸热过程。动态实验结果符合Thomas模型。当用1.0mol/LHCl作解吸剂时,解吸率可达97.3%。因此,使用SQD-85树脂可以有效地去除和回收水溶液中的镱(III)。     

Enhanced adsorption behavior of Nd（Ⅲ） onto Dll3-Ⅲ resin from aqueous solution

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 equilibriumwithin 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/LHCl solution could achieve a satisfactory elution rate,which indicated that D113-III resin could be regenerated and reused.Finally,the IRspectroscopic technique was undertaken,and a novel adsorption mechanism was proposed.     

Enhanced adsorption behavior of Nd(III) onto D113-III resin from aqueous solution

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 equilibriumwithin 60 h.The resin exhibited a high Nd(III) uptake as 232.56 mg/g at 298 K.The adsorption data fitted well with p...     

Adsorption of Pb^2＋ on macroporous weak acid adsorbent resin from aqueous solutions： Batch and column studies

The adsorption properties of a novel macroporous weak acid resin (D152) for Pb²⁺ were investigated with chemical methods. The optimal adsorption condition of D152 resin for Pb²⁺ is at pH 6.00 in HAc-NaAc medium. The statically saturated adsorption capacity is 527 mg/g at 298 K. Pb²⁺ adsorbed on D152 resin can be eluted with 0.05 mol/L HCl quantitatively. The adsorption rate constants determined under various temperatures are k _{288 K}=2.22×10⁻⁵ s^t-1, k _{298 K}=2.51×10⁻⁵ s⁻¹, and k _{308 K}= 2.95×10⁻⁵ s⁻¹, respectively. The apparent activation energy, E _a is 10.5 kJ/mol, and the adsorption parameters of thermodynamics are ΔH ^Θ=13.3 kJ/mol, ΔS ^Θ=119 J/(mol·K), and ΔG ^Θ 298 K =−22.2 kJ/mol, respectively. The adsorption behavior of D152 resin for Pb²⁺ follows Langmuir model. Foundation item: Project(2008F70059) supported by the Scientific and Technological Research Planning of Zhejiang Province, China     

D113弱酸性树脂对铟(Ⅲ)的吸附性能

研究了D113弱酸性树脂在NaAc-HAc缓冲体系中对铟(III)的吸附性能及机理。对影响树脂吸附容量的不同因素,如溶液的pH、吸附时间和温度进行了研究。结果表明:D113弱酸性树脂对铟(III)的吸附在pH=5.00的NaAc-HAc缓冲体系中最佳,每克树脂在298 K下的静态饱和吸附容量为185 mg;在不同温度下,树脂吸附铟(III)的表观吸附速率常数分别为k288K=2.72×10.5 s.1,k298K=3.69×10.5 s.1,k308K=4.48×10.5 s.1,表观吸附活化能Ea=18.4 kJ.mol.1;测得热力学参数分别为.H=3.27 kJ.mol.1,.S=68.3 J.(mol.K).1,.G298K=.17.1 kJ.mol.1。与Freundlich等温曲线相比,吸附更加符合Langmuir等温曲线。用0.5 mol.L.1 HCl进行解吸时,解吸率为100%。此外,用红外光谱方法探讨了吸附机理,结果显示:D113树脂功能基COOH中的H与In(III)发生了离子交换;同时,C=O中的O与In(III)形成了配位键。     

D201×4树脂吸附钼(Ⅵ)的性能及机理

在pH=3.7的HAc-NaAc缓冲体系中,D201×4树脂对钼(Ⅵ)的静态饱和吸附容量为631mg/g.树脂,用4.0mol/LNaOH能定量解吸。测得表观吸附速率常数k298=6.25×10-5s-1。树脂吸附钼(Ⅵ)的行为遵守Freundlich方程。298K时测得吸附反应热效应ΔH=25.5kJ/mol,表观吸附活化能Ea=19.1kJ/mol。树脂功能基RN+(CH3)3Cl-与Mo(Ⅵ)的摩尔比约为1∶2。