A two-stage ligand selection method composed of a primary selection and a critical selection,for complex-leaching valuable metals was presented.At the primary selection stage,three conditions were discussed under a su...A two-stage ligand selection method composed of a primary selection and a critical selection,for complex-leaching valuable metals was presented.At the primary selection stage,three conditions were discussed under a supposed ideal state by mathematical derivation.Generally,ligands selected under condition Ⅰwere easier for complex-leaching valuable metals than that under conditionⅡ,however,under conditionⅢ,ligands selected were hard to complex-leaching the valuable metals.Ligands that were out of these three conditions could be disposed directly.In critical selection,ligands selected in primary selection can be finalized.Case applications were provided for verifying the method.The application indicated that iminodiacetate(Ida2-)can be used as a complex agent for complex-leaching smithsonite(ZnCO3);the leaching condition should be controlled with pH 8-11;the relative error of the minimum consumption of Ida2-between the predicted and the calculated results is 5.3%.The results indicate that the theoretical derivations in the ideal state are reliable,and the method for ligand selection is practical and operable.展开更多
The removal of copper ions from wastewater by ion exchange has been studied using an iminodiacetate resin.The capacity of the resin for the copper ions has been determined to be 2.30 mmol·g^(-1) by measuring the ...The removal of copper ions from wastewater by ion exchange has been studied using an iminodiacetate resin.The capacity of the resin for the copper ions has been determined to be 2.30 mmol·g^(-1) by measuring the equilibrium isotherm at 25 °C and initial pH value of 3.5 where the final equilibrium p H value is 5. An analysis of equilibrium isotherm models showed that the best fit model was the Langmuir–Freundlich. The kinetics of the ion exchange process have been investigated and four kinetic models have been tested namely: Ritchie model, pseudo-second order model, pseudo-first order model and the Elovich model. The pseudo-second order model provides the best fit to the kinetic data.展开更多
The sorption behavior and mechanism of a novel chelate resin, diglycolamidic acid resin (DAAR), for Sm(III) were investigated. The optimal sorption condition of DAAR for Sm(III) is pH=6.0 in HAc-NaAc medium. The stati...The sorption behavior and mechanism of a novel chelate resin, diglycolamidic acid resin (DAAR), for Sm(III) were investigated. The optimal sorption condition of DAAR for Sm(III) is pH=6.0 in HAc-NaAc medium. The statically saturated sorption capacity is 190mg/g resin at 298K. The Sm(III) adsorbed on DAAR can be eluted reaching 100% by 0.5~2.0mol/L HCl used as eluant. The resin can be regenerated and reused without apparent decrease of sorption capacity. The apparent sorption rate constant is k298= 1.96×10-5s-1. The apparent activation energy is 26kJ/mol. The sorption behavior of DAAR for Sm(III) obeys the Freundlich isotherm. The thermodynamic sorption parameters, enthalpy change 腍 of DAAR for Sm(III) is 16.9kJ/mol. The molar coordination ratio of the functional group of DAAR to Sm (III) is 3. The sorption mechanism of DAAR for Sm(III) was examined by using chemical method and IR spectrometry. The coordination bond was formed between oxygen atoms in the functional group of DAAR and Sm(III).展开更多
Here, the employment of subcritical water as an environmentally benign media has shown a certain potential for the hydrolysis ofiminodiaeetonitrile （IDAN）. Additives （such as NH3.H2O, （NH4）2CO3, K2CO3） were sele...Here, the employment of subcritical water as an environmentally benign media has shown a certain potential for the hydrolysis ofiminodiaeetonitrile （IDAN）. Additives （such as NH3.H2O, （NH4）2CO3, K2CO3） were selected to investigate the reactivity ofiminodiacetonitrile in the solutions of these species in the subcritical region for the possibility of preparing iminodiacetic acid （IDA） salts. A series of reactions were performed in a high temperature and pressure batch reactor with temperature ranging from 200 to 260 ℃, time ranging from 4 to 10 min, pressure ranging from 5 to 25 MPa and varying concentration of additives to consider the influence of these parameters on the yield of IDA salts. Reactivity of IDAN was not illustrated with the conversion but with respect to the yield of resultant IDA salts. The results demonstrate that hydrolysis reactivity of IDAN under the examined conditions has shown a remarkable sensitivity to the pH of the system at initial point of the reaction stage, and temperature effect is also obvious. Based on the results, possible reaction pathway and mechanism were proposed.展开更多
Iminodiacetic acid functionalized polyglycidyl methacrylate grafted-carbon fibers(PGMA-IDA/CFs) were prepared for Ni(II) removal from aqueous solutions. The effects of solution p H value, temperature and adsorption ti...Iminodiacetic acid functionalized polyglycidyl methacrylate grafted-carbon fibers(PGMA-IDA/CFs) were prepared for Ni(II) removal from aqueous solutions. The effects of solution p H value, temperature and adsorption time were investigated. The maximum adsorption capacity of Ni(II) on PGMA-IDA/CFs is 0.923 mmol·L-1· g-1at pH 5.2 and 50 °C. Kinetic data indicate that the adsorption process matches the pseudo-second-order model and Elovich kinetic model. Thermodynamic data suggest that the adsorption process is endothermic spontaneous reaction.展开更多
Reported here is a water-soluble ligand, N-（sulfoethyl）-iminodiacetic acid （H3SEIDA）, used for the complexation of uranyl ions. A coordination compound composed of uranyl cation and N-（sulfonatoethyl）-ammoniodia...Reported here is a water-soluble ligand, N-（sulfoethyl）-iminodiacetic acid （H3SEIDA）, used for the complexation of uranyl ions. A coordination compound composed of uranyl cation and N-（sulfonatoethyl）-ammoniodiacetate （SEADA2-） zwitterion was synthesized from an acidic aqueous solution. This compound features a 2D undulating fes （4.82） coordination layer that is stacked and linked by hydrogen-bonding interaction to form a 3D supramolecular framework with a 1D larger-cycle channel. Thermal analysis demonstrates the relatively weak bonding between uranyl cation and SEADA2 zwitterion. The monomeric uranyl-based fluorescence emission is red-shifted by about thermal synthesis of this uranyl compound was successfully 5 nm compared to that of uranyl nitrate hexahydrate. The hydro- applied to the sequestration of uranyl ions.展开更多
基金Project(2007CB613604) supported by the National Basic Research Program of China
文摘A two-stage ligand selection method composed of a primary selection and a critical selection,for complex-leaching valuable metals was presented.At the primary selection stage,three conditions were discussed under a supposed ideal state by mathematical derivation.Generally,ligands selected under condition Ⅰwere easier for complex-leaching valuable metals than that under conditionⅡ,however,under conditionⅢ,ligands selected were hard to complex-leaching the valuable metals.Ligands that were out of these three conditions could be disposed directly.In critical selection,ligands selected in primary selection can be finalized.Case applications were provided for verifying the method.The application indicated that iminodiacetate(Ida2-)can be used as a complex agent for complex-leaching smithsonite(ZnCO3);the leaching condition should be controlled with pH 8-11;the relative error of the minimum consumption of Ida2-between the predicted and the calculated results is 5.3%.The results indicate that the theoretical derivations in the ideal state are reliable,and the method for ligand selection is practical and operable.
文摘The removal of copper ions from wastewater by ion exchange has been studied using an iminodiacetate resin.The capacity of the resin for the copper ions has been determined to be 2.30 mmol·g^(-1) by measuring the equilibrium isotherm at 25 °C and initial pH value of 3.5 where the final equilibrium p H value is 5. An analysis of equilibrium isotherm models showed that the best fit model was the Langmuir–Freundlich. The kinetics of the ion exchange process have been investigated and four kinetic models have been tested namely: Ritchie model, pseudo-second order model, pseudo-first order model and the Elovich model. The pseudo-second order model provides the best fit to the kinetic data.
基金The Natural Science Foundation of Zhejiang Province (No.200072)
文摘The sorption behavior and mechanism of a novel chelate resin, diglycolamidic acid resin (DAAR), for Sm(III) were investigated. The optimal sorption condition of DAAR for Sm(III) is pH=6.0 in HAc-NaAc medium. The statically saturated sorption capacity is 190mg/g resin at 298K. The Sm(III) adsorbed on DAAR can be eluted reaching 100% by 0.5~2.0mol/L HCl used as eluant. The resin can be regenerated and reused without apparent decrease of sorption capacity. The apparent sorption rate constant is k298= 1.96×10-5s-1. The apparent activation energy is 26kJ/mol. The sorption behavior of DAAR for Sm(III) obeys the Freundlich isotherm. The thermodynamic sorption parameters, enthalpy change 腍 of DAAR for Sm(III) is 16.9kJ/mol. The molar coordination ratio of the functional group of DAAR to Sm (III) is 3. The sorption mechanism of DAAR for Sm(III) was examined by using chemical method and IR spectrometry. The coordination bond was formed between oxygen atoms in the functional group of DAAR and Sm(III).
文摘Here, the employment of subcritical water as an environmentally benign media has shown a certain potential for the hydrolysis ofiminodiaeetonitrile （IDAN）. Additives （such as NH3.H2O, （NH4）2CO3, K2CO3） were selected to investigate the reactivity ofiminodiacetonitrile in the solutions of these species in the subcritical region for the possibility of preparing iminodiacetic acid （IDA） salts. A series of reactions were performed in a high temperature and pressure batch reactor with temperature ranging from 200 to 260 ℃, time ranging from 4 to 10 min, pressure ranging from 5 to 25 MPa and varying concentration of additives to consider the influence of these parameters on the yield of IDA salts. Reactivity of IDAN was not illustrated with the conversion but with respect to the yield of resultant IDA salts. The results demonstrate that hydrolysis reactivity of IDAN under the examined conditions has shown a remarkable sensitivity to the pH of the system at initial point of the reaction stage, and temperature effect is also obvious. Based on the results, possible reaction pathway and mechanism were proposed.
基金Supported by the National Natural Science Foundation of China(21076054 and U140710231)the Natural Science Important Foundation of Educational Commission of Anhui Province(2010AJZR-85,2011AJZR-87)+1 种基金Study Foundation of New Product and Technology of Anhui Economic and Information Technology Commission(2012AHST0797,2013CXSY327 and 2013CXSY366)National College Student Innovation Fund(2014CXCY321 and 2014CXCY349)
文摘Iminodiacetic acid functionalized polyglycidyl methacrylate grafted-carbon fibers(PGMA-IDA/CFs) were prepared for Ni(II) removal from aqueous solutions. The effects of solution p H value, temperature and adsorption time were investigated. The maximum adsorption capacity of Ni(II) on PGMA-IDA/CFs is 0.923 mmol·L-1· g-1at pH 5.2 and 50 °C. Kinetic data indicate that the adsorption process matches the pseudo-second-order model and Elovich kinetic model. Thermodynamic data suggest that the adsorption process is endothermic spontaneous reaction.
基金financially supported by the National Natural Science Foundation of China(91122007)the Specialized Research Fund for the Doctoral Program of Higher Education(20110211130002)
文摘Reported here is a water-soluble ligand, N-（sulfoethyl）-iminodiacetic acid （H3SEIDA）, used for the complexation of uranyl ions. A coordination compound composed of uranyl cation and N-（sulfonatoethyl）-ammoniodiacetate （SEADA2-） zwitterion was synthesized from an acidic aqueous solution. This compound features a 2D undulating fes （4.82） coordination layer that is stacked and linked by hydrogen-bonding interaction to form a 3D supramolecular framework with a 1D larger-cycle channel. Thermal analysis demonstrates the relatively weak bonding between uranyl cation and SEADA2 zwitterion. The monomeric uranyl-based fluorescence emission is red-shifted by about thermal synthesis of this uranyl compound was successfully 5 nm compared to that of uranyl nitrate hexahydrate. The hydro- applied to the sequestration of uranyl ions.
