The conditions relating to enhanced adsorption procedure of earth element europium（Eu） onto gel-type weak acid resin（110-H） in aqueous solution were optimized by means of the response surface methodology（RSM）, w...The conditions relating to enhanced adsorption procedure of earth element europium（Eu） onto gel-type weak acid resin（110-H） in aqueous solution were optimized by means of the response surface methodology（RSM）, which proved that 110-H owned satisfactory adsorption capacity（346.85 mg/g） in optimum conditions, belonging to one of the high adsorption capacity materials. Then, the adsorption and desorption behaviors were investigated by batch studies. The adsorption performance showed high agreement with the Lagergren-first-order model and Langmuir isotherm with thermodynamic adsorption parameters of ΔH= 36.1 k J/mol and ΔS=200 J/（mol·K）. Desorption study revealed that 110-H could be effectively eluted by a low concentration of HCl solution（0.1 mol/L） to regenerate and reuse. Finally, the 110-H and Eu（III） loaded 110-H were characterized by IR spectroscopy and scanning electron microscope（SEM） to analyze the mechanism of adsorption, which proved to be chemisorbed.展开更多
Uptakes of pyruvic acid for two types of commercially available weakly basic polymer sorbents, D301G and D301R, have been measured over a wide pH range and at various salinities of MgSO4. The results show that the ove...Uptakes of pyruvic acid for two types of commercially available weakly basic polymer sorbents, D301G and D301R, have been measured over a wide pH range and at various salinities of MgSO4. The results show that the overloading adsorption of pyruvic acid occurs on both weakly basic polymer sorbents, and the overloading models can predict the experimental data of uptake very well. The overloading value for D301G is larger than that for D301R. The adsorption isotherm of pyruvic acid for both polymeric sorbents is greatly affected by the solution pH and MgSO4 concentration in the aqueous phase, and a high recovery efficiency of pyruvic acid from aqueous solution can be obtained at the solution pH around 2.展开更多
This research deals with an investigation of the adsorption of two acids, namely, 5-amino- 2-chlorotoluene-4-sulfonic and chlorhydric acids from their solution onto weakly basic resin. The screening of res-ins, kineti...This research deals with an investigation of the adsorption of two acids, namely, 5-amino- 2-chlorotoluene-4-sulfonic and chlorhydric acids from their solution onto weakly basic resin. The screening of res-ins, kinetics, and isotherm were studied. The results indicate that the D301R is more appropriate for the removal of acids from solution. The adsorption of acids obeys Langmuir isotherm and the first-order kinetics model. Sorptive affinity of the two acids on D301R was found to be in the order of 5-amino-2-chlorotoluene-4-sulfonic acid> chlorhydric acid. Thermodynamic parameters for the adsorption of acids were calculated and discussed. The maxi-mum removal of acids was observed around 97% and 76% at 25℃ for 5-amino-2-chlorotoluene-4-sulfonic acid and chlorhydric acid , respectively.展开更多
Experiments for single and bisolute competitive adsorption were carried out to investigate the adsorption behavior of β-naphthalenesulfonic acid(NSA) and sulfuric acid (H_2SO_4) from their solution at 25℃ onto weakl...Experiments for single and bisolute competitive adsorption were carried out to investigate the adsorption behavior of β-naphthalenesulfonic acid(NSA) and sulfuric acid (H_2SO_4) from their solution at 25℃ onto weakly basic resin D301R. Adsorption affinity of sulfuric acid on D301R was found to be much higher than that of NSA. The data of single-solute adsorption were fitted to the Langmuir model and the Freundlich adsorption model. The ideal adsorbed solution theory(IAST) coupled with the single-solute adsorption models were used to predict the bisolute competitive adsorption equilibria. The IAST coupled with the Langmuir and the Freundlich model for sulfuric acid and NSA, respectively, yields the favorable representation of the bisolute competitive adsorption behavior.展开更多
Experiments for single and bisolute competitive adsorption were carried out to investigate the adsorption behavior of /3-naphthalenesulfonic acid (NSA) and sulfuric acid from their solution at 25C onto weakly basic re...Experiments for single and bisolute competitive adsorption were carried out to investigate the adsorption behavior of /3-naphthalenesulfonic acid (NSA) and sulfuric acid from their solution at 25C onto weakly basic resin D301R. Adsorption affinity of sulfuric acid on D301R was found to be much higher than that of NSA. The data of single-solute adsorption were fitted to the Langmuir model and the Preundlich adsorption model. The ideal adsorbed solution theory (IAST) coupled with the single-solute adsorption models were used to predict the bisolute competitive adsorption equilibria. The IAST coupled with the Langmuir and the Freundlich model for sulfuric acid and NSA, respectively, yields the favorable representation of the bisolute competitive adsorption behavior.展开更多
The adsorption properties of a novel macroporous weak acid resin （D152） for Pb^2＋ were investigated with chemical methods. The optimal adsorption condition of D152 resin for Pb^2＋ is at pH 6.00 in HAc-NaAc medium....The adsorption properties of a novel macroporous weak acid resin （D152） for Pb^2＋ were investigated with chemical methods. The optimal adsorption condition of D152 resin for Pb^2＋ is at pH 6.00 in HAc-NaAc medium. The statically saturated adsorption capacity is 527 mg/g at 298 K. Pb^2＋ adsorbed on D152 resin can be eluted with 0.05 mol/L HCI quantitatively. The adsorption rate constants determined under various temperatures are k288 n=2.22×10-5 s^-1, k298 K=2.51 × 10^-5 s^-1, and k308 K= 2.95 × 10^-5 s^-1, respectively. The apparent activation energy, Ea 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^Θ298 K =-22.2 kJ/mol, respectively. The adsorption behavior of D152 resin for Pb^2＋ follows Langmuir model.展开更多
The adsorption equilibrium isotherms of three aromatic sulfonic acid compounds, 2-naphthalenesulfonic acid, p-toluenesulfonic acid and p-chlorobenzenesulfonic acid, from aqueous solutions by macroporous weak base anio...The adsorption equilibrium isotherms of three aromatic sulfonic acid compounds, 2-naphthalenesulfonic acid, p-toluenesulfonic acid and p-chlorobenzenesulfonic acid, from aqueous solutions by macroporous weak base anion exchanger within the temperature range of 293 K-313 K were obtained. Several isotherm equations were correlated with the equilibrium data, and the experimental data was found to fit the three-parameter Redlich-Peterson equation best within the entire range of concentrations. The study showed that the hydrophobicity of solute has distinct influence on adsorption capacity of the anion exchanger for the aromatic sulfonic acid. Moreover, estimations of the isosteric enthalpy, free energy, and entropy change of adsorption were also reported. The positive isosteric enthalpy and entropy change for adsorption indicate an endothermic and entropy driven process in the present study.展开更多
Fluid coking on micro-spherical particles with acid sites on them could produce more light oils from Tahe AR.The conversion rate could increase by about 20% on the catalyst B compared to that obtained on the catalyst ...Fluid coking on micro-spherical particles with acid sites on them could produce more light oils from Tahe AR.The conversion rate could increase by about 20% on the catalyst B compared to that obtained on the catalyst A and the light oil yield could increase by about 12%.The yield of gasoline and diesel was more than 50% from Tahe AR over the catalyst B.Tests on acidity of the catalyst B by pyridine FT-IR spectrometry showed that the total acid content and the ratio of weak acid number to total acid number were higher than other catalysts.展开更多
The adsorption properties of a novel gel-type weak acid resin (110-H) for Pb2+ were investigated using chemical methods and IR spectrometry.The optimal adsorption condition of 110-H for Pb2+ is at pH=6.49 in HAc-NaAc ...The adsorption properties of a novel gel-type weak acid resin (110-H) for Pb2+ were investigated using chemical methods and IR spectrometry.The optimal adsorption condition of 110-H for Pb2+ is at pH=6.49 in HAc-NaAc medium and the statically saturated adsorption capacity is 485 mg/g at 298 K.Pb2+ 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,ΔH=20.9 kJ/mol,ΔS=161 J/(mol.K) and ΔG298 K =-48.0 kJ/mol,respectively.The adsorption behavior of 110-H resin for Pb2+ accords with the Langmuir isotherm.Infrared spectra show that the oxygen atoms of the functional group of resin coordinate with Pb2+ to form the coordination bands.展开更多
Objective To study the adsorption of 5-Amino-2-chlorotoluene-4-sulfonic (CLT) and chlorhydric (HCl) acids from wastewater by weakly basic resin. Methods The kinetics and isotherm were studied. Thermodynamic parameters...Objective To study the adsorption of 5-Amino-2-chlorotoluene-4-sulfonic (CLT) and chlorhydric (HCl) acids from wastewater by weakly basic resin. Methods The kinetics and isotherm were studied. Thermodynamic parameters for the adsorption of acids were calculated and discussed. Results The adsorption of CLT and HCl acids followed Langmuir isotherm and the first-order kinetics model. Conclusion The adsorptive affinity of the two acids on D301R is in the order of CLT acid 〉 HCl acid. CLT and HCl acids can be separated.展开更多
pH-fixed titration method for the determination of weak acids and bases has been studied in this paper.It is not necessary to know the ionization constant of weak acid or base and the concentration of titrant. This me...pH-fixed titration method for the determination of weak acids and bases has been studied in this paper.It is not necessary to know the ionization constant of weak acid or base and the concentration of titrant. This method had been applied to determine phenol,4-aminoantipyrine and glycine,whose ionization constants range from 10^(-10)to 10^(-12).The results were satisfactory.展开更多
The “overlapping equilibria” effect observed in the processes of electrolytic dissociation of many weak multibasic organic acids determines the character of these processes. In this communication, the degree of “ov...The “overlapping equilibria” effect observed in the processes of electrolytic dissociation of many weak multibasic organic acids determines the character of these processes. In this communication, the degree of “overlapping equilibria” in case of weak dibasic organic acids is quantitatively characterized by the values of “partial” degree of dissociation for second step and ratio of the concentrations of dianion and monoanion. It has been shown that these dissociation parameters are directly connected with the values of the second dissociation constant. It has been also shown that the contribution of third dissociation step in the “overlapping equilibria” effect is especially appreciable in case of penta and hexabasic weak organic acids causing the double “overlapping” phenomenon.展开更多
A new method for the determination of ionization constants of polyprotic weak acids is presented. Based on dissociation equilibrium,mass balance and charge balance, the mathematic model is established and the non line...A new method for the determination of ionization constants of polyprotic weak acids is presented. Based on dissociation equilibrium,mass balance and charge balance, the mathematic model is established and the non linear least squares Gauss Newton method is applied to numerically solve the model equations. In order to get the concentration of hydrogen ion, the Debye Hückel equation is used to calculate its activity coefficient. The ionization constants of H 2SO 3 and H 2C 2O 4 obtained by this method are in good agreement with the literature values.展开更多
This paper reports a new method of titration for very weak acids and bases using the appearance of incisions on oscillopolarogram to indicate the end-point.This method has the advantages of rapidity,simplicity,no indi...This paper reports a new method of titration for very weak acids and bases using the appearance of incisions on oscillopolarogram to indicate the end-point.This method has the advantages of rapidity,simplicity,no indicator needed as well as good precision.展开更多
模拟投料环境,探索温度、时间、氧化剂NaClO、弱碱NaHCO_(3)、弱酸NaHSO_(3)对DTD分解情况的影响。结果表明:温度低于15℃时DTD分解缓慢,高于15℃时DTD分解迅速,且随时间的延长分解加剧。氧化剂NaClO会造成产物的迅速分解,4 h DTD分解剩...模拟投料环境,探索温度、时间、氧化剂NaClO、弱碱NaHCO_(3)、弱酸NaHSO_(3)对DTD分解情况的影响。结果表明:温度低于15℃时DTD分解缓慢,高于15℃时DTD分解迅速,且随时间的延长分解加剧。氧化剂NaClO会造成产物的迅速分解,4 h DTD分解剩余24.53%。NaHCO_(3)、NaHSO_(3)的加入对DTD的分解影响较小。为避免长时间对收率的影响,合成结束后需迅速进行后处理,对后期工业化生产具有重要的指导意义。展开更多
基金Project(20133326110006)supported by Ph D Programs Foundation of Ministry of Education of ChinaProject(2014R408073)supported by College Student Innovation Projects of Zhejiang Province+2 种基金ChinaProject supported by Zhejiang Provincial Key Laboratory of Industrial Textile Materials&Manufacturing TechChina
文摘The conditions relating to enhanced adsorption procedure of earth element europium（Eu） onto gel-type weak acid resin（110-H） in aqueous solution were optimized by means of the response surface methodology（RSM）, which proved that 110-H owned satisfactory adsorption capacity（346.85 mg/g） in optimum conditions, belonging to one of the high adsorption capacity materials. Then, the adsorption and desorption behaviors were investigated by batch studies. The adsorption performance showed high agreement with the Lagergren-first-order model and Langmuir isotherm with thermodynamic adsorption parameters of ΔH= 36.1 k J/mol and ΔS=200 J/（mol·K）. Desorption study revealed that 110-H could be effectively eluted by a low concentration of HCl solution（0.1 mol/L） to regenerate and reuse. Finally, the 110-H and Eu（III） loaded 110-H were characterized by IR spectroscopy and scanning electron microscope（SEM） to analyze the mechanism of adsorption, which proved to be chemisorbed.
基金Supported by the National Natural Science Foundation of China （No.29836130）.
文摘Uptakes of pyruvic acid for two types of commercially available weakly basic polymer sorbents, D301G and D301R, have been measured over a wide pH range and at various salinities of MgSO4. The results show that the overloading adsorption of pyruvic acid occurs on both weakly basic polymer sorbents, and the overloading models can predict the experimental data of uptake very well. The overloading value for D301G is larger than that for D301R. The adsorption isotherm of pyruvic acid for both polymeric sorbents is greatly affected by the solution pH and MgSO4 concentration in the aqueous phase, and a high recovery efficiency of pyruvic acid from aqueous solution can be obtained at the solution pH around 2.
基金Supported by the Natural Science Foundation of Jilin Province (No.990337).
文摘This research deals with an investigation of the adsorption of two acids, namely, 5-amino- 2-chlorotoluene-4-sulfonic and chlorhydric acids from their solution onto weakly basic resin. The screening of res-ins, kinetics, and isotherm were studied. The results indicate that the D301R is more appropriate for the removal of acids from solution. The adsorption of acids obeys Langmuir isotherm and the first-order kinetics model. Sorptive affinity of the two acids on D301R was found to be in the order of 5-amino-2-chlorotoluene-4-sulfonic acid> chlorhydric acid. Thermodynamic parameters for the adsorption of acids were calculated and discussed. The maxi-mum removal of acids was observed around 97% and 76% at 25℃ for 5-amino-2-chlorotoluene-4-sulfonic acid and chlorhydric acid , respectively.
文摘Experiments for single and bisolute competitive adsorption were carried out to investigate the adsorption behavior of β-naphthalenesulfonic acid(NSA) and sulfuric acid (H_2SO_4) from their solution at 25℃ onto weakly basic resin D301R. Adsorption affinity of sulfuric acid on D301R was found to be much higher than that of NSA. The data of single-solute adsorption were fitted to the Langmuir model and the Freundlich adsorption model. The ideal adsorbed solution theory(IAST) coupled with the single-solute adsorption models were used to predict the bisolute competitive adsorption equilibria. The IAST coupled with the Langmuir and the Freundlich model for sulfuric acid and NSA, respectively, yields the favorable representation of the bisolute competitive adsorption behavior.
基金Supported by the Natural Science Foundation of Jilin Province (No. 990337).
文摘Experiments for single and bisolute competitive adsorption were carried out to investigate the adsorption behavior of /3-naphthalenesulfonic acid (NSA) and sulfuric acid from their solution at 25C onto weakly basic resin D301R. Adsorption affinity of sulfuric acid on D301R was found to be much higher than that of NSA. The data of single-solute adsorption were fitted to the Langmuir model and the Preundlich adsorption model. The ideal adsorbed solution theory (IAST) coupled with the single-solute adsorption models were used to predict the bisolute competitive adsorption equilibria. The IAST coupled with the Langmuir and the Freundlich model for sulfuric acid and NSA, respectively, yields the favorable representation of the bisolute competitive adsorption behavior.
基金Project(2008F70059) supported by the Scientific and Technological Research Planning of Zhejiang Province, China
文摘The adsorption properties of a novel macroporous weak acid resin （D152） for Pb^2＋ were investigated with chemical methods. The optimal adsorption condition of D152 resin for Pb^2＋ is at pH 6.00 in HAc-NaAc medium. The statically saturated adsorption capacity is 527 mg/g at 298 K. Pb^2＋ adsorbed on D152 resin can be eluted with 0.05 mol/L HCI quantitatively. The adsorption rate constants determined under various temperatures are k288 n=2.22×10-5 s^-1, k298 K=2.51 × 10^-5 s^-1, and k308 K= 2.95 × 10^-5 s^-1, respectively. The apparent activation energy, Ea 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^Θ298 K =-22.2 kJ/mol, respectively. The adsorption behavior of D152 resin for Pb^2＋ follows Langmuir model.
文摘The adsorption equilibrium isotherms of three aromatic sulfonic acid compounds, 2-naphthalenesulfonic acid, p-toluenesulfonic acid and p-chlorobenzenesulfonic acid, from aqueous solutions by macroporous weak base anion exchanger within the temperature range of 293 K-313 K were obtained. Several isotherm equations were correlated with the equilibrium data, and the experimental data was found to fit the three-parameter Redlich-Peterson equation best within the entire range of concentrations. The study showed that the hydrophobicity of solute has distinct influence on adsorption capacity of the anion exchanger for the aromatic sulfonic acid. Moreover, estimations of the isosteric enthalpy, free energy, and entropy change of adsorption were also reported. The positive isosteric enthalpy and entropy change for adsorption indicate an endothermic and entropy driven process in the present study.
文摘Fluid coking on micro-spherical particles with acid sites on them could produce more light oils from Tahe AR.The conversion rate could increase by about 20% on the catalyst B compared to that obtained on the catalyst A and the light oil yield could increase by about 12%.The yield of gasoline and diesel was more than 50% from Tahe AR over the catalyst B.Tests on acidity of the catalyst B by pyridine FT-IR spectrometry showed that the total acid content and the ratio of weak acid number to total acid number were higher than other catalysts.
基金Project (Y404279) supported by the Natural Science Foundation of Zhejiang Province, China
文摘The adsorption properties of a novel gel-type weak acid resin (110-H) for Pb2+ were investigated using chemical methods and IR spectrometry.The optimal adsorption condition of 110-H for Pb2+ is at pH=6.49 in HAc-NaAc medium and the statically saturated adsorption capacity is 485 mg/g at 298 K.Pb2+ 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,ΔH=20.9 kJ/mol,ΔS=161 J/(mol.K) and ΔG298 K =-48.0 kJ/mol,respectively.The adsorption behavior of 110-H resin for Pb2+ accords with the Langmuir isotherm.Infrared spectra show that the oxygen atoms of the functional group of resin coordinate with Pb2+ to form the coordination bands.
基金The study was supported by the Nature Science Foundation of Jilin Province (No. 990337).
文摘Objective To study the adsorption of 5-Amino-2-chlorotoluene-4-sulfonic (CLT) and chlorhydric (HCl) acids from wastewater by weakly basic resin. Methods The kinetics and isotherm were studied. Thermodynamic parameters for the adsorption of acids were calculated and discussed. Results The adsorption of CLT and HCl acids followed Langmuir isotherm and the first-order kinetics model. Conclusion The adsorptive affinity of the two acids on D301R is in the order of CLT acid 〉 HCl acid. CLT and HCl acids can be separated.
文摘pH-fixed titration method for the determination of weak acids and bases has been studied in this paper.It is not necessary to know the ionization constant of weak acid or base and the concentration of titrant. This method had been applied to determine phenol,4-aminoantipyrine and glycine,whose ionization constants range from 10^(-10)to 10^(-12).The results were satisfactory.
文摘The “overlapping equilibria” effect observed in the processes of electrolytic dissociation of many weak multibasic organic acids determines the character of these processes. In this communication, the degree of “overlapping equilibria” in case of weak dibasic organic acids is quantitatively characterized by the values of “partial” degree of dissociation for second step and ratio of the concentrations of dianion and monoanion. It has been shown that these dissociation parameters are directly connected with the values of the second dissociation constant. It has been also shown that the contribution of third dissociation step in the “overlapping equilibria” effect is especially appreciable in case of penta and hexabasic weak organic acids causing the double “overlapping” phenomenon.
文摘A new method for the determination of ionization constants of polyprotic weak acids is presented. Based on dissociation equilibrium,mass balance and charge balance, the mathematic model is established and the non linear least squares Gauss Newton method is applied to numerically solve the model equations. In order to get the concentration of hydrogen ion, the Debye Hückel equation is used to calculate its activity coefficient. The ionization constants of H 2SO 3 and H 2C 2O 4 obtained by this method are in good agreement with the literature values.
文摘This paper reports a new method of titration for very weak acids and bases using the appearance of incisions on oscillopolarogram to indicate the end-point.This method has the advantages of rapidity,simplicity,no indicator needed as well as good precision.
文摘模拟投料环境,探索温度、时间、氧化剂NaClO、弱碱NaHCO_(3)、弱酸NaHSO_(3)对DTD分解情况的影响。结果表明:温度低于15℃时DTD分解缓慢,高于15℃时DTD分解迅速,且随时间的延长分解加剧。氧化剂NaClO会造成产物的迅速分解,4 h DTD分解剩余24.53%。NaHCO_(3)、NaHSO_(3)的加入对DTD的分解影响较小。为避免长时间对收率的影响,合成结束后需迅速进行后处理,对后期工业化生产具有重要的指导意义。
