共查询到20条相似文献,搜索用时 78 毫秒
1.
Yan Huang Liang Chen Hualin Wang 《Journal of Radioanalytical and Nuclear Chemistry》2012,291(3):777-785
Herein, hydroxyapatite (HAP) was prepared by aqueous precipitation technique and was characterized by using FT-IR and XRD
to determine its chemical functional groups and micro-structure. The removal of cobalt from aqueous solution to HAP was studied
by batch technique as a function of various environmental parameters such as contact time, pH, ionic strength, foreign ions,
fulvic acid (FA), and temperature under ambient conditions. The results indicated that the sorption of Co(II) on HAP was strongly
dependent on pH and ionic strength. The presence of FA enhanced the sorption of Co(II) on HAP at low pH, whereas reduced Co(II)
sorption on HAP at high pH. The Langmuir, Freundlich and D-R models were used to simulate the sorption isotherms at three
different temperatures of 303.15, 323.15 and 343.15 K. The thermodynamic parameters (ΔH°, ΔS° and ΔG°) calculated from the temperature dependent sorption isotherms indicated that the sorption process of Co(II) on HAP was spontaneous
and endothermic. The sorption of Co(II) was dominated by outer-sphere surface complexation and ion exchange at low pH, whereas
inner-sphere surface complexation or surface precipitation was the main sorption mechanism at high pH values. The results
suggest that the HAP is a suitable material in the preconcentration and solidification of Co(II) from large volumes of aqueous
solutions. 相似文献
2.
Yunhui Dong Zhengjie Liu Yueyun Li Lei Chen Zengchao Zhang 《Journal of Radioanalytical and Nuclear Chemistry》2012,292(2):619-627
The sorption of Cd(II) from aqueous solution on γ-Al2O3 was investigated under ambient conditions. Experiments were carried out as a function of contact time, solid content, pH,
ionic strength, foreign ions, fulvic acid and temperature. The results indicated that the sorption of Cd(II) was strongly
dependent on pH and ionic strength. At low pH, the sorption of Cd(II) was dominated by outer-sphere surface complexation and
ion exchange with Na+/H+ on γ-Al2O3 surfaces, whereas inner-sphere surface complexation was the main sorption mechanism at high pH. The Langmuir, Freundlich
and Dubinin–Radushkevich (D–R) models were used to simulate the sorption isotherms at three different temperatures. The thermodynamic
data (ΔG
0, ΔS
0, ΔH
0) calculated from the temperature dependent sorption isotherms suggested that the sorption of Cd(II) on γ-Al2O3 was an spontaneous and endothermic process. 相似文献
3.
Tanveer Hussain Bokhari A. Mushtaq Islam Ullah Khan 《Journal of Radioanalytical and Nuclear Chemistry》2010,285(2):389-398
In this work, sorption of Ni(II) from aqueous solution to goethite as a function of various water quality parameters and temperature
was investigated. The results indicated that the pseudo-second-order rate equation fitted the kinetic sorption well. The sorption
of Ni(II) to goethite was strongly dependent on pH and ionic strength. A positive effect of HA/FA on Ni(II) sorption was found
at pH < 8.0, whereas a negative effect was observed at pH > 8.0. The Langmuir, Freundlich, and D-R models were applied to
simulate the sorption isotherms at three different temperatures of 293.15 K, 313.15 K and 333.15 K. The thermodynamic parameters
(ΔH
0, ΔS
0 and ΔG
0) were calculated from the temperature dependent sorption, and the results indicated that the sorption was endothermic and
spontaneous. At low pH, the sorption of Ni(II) was dominated by outer-sphere surface complexation or ion exchange with Na+/H+ on goethite surfaces, whereas inner-sphere surface complexation was the main sorption mechanism at high pH. 相似文献
4.
Lipeng Zhang Hui Zhang Zhiwei Ge Xianjin Yu 《Journal of Radioanalytical and Nuclear Chemistry》2011,288(2):537-546
The fate and transport of toxic metal ions and radionuclides in the environment is generally controlled by sorption reactions.
The removal of 60Co(II) from wastewaters by MnO2 was studied as a function of various environmental parameters such as shaking time, pH, ionic strength, foreign ions, and
humic substances under ambient conditions. The results indicated that the sorption of 60Co(II) on MnO2 was strongly dependent on pH and ionic strength. At low pH, the sorption of 60Co(II) was dominated by outer-sphere surface complexation and ion exchange with Na+/H+ on MnO2 surfaces, whereas inner-sphere surface complexation was the main sorption mechanism at high pH. The presence of HA/FA enhances
60Co(II) sorption at low pH values, whereas reduces 60Co(II) sorption at high pH values. The Langmuir and Freundlich models were used to simulate the sorption isotherms of 60Co(II) at three different temperatures of 298.15, 318.15 and 338.15 K. The thermodynamic parameters (ΔH
0, ΔS
0 and ΔG
0) calculated from the temperature dependent sorption isotherms indicated that the sorption process of 60Co(II) on MnO2 was endothermic and spontaneous. 相似文献
5.
Zhiqiang Guo Donglin Zhao Yuan Li Zhesheng Chen Haihong Niu Jinzhang Xu 《Journal of Radioanalytical and Nuclear Chemistry》2011,288(3):829-837
The sorption of radiocadmium on Ca-montmorillonite as a function of contact time, pH, ionic strength, foreign ions, humic acid (HA) and fulvic acid (FA) was studied using batch technique. The results demonstrated that the sorption of Cd(II) was dependent on ionic strength at pH < 9, and was independent of ionic strength at pH > 9. Outer-sphere surface complexation and/or ion exchange were the main mechanism of Cd(II) sorption on Ca-montmorillonite at low pH, whereas the sorption at high pH was mainly dominated via inner-sphere surface complexation. The sorption of Cd(II) on Ca-montmorillonite was dependent on foreign ions at low pH values, but was independent of foreign ions at high pH values. A positive effect of HA/FA on Cd(II) sorption was found at low pH values, whereas a negative effect was observed at high pH values. The thermodynamic parameters (i.e., ??H 0, ??S 0, ??G 0) were calculated from the temperature dependent sorption isotherms, and the results indicated that the sorption process of Cd(II) on Ca-montmorillonite was spontaneous and endothermic. 相似文献
6.
Juan Mou Guoju Wang Wenxian Shi Shouwei Zhang 《Journal of Radioanalytical and Nuclear Chemistry》2012,292(1):161-170
A novel hierarchically structured γ-MnO2 has been synthesized using a simple chemical reaction between MnSO4 and KMnO4 in aqueous solution without using any templates, surfactants, catalysts, calcination and hydrothermal processes. As an example
of potential applications, hierarchically structured γ-MnO2 was used as adsorbent in radionuclide 63Ni(II) treatment, and showed an excellent ability. The effects of pH, ionic strength, temperature, humic acid (HA) and fulvic
acid (FA) on the sorption of radionuclide 63Ni(II) to hierarchically structured γ-MnO2 have been investigated by using batch techniques. The results indicated that the sorption of 63Ni(II) on γ-MnO2 is obviously dependent on pH values but independent of ionic strength. The presence of HA/FA strongly enhances the sorption
of 63Ni(II) on γ-MnO2 at low pH values, whereas reduces 63Ni(II) sorption at high pH values. The sorption of 63Ni(II) on γ-MnO2 is attributed to inner-sphere surface complexation rather than outer-sphere surface complexation or ion exchange. The thermodynamic
parameters (ΔH
0, ΔS
0, ΔG
0) are also calculated from the temperature dependent sorption isotherms, and the results suggest that the sorption of 63Ni(II) on γ-MnO2 is a spontaneous and endothermic process. 相似文献
7.
Yunhui Dong Zhengjie Liu Lei Chen 《Journal of Radioanalytical and Nuclear Chemistry》2012,292(1):435-443
Clay minerals have been widely used in wastewater disposal due to their strong sorption and complexation ability towards various
environmental pollutants. In this study, the removal of Zn(II) from aqueous solution by natural halloysite nanotubes (HNTs)
was studied as a function of various solution chemistry conditions such as contact time, pH, ionic strength, coexisting electrolyte
ions and temperature under ambient conditions. The results indicated that the removal of Zn(II) by HNTs was strongly dependent
on pH and ionic strength. Langmuir and Freundlich models were used to simulate the sorption isotherms of Zn(II) at three different
temperatures of 293, 313 and 333 K. The thermodynamic parameters (ΔH
0, ΔS
0 and ΔG
0) calculated from the temperature dependent sorption isotherms indicated that the removal process of Zn(II) by HNTs was endothermic
and spontaneous. At low pH, the removal of Zn(II) was dominated by outer-sphere surface complexation and/or cation exchange
with Na+/H+ on HNT surfaces, whereas inner-sphere surface complexation was the main removal mechanism at high pH. From the experimental
results, one can conclude that HNTs may have a good potentiality for the disposal of Zn(II)-bearing wastewaters. 相似文献
8.
Effect of environmental conditions on the sorption of radiocobalt from aqueous solution to treated eggshell as biosorbent 总被引:1,自引:0,他引:1
Shouwei Zhang Zhiqiang Guo Junzheng Xu Haihong Niu Zhesheng Chen Jinzhang Xu 《Journal of Radioanalytical and Nuclear Chemistry》2011,288(1):121-130
Carbonate hydroxylapatite (CHAP), prepared from eggshell waste, was used to remove 60Co(II) from aqueous solutions. The sorption of 60Co(II) on CHAP as a function of contact time, pH, ionic strength and foreign ions in the absence and presence of humic acid
and fulvic acid under ambient conditions was studied. The sorption of 60Co(II) on CHAP was strongly dependent on pH and ionic strength. The thermodynamic parameters (ΔH
0, ΔS
0, ΔG
0) of 60Co(II) sorption on CHAP were calculated from the temperature-dependent sorption isotherms, and the results indicated that
the sorption process of 60Co(II) on CHAP was endothermic and spontaneous. At low pH, the sorption of 60Co(II) was dominated by outer-sphere surface complexation and ion exchange with Na+/H+ on CHAP surfaces, whereas inner-sphere surface complexation was the main sorption mechanism at high pH. Experimental results
also indicated that CHAP was a suitable low-cost adsorbent for pre-concentration and solidification of 60Co(II) from large volumes of aqueous solutions. 相似文献
9.
Juan Mou Guoju Wang Wenxian Shi Shouwei Zhang 《Journal of Radioanalytical and Nuclear Chemistry》2012,292(1):293-303
A novel γ-MnO2 hollow structure has been synthesized using a simple chemical reaction between MnSO4 and KMnO4 in aqueous solution without using any templates, surfactants, catalysts, calcination and hydrothermal processes. As an example
of potential applications, γ-MnO2 hollow structure was used as adsorbent in radionuclide 60Co(II) treatment, and showed an excellent ability. The effect of pH, contact time, ionic strength, humic acid (HA)/fulvic
acid (FA), and temperature was investigated using batch techniques. The results indicated that the sorption of 60Co(II) on γ-MnO2 was obviously dependent on pH values but independent of ionic strength. The presence of HA/FA enhanced the sorption of 60Co(II) on γ-MnO2 at low pH, whereas reduced 60Co(II) sorption on γ-MnO2 at high pH. The kinetic sorption of 60Co(II) on γ-MnO2 can be well fitted by the pseudo-second-order rate equation. The thermodynamic parameters (ΔH
0, ΔS
0, ΔG
0) were also calculated from the temperature dependent sorption isotherms, and the results suggested that the sorption of 60Co(II) on γ-MnO2 was a spontaneous and endothermic process. The sorption of 60Co(II) on γ-MnO2 was attributed to surface complexation rather than ion exchange. 相似文献
10.
Caicai Zhang Zhengjie Liu Lei Chen Yunhui Dong 《Journal of Radioanalytical and Nuclear Chemistry》2012,292(1):411-419
The sorption of 60Co(II) on γ-Al2O3 was conducted under various conditions, i.e., contact time, adsorbent content, pH, ionic strength, foreign ions, humic acid
(HA), and temperature. Results of sorption data analysis indicated that the sorption of 60Co(II) on γ-Al2O3 was strongly dependent on pH and ionic strength. At low pH the sorption was dominated by outer-sphere surface complexation
or ion exchange, whereas inner-sphere surface complexation was the main sorption mechanism at high pH. The presence of different
cation ions influenced 60Co(II) sorption, while the presence of different anion ions had no obvious influences on 60Co(II) sorption. The presence of HA decreased the sorption of 60Co(II) on γ-Al2O3. The sorption isotherms were simulated well with the Langmuir model. The thermodynamic parameters (ΔH
0
, ΔS
0
and ΔG
0
) calculated from the temperature-dependent sorption isotherms indicated that the sorption of 60Co(II) on γ-Al2O3 was an endothermic and spontaneous process. Experimental results indicated that the low cost material was a suitable material
in the preconcentration of 60Co(II) from large volumes of aqueous solutions. 相似文献
11.
Shouwei Zhang Haihong Niu Zhiqiang Guo Zhesheng Chen Haiping Wang Jinzhang Xu 《Journal of Radioanalytical and Nuclear Chemistry》2011,289(2):479-487
A novel adsorbent, TiO2/eggshell composite, was synthesized by sol–gel method, and characterized by XRD and FTIR. The removal of 60Co(II) from aqueous solution by TiO2/eggshell was studied as a function of contact time, pH, ionic strength, foreign ions, humic substances and temperature. The
results indicated that the sorption of 60Co(II) on TiO2/eggshell was strongly dependent on pH and ionic strength. The Langmuir, Freundlich and D-R models were applied to simulate
the sorption of 60Co(II) at temperatures of 303.15, 323.15 and 343.15 K. The thermodynamic parameters (ΔH
0, ΔS
0, ΔG
0) calculated from the temperature dependent sorption isotherms indicated that the sorption process of 60Co(II) on TiO2/eggshell was endothermic and spontaneous. At low pH, the sorption of 60Co(II) was dominated by outer-sphere surface complexation or ion exchange, whereas inner-sphere surface complexation was the
main sorption mechanism at high pH. TiO2/eggshell composites have good potentialities for cost-effective disposal of 60Co(II) bearing wastewaters. 相似文献
12.
Zhiqiang Guo Dapeng Xu Donglin Zhao Shouwei Zhang Jinzhang Xu 《Journal of Radioanalytical and Nuclear Chemistry》2011,287(2):505-512
This work contributed to the adsorption of radiocobalt on goethite as a function of contact time, pH, ionic strength and foreign
ions in the absence and presence of fulvic acid (FA) under ambient conditions. The results indicated that adsorption of Co(II)
was dependent on ionic strength and foreign ions at low pH values (pH < 7.8), and independent of ionic strength and foreign
ions at high pH values (pH > 7.8). Outer-sphere surface complexation and/or ion exchange were the main mechanisms of Co(II)
adsorption on goethite at low pH values, whereas inner-sphere surface complexation was the main adsorption mechanism at high
pH values. The presence of FA enhanced Co(II) adsorption at low pH values, but reduced Co(II) adsorption at high pH values.
The thermodynamic data (ΔH
0, ΔS
0, ΔG
0) were calculated from the temperature dependent adsorption isotherms, and the results suggested that adsorption process of
Co(II) on goethite was spontaneous and endothermic. The results are crucial to understand the physicochemical behavior of
Co(II) in the nature environment. 相似文献
13.
In this work, a series of batch experiments were carried out to investigate the effect of various environmental factors such
as contact time, pH, ionic strength, coexisting electrolyte ions, humic substances and temperature on the sorption behavior
of illite towards 64Cu(II). The results indicated that 64Cu(II) sorption on illite achieved equilibrium quickly. The pH- and ionic strength-dependent sorption suggested that 64Cu(II) sorption on illite was dominated by ion exchange or outer-sphere surface complexation at pH < 7, whereas the pH-dependent
and ionic strength-independent sorption indicated that the sorption process was mainly attributed to inner-sphere surface
complexation at pH > 7. A positive effect of humic substances on 64Cu(II) sorption was found at pH < 6.5, whereas a negative effect was observed at pH > 6.5. The Langmuir and Freundlich models
were used to simulate the sorption isotherms of 64Cu(II) at three different temperatures of 293, 313, and 333 K. The thermodynamic parameters (ΔH
0, ΔS
0, and ΔG
0) of 64Cu(II) sorption on illite were calculated from the temperature dependent sorption isotherms, and the results indicated that
the sorption of 64Cu(II) on illite was endothermic and spontaneous. From the experimental results, it is possible to conclude that illite has
good potentialities for cost-effective treatments of 64Cu(II)-contaminated wastewaters. 相似文献
14.
Kan Li Zhengjie Liu Tao Wen Lei Chen Yunhui Dong 《Journal of Radioanalytical and Nuclear Chemistry》2012,292(1):269-276
In this paper, the sorption of Co(II) from aqueous solution to Ca-montmorillonite was studied under ambient conditions by
using batch technique. The effects of contact time, solid content, pH, ionic strength and temperature on the sorption of Co(II)
to Ca-montmorillonite was also investigated. The results indicated that the sorption of Co(II) was strongly dependent on pH
values. The sorption was dependent on ionic strength at low pH values, but independent of ionic strength at high pH values.
Outer-sphere surface complexes were formed on the surface of Ca-montmorillonite at low pH values, whereas inner-sphere surface
complexes were formed at high pH values. The Langmuir, Freundlich and Dubinin–Radushkevich (D–R) models were used to simulate
the sorption isotherms of Co(II) at three different temperatures. The thermodynamic parameters (ΔH
0, ΔS
0 and ΔG
0) were calculated from the temperature dependent sorption isotherms, and the results indicated that the sorption reaction
of Co(II) to Ca-montmorillonite was an endothermic and spontaneous process. The high sorption capacity of Co(II) on Ca-montmorillonite
suggests that the Ca-montmorillonite is a suitable material for the preconcentration and solidification of radiocobalt from
aqueous solutions. 相似文献
15.
Zhengjie Liu Lei Chen Yunhui Dong Zengchao Zhang 《Journal of Radioanalytical and Nuclear Chemistry》2011,289(3):851-859
The sorption of Co(II) from aqueous solution on Na-rectorite was investigated under ambient conditions. Experiments were carried
out as a function of contact time, solid content, pH, ionic strength, foreign ions, fulvic acid and temperature. The results
indicated that the sorption of Co(II) was strongly dependent on pH. At low pH the sorption was dominated by outer-sphere surface
complexation or ion exchange, whereas inner-sphere surface complexation was the main sorption mechanism at high pH. The Langmuir,
Freundlich and Dubinin–Radushkevich (D–R) models were used to simulate the sorption isotherms at three different temperatures.
The thermodynamic data (∆G
0, ∆S
0, ∆H
0) were calculated from the temperature dependent sorption isotherms and the results suggested that the sorption process of
Co(II) on Na-rectorite was spontaneous and endothermic. Experimental results indicate that Na-rectorite is a suitable adsorbent
for preconcentration and solidification of Co(II) from large volumes of aqueous solutions. 相似文献
16.
The sorption of Cd(II) from aqueous solution on MnO2 was investigated under ambient conditions. Experiments were carried out as a function of contact time, solid content, pH, ionic strength, foreign ions, fulvic acid and temperature. The results indicated that the sorption of Cd(II) was strongly dependent on pH and ionic strength. At low pH, the sorption of Cd(II) was dominated by outer-sphere surface complexation and ion exchange with Na+/H+ on MnO2 surfaces, whereas inner-sphere surface complexation was the main sorption mechanism at high pH. The Langmuir, Freundlich and Dubinin–Radushkevich models were used to simulate the sorption isotherms at three different temperatures. The thermodynamic data (ΔG 0, ΔS 0, ΔH 0) calculated from the temperature dependent sorption isotherms suggested that the sorption of Cd(II) on MnO2 was an spontaneous and endothermic process. 相似文献
17.
Liqiang Tan Yeling Jin Jing Chen Xiaochun Cheng Jie Wu Liangdong Feng 《Journal of Radioanalytical and Nuclear Chemistry》2011,289(2):601-610
The sorption of Co(II) on Na-attapulgite as a function of contact time, solid content, pH, ionic strength, foreign ions, fulvic
acid (FA) and temperature under ambient conditions was studied. The kinetic of Co(II) sorption on Na-attapulgite was described
well by pseudo-second-order model. The sorption of Co(II) on Na-attapulgite was strongly dependent on pH and ionic strength.
The sorption of Co(II) was mainly dominated by outer-sphere surface complexation and/or ion exchange at low pH, whereas inner-sphere
surface complexation or surface precipitation was the main sorption mechanism at high pH values. The presence of FA did not
affect Co(II) sorption obviously at pH <7, and a negative effect was observed at pH >7. The Langmuir and Freundlich models
were used to simulate the sorption data at different temperatures, and the results indicated that the Langmuir model simulated
the data better than the Freundlich isotherm model. The thermodynamic parameters (∆G°, ∆S°,
∆H°) calculated from the temperature-dependent sorption isotherms indicated that the sorption of Co(II) on Na-attapulgite was
an endothermic and spontaneous process. The results suggest that the attapulgite sample is a suitable material in the preconcentration
and solidification of radiocobalt from large volumes of aqueous solutions. 相似文献
18.
Hui Zhang Xianjin Yu Lei Chen Jiaqiang Geng 《Journal of Radioanalytical and Nuclear Chemistry》2010,286(1):249-258
The sorption of 63Ni(II) from aqueous solution using ZSM-5 zeolite was investigated by batch technique under ambient conditions. ZSM-5 zeolite
was characterized by point of zero net proton charge (PZNPC) titration. The sorption was investigated as a function of shaking
time, pH, ionic strength, foreign ions, humic acid (HA), fulvic acid (FA) and temperature. The results indicate that the sorption
of 63Ni(II) on ZSM-5 zeolite is strongly dependent on pH. The sorption is dependent on ionic strength at low pH, but independent
of ionic strength at high pH values. The presence of HA/FA enhances 63Ni(II) sorption at low pH values, whereas reduces 63Ni(II) sorption at high pH values. The sorption isotherms are simulated by Langmuir model very well. The thermodynamic parameters
(i.e., ∆H
0, ∆S
0 and ∆G
0) for the sorption of 63Ni(II) are determined from the temperature dependent sorption isotherms at 293.15, 313.15 and 333.15 K, respectively, and
the results indicate that the sorption process of 63Ni(II) on ZSM-5 zeolite is spontaneous and endothermic. 相似文献
19.
Liu Xia Chen Yuantao Chi Yaling Guo Zhijun Cai Linsen 《Journal of Radioanalytical and Nuclear Chemistry》2012,292(3):1357-1366
In this article, a series of batch experiments were carried out to investigate the effect of various environmental factors
such as contact time, solid content, pH, ionic strength, foreign ions, temperature and coexisting humic acid on the sorption
behavior radionuclide 60Co(II) on illite. The results indicated that the sorption of Co(II) was strongly dependent on pH, ionic strength and temperature.
At low pH, the sorption was dominated by outer-sphere surface complexation and ion exchange on illite surfaces, whereas inner-sphere
surface complexation was the main sorption mechanism at high pH. The Langmuir, Freundlich and Dubinin-Radushkevich (D-R) models
were used to simulate the sorption isotherms at three different temperatures of 303.15, 323.15 and 343.15 K. The thermodynamic
data (∆G
0, ∆S
0, ∆H
0) were calculated from the temperature dependent sorption isotherms and the results suggested that the sorption process of
Co(II) on illite was an endothermic and spontaneous process. The sorption test revealed that the illite can be as a cost-effective
adsorbent suitable for pre-concentration of Co(II) from large volumes of aqueous solutions. 相似文献
20.
Lipeng Zhang Xianjin Yu Hui Zhang Enze Chen Tao Dong 《Journal of Radioanalytical and Nuclear Chemistry》2013,295(2):1473-1485
In this work, a naturally occurring illite was characterized by using FT-IR and XRD technique to determine its surface functional groups and crystal structure. Sorption of 60Co(II) on illite as a function of contact time, pH, ionic strength, foreign ions, humic substances and temperature was studied under ambient condition using batch technique. The results indicated that the sorption of 60Co(II) on illite is strongly affected by pH values (2–9) and ionic strength. A positive effect of humic substances on 60Co(II) sorption was found at pH < 7.0, whereas a negative effect was observed at pH > 7.0. At low pH, the sorption of 60Co(II) was dominated by outer-sphere surface complexation and ion exchange with Na+/H+ on illite surfaces, whereas inner-sphere surface complexation was the main sorption mechanism at high pH. The Langmuir and Freundlich models were used to simulate the sorption isotherms of 60Co(II) at three different temperatures of 298.15, 323.15 and 343.15 K. The thermodynamic parameters (ΔH 0, ΔS 0 and ΔG 0) calculated from the temperature dependent sorption isotherms indicated that the sorption process of 60Co(II) on illite was endothermic and spontaneous. 相似文献