共查询到20条相似文献,搜索用时 312 毫秒
1.
Xuemei Ren Suowei Wang Shitong Yang Jiaxing Li 《Journal of Radioanalytical and Nuclear Chemistry》2010,283(1):253-259
The sorption of U(VI) from aqueous solution on MX-80 bentonite was studied as a function of contact time, pH, ionic strength,
solid contents, humic acid (HA), fulvic acid (FA) and temperature under ambient conditions using batch technique. The results
indicate that sorption of U(VI) on MX-80 bentonite is strongly dependent on pH and ionic strength. The removal of U(VI) to
MX-80 bentonite is rather quick and the kinetic sorption data is simulated well by a pseudo-second-order rate equation. The
presence of HA enhances the sorption of U(VI) on MX-80 bentonite obviously, but the influence of FA on U(VI) sorption is not
obvious. The thermodynamic parameters (ΔH
0, ΔS
0, and ΔG
0) for the sorption of U(VI) calculated from temperature dependent sorption suggest that the sorption reaction is endothermic
and spontaneous. 相似文献
2.
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
3.
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
4.
Dong Lijia Yang Jianxia Mou Yinyan Sheng Guodong Wang Linxia Linghu Wensheng Asiri Abdullah M. Alamry Khalid A. 《Journal of Radioanalytical and Nuclear Chemistry》2017,314(1):377-386
Herein, we used biochar pyrolyzed from rice straw to adsorb uranium (U) from aqueous solutions. The adsorption of U(VI) on biochar was strongly dependent on pH but independent on ionic strength. HA/FA enhanced the sorption at pH <6.8 while inhibited the sorption at pH >6.8. The sorption reached equilibrium within 3 h, which was not mediated by pH. The adsorption process was spontaneous and endothermic, and enhanced at higher temperature. However, the influence of temperature was negligible at low initial U(VI) concentrations. Therefore, biochar derived from rice straw may be a promising adsorbent for the removal of U(VI).
相似文献5.
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
6.
P. Chang S. Yu T. Chen A. Ren C. Chen X. Wang 《Journal of Radioanalytical and Nuclear Chemistry》2007,274(1):153-160
Sorption of Th(IV) on Na-rectorite as a function of pH, ionic strength, soil humic acid (HA) and fulvic acid (FA) are studied
under ambient conditions by using a batch technique. The results indicate that the sorption of Th(IV) on Na-rectorite is not
only dependent on medium pH values, but also dependent on medium ionic strength and humic substances. Surface complexation
and cation competition exchange account for Th(IV) sorption on Na-rectorite. The sorption of Th(IV) on Na-rectorite decreases
with the increase on the concentration of NaNO3, Mg(NO3)2 and Ca(NO3)2, and increases with the increasing amount of HA/FA in the suspension/adsorbed on rectorite. Soil HA/FA enhances the sorption
of Th(IV) on rectorite at medium pH<4 drastically, but the presence of FA reduces the sorption of Th(IV) at medium pH>6, and
HA has no effect on Th(IV) sorption at medium pH>6. An interpretation for the results is attempted, considering the occurrence
of different sorption mechanisms. 相似文献
7.
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
8.
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
9.
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
10.
Modified Sorrel’s cement was prepared by the addition of ferric chloride. The modified cement (MF5) was analyzed and characterized
by different methods. Adsorption of Gd(III) and U(VI) ions in carbonate solution has been studied separately as a function
of pH, contact time, adsorbent weight, carbonate concentration, concentration of Gd(III) and U(VI) and temperature. From equilibrium
data obtained, the values of Δ H, Δ S and Δ G were found to equal −30.9 kJ ⋅ mol−1, −85.4 J ⋅ mol−1 ⋅,K−1, and −5.4 KJ ⋅ mol−1, respectively, for Gd(III) and 18.9 kJ ⋅ mol−1, 67.8 J ⋅ mol−1 K−1 and −1.3 KJ ⋅ mol−1, respectively, for U(VI). The equilibrium data obtained have been found to fit both Langmuir and Freundlich adsorption isotherms.
The batch kinetic of Gd(III) and U(VI) on modified Sorrel’s cement (MF5) with the thermodynamic parameters from carbonate
solution were studied to explain the mechanistic aspects of the adsorption process. Several kinetic models were used to test
the experimental rate data and to examine the controlling mechanism of the adsorption process. Various parameters such as
effective diffusion coefficient and activation energy of activation were evaluated. The adsorption of Gd(III) and U(VI) on
the MF5 adsorbent follows first-order reversible kinetics. The forward and backward constants for adsorption, k
1and k
2 have been calculated at different temperatures between 10 and 60∘C. Form kinetic study, the values of Δ H
* and Δ S
* were calculated for Gd(III) and U(VI) at 25∘C. It is found that Δ H
* equals −14.8 kJmol−1 and 7.2 kJmol−1 for Gd(III) and U(VI), respectively, while Δ S
* were found equal −95.7 Jmol−1K−1 and −70.5 Jmol−1K−1 for Gd(III) and U(VI), respectively. The study showed that the pore diffusion is the rate limiting for Gd(III) and (VI). 相似文献
11.
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
12.
Yan Huang Hualin Wang Shengdong Gong 《Journal of Radioanalytical and Nuclear Chemistry》2012,292(2):545-553
In this work, hydroxyapatite (HAP) was prepared by aqueous precipitation technique and was characterized by using FT-IR to
determine its chemical functional groups. A series of batch experiments were carried out to investigate the effect of various
environmental factors such as contact time, pH, ionic strength, foreign ions, fulvic acid (FA) and temperature on the sorption
behavior of HAP towards radionuclide 109Cd(II). The results indicated that the sorption of 109Cd(II) on HAP was strongly dependent on pH and ionic strength. A positive effect of FA on 109Cd(II) sorption was found at pH <7.0, whereas a negative effect was observed at pH >7.0. The Langmuir, Freundlich and D-R
models were used to simulate the sorption isotherms at three different temperatures of 298.15, 323.15 and 343.15 K. The thermodynamic
parameters (ΔH0, ΔS0 and ΔG0) calculated from the temperature dependent sorption isotherms indicated that the sorption process of 109Cd(II) on HAP was spontaneous and endothermic. At low pH, the sorption of 109Cd(II) was dominated by outer-sphere surface complexation and ion exchange on HAP surfaces, whereas inner-sphere surface complexation
was the main sorption mechanism at high pH. From the experimental results, it is possible to conclude that HAP has good potentialities
for cost-effective treatments of 109Cd(II)-contaminated wastewaters. 相似文献
13.
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
14.
The mesoporous molecular sieves (Al-MCM-41) are synthesized with montmorillonite as silica–alumina source by hydrothermal
method. The application of Al-MCM-41 for the adsorption of Th(IV) from aqueous solution is studied by batch technique. The
effects of contact time, solid content, pH, ionic strength, foreign ions, and temperature are determined, and the results
indicate that the adsorption of Th(IV) to Al-MCM-41 is strongly dependent on pH values but independent of ionic strength.
The adsorption isotherms are simulated by D–R and Freundlich models well. The thermodynamic parameters (ΔH
0, ΔS
0, ΔG
0) are calculated from the temperature dependent adsorption isotherms at 293, 313 and 333 K, respectively, and the results
suggest that the adsorption of Th(IV) on Al-MCM-41 is a spontaneous and endothermic process. Al-MCM-41 is a suitable material
for the preconcentration of Th(IV) from large volumes of aqueous solutions. 相似文献
15.
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
16.
In this paper, the crosslinked polyester resin containing acrylic acid functional groups was used for the adsorption of uranium
ions from aqueous solutions. For this purpose, the crosslinked polyester resin of unsaturated polyester in styrene monomer
(Polipol 353, Poliya) and acrylic acid as weight percentage at 80 and 20%, respectively was synthesized by using methyl ethyl
ketone peroxide (MEKp, Butanox M60, Azo Nobel)-cobalt octoate initiator system. The adsorption of uranium ions on the sample (0.05 g copolymer
and 5 mL of U(VI) solution were mixed) of the crosslinked polyester resin functionalized with acrylic acid was carried out
in a batch reactor. The effects of adsorption parameters of the contact time, temperature, pH of solution and initial uranium(VI)
concentration for U(VI) adsorption on the crosslinked polyester resin functionalized with acrylic acid were investigated.
The adsorption data obtained from experimental results depending on the initial U(VI) concentration were analyzed by the Freundlich,
Langmuir and Dubinin–Radushkevich (D–R) adsorption isotherms. The adsorption capacity and free energy change were determined
by using D–R isotherm. The obtained experimental adsorption data depending on temperature were evaluated to calculate the
thermodynamic parameters of enthalpy (ΔH°), entropy (ΔS°) and free energy change (ΔG°) for the U(VI) adsorption on the crosslinked polyester resin functionalized with acrylic acid from aqueous solutions. The
obtained adsorption data depending on contact time were analyzed by using adsorption models such as the modified Freundlich,
Elovich, pseudo-first order and pseudo-second-order kinetic models. 相似文献
17.
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
18.
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
19.
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
20.
Yating Liu Yunhai Liu Xiaohong Cao Rong Hua Youqun Wang Cui Pang Ming Hua Xiaoyan Li 《Journal of Radioanalytical and Nuclear Chemistry》2011,290(2):231-239
The cross-linked chitosan (CS) gels synthesized by using glutaraldehyde (GLA), epichlorohydrin (EC), and ethylene glycol diglycidyl
ether (EGDE) as cross-linkers respectively were used to investigate the adsorption of U(VI) ions in an aqueous solution. The
pure chitosan (PCS) and the cross-linked chitosan gels were characterized by FTIR and SEM analysis. The kinetic, thermodynamic
adsorption and adsorption isotherms of U(VI) ions onto unmodified and modified cross-linked chitosan were studied in a batch
adsorption experiments. The effect of pH, contact time and temperature on the adsorption capacity were also carried out. At
the optimum pH, the maximum adsorbed amount of PCS, GLACS, ECCS and EGDECS were 483.05, 147.05, 344.83 and 67.56 mg/g, respectively.
The uranium (VI) adsorption process of PCS and ECCS followed better with pseudo-second-order kinetic model, while GLACS and
EGDECS followed pseudo-first-order kinetic model well. The results obtained from the equilibrium isotherms adsorption studied
of U(VI) ions were analyzed in two adsorption models, namely, Langmuir and Freundlich isothms models, the results showed that
the Langmuir isotherm had better conformity to the equilibrium data. The thermodynamic parameters such as enthalpy (ΔHo), entropy (ΔSo), and Gibbs free energy (ΔGo) showed that the adsorption process was both spontaneous and endothermic. 相似文献