Journal of Chemistry

Journal of Chemistry / 2016 / Article

Research Article | Open Access

Volume 2016 |Article ID 8617219 | 8 pages | https://doi.org/10.1155/2016/8617219

Removal of Arsenite from Water by Ce-Al-Fe Trimetal Oxide Adsorbent: Kinetics, Isotherms, and Thermodynamics

Academic Editor: José Morillo Aguado
Received25 Mar 2016
Accepted19 Jun 2016
Published14 Jul 2016

Abstract

Ce-Al-Fe trimetal oxide adsorbent was prepared. The morphology characteristics of the new adsorbent were analysed by the transmission electron microscope (SEM) method. The SEM results implied its ability in the adsorption of As (III). To verify the analyses, bench-scale experiments were performed for the removal of As (III) from water. In the experiments of adsorption, As (III) adsorption capacity of the trimetal oxide adsorbent was presented significantly higher than activated aluminium oxide and activated carbon. As (III) adsorption kinetics resembled pseudo-second-order adsorption mode. When initial As (III) concentration was 3, 8, and 10 mg·L−1, the maximum adsorption capacity achieved was 1.48, 3.73, and 5.12 mg·g−1, respectively. In addition, the experimental adsorption data were described well by the Freundlich adsorption isotherm model at 20, 30, and 40°C. The enthalpy change , the standard free energy , and entropy change indicated that the nature of As (III) adsorption was exothermic and spontaneous with increasing randomness on the interface of solid and liquid. And the adsorption mechanism can be interpreted as chemisorption with As (III) multilayer coverage formation on the adsorbent surface.

1. Introduction

Arsenic contamination of water, resulting from both natural processes and anthropogenic activities [13], has a great harm to human health and other living organisms due to the arsenic carcinogenicity and toxicity [4, 5]. In natural water, inorganic arsenic predominantly exists in two forms of As (III) and As (V) [6]. Compared with the latter, the former presented 25–60 times higher toxicity and is more mobile [7]. As (III) exists widely in sediment, surface water, and groundwater. Due to the existence of the reducing condition, the concentrated As (III) is released from sediment into water and this happened almost constantly [810]. Therefore, As (III) removal is becoming one of the hot topics in pollution incident emergency treatment and drinking water treatment researches.

Several technologies including adsorption [11], coagulation/precipitation [12], and ion exchange [13] have been used to remove As (III) from polluted surface water and water resources. When pH varied from weakly acidic to weakly alkaline in natural water, the hydrolyzed species of As (III) existed mainly in the form of nonionic H3AsO3 [8, 14]. For the removal of As (III), coagulation/precipitation technology is generally not effective at natural pH [15] because of As (III) uncharged form. Adsorption is considered as one of the most promising methods for As (III) removal due to high removal efficiency without yielding by-products. The key component of adsorption processes is the adsorbents that are expected to have high adsorption capacities toward As [16]. Some investigations already reported that the composite oxides adsorbents based on iron [17], titanium [18], manganese and alumina oxide [19, 20], Fe-Ni binary oxide [21], and Fe-Cu binary oxide [22] are effective for As removal. However, these adsorbents have relatively low adsorption capacity for As, and iron oxide-based adsorbent has received great attention due to the binding affinity for inorganic As and relatively low production costs [2325].

In recent years, hydrous cerium (Ce) oxide has been developed as a new adsorbent for arsenate [26], fluoride [27], and phosphate removal [28] with high adsorption capacity [29, 30]. But the high cost of Ce limits its use. Therefore, a low cost adsorbent with high adsorption capacities of arsenic is desirable. Recently, many researchers successfully developed cerium-based bimetal oxide adsorbents, such as Ce-Ti [31, 32] and Fe-Ce [33]. The results indicated a remarkably higher adsorption capacity of As (V) than many reported adsorbents. However, the removal efficiency for As (III) is less than 58%.

In this work, a new Ce-Al-Fe trimetal oxide adsorbent, prepared by mixing iron, cerium, and aluminium oxides, was applied to remove As (III) from water to increase the adsorption capacity. Its adsorption capacity of As (III) was evaluated in comparison with commercial materials. The batch adsorption behaviors are including adsorption kinetics, isotherms, and thermodynamics.

2. Experiments

2.1. Adsorbent Preparation

At room temperature, AlCl3·6H2O, Ce(SO4)2·4H2O (analytical grade, Binzhou Kun Bao Chemical Co., Ltd., China), and FeCl3·6H2O were dissolved with deionized water and the Al/Fe/Ce molar ratio of water is 2 : 1 : 0.2, 1 : 2 : 0.2, 2 : 1 : 0.5, 1 : 2 : 0.5, 2 : 1 : 1.5, and 1 : 2 : 1.5. At 200 rpm, the pH was adjusted to 10 by 6 M NaOH solution. After aging of 12 h, the precipitates were collected and washed using distilled water. Finally, the precipitates were dried at 70°C for 12 h.

2.2. Adsorption Experiments for As (III)

The experiment water was prepared by diluting stock solution containing 1000 mg-As·L−1, which was prepared by dissolving NaAsO2 in deionized water. 2 g·L−1 adsorbent granule was added into the water of 100 mL. The mixture was shaken at 150 rpm and 25°C for a long time. Then, the samples were taken and filtered through a membrane of 0.45-μm, and the residual arsenite was determined on an Atomic Absorption Spectrophotometer (ABS-990, Beijing Purkinje General Instrument, China). In the investigation of adsorption kinetics, the initial arsenic concentrations were 3, 8, and 10 mg·L−1. When As (III) initial concentration varied from 1 to 50 mg·L−1, the adsorption isotherms were studied. All experiments were conducted in three times, and all data were the average value.

The adsorption capacity was presented in where (mg·g−1) and (mg·g−1) are the adsorption capacity at time (min) and at equilibrium and (mg·L−1) and (mg·L−1) are equilibrium and initial As (III) concentration. At time , the concentrations of As (III) (mg·L−1) are . And (g) is the adsorbent granule weight, and (L) is the water volume.

3. Results and Discussion

3.1. Morphology of Ce-Al-Fe Trimetal Oxide Adsorbent

The SEM image of Ce-Al-Fe trimetal oxide adsorbents is shown in Figure 1.

Tiny uniformly distributed pores were present on the surface of Ce-Al-Fe trimetal oxide adsorbent. For adsorption, a large surface area was supported by this porous structure with great potential for the removal of As (III).

3.2. Comparison with Other Commercial Adsorbents

Figure 2 illustrates As (III) adsorption capacity onto the adsorbent with different Al/Fe/Ce molar ratio (2 : 1 : 0.2, 1 : 2 : 0.2, 2 : 1 : 0.5, 1 : 2 : 0.5, 2 : 1 : 1.5, and 1 : 2 : 1.5) and the capacities were compared with commercial adsorbents.

The adsorption capacities of As (III) on activated aluminium oxide (AA) and activated carbon (AC) were 3.75 and 1.84 mg·g−1, respectively. And the responding As (III) removal percent was 37.5% and 18.4%. Regardless of the Al/Fe/Ce molar ratio, Ce-Al-Fe trimetal oxide adsorbents had higher adsorption capacity than that of AA and AC. Particularly, the adsorption capacity of As (III) on Ce-Al-Fe adsorbent with Al/Fe/Ce = 2 : 1 : 0.5 was up to 8.18 mg·g−1 and As (III) removal percent of 82% was achieved.

The adsorption capacity was improved as Ce/(Al + Fe) molar ratio increases from 0.2/3 to 0.5/3, while it decreased as Ce/(Al + Fe) molar ratio further increases to 1.5/3. The maximum adsorption capacity (8.18 mg·g−1) was achieved at Al/Fe/Ce molar ratio of 2 : 1 : 0.5.

3.3. Adsorption Kinetics

At initial As (III) concentration of 3, 8, and 10 mg·L−1, As (III) adsorption kinetics on the adsorbent were shown in Figure 3.

The adsorption capacity presented the same trend of variability at different initial concentration. It can be found that Ce-Al-Fe trimetal oxide adsorbent had a high adsorption rate in the first 7 h and the adsorption equilibrium was reached at 24 h. When contact time increased from 24 h to 48 h, the adsorption capacity for As (III) showed no significant change. The equilibrium adsorption capacities of As (III) were 1.225, 3.273, and 4.097 mg·g−1 when initial As (III) concentrations were 3, 8, and 10 mg·L−1, respectively.

To further understand the rate-controlling step and adsorption behavior of Ce-Al-Fe adsorbent for As (III), the adsorption kinetic data were fitted by the pseudo-second-order and pseudo-first-order models, which are usually expressed as [34]where (mg·g−1) and (mg·g−1) are As (III) adsorption capacity at equilibrium and time t (h), (h−1), and (g·mg−1·h−1) are the rate constants. The adsorption rate (mg·g−1·h−1) can be considered to be the rate as approaches 0.

For the adsorption process, the rate limiting step was studied by the intraparticle diffusion model, which is expressed in [35]where is the intercept and (mg·g−1·h1/2) is the rate constant.

The fitted curves of the three models and the fitting parameters are shown in Figure 4 and Table 1, respectively.


Kinetic modelsParameters (mg·L−1)
3810

Pseudo-first-order (mg·g−1)1.2253.2734.097
(h−1)0.0480.0380.031
(mg·g−1)0.9051.3001.440
0.9290.7670.810

Pseudo-second-order (g·mg−1·h−1)0.5030.1500.171
(mg·g−1)1.2693.3934.214
(mg·g−1·h−1)0.8101.7323.042
0.9990.9990.999

Intraparticle diffusion (mg·g−1·h1/2)0.5261.3322.088
0.0850.1980.358
0.9990.9990.999
(mg·g−1·h1/2)0.3300.8110.829
0.2280.5801.391
0.8850.9480.969
(mg·g−1·h1/2)0.0360.1090.112
0.9922.3463.356
0.8820.9360.881

The high correlation coefficient () and the good agreement between the theoretical adsorption capacity () and the experimental adsorption capacity () indicated that As (III) adsorption on Ce-Al-Fe trimetal oxide adsorbent was fitted well by the pseudo-second-order model. This suggested that the adsorption process might be chemisorption [3638]. The adsorption rate () increased with initial increasing As (III) concentration due to increasing driving force.

As shown in Figure 4(c), the intraparticle diffusion kinetic curves presented three linear stages, indicating that the intraparticle diffusion may be one of the rate-controlling steps. The fitted values of values were not zero, giving an indication of the boundary layer thickness. At different As (III) concentration, the diffusion rate constant presents order of . This result suggested that As (III) was adsorbed quickly onto the exterior surface of Ce-Al-Fe trimetal oxide adsorbent at first. Afterwards, the adsorption on the external surface reached equilibrium and As (III) entered into the adsorbent pores slowly. Then, on the interior surface, As (III) adsorption reached equilibrium.

3.4. Adsorption Isotherm

At 20, 30, and 40°C, As (III) adsorption isotherm was investigated with As (III) concentration of 1, 10, 30, 40, and 50 mg·L−1. Figure 5 presented curves of the adsorption capacity (, mg·g−1) versus As (III) equilibrium concentration (, mg·L−1). The adsorption capacity increased as temperature and As (III) concentrations increase.

In order to express the interaction between the adsorbents and adsorbates, adsorption isothermal models including the Langmuir and Freundlich models were applied to investigate the adsorption process. The Langmuir isotherm model assumed that the solid surface is uniform with a monolayer adsorption and no interactions exist between molecules adsorbed [39]. The Freundlich isotherm model assumes multilayer adsorption on heterogeneous surfaces. The Freundlich and Langmuir isotherm model can be represented by [39, 40]where n and (mg1−1/n·L1/n·g−1) are the adsorption intensity and the constants. (mg·g−1) and b (L·mg−1) are the maximum adsorption amount and the constant related to the binding sites affinity. The results are shown in Figure 6 and Table 2.


Adsorption isotherm modelsParametersTemperature (°C)
203040

Langmuir isotherm (mg·g−1)44.38541.58032.787
(L·mg−1)0.0510.0600.084
0.8400.8560.840

Freundlich isotherm (mg1−1/n·L1/n·g−1)2.0052.1862.427
1.1211.1151.128
0.9990.9960.995

The Freundlich isotherm model well scribed the adsorption process, indicated by the high correlation coefficients ( = 0.999, 0.996, and 0.995, resp.) as compared to the Langmuir isotherm model ( = 0.840, 0.856, and 0.840, resp.). This result suggested that As (III) might be adsorbed on the adsorbent surface in the multilayer coverage. calculated values were between 1.115 and 1.128 at 20, 30, and 40°C, indicating that As (III) was favorably adsorbed by Ce-Al-Fe adsorbent studied.

3.5. Adsorption Thermodynamics

To evaluate the nature of the adsorption, three thermodynamic parameters including entropy change (, kJ·mol−1), enthalpy change (, kJ·mol−1), and standard free energy (, kJ·mol−1), which present the inherent energetic changes, were expressed in [41, 42]where (mg1−1/n·L1/n·g−1) was the Freundlich adsorption equilibrium constant and R (8.314 J·mol−1·K−1) and T (K) are the gas constant and the absolute temperature in Kevin. and can be determined from the intercept and slope of the linear plot of versus . Table 3 listed the thermodynamic parameters.


Temperature (K)Thermodynamic parameters
(kJ mol−1) (kJ mol−1) (J mol−1 K−1)

293.15
303.15
313.15

decreased as temperature increases, which indicated that adsorption process of As (III) is more favorable at higher temperatures [43]. values were negative, which suggested the thermodynamic favorability and spontaneity of As (III) adsorption. The positive values confirmed an endothermic nature of As (III) adsorption on Ce-Al-Fe trimetal oxide adsorbent. In addition, the positive values indicated As (III) adsorption process at the solid/solution interface presented an increasing randomness [44].

4. Conclusions

Ce-Al-Fe adsorbent with tiny uniformly distributed pores has been developed for As (III) removal.

At initial As (III) concentration of 3, 8, and 10 mg·L−1, the maximum adsorption capacities of As (III) were 1.48, 3.73, and 5.12 mg·g−1, respectively. Kinetics of fitting by the pseudo-second-order model with higher than 0.998 suggested that the chemisorption was rate-determining process. The adsorption data of Ce-Al-Fe adsorbent can be expressed well by the Freundlich isotherm with greater than 0.996. The negative , positive , and positive suggested that As (III) adsorption nature was exothermic, spontaneous, and increasing randomness on the interface of water and adsorbent.

The adsorption mechanism can be interpreted as chemisorption with multilayer adsorption of As (III) on the adsorbent surface.

Competing Interests

The authors declare that they have no competing interests.

Acknowledgments

The work was financially supported by the Special Foundation of Shandong Province Financial Department and Environmental Protection Bureau under Grant no. SDZS-2012-SHBT01, Shandong Natural Science Foundation under Grant no. ZR2012EEQ024, and Taishan Scholar Foundation.

References

  1. A. Bhatnagar, W. Hogland, M. Marques, and M. Sillanpää, “An overview of the modification methods of activated carbon for its water treatment applications,” Chemical Engineering Journal, vol. 219, pp. 499–511, 2013. View at: Publisher Site | Google Scholar
  2. D. Chauhan, J. Dwivedi, and N. Sankararamakrishnan, “Novel chitosan/PVA/zerovalent iron biopolymeric nanofibers with enhanced arsenic removal applications,” Environmental Science and Pollution Research, vol. 21, no. 15, pp. 9430–9442, 2014. View at: Publisher Site | Google Scholar
  3. X. Wu, X. Tan, S. Yang et al., “Coexistence of adsorption and coagulation processes of both arsenate and NOM from contaminated groundwater by nanocrystallined Mg/Al layered double hydroxides,” Water Research, vol. 47, no. 12, pp. 4159–4168, 2013. View at: Publisher Site | Google Scholar
  4. M. Kobya, E. Demirbas, U. Gebologlu, M. S. Oncel, and Y. Yildirim, “Optimization of arsenic removal from drinking water by electrocoagulation batch process using response surface methodology,” Desalination and Water Treatment, vol. 51, no. 34–36, pp. 6676–6687, 2013. View at: Publisher Site | Google Scholar
  5. A. K. Meher, S. Das, S. Rayalu, and A. Bansiwal, “Enhanced arsenic removal from drinking water by iron-enriched aluminosilicate adsorbent prepared from fly ash,” Desalination and Water Treatment, 2015. View at: Publisher Site | Google Scholar
  6. M. C. S. Faria, R. S. Rosemberg, C. A. Bomfeti et al., “Arsenic removal from contaminated water by ultrafine δ-FeOOH adsorbents,” Chemical Engineering Journal, vol. 237, pp. 47–54, 2014. View at: Publisher Site | Google Scholar
  7. M.-L. Chen, Y. Sun, C.-B. Huo, C. Liu, and J.-H. Wang, “Akaganeite decorated graphene oxide composite for arsenic adsorption/removal and its proconcentration at ultra-trace level,” Chemosphere, vol. 130, pp. 52–58, 2015. View at: Publisher Site | Google Scholar
  8. M. Mosaferi, S. Nemati, A. Khataee, S. Nasseri, and A. A. Hashemi, “Removal of arsenic (III, V) from aqueous solution by nanoscale zero-valent iron stabilized with starch and carboxymethyl cellulose,” Journal of Environmental Health Science and Engineering, vol. 12, no. 1, article 74, 2014. View at: Publisher Site | Google Scholar
  9. M. Rahim and M. R. H. M. Haris, “Application of biopolymer composites in arsenic removal from aqueous medium: a review,” Journal of Radiation Research and Applied Sciences, vol. 8, no. 2, pp. 255–263, 2015. View at: Publisher Site | Google Scholar
  10. Y.-J. Shih, R.-L. Huang, and Y.-H. Huang, “Adsorptive removal of arsenic using a novel akhtenskite coated waste goethite,” Journal of Cleaner Production, vol. 87, no. 1, pp. 897–905, 2015. View at: Publisher Site | Google Scholar
  11. J. Li, Y.-N. Wu, Z. Li et al., “Zeolitic imidazolate framework-8 with high efficiency in trace arsenate adsorption and removal from water,” The Journal of Physical Chemistry C, vol. 118, no. 47, pp. 27382–27387, 2014. View at: Publisher Site | Google Scholar
  12. S. Bordoloi, S. K. Nath, S. Gogoi, and R. K. Dutta, “Arsenic and iron removal from groundwater by oxidation-coagulation at optimized pH: laboratory and field studies,” Journal of Hazardous Materials, vol. 260, pp. 618–626, 2013. View at: Publisher Site | Google Scholar
  13. A. Dominguez-Ramos, K. Chavan, V. García et al., “Arsenic removal from natural waters by adsorption or ion exchange: an environmental sustainability assessment,” Industrial & Engineering Chemistry Research, vol. 53, no. 49, pp. 18920–18927, 2014. View at: Publisher Site | Google Scholar
  14. T. A. Vu, G. H. Le, C. D. Dao et al., “Arsenic removal from aqueous solutions by adsorption using novel MIL-53(Fe) as a highly efficient adsorbent,” RSC Advances, vol. 5, no. 7, pp. 5261–5268, 2015. View at: Publisher Site | Google Scholar
  15. Y.-S. Han, A. H. Demond, T. J. Gallegos, and K. F. Hayes, “Dependence of particle concentration effect on pH and redox for arsenic removal by FeS-coated sand under anoxic conditions,” Chemosphere, vol. 134, pp. 499–503, 2015. View at: Publisher Site | Google Scholar
  16. J. V. Flores-Cano, R. Leyva-Ramos, F. Carrasco-Marin, A. Aragón-Piña, J. J. Salazar-Rabago, and S. Leyva-Ramos, “Adsorption mechanism of Chromium(III) from water solution on bone char: effect of operating conditions,” Adsorption, vol. 22, no. 3, pp. 297–308, 2016. View at: Publisher Site | Google Scholar
  17. A. D. Abid, M. Kanematsu, T. M. Young, and I. M. Kennedy, “Arsenic removal from water using flame-synthesized iron oxide nanoparticles with variable oxidation states,” Aerosol Science and Technology, vol. 47, no. 2, pp. 169–176, 2013. View at: Publisher Site | Google Scholar
  18. M. R. Lescano, C. Passaliá, C. S. Zalazar, and R. J. Brandi, “Arsenic sorption onto titanium dioxide, granular ferric hydroxide and activated alumina: batch and dynamic studies,” Journal of Environmental Science and Health, Part A: Toxic/Hazardous Substances and Environmental Engineering, vol. 50, no. 4, pp. 424–431, 2015. View at: Publisher Site | Google Scholar
  19. T. Mishra and D. K. Mahato, “A comparative study on enhanced arsenic(V) and arsenic(III) removal by iron oxide and manganese oxide pillared clays from ground water,” Journal of Environmental Chemical Engineering, vol. 4, no. 1, pp. 1224–1230, 2016. View at: Publisher Site | Google Scholar
  20. T. Wen, X. Wu, X. Tan, X. Wang, and A. Xu, “One-pot synthesis of water-swellable Mg–Al layered double hydroxides and graphene oxide nanocomposites for efficient removal of As(V) from aqueous solutions,” ACS Applied Materials and Interfaces, vol. 5, no. 8, pp. 3304–3311, 2013. View at: Publisher Site | Google Scholar
  21. S. Liu, S. Kang, G. Wang, H. Zhao, and W. Cai, “Micro/nanostructured porous Fe-Ni binary oxide and its enhanced arsenic adsorption performances,” Journal of Colloid and Interface Science, vol. 458, pp. 94–102, 2015. View at: Publisher Site | Google Scholar
  22. G. Zhang, Z. Ren, X. Zhang, and J. Chen, “Nanostructured iron (III)-copper (II) binary oxide: a novel adsorbent for enhanced arsenic removal from aqueous solutions,” Water Research, vol. 47, no. 12, pp. 4022–4031, 2013. View at: Publisher Site | Google Scholar
  23. K.-H. Goh, T.-T. Lim, and Z. Dong, “Enhanced arsenic removal by hydrothermally treated nanocrystalline MG/AL layered double hydroxide with nitrate intercalation,” Environmental Science & Technology, vol. 43, no. 7, pp. 2537–2543, 2009. View at: Publisher Site | Google Scholar
  24. J. A. Muñoz, A. Gonzalo, and M. Valiente, “Arsenic adsorption by Fe(III)-loaded open-celled cellulose sponge. Thermodynamic and selectivity aspects,” Environmental Science & Technology, vol. 36, no. 15, pp. 3405–3411, 2002. View at: Publisher Site | Google Scholar
  25. I. Akin, G. Arslan, A. Tor, Y. Cengeloglu, and M. Ersoz, “Removal of arsenate [As(V)] and arsenite [As(III)] from water by SWHR and BW-30 reverse osmosis,” Desalination, vol. 281, pp. 88–92, 2011. View at: Publisher Site | Google Scholar
  26. L. Yu, Y. Ma, C. N. Ong, J. Xie, and Y. Liu, “Rapid adsorption removal of arsenate by hydrous cerium oxide-graphene composite,” RSC Advances, vol. 5, no. 80, pp. 64983–64990, 2015. View at: Publisher Site | Google Scholar
  27. D. Tang and G. Zhang, “Efficient removal of fluoride by hierarchical Ce-Fe bimetal oxides adsorbent: thermodynamics, kinetics and mechanism,” Chemical Engineering Journal, vol. 283, pp. 721–729, 2016. View at: Publisher Site | Google Scholar
  28. Y. Su, W. Yang, W. Sun, Q. Li, and J. K. Shang, “Synthesis of mesoporous cerium-zirconium binary oxide nanoadsorbents by a solvothermal process and their effective adsorption of phosphate from water,” Chemical Engineering Journal, vol. 268, pp. 270–279, 2015. View at: Publisher Site | Google Scholar
  29. T. Parangi, B. Wani, and U. Chudasama, “Sorption and separation study of heavy metal ions using cerium phosphate: a cation exchanger,” Desalination and Water Treatment, vol. 57, no. 14, pp. 6443–6451, 2016. View at: Publisher Site | Google Scholar
  30. V. Kuroki, G. E. Bosco, P. S. Fadini, A. A. Mozeto, A. R. Cestari, and W. A. Carvalho, “Use of a La(III)-modified bentonite for effective phosphate removal from aqueous media,” Journal of Hazardous Materials, vol. 274, pp. 124–131, 2014. View at: Publisher Site | Google Scholar
  31. G. K. Reddy, J. He, S. W. Thiel, N. G. Pinto, and P. G. Smirniotis, “Sulfur-tolerant Mn-Ce-Ti sorbents for elemental mercury removal from flue gas: mechanistic investigation by XPS,” Journal of Physical Chemistry C, vol. 119, no. 16, pp. 8634–8644, 2015. View at: Publisher Site | Google Scholar
  32. Y. Li, X. Cai, J. Guo, S. Zhou, and P. Na, “Fe/Ti co-pillared clay for enhanced arsenite removal and photo oxidation under UV irradiation,” Applied Surface Science, vol. 324, pp. 179–187, 2015. View at: Publisher Site | Google Scholar
  33. B. Chen, Z. Zhu, Y. Guo, Y. Qiu, and J. Zhao, “Facile synthesis of mesoporous Ce-Fe bimetal oxide and its enhanced adsorption of arsenate from aqueous solutions,” Journal of Colloid and Interface Science, vol. 398, pp. 142–151, 2013. View at: Publisher Site | Google Scholar
  34. Y. S. Ho and G. McKay, “Kinetic models for the sorption of dye from aqueous solution by wood,” Process Safety and Environmental Protection, vol. 76, no. 2, pp. 183–191, 1998. View at: Publisher Site | Google Scholar
  35. G. H. Graaf, H. Scholtens, E. J. Stamhuis, and A. A. C. M. Beenackers, “Intra-particle diffusion limitations in low-pressure methanol synthesis,” Chemical Engineering Science, vol. 45, no. 4, pp. 773–783, 1990. View at: Publisher Site | Google Scholar
  36. P. Ilgin and A. Gur, “Synthesis and characterization of a new fast swelling poly(EPMA-co-METAC) as superabsorbent polymer for anionic dye absorbent,” Iranian Polymer Journal, vol. 24, no. 2, pp. 149–159, 2015. View at: Publisher Site | Google Scholar
  37. H. H. Najafabadi, M. Irani, L. Roshanfekr Rad, A. Heydari Haratameh, and I. Haririan, “Removal of Cu2+, Pb2+ and Cr6+ from aqueous solutions using a chitosan/graphene oxide composite nanofibrous adsorbent,” RSC Advances, vol. 5, no. 21, pp. 16532–16539, 2015. View at: Publisher Site | Google Scholar
  38. F. Luo, J. L. Chen, L. L. Dang et al., “High-performance Hg2+ removal from ultra-low-concentration aqueous solution using both acylamide- and hydroxyl-functionalized metal-organic framework,” Journal of Materials Chemistry A, vol. 3, no. 18, pp. 9616–9620, 2015. View at: Publisher Site | Google Scholar
  39. I. Langmuir, “The adsorption of gases on plane surfaces of glass, mica and platinum,” Journal of the American Chemical Society, vol. 40, no. 9, pp. 1361–1403, 1918. View at: Publisher Site | Google Scholar
  40. H. Freundlich, “Over the adsorption in solution,” The Journal of Physical Chemistry, vol. 57, no. 385, pp. 462–470, 1906. View at: Google Scholar
  41. C. Santhosh, P. Kollu, S. Felix, V. Velmurugan, S. K. Jeong, and A. N. Grace, “CoFe2O4 and NiFe2O4@graphene adsorbents for heavy metal ions-kinetic and thermodynamic analysis,” RSC Advances, vol. 5, no. 37, pp. 28965–28972, 2015. View at: Publisher Site | Google Scholar
  42. W.-T. Jiang, P.-H. Chang, Y. Tsai, and Z. Li, “Halloysite nanotubes as a carrier for the uptake of selected pharmaceuticals,” Microporous and Mesoporous Materials, vol. 220, pp. 298–307, 2016. View at: Publisher Site | Google Scholar
  43. M. R. Yazdani, T. Tuutijärvi, A. Bhatnagar, and R. Vahala, “Adsorptive removal of arsenic(V) from aqueous phase by feldspars: kinetics, mechanism, and thermodynamic aspects of adsorption,” Journal of Molecular Liquids, vol. 214, pp. 149–156, 2016. View at: Publisher Site | Google Scholar
  44. L. J. Kennedy, J. J. Vijaya, G. Sekaran, and K. Kayalvizhi, “Equilibrium, kinetic and thermodynamic studies on the adsorption of m-cresol onto micro- and mesoporous carbon,” Journal of Hazardous Materials, vol. 149, no. 1, pp. 134–143, 2007. View at: Publisher Site | Google Scholar

Copyright © 2016 Cuizhen Sun et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


More related articles

1054 Views | 556 Downloads | 3 Citations
 PDF  Download Citation  Citation
 Download other formatsMore
 Order printed copiesOrder

Related articles

We are committed to sharing findings related to COVID-19 as quickly and safely as possible. Any author submitting a COVID-19 paper should notify us at help@hindawi.com to ensure their research is fast-tracked and made available on a preprint server as soon as possible. We will be providing unlimited waivers of publication charges for accepted articles related to COVID-19. Sign up here as a reviewer to help fast-track new submissions.