U(VI) İyonlarının Ham ve Modifiye Edilmiş Diyatomit Üzerine Adsorpsiyon Özelliklerinin Kinetik ve Termodinamik Olarak İncelenmesi

Öz

Bu çalışmada, giderimi ham ve asit ile modifiye edilmiş diyatomit kullanılarak uranyumun sulu çözeltilerden uzaklaştırılabilirliği araştırılmıştır. Adsorban olarak kullanılan ham ve asit modifiyeli diyatomit örneklerinin karakterizasyonu için SEM, XRD ve TGA/ DTA analiz teknikleri kullanılmıştır. Adsorpsiyon kinetiğinin incelenmesi için üç farklı konsantrasyon ile çalışılmıştır. Elde edilen verilere göre hem ham, hem de asit modifiyeli diyatomit adsorbanı üzerine uranyum iyonlarının adsorpsiyon prosesinin yalancı II. mertebe üzerinden kimyasal adsorpsiyon ile gerçekleştiği görülmüştür. Ayrıca adsorpsiyona sıcaklığın etkisi incelenmiş ve termodinamik parametreler hesaplanmıştır. Her iki adsorban içinde hesaplanan pozitif entalpi, adsorpsiyon prosesinin endotermik olduğunu göstermiştir. Bununla birlikte yine her iki adsorban içinde negatif serbest enerji değişimi, adsorpsiyon prosesinin çalışılan sıcaklıklarda kendiliğinden gerçekleştiğini göstermiştir. Entropinin pozitif değerleri ise, adsorpsiyon prosesi sırasında katı/çözelti ara yüzeyindeki gelişi güzel tutunmanın arttığını göstermiştir.

Anahtar Kelimeler

• Adsorpsiyon,Diyatomit,Kinetik parametreler,Termodinamik parametreler

Investigation of the Kinetic and Thermodynamic Properties of U(VI) Ions onto Raw and Modified Diatomite

Öz

In this study, the removal of uranium from aqueous solutions by natural and modified diatomite has been investigated. SEM, XRD and TGA/DTA analysis techniques were used for the characterization of natural and acid modified diatomite samples as adsorbents. The adsorption process was examined kinetically according to obtained data from adsorption studies at three different concentrations, and it was found adsorption process was best described by the pseudo-second-order model with chemical adsorption. The effect of temperature on the adsorption was also examined and thermodynamic parameters were calculated. Positive enthalpy calculated for both adsorbents have shown that the adsorption process is endothermic. In addition negative values of free energy change indicated the spontaneity of the adsorption at the studied temperatures. The positive values of entropy show the increasing randomness at the solid/solution interface during the adsorption process.

Anahtar Kelimeler

• Adsorption,Diatomite,Kinetic parameters,Thermodynamic parameters

Kaynakça

1. 1. Veglio, F, Beolchini, F, Removal of metals by biosorption: a review, Hydrometallurgy, 1997, 44, 301-316.
2. 2. Volesky, B, Biosorption of Heavy Metals, CRC Press, Florida, 1990; pp 396.
3. 3. Wase, J, Forster, C, Biosorbents for Metal Ions, Taylor&Francis Ltd., London, 1997; pp 238.
4. 4. Toxicological profile for uranium. U.S. Department of Health and Human Services, Agency for Toxic Substances and Disease Registry. http://www.atsdr.cdc.gov/toxprofiles/tp150.pdf/, 2011 (accessed 25.10.2016).
5. 5. Lawrence, D.G, Uranium toxicity literature with commentaries, Department of Chemistry and Biochemistry, Long Island University, Brooklyn, 2004.
6. 6. Nilchi, A, Dehaghan, T.S, Garmarodi, S.R, Kinetics, isotherm and thermodynamics for uranium and thorium ions adsorption from aqueous solutions by crystalline tin oxide nanoparticles, Desalination, 2013, 321, 67–71.
7. 7. Bampaiti, A, Misaelides, P, Noli, F, Uranium removal from aqueous solutions using a raw and HDTMA-modified phillipsite-bearing tuff, Journal of Radioanalytical and Nuclear Chemistry, 2015, 303(3), 2233–2241.
8. 8. Hoshikawa, T, Kawamura, F, Sawaa, T, Suzuoki, A, Kumagai, M, Takashima, Y, Asou, M, Namba, T, Kinumaki, H, Ohe, S, A new concept of nuclear fuel reprocessing by applying ion-exchange technology, Progress in Nuclear Energy, 1998, 32(3-4), 365-371.

9. 9. Slater, S.A, Raraz, A.G, Willit, J.L, Gay, E.C, Electrochemical separation of aluminum from uranium for research reactor spent nuclear fuel applications, Separation and Purification Technology, 1999, 15(3), 197-205.
10. 10. [Mellah, A, Chegrouche, S, Barkat, M, The removal of uranium (VI) from aqueous solutions onto activated carbon: kinetic and thermodynamic investigations, Journal of Colloid and Interface Science, 2006, 296, 434-441.
11. 11. Deliyanni, E.A, Bakoyannakis, D.N, Zouboulis, A.I, Matis, K.A, Sorption of As(V) ions by akaganeite-type nanocrystals, Chemosphere, 2003, 50, 155–163.
12. 12. Aytas, O.S, Akyil, S, Aslani, M.A.A, Aytekin, U, Removal of uranium from aqueous solutions by diatomite (Kieselguhr), Journal of Radioanalytical and Nuclear Chemistry, 1999, 240 (3), 973-976.
13. 13. Yusan, S, Gok, C, Erenturk, S, Aytas, S, Adsorptive removal of thorium (IV) using calcined and flux calcined diatomite from Turkey: Evaluation of equilibrium, kinetic and thermodynamic data, Applied Clay Science, 2012, 67–68, 106–116.
14. 14. Sprynskyy, M, Kovalchuk, I, Buszewski, B, The separation of uranium ions by natural and modified diatomite from aqueous solution, Journal of Hazardous Materials, 2010, 181(1-3), 700-707.
15. 15. Galal, H.E, Bakr, M.M, Diatomite: Its Characterization, Modifications and Applications, Asian Journal of Material Science, 2010, 2(3), 121-136.
16. 16. Mohamedbakr, H, Burkitbaev, M, Immobilization of lead ion from aqueous solutions by using natural/processed diatomite, Oecologia Aegyptiaca, 2008, 1, 21-29.
17. 17. Bailey, S.E, Olin, T.J, Bricka R.M, Adrian, D.D, A review of potentially low-cost sorbents for heavy metals, Water Research, 1999, 33, 2469-2479.
18. 18. Chang, F, Qu, J, Liu, H, Liu, R, Zhao, X, Fe–Mn binary oxide incorporated into diatomite as an adsorbent for arseniteremoval: Preparation and evaluation, Journal of Colloid and Interface Science, 2009, 338, 353-358.
19. 19. Bakr, H.E.G.M. M, Diatomite: Its Characterization, Modifications and Applications, Asian Journal of Material Science, 2010, 2(3), 121-136.
20. 20. Yuan, P, Liu, D, Fan, M, Yang, D, Zhu, R, Ge, F, Zhu, J, He, H, Removal of hexavalent chromium [Cr(VI)] from aqueous solutions by the diatomite-supported/unsupported magnetite nanoparticles, Journal of Hazardous Materials, 2010, 173, 614–621.
21. 21. Florence, T.M, AAEC/TM552, Paper 5, 1970.
22. 22. Francois, C.A, Rapid spectrophotometric determination of submilligram quantities of uranium, Analytical Chemistry, 1958, 30, 50–54.
23. 23. Bağci, C, Microstructural characterisation of β-SiC powders synthesised by carbothermally reduction of Turkish diatomite, Scientific Research and Essays, 2011, 6, 542–551.
24. 24. Chaisena, A, Rangsriwatananon, K, Effects of thermal and acid treatments on some physico-chemical properties of lampang diatomites, Suranaree Journal of Science and Technology, 2004, 11, 289–299.
25. 25. Chen, Y, Xiao, M, Wang, S, Han, D, Lu, Y, Meng, Y, Porous diatomiteimmobilized Cu–Ni bimetallic nanocatalysts for direct synthesis of dimethyl carbonate, Journal of Nanomaterials, 2012, 1–8 (Article ID 610410).
26. 26. Du, Y.C, Shia, S.L, Bu, C.Y, Dai, H.X, Guo, Z.G, Tang, G.Y, Effect of particle size distribution of calcined diatomites on the extinction performance, Particulate Science and Technology, 2011, 29, 368–377.
27. 27. Zhu, Q, Zhanga, Y, Zhou, F, Lv, F, Ye, Z, Fan, F, Chu, P.K, Preparation and characterization of Cu2O–ZnO immobilized on diatomite for photocatalytic treatment of red water produced from manufacturing of TNT, Chemical Engineering Journal, 2011, 171, 61–68.
28. 28. Neves, G.M, Lenza, R.F.S, Vasconcelos, W.L, Evaluation of the Influence of Microwaves in the Structure of Silica Gels, Material Research, 2002, 5, 447–451.
29. 29. Han, R, Zou, W, Wang, Y, Zhu, L, Removal of uranium (VI) fromaqueous solutions by manganese oxide coated zeolite: discussion of adsorption isotherms and pH effect, Journal of Environmental Radioactivity, 2007, 93, 127–143.
30. 30. Sorg, T.J, Removal of Uranium from Drinking Water by Conventional Treatment Methods. In: Cothern C.R. and Rebers P.A. (ed) Radon, Radium and Uranium in Drinking Water, Lewis Publishers, Inc., MI, 1991, pp 97.
31. 31. Memon, J.R.; Hallam, K.R.; Bhanger, M.I.; El-Turki, A.; Allen, G.C. Evaluation of sorption of uranium onto metakaolin using X-ray photoelectron and Raman spectroscopies, Analytical Chimica Acta, 2009, 631, 69–73.
32. 32. Anirudhan, T.S, Divya, L, Suchithra, P.S, Kinetic and equilibrium characterization of uranium(VI) adsorption onto carboxylate-functionalized poly(hydroxyethylmethacrylate)- grafted lignocellulosics, Journal of Environmental Management, 2009, 90, 549-560.
33. 33. Hameed, B.H, Salman, J.M, Ahmad, A.L, Adsorption isotherm and kinetic modeling of 2,4-D pesticide on activated carbon derived from date Stones, Journal of Hazardous Materials, 2009, 163, 121–126.
34. 34. Ijagbemi, O.C, Baek, M, Kim, D, Montmorillonite surface properties and sorption characteristics for heavy metal removal from aqueous solutions, Journal of Hazardous Materials, 2009, 166, 538–546.
35. 35. Annadurai, G, Ling, L.Y, Lee, J.F, Adsorption of reactive dye from an aqueous solution by chitosan: isotherm, kinetic and thermodynamic analysis, Journal of Hazardous Materials, 2008, 152, 337-346.
36. 36. Ozacar, M, Sengil, I.A, Adsorption of reactive dyes on calcined alunite from aqueous solutions, Journal of Hazardous Materials, 2003, 98, 211-224.
37. 37. Meena, A.K, Mishra, G.K, Rai, P.K, Rajagopal, C, Nagar, P.N, Removal of heavy meal ions from aqueous solutions using carbon aeogel as an adsorbent, Journal of Hazardous Materials, 2005, 122, 161–170.
38. 38. Yavuz, O, Altunkaynak, Y, Guzel, F, Removal of copper, nickel, cobalt and manganese from aqueous solution by kaolinite, Water Research, 2003, 37, 948–952.
39. 39. Jain, C.K, Singhal, D.C, Sharma, M.K, Adsorption of zinc on bed sediment of River Hindon: adsorption models and kinetics, Journal of Hazardous Materials, 2004, B114, 231–239.
40. 40. Smith, J.M, Chemical Engineering Kinetics, 3rd edn. McGraw-Hill, New York, 1981; pp. 310-322.