Maxwell–Stefan based modelling of ion exchange systems containing common species (Cd2+, Na+) and distinct sorbents (ETS-4, ETS-10)
- 199 Downloads
Cadmium(II) is a toxic hazardous cation, whose presence in the environment causes great concern because of its bioaccumulation in organisms and bioamplification along food chain. Hence, the removal of cadmium compounds from industrial waters and wastewaters is particularly essential, which requires intensive experimental and modelling studies to deal with the problem. In this work, the ion exchange of Cd2+ ions from aqueous solution using microporous titanosilicates (ETS-4 and ETS-10) has been modelled using adapted Maxwell–Stefan equations for the ions transport inside the sorbent particles. The fundamentals of the Maxwell–Stefan equations along with correlations for the convective mass transfer coefficients have been used with advantage to reduce the number of model parameters. In the whole, the model was able to represent successfully the kinetic behaviour of 11 independent and very distinct curves of both studied systems (Cd2+/Na+/ETS-4 and Cd2+/Na+/ETS-10). The predictive capability of the model has been also shown, since several uptake curves were accurately predicted with parameters fitted previously to different sets of experimental data.
KeywordsCadmium(II) ETS-4 ETS-10 Ion exchange Maxwell–Stefan Modelling
Patrícia F. Lito wishes to thank Fundação para a Ciência e Tecnologia (Portugal) for the Grant (SFRH/BPD/63214/2009) provided for this study.
- Clark RB, Frid C, Attrill M (2001) Marine pollution. Oxford press, OxfordGoogle Scholar
- Helfferich F (1995) Ion exchange. Dover, New YorkGoogle Scholar
- Jackson R (1977) Transport in porous catalysts. Elsevier, AmsterdamGoogle Scholar
- Lito PF, Silva CM (2008) Comparison between Maxwell–Stefan and Nernst–Planck equations to describe ion exchange in microporous materials. Defect Diffus Forum 273–276:776–781Google Scholar
- Lito PF, Cardoso SP, Loureiro JM, Silva CM (2012). Ion-exchange equlibria and kinetics. In: Inamuddin S, Luqman M (eds) Ion-exchange technology: theory, materials and applications, chap 3, pp 51–120. Springer, BerlinGoogle Scholar
- Miller SA, Amber CM, Bennet RC, Dahlstrom DA, Darji JD, Emmet RC, Gray JB, Gurnham CF, Jacobs LJ, Klepper RP, Michalson AW, Oldshue JY, Silverblatt CE, Smith JC, Todd DB (1984) Liquid–solid systems. In: Perry RH, Green D (eds) Perry’s chemical engineers’ handbook. McGrow-Hill, SingaporeGoogle Scholar
- Økland TE, Wilhelmsen E, Solevåg Ø (2005) A study of the priority substances of the Water Framework Directive, monitoring and need for screening. Bergfald & Co., NorwayGoogle Scholar
- Schiesser WE (1991) The numerical method of lines. Academic Press, USAGoogle Scholar
- Slater MJ (1991) Principles of ion exchange technology. Butterworth-Heinemann, Great BritainGoogle Scholar
- Treybal RE (1981) Mass-transfer operations. McGraw-Hill International Editions, SingaporeGoogle Scholar