Study of mass transfer parameters and identification of rate-controlling step in the cerium and yttrium ion exchange process in a fixed bed column

Ildarabadi, Amin; Khajenoori, Maryam; Zahakifar, Fazel; Ghadiri, Ahmad

doi:10.24200/nst.2025.1797.2108

Study of mass transfer parameters and identification of rate-controlling step in the cerium and yttrium ion exchange process in a fixed bed column

Articles in Press

Document Type : Research Paper

Authors

Amin Ildarabadi ¹

Maryam Khajenoori ¹

Fazel Zahakifar ²

Ahmad Ghadiri ³

¹ Faculty of Chemical, Petroleum and Gas Engineering, Semnan University, P.O.Box: 35131-19111, Semnan – Iran

² Nuclear Fuel Cycle Research School, Nuclear Science and Technology Research Institute

³ Nuclear Fuel Cycle Research School, Nuclear Science and Technology Research Institute, AEOI, P.O.Box: 11365-8486, Tehran – Iran

https://doi.org/10.24200/nst.2025.1797.2108

Abstract

In this study, the ion exchange process of cerium and yttrium using Dowex 50W-X8 resin was investigated and the behavior of the breakthrough curves were reported. The ion exchange percentage for Ce(III) and Y(III) was 73.93% and 70%, respectively. Mathematical modeling was performed to calculate the mass transfer components. Various mass transfer resistance mechanisms such as film diffusion resistance, intraparticle diffusion and axial dispersion as well as other mass transfer approximations were investigated by the linear driving force (LDF) model. Investigations showed that intraparticle diffusion resistance had the largest contribution in the ion exchange process of rare elements cerium and yttrium (R_f<R_ax<R_int). Intraparticle diffusion, i.e. the second stage of the overall ion exchange mechanism, was identified as the controlling stage of the process. Also, the Biot number for Ce(III) and Y(III) was greater than 30, indicating that the rate-controlling step of the ion exchange process was intraparticle diffusion. Thus, the accuracy of the studies was confirmed. The Peclet number also matched the slope of the breakthrough curves well.

Keywords

Ion exchange

Cerium

Yttrium

Fixed bed column

Mass transfer resistance

Main Subjects