A simplified technique to determine intraparticle diffusivity of macro-reticular resins

Both resins and activated carbons are commonly used as adsorbents in water and wastewater treatment. In general, intraparticle diffusion mechanisms within macro reticular resin particles (such as XAD-2000) are different from those in activated carbon particles. Currently, completely mixed batch reactor (CMBR) technique can be used to determine the intraparticle diffusivity for phenolic compounds adsorbed onto activated carbon systems. However, the technology cannot determine the intraparticle diffusivity accurately if the fluid-film resistance is significant, such as synthetic macro-reticular resins. Therefore, this study develops a technique to determine the intraparticle diffusivities of XAD-2000 resin. This paper characterized the concentration decay curves of para-nitrophenol in CMBR to determine effective pore diffusivity (DP) of the resin. The obtained mean and standard deviation of DP are about 1.1 × 10−5 and 3.2 × 10−6 (cm2 s−1), respectively. The technology developed in this study has the advantages of significant chemical saving and easy operation. [Display omitted] •A simplified technique is developed to determine the intraparticle diffusivity of macro reticular resins.•The CMBR technique can be applied in low Biot number (Bi) conditions.•The method has advantages of chemicals saving and easy to do experiments.