Kinetic and equilibrium adsorption parameters estimation based on a heterogeneous intraparticle diffusion model

In this work, a commercial resin with well-developed internal pore structure was chosen to adsorb four parabens used as probe molecules. The main novelty propose and validate phenomenological transient adsorption model based on conservation law in both phases coupled Langmuir’s equilibrium Fick’s mass transfer rate inside the pores. With such an aim, heterogeneous three-parameter intraparticle diffusion model, IPDM, formulated, its numerical solution fitted time-dependent concentration data by minimizing sum of squared residuals. Equilibrium constants were also predicted fitting Langmuir isotherm data. A monolayer capacity 0.81 mmol/g calculated for regardless number carbons ester group. optimal parameters values from IPDM process, system ODEs comprising local sensitivity coefficients dependent variables solved compute parameters’ variance-covariance matrix infer their ranges 95% marginal confidence interval. order test validity proposed attempt crosscheck between obtained estimation related parameter, κ, modified ξp′, ones carried out. As far concern, there is relative agreement limits range estimated amount adsorbed initial bulk concentration, q0, constant, K, adjusted kinetic data, independently. Additionally, magnitude diffusivity work accordance one Wilke-Chang correlation inversely proportional van der Waals volume raised power 0.53 close literature.