Dynamic Studies of Binary Adsorption System in Fixed Beds using Orthogonal Collocation on Finite Element Method

In this study, a generalized, comprehensive and feasible mathematical model was developed for the description of the adsorption of multicomponent system in a fixed bed containing solid adsorbent. It took into cognizance of all the factors considered negligible in the literature, which included intraparticle, interparticle and interphase diffusional resistances, conditions of non-equilibrium and non-linear binary adsorption of butan-2-ol and 2-methylbutan-2-ol onto the adsorbent Filtrasorb 400 (granular activated carbon). The resulting 4N hyperbolic and parabolic differential equations were numerically solved using orthogonal collocation on finite element method. Excellent agreements were achieved between the experimental data and the simulated results of breakthrough times and concentrations of the solutes in fixed beds of 0.41, 0.82 and 1.23 m. Equally, the observed chromatographic tops of the less strongly adsorbed component (butan-2-ol) and the effects of adsorber length on times of breakthrough of the components and height of peaks were precisely simulated. The results of this study are of beneficial use in the design and analysis of fixed beds employed for the treatment of multicomponent aqueous wastewater effluents from industry.