Theoretical and experimental studies of benzoic acid batch adsorption dynamics using vermiculite-based adsorbent

•Modification of raw vermiculite both mechanically and organically.•An improved performance of the modified vermiculite for benzoic acid adsorption.•Excellent fitting of the experimental data with the Freundlich and the Toth models.•Development of a pore diffusion-based model to study the adsorption dynamics.•Estimation of the effective diffusivity of benzoic acid as 0.33×10−9m2s−1.