Experimental Study on the Liquid-Phase Adsorption Equilibrium of n-Butanol over Amberlyst TM15 and Contribution of Diffusion Resistances

Abstract

This work investigates the liquid-phase adsorption of n-butanol on Amberlyst 15 in the temperature range 295-323 K at different initial adsorbate concentrations. The adsorbent was characterized by N2 physisorption, Fourier transform infrared adsorption of pyridine, scanning electron microscopy, and powder X-ray diffraction. The data obtained confirmed an adsorbent structure with two porosity levels and amorphous polymer structure. The active sites in Amberlyst 15 are of Brønsted or Brønsted-Lewis type. The liquid-phase adsorption equilibrium constants were determined at different temperatures from slurry adsorber experiments. The thermodynamic state functions were estimated and are consistent thermodynamically with physical adsorption. The macropore diffusion coefficients of n-butanol on Amberlyst 15 were estimated by using the moment technique, and the contribution of surface diffusion to the macropore diffusion coefficients was evaluated.