Desorption of 1-butanol from polymeric resin: Experimental studies and mathematical modeling

Desorption is essential to design an integrated recovery process for 1-butanol, a potential biofuel. The modeling of desorption processes is a significant tool to optimize the separation process of 1-butanol. In this work, we systematically studied the desorption of 1-butanol from a porous polymeric resin KA-I by solvent desorption technique. The desorption equilibrium, desorption kinetics and dynamic desorption behaviors were studied experimentally and simulated theoretically. About 1.5 bed volumes of absolute ethanol could desorb 1-butanol completely with 73.6 g L^-1 1-butanol in the effluent in the fixed bed system. A pore diffusion model was used to fit the desorption kinetics of 1-butanol satisfactorily. The concentration evolution of eluent and 1-butanol in the resin pore was simulated. During desorption, the concentration of 1-butanol in the resin pore increases gradually at first, and then decreases gradually due to the slower pore diffusion. Moreover, a general rate model was used to predict the dynamic desorption profiles of 1-butanol under different operating conditions successfully. Finally, repeated adsorption and desorption dynamic cycles were predicted by the general rate model quite well.