Recovery of acetate by anion exchange with consecutive CO2-expanded methanol desorption: A model-based approach

Abstract

Production of bio-based acetate is commonly hindered by the high costs of the downstream processing. In this paper, a model is developed to describe a new method that recovers acetate salts using anion exchange resins, and subsequently desorbs and upgrades them using CO2-expanded alcohol. The model consists of equilibrium parameters for both the adsorption and desorption step. The calculated parameters are: for the adsorption − =− KCl 0.125 Ac , − = − K 0.206 Cl HCO3 and KOV HAc , = 0.674 mol / kgresin mol / kgsolution , and for the desorption − = − pK 3.71. MeCO Ac 3 The maximum experimental concentration of acetic acid obtained in CO2-expanded methanol is 0.427 mol/kg (20 g/ LMeOH) at an operating pressure of 31 bar. The model represents the expected trends for all species, and can be used to design a multicolumn system for the recovery and upgrading of carboxylates