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- Ac- =0.125, KCl- HCO3 - =0.206 and KOV,HAc=0.674[Formula presented], and for the desorption pKMeCO3 - Ac- =3.71. 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.