Minimization of chemicals use during adsorptive recovery of succinic acid

In adsorptive separation processes, regeneration of the adsorbent plays an important role. Depending on the type of product the regeneration strategy might differ from one process to another. In this study, the desorption of succinic acid from a high silica ZSM-5 adsorbent is studied, using displacement by an organic solvent or CO₂, or temperature swing. According to a number of process criteria and solvent selection criteria, 2-butanone performed better than the other displacing agents studied. However, the subsequent regeneration step involved desorption of butanone, which proved to be difficult and required a temperature above the normal boiling point of water under elevated pressures. Such a temperature swing with hot water can also be applied for direct succinic acid desorption without intermediate displacement by butanone. A countercurrent continuous adsorption process was modeled to compare these options. Direct temperature swing using pressurized water at >100 °C proved to be more attractive to achieve a sustainable process.