Optimal design and experimental validation of a three-zone simulated moving bed process based on the Amberchrom-CG161C adsorbent for continuous removal of acetic acid from biomass hydrolyzate

In the production process of bio-ethanol from biomass, acetic acid is recognized as the key impurity to be removed from the sugar components that are generated by hydrolyzing biomass. In regard to this issue, it has recently been confirmed that the Amberchrom-CG161C resin was highly qualified as the adsorbent of a simulated moving bed (SMB) process for continuous separation of acetic acid from the biomass hydrolyzate, i.e., sugars. However, the previous study on the Amberchrom-CG161C SMB with the aforementioned separation goal has been limited to only a theoretical work, including some batch-chromatography tests. The experimental validation of such an Amberchrom-CG161C SMB process, including its optimal design, was attempted in this article. This task began by assembling the experimental unit of the SMB process with three zones. Its operating conditions were then optimized by using genetic algorithm. Under the optimized operating conditions, the relevant three-zone SMB experiment was conducted. The assay of all the resultant product samples verified that the SMB separation of interest was performed successfully as designed. The experimental data were also found to agree closely with the model predictions. Finally, a partial-discard strategy was applied to maintain the sugar product concentration as high as possible.

► The three-zone SMB for removal of acetic acid from sugars was optimally designed. ► The performance of the optimized three-zone SMB process was validated experimentally. ► The use of partial-discard strategy was effective in increasing sugar concentration. ► The optimal raffinate-discard length for both sugar concentration and yield was determined.