Investigating steam regeneration as rapid temperature swing adsorption method for biobutanol recovery using an activated carbon monolith

An activated carbon monolith was utilized for biobutanol recovery in a rapid temperature swing adsorption (RTSA) process with steam regeneration. We conducted cyclic adsorption–desorption experiments to assess the process performance under varying steam flow rates, steam durations, and flushing conditions. The results indicate that steam regeneration efficiently removes biobutanol, increasing the butanol concentration in the condensate by up to 37 wt%, which is an 18-fold increase compared to the inlet concentration. Although higher steam flow rates or longer steam durations improved butanol adsorption capacity, they led to a reduced butanol concentration in the recovered product, indicating a trade-off between capacity and product concentration. We observed that the total amount of steam used during the regeneration step is the primary factor influencing recovery and product concentration. The optional flushing step did not significantly impact cyclic performance, suggesting that it can be omitted without affecting process efficiency. These findings underscore the potential of steam regeneration on activated carbon monoliths as an effective adsorbent for biobutanol recovery, providing a promising alternative to more energy-intensive separation methods.