Integrated process for production of surfactin: Part 2. Equilibrium and kinetic study of surfactin adsorption onto activated carbon

Previous work has presented kinetics of pure surfactin adsorption onto activated carbon. Being an efficient biosurfactant, the lipopeptide surfactin has been produced in a bioprocess supported by the strain Bacillus subtilis ATCC 21332. This work is aimed at studying surfactin recovery directly from the culture medium. A thermodynamic study is carried out. Referring to adsorption capacity, the thermodynamic study confirmed that the adsorption of pure surfactin is an exothermic process. The capacity of surfactin adsorption from culture media shows that the activated carbon could be used as efficient adsorbent for surfactin recovery in an integrated process. The study shows the importance of the temperature for process control. Aimed at fixed bed column design, surfactin adsorption modelling on a single microporous pellet is demonstrated.