A comparative study of separation processes for bioethanol production

Abstract

The sustainable development of biorefineries, which use a variety of separation processes to produce bioethanol from various feedstocks is a very interesting topic today. The separation processes used by industries are considered as the most energy consuming steps for bioethanol production. Therefore, a critical review is presented of separation methods such as azotropic distillation, vacuum distillation, extractive distillation, molecular sieve adsorption, pervaporation and hybrid process. By focusing on energy consumption, the results have shown that the hybrid pervaporation-distillation process seems most appropriate. It allows a significant saving in operating costs, which equals between 30 and 40% compared to the conventional methods with easy maintenance. In addition, this process makes possible the difficult separations by improving the degree of separation to obtain high purity of bioethanol, while respecting the environment.