Processes and separation technologies for the production of fuel-grade bioethanol: a review

Bioethanol produced from biological resources is considered as an alternative, renewable, and sustainable energy source in the context of the circular economy. Moreover, bioethanol is a biofuel that has similar energy content to gasoline, but emits less toxic pollutants compared to fossil fuels. Yet bioethanol must be anhydrous to be mixed with regular gasoline and is then utilized as a vehicle fuel. Different techniques have been developed to obtain anhydrous ethanol. Here, we compare techniques for dehydration of bioethanol, including adsorption and distillation. We present the performance of the process, product recovery, and energy consumption of the pressure swing adsorption method, which is effective and widely used.