Ultrasound-based separation of ethanol-water mixtures is economically advantageous and sustainable

Ultrasonic separation of azeotropic mixtures has long been proposed as a promising separation technique, especially for ethanol-water mixtures. Since ultrasonic separation operates at ambient pressure, uses electricity as an energy source, and does not involve phase transitions, it is expected to have environmental advantages over conventional technologies. However, the economic and environmental potential of ultrasonic separation on a commercial scale remains unknown. We conduct a combined experimental and computational study leading to a data-driven techno-economic analysis and life cycle assessment of commercial-scale ultrasonic separation. We obtain experimental measurements of ethanol-water ultrasonic separation under room pressure, temperatures of 10°C to 55°C, and carrier gas flow rates of 1 to 5 L min−1 and use them to develop process simulations. Our economic and environmental evaluations show that commercial-scale ultrasonic separation can reduce total annualized cost by more than 10% and CO2-eq emissions by more than 40%, making it a potentially attractive alternative to conventional thermal separation technologies. [Display omitted] •Conventional technologies for producing anhydrous ethanol require pre-distillation•Pre-distillation utilizes steam energy, which can result in greenhouse gas emissions•Using only electrical energy, ultrasonic separation can break the azeotrope•Ultrasonic separation can reduce CO2 emissions by 40% and costs by 10% Thermal separations, which are used worldwide to separate chemicals, emit significant amounts of carbon dioxide. Here, Ha et al. investigate an alternative method for separating high-purity ethanol using ultrasonic waves, and comparative economic and environmental analyses of ultrasonic separation against conventional ethanol-water separation methods show potential advantages.