Energy efficient and environmentally friendly pervaporation-distillation hybrid process for ternary azeotrope purification

Isopropanol and acetonitrile are important chemical raw materials that are widely used in the chemi-cal industry. However, mixtures of acetonitrile, isopropanol, and water are difficult to separate as these compounds form azeotropes. The solvents were screened based on their relative volatility and toxicity. To reduce the energy consumption, a heat pump-assisted extractive distillation process was proposed. Furthermore, the pervaporation?distillation hybrid process was studied. Life cycle assessment was used to evaluate the environmental impact of the processes. The total annual cost and energy consumption of the hybrid process were 21.11% and 45.91% lower, respectively, than those of the basic process. The val-ues of global warming potential and acid potential of the hybrid process are 810.57 and 1.45, respectively, which are the smallest among those of processes studied. It is concluded that the hybrid process can not only reduce energy consumption, but is also more environmentally friendly than the other processes. ? 2021 Elsevier Ltd. All rights reserved.

Automated summary

Isopropanol and acetonitrile are important chemical raw materials with difficulty to separate when mixed with water due to the formation of azeotropes. A heat pump-assisted extractive distillation process was proposed to reduce energy consumption, while the pervaporation-distillation hybrid process was studied to improve efficiency. Life cycle assessment showed that the hybrid process had lower cost and energy consumption, as well as smaller global warming potential and acid potential compared to other processes.