Environment-Oriented Assessment of Hybrid Methods for Separation of N-Propanol–Water Mixtures: Combination of Distillation and Hydrophilic Pervaporation Processes

This study presents a novel approach to the dehydration of n-propanol using three hybrid methods-D + HPV, D + HPV + D, and D + HPV + D with heat integration-each combining distillation (D) and hydrophilic pervaporation (HPV) without the use of additional solvent agents, as in the most common separation method, extractive distillation. The optimization was performed using a ChemCAD process simulator, targeting 99.9 wt% purity for n-propanol and water. This is the first research to provide a comprehensive cost estimation and carbon footprint analysis for such configurations. Results show the D + HPV + D + HI method provides the best balance of energy efficiency, environmental sustainability, and economic feasibility. It reduced heat duties by 18.5% compared to D + HPV + D, achieved similar CO₂ emissions to D + HPV with better energy efficiency, and lowered the total annual cost by 37.9% compared to D + HPV. The findings establish D + HPV + D + HI as a promising technology for sustainable and cost-effective n-propanol dehydration.