Desalination of sea and geothermal water on commercial membranes using pervaporation

Freshwater scarcity is currently one of the most pressing global issues. Desalination processes offer a solution to address this challenge. In this work, pervaporation (PV) is proposed as a membrane technique with the potential to contribute to water desalination and complementing reverse osmosis in the future. Three commercial PV membranes were tested for desalination using the PV method. Four different types of water systems were used: model and real systems with salinity from the Baltic and Adriatic Seas and geothermal water from Central Poland. The efficiency and selectivity of the PV process were examined. The PERVAP 4510 membrane showed the best results, with a retention factor of >99% for two applications in model and real systems. In addition, the scaling phenomenon during the PV process was studied. Scanning electron microscopy images were used to visualize the membrane before and after 200 h of operation. The aging process of PERVAP membranes was demonstrated using the example of 2210, which showed a significant decrease in permeate production.