Related Experiment Video
Updated: May 22, 2026

Ion-Exchange Membranes for the Fabrication of Reverse Electrodialysis Device
Published on: July 20, 2021
Pressure retarded osmosis for energy production: membrane materials and operating conditions
1Department of Construction Environment Engineering, University of Science & Technology, Daejeon, Republic of Korea.
Abstract:
Pressure retarded osmosis (PRO) is a novel membrane process to produce energy. PRO has the potential to convert the osmotic pressure difference between fresh water (i.e. river water) and seawater to electricity. Moreover, it can recover energy from highly concentrated brine in seawater desalination. Nevertheless, relatively little research has been undertaken for fundamental understanding of the PRO process. In this study, the characteristics of the PRO process were examined using a proof-of-concept device. Forward osmosis (FO), reverse osmosis (RO), and nanofiltration (NF) membranes were compared in terms of flux rate and concentration polarization ratio. The results indicated that the theoretical energy production by PRO depends on the membrane type as well as operating conditions (i.e. back pressure). The FO membrane had the highest energy efficiency while the NF membrane had the lowest efficiency. However, the energy production rate was low due to high internal concentration polarization (ICP) in the PRO membrane. This finding suggests that the control of the ICP is essential for practical application of PRO for energy production.
Related Concept Videos
Osmosis and Osmotic Pressure of Solutions
Osmosis
Water, like other substances, moves from a high concentration of free water...
Osmosis
Osmotic Pressure
ATP Driven Pumps I: An Overview
There are four main types of ATP-driven pumps - P-type, V-type, F-type, and ABC transporter. All these pumps are of varying complexities and are...
The Resting Membrane Potential

