Synthesis of nanomaterial-incorporated pressure retarded osmosis membrane for energy generation

Abstract Pressure retarded osmosis (PRO) is a process that can effectively convert the osmotic pressure of a saline solution to hydraulic pressure by utilizing the Gibbs’ free energy of mixing. Even though the thermodynamic fundamentals of the PRO process are quite established, there are still certain parameters to be optimized for an economically feasible implementation of the process. Membrane performance is one of the most important parameters of the PRO processes, and almost always is the deciding factor for scale-up implementations and applications. The performance of a PRO membrane is generally measured by the power density of that membrane under certain flux and applied pressure conditions. The peak performance of a PRO membrane is usually the “go, no-go point” for the economical evaluation process. The majority of past and current research on PRO processes is focused on membrane development and concentrates on the thin film composite (TFC) membrane structure. Integration and development of nanomaterials further push the PRO membrane research toward research on high-efficiency thin film nanocomposite (TFN) membranes. In this chapter, the current developments in PRO membrane research have been summarized and a special focus has been given to the nanocomposite membrane.