Reverse osmosis

About: Reverse osmosis is a research topic. Over the lifetime, 20780 publications have been published within this topic receiving 299185 citations. The topic is also known as: RO.

Membrane technology in renewable-energy-driven desalination

Abstract: Growing requirements of freshwater and unsustainable nature of fossil fuels are driving the interest in using renewable energy for desalination applications. Due to their less energy-intensive nature and small footprint, membrane-based desalination operations are gaining significant interest in this regard. Substantial efforts have been observed in integrating traditional renewable and relatively green sources of energy (wind, solar, geothermal, tidal and nuclear) with membrane-based desalination operations, mainly reverse osmosis (RO) and electrodialysis (ED). Due to recent developments and progresses in membrane technology, interesting membrane operations including membrane distillation (MD), pressure retarded osmosis (PRO) and reverse electrodialysis (RED) have emerged. These operations are capable of generating clean and sustainable electricity from various waste streams including brine and impaired water which otherwise are considered environmental liabilities. PRO and RED require mixing of a high salinity solution (such as seawater or brine and wastewater, respectively) with a low salinity solution to generate electricity. MD has shown the potential to generate freshwater and electricity as standalone process. Integration of MD with PRO or RED enhances the performance of these processes and provides a clean and sustainable route to produce freshwater and energy. The current study reviews the recent progresses and developments in applying renewable energy sources in membrane-based desalination with special attention on emerging membrane operations with proven capability to generate energy from wastewater streams.

Molecular Layer-by-Layer Assembled Thin-Film Composite Membranes for Water Desalination

Abstract: Molecular layer-by-layer (mLbL) assembled thin-film composite membranes fabricated by alternating deposition of reactive monomers on porous supports exhibit both improved salt rejection and enhanced water flux compared to traditional reverse osmosis membranes prepared by interfacial polymerization. Additionally, the well-controlled structures achieved by mLbL deposition further lead to improved antifouling performance.

Use of Polyelectrolyte Layer-by-Layer Assemblies as Nanofiltration and Reverse Osmosis Membranes

Abstract: Measurements of ion transport and water flux across ultrathin multilayered membranes of polyelectrolytes were carried out under nanofiltration and reverse osmosis conditions. The polyelectrolyte membranes were prepared upon alternating electrostatic layer-by-layer adsorption of polyvinylamine (PVA) and polyvinyl sulfate (PVS) on porous supports. The pressure-driven transport of aqueous electrolyte solutions containing NaCl, Na2SO4, MgCl2, and MgSO4 in 1 and 10 mM concentration was investigated. For MgCl2 and MgSO4, a complete rejection was observed independently from the concentration of the feed solution and the pressure applied. For NaCl and Na2SO4, the rejections were 84 and 96% at 5 bar, and 93.5 and 98.5% at 40 bar, respectively. The hydraulic permeability of the composite membrane was 113.7 mL/(m2 h bar). It was only little affected by the presence of salt. At low and moderate pressure the membranes are suitable for water softening applications, while at pressures of 40 bar or higher they can be use...