Metal Organic Framework based Reverse Osmosis Membrane

Energy is the largest single expense for desalination plants, accounting for as much as half of the costs to make drinking water from the ocean. Water desalination using nanotechnology-derived reverse osmosis (RO) holds promise for providing energy efficient clean water. Physical Sciences, Inc. proposes to demonstrate high performance metal organic framework (MOF) based desalination membranes that offer the potential to provide at least a 50% reduction in energy use compared to current RO membranes for a system with not only controlled pore size but also engineered pore chemistry. The overall objective of the Phase I program is to demonstrate a MOF based desalination membrane that produces drinking water from seawater at 3.8 Wh/gallon (1 kWh/m3) or less. This increased energy efficiency will be achieved through the production of a MOF membrane with a high population of molecular pores that provide selective, high flux pure water transmission. The MOF nanopores will be fabricated within the traditional ultrafiltration (UF) polymer membrane pore structure through interfacial growth methods. These growth methods are similar to those used to produce traditional polyamide RO membranes onto UF substrates. PSI will demonstrate the fabrication of a 2 dimensional MOF nanoporous film onto a polymeric UF membrane that will provide at least an order of magnitude increase in water flux compared to a conventional Dow Filmtec SW30 polyamide RO membrane. Physical Sciences will tune the MOF based film chemistry and architecture to provide high flux, while retaining >95% salt rejection. We will confirm these projections with small scale, continuous sea water desalination using a MOF based spiral wound RO membrane. We will work with our commercialization partner, Applied Membranes, Inc., to ensure transition to pilot production during Phase II. Fresh water makes up about 2.5 percent of all the water on earth. Half of the world's population will be dealing with “water stress” conditions - defined as when the available amount of water is exceeded by demand - by 2030. Water shortages and scarcity are already a major issue in the U.S. The typical operating costs of a modern desalination plant include 69% for energy. Improvements proposed by the PI will yield a significant reduction in the power requirements of a typical desalination plant. Power reduction estimates indicate 35% reduction in the cost to produce potable water from seawater. Commercial Applications and Other Benefits: The global demand for fresh water is rising by 650 million m3 a year as energy costs are increasing as well. An improved water purification membrane will have a significant impact on world water use and cost. PSI will work with a leading manufacturer of desalination systems, Applied Membranes, Inc., during the Phase I, II and Phase III programs to successfully transition the proposed technology.