Water Filtration Membranes with Built-in Continuous De-Fouling

This proposal is in response to the DOE topic 12a on membrane technology, which represents an important method in water purification and recovery for industrial and environmental applications. Energy-related cost and water waste are significant issues with reverse osmosis (RO) membrane commonly used today and increased attention is being given to Nano-filtration (NF) technology. NF covers treatments of water with low salt concentration (of which there are many) and at the same time it offers benefits of complete organic molecule and particulate removal. NF offers a lower cost alternative to RO in terms of unit price and operating costs. Consequently NF is poised for rapid growth in the market. Inorganic NF membranes offer higher performance and are more durable than polymer NF membranes. Fouling, i.e. gradual performance degradation, is a recurring issue with all water membranes, and methods to either prevent or mitigate it are vigorously sought for by the research community. The overall goal of the SBIR program is to develop and commercialize a cost effective thin supported meso-porous cerium oxide (CeO2) membrane on a porous ceramic support, which includes a piezoelectric layer for continuous de-fouling. If successful the membrane is expected to solve some of the key challenges encountered in the existing membranes. With the successful completion of the program, it is expected that a cost-effective fabrication protocol becomes available for viable ceramic membranes with high selectivity and permeance that remain in operation without any fouling. In Phase I, multi-layer membrane structures will be developed, consisting of a <500 nm thin layer of meso-porous cerium oxide on macro-porous ceramic supports. At least one of the supportive layers will be made of piezoelectric material, which will generate internal ultrasound for defouling. The cerium oxide membranes will have a pore size 2-3 nm, that can be used for removal of salt and small organic molecules from dilute solutions such as hard water, and water contaminated with drugs and pesticides. Performance and stability measurements will be performed, and the de-fouling capability will be demonstrated, using a new cross-flow cell design, on synthetic water compositions, including standardized salt concentrations and inorganic or organic foulant particles. We are developing low cost ceramic membranes for purifying water from various contaminated water streams for a variety of medical, environmental and industrial applications. Commercial Applications and Other Benefits: Ceramic membranes can be applied to all areas of industries such as water treatment, chemical, medical pharmaceutical, food and beverage, milk and dairy, textiles and paper industries and where fluid remediation such as brackish and contaminated water found in the oil and gas industry, such as “fracking” fluids can be purified.