New Polyamide Interfacial Composite Membrane for Reverse Osmosis

The proposed program targets the development of a new polyamide interfacial composite membrane for reverse osmosis applications, specifically in the Army's reverse osmosis water purification units. The membranes are to be improved in their resistance tobiofouling, chlorine degradation, and delamination as well as increasing water flux. These issues will be addressed by incorporating unique polymer crosslinking agents, additives, and adsorption enhancers during the interfacial polymerization process usedto make the membranes. Microporous polysulfone is a standard composite membrane substrate/support in commercial use and will be incorporated as the support layer onto which the polyamide films are deposited. Fabricated model membranes (swatches) will beevaluated according to polymer composition and processing conditions. A planar membrane module will be used to evaluate swatches for their reverse osmosis performance. Membrane selectivity and flux is evaluated by comparing permeate flow and saltconcentrations using a standardized feed stream at a fixed hydrostatic pressure. The mechanical integrity is evaluated by the rate of film delamination and failure under reverse-flow pressurization. Resistance to chlorine degradation will be evaluated onpreferred membranes exhibiting the best selectivity, flux, and mechanical integrity. Superior membrane candidates will be evaluated for competitiveness compared to existing commercial membranes. Water purification, desalination, nanofiltration, ultra purewater treatment.