AWWA ACE62999

This slide presentation outlines a study on micropollutant rejection by high pressure reverse osmosis (RO) and nanofiltration (NF) membranes. Part 1 presents the rejection of anionic inorganic micropollutants by negatively charged membranes including chromate, perchlorate, and arsenate. Part 1 Hypotheses involves membrane properties enhancing rejection include lower MWCO and greater (negative) surface charge. Part 2 presents rejection of trace organic micropollutants by NF and RO: compound versus membrane properties. Part 2 Hypotheses - Most Past Studies Have Often Overestimated Rejections due to Short Time Frame of Tests, not Allowing for Pre-Saturation of Membrane; Compound Transport through Membrane Is Dictated by Solute-Membrane Interactions (Steric, Electrostatic, and Partitioning); and, Partitioning (either Hindered or Facilitated) Embodies Solute-Membrane Affinity, Solute Diffusion through, and Solubility in, the Membrane. Includes tables, figures.