Mass-Transfer Coefficient as an Indicator of Resin Performance: Impacts of Film-Forming Amines and Storage Time on Condensate Polishing Ion-Exchange Resins

Abstract

Ion-exchange resins used in ultrapure water

processing are known to lose effectiveness with fouling. Mass- transfer coefficient (MTC) is one property that defines

acceptable resin performance. MTC is measured by a simple column test with known feed concentration of ions at sufficient flow to achieve kinetic leakage out of bed. MTC deviation due to exposure to film-forming amines (FFAs), as well as impacts of resin storage time, are investigated. A filming amine (FA), octadecylamine (ODA), was evaluated experimentally for potential impacts on condensate polisher ion-exchange bead resins (Dowex MS 650C (H) and Dowex MS 550A (OH)). Results indicate significant reductions in MTC on both cationic and anionic resin. In addition, unused resin stored for excessive times, up to 16 years, showed MTC reduction.