Changes in physicochemical and transport properties of a reverse osmosis membrane exposed to chloraminated seawater
Crouè, Jean-Philippe Philippe
Mariñas, Benito J.
KAUST DepartmentWater Desalination and Reuse Research Center (WDRC)
Environmental Science and Engineering Program
MetadataShow full item record
AbstractThis study contributed to improving our understanding of how disinfectants, applied to control biofouling of reverse osmosis (RO) membranes, result in membrane performance degradation. We investigated changes in physicochemical properties and permeation performance of a RO membrane with fully aromatic polyamide (PA) active layer. Membrane samples were exposed to varying concentrations of monochloramine, bromide, and iodide in both synthetic and natural seawater. Elemental analysis of the membrane active layer by Rutherford backscattering spectrometry (RBS) revealed the incorporation of bromine and iodine into the polyamide. The kinetics of polyamide bromination were first order with respect to the concentration of the secondary oxidizing agent Br2 for the conditions investigated. Halogenated membranes were characterized after treatment with a reducing agent and heavy ion probes to reveal the occurrence of irreversible ring halogenation and an increase in carboxylic groups, the latter produced as a result of amide bond cleavage. Finally, permeation experiments revealed increases in both water permeability and salt passage as a result of oxidative damage.
SponsorsRBS analyses were carried out in the Center of Microanalysis of Materials, University of Illinois at Urbana-Champaign. We acknowledge Doug Jeffers for assistance operating the RBS. This work was supported by the Water Desalination and Reuse Research Center, King Abdullah University of Science and Technology and the NSF Science and Technology Center for the Purification of Water with Systems (WaterCAMPWS) funded by NSF under agreement CTS-0120978. The opinions of this paper do not necessarily reflect those of the sponsor.
PublisherAmerican Chemical Society (ACS)