TY - JOUR
T1 - Polyelectrolyte-based sacrificial protective layer for fouling control in RO desalination
AU - Son, Moon
AU - Yang, Wulin
AU - Bucs, Szilard
AU - Nava-Ocampo, Maria F.
AU - Vrouwenvelder, Johannes
AU - Logan, Bruce E.
PY - 2018
Y1 - 2018
N2 - Reverse osmosis (RO) membranes inevitably foul due to the accumulation of material on the membrane surface. Instead of trying to reduce membrane fouling by chemical modification of the membrane, a different approach was taken here based on adding a sacrificial coating of two polyelectrolytes onto the membrane. After membrane fouling, this coating was removed by flushing with a highly saline brine solution, and a new coating was regenerated in situ to provide a fresh protective layer (PL) on the membrane surface. The utility of this approach was demonstrated by conducting four consecutive dead-end filtration experiments using a model foulant (alginate, 200 ppm) in a synthetic brackish water (2,000 ppm NaCl). Brine removal and regeneration of the PL coating restored the water flux to an average of 97 ± 3% of its initial flux, compared to only 83 ± 3% for the pristine membrane. The average water flux for the PL coated membranes was 15.5 ± 0.6 L m-2 h-1 until the flux was decreased by 10% versus its initial flux, compared to 13.4 ± 0.5 L m-2 h-1 for the non-treated control. The use of a sacrificial PL coating could therefore provide a more sustainable approach for addressing RO membrane fouling.
AB - Reverse osmosis (RO) membranes inevitably foul due to the accumulation of material on the membrane surface. Instead of trying to reduce membrane fouling by chemical modification of the membrane, a different approach was taken here based on adding a sacrificial coating of two polyelectrolytes onto the membrane. After membrane fouling, this coating was removed by flushing with a highly saline brine solution, and a new coating was regenerated in situ to provide a fresh protective layer (PL) on the membrane surface. The utility of this approach was demonstrated by conducting four consecutive dead-end filtration experiments using a model foulant (alginate, 200 ppm) in a synthetic brackish water (2,000 ppm NaCl). Brine removal and regeneration of the PL coating restored the water flux to an average of 97 ± 3% of its initial flux, compared to only 83 ± 3% for the pristine membrane. The average water flux for the PL coated membranes was 15.5 ± 0.6 L m-2 h-1 until the flux was decreased by 10% versus its initial flux, compared to 13.4 ± 0.5 L m-2 h-1 for the non-treated control. The use of a sacrificial PL coating could therefore provide a more sustainable approach for addressing RO membrane fouling.
UR - http://www.scopus.com/inward/record.url?scp=85052289039&partnerID=8YFLogxK
U2 - 10.1021/acs.estlett.8b00400
DO - 10.1021/acs.estlett.8b00400
M3 - Article
AN - SCOPUS:85052289039
SN - 2328-8930
VL - 5
SP - 584
EP - 590
JO - Environmental Science and Technology Letters
JF - Environmental Science and Technology Letters
IS - 9
ER -