Systematic Bench-Scale Assessment of Perchlorate (Cl04-) Rejection Mechanisms by Nanofiltration and Ultrafiltration Membranes
Y Yoon, G Amy, J Cho, J J. Pellegrino
Measurements of the rejection of Perchlorate anion (C104-) have been performed using two thin film composite (TFC) nanofiltration (NF) membranes and four ultrafiltration (UF) membranes. The latter four membranes are all from the same manufacturer and, ostensibly, from the same material family. These were chosen to systematically change the membrane's steric properties while keeping the same material chemistry, thus, the enthalpic interactions should stay constant. The Perchlorate anion (at a concentration of 100 mg/L of C104- by spiking with KC104) was presented to the membrane as a pure component, inbinary mixtures with other salts, and at varying pH and ionic strength (conductivity). Also, a natural source water was spiked with Perchlorate anion and used to dobument the effects of a complex mixture, including natural organic matter (NOM), on the observed rejection. All filtration measurements were performed at approximately the same permeate flow rate in order to minimize artifacts from mass transfer at the membrane interface. In general, the results indicate that,in a pure component system, target ions (in this case C104-) can be significantly excluded from like-charged membranes with pores large with respect to the size of the ion, but this rejection capability decreases in the presence of a sufficient amount of other ions that can screen the apparent electrostatic force field.
Separation Science and Technology
nanofiltration, perchlorate, ultrafiltration, water treatment
, Amy, G.
, Cho, J.
and Pellegrino, J.
Systematic Bench-Scale Assessment of Perchlorate (Cl0<sub>4</sub><sup>-</sup>) Rejection Mechanisms by Nanofiltration and Ultrafiltration Membranes, Separation Science and Technology
(Accessed December 6, 2023)