Water Permeability Increase in Ultrafiltration Cellulose Acetate Membrane Containing Silver Nanoparticles

Abstract

Inorganic nanoparticles incorporation in polymer membranes for filtration processes has attracted the attention of researchers in order to improve in some ways their performance. In this work, AgNPs were synthesized "in situ" in cellulose acetate (CA) membrane by chemical reduction of a silver salt. The membranes were prepared by the nonsolvent induced phase inversion method. Asymmetric membranes without (CA-M) and with adsorbed AgNPs (CA-Ag-M) were obtained. Ultrafiltration properties were confirmed for both membranes (16 nm of average pore diameter) and average crystallite size of 21 nm for the adsorbed AgNPs was computed. Contact angle measured with Milli-Q water and dry CA-Ag-M is near zero while for the CA-M is around 80°. The CA-M showed water permeability of 214 Lh^-1m^-2, while the CA-Ag-M permeability was 1651 Lh^-1m^-2.

Keywords:
silver nanoparticles; cellulose acetate membrane; permeability; ultrafiltration; contact angle