posted on 2019-02-20, 00:00authored byLorena Paseta, Daniel Antorán, Joaquín Coronas, Carlos Téllez
Nanofiltration
can be a useful tool to remove pharmaceuticals in
water sources. The performance of the most used thin film composite
(TFC) membranes, typically with a thin polyamide (PA) layer, can be
improved using thin film nanocomposite (TFN) membranes obtained by
the introduction of a filler within the PA layer. In this work, to
control the positioning of the filler two kinds of PA/metal–organic
framework (MOF) bilayered TFC (BTFC) membranes, PA/ZIF-93 and PA/HKUST-1,
were synthesized onto polyimide supports. First, the interfacial synthesis
was used for the preparation of a MOF layer, and second, a PA layer
was synthesized by interfacial polymerization. These BTFC membranes
were applied in the nanofiltration of diclofenac and naproxen aqueous
solutions obtaining a maximum water permeance of 33.1 and 24.9 L·m–2·h–1·bar–1, respectively, with a rejection of ≥98% when HKUST-1 was
used. These permeance improvements (using diclofenac, 4.9 and 3.4
times the value of the TFC and TFN membranes, respectively) are related
to the PA layer thickness, MOF porosity, membrane hydrophilicity,
and membrane roughness.