Thin-film nanocomposite (TFN) membrane containing amino-functionalized UZM-5 nanoparticles was synthesized by the interfacial polymerization on polyetherimide (PEI)/modified SiO2 asymmetric substrate tailored for organic solvent nanofiltration OSN process. m-Phenylenediamine (MPD) with trimesoyl chloride (TMC) was polymerized to prepare polyamide layer. UZM-5 nanoparticles (~73 nm) were synthesized then functionalized by aminopropylediethoxymethylsilane (APDEMS) and finally incorporated into polyamide (PA) selective layer at concentration ranging from 0 to 0.2 w/v %. The as-prepared TFN membranes were characterized by scanning electron microscopy (SEM), field emission scanning electron microscopy (FESEM), atomic force microscopy (AFM), attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy and contact angle measurements. The performances of membranes were also evaluated through dewaxing solvents (MEK and toluene) recovery from lube oil. FESEM and SEM images obviously confirmed that polyamide/UZM-5 nanocomposite top layer was formed on the support surface and its morphology was highly affected by UZM-5 loading. Interaction between functional groups of modified UZM-5 nanoparticles and polyamide matrix was established by ATR-FTIR. AFM results revealed that in the range of 0–0.1 w/v% zeolite loading, the surface roughness of TFN membranes decreased due to the change of polyamide structure while at 0.2 w/v % of zeolite loading, an increase in surface roughness was observed. It is also resulted in enhanced hydrophilicity of TFN membranes in the range of 0–0.1 w/v% UZM-5 loading, proved by decreased water contact angle. The permeation test results indicated that the existence of UZM-5 in polyamide selective layer improved both oil rejection and permeate flux under optimal concentration (0.02 % w/v of UZM-5).

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