Preparation and characterization of PAA/PVDF membrane-immobilized Pd/Fe nanoparticles for dechlorination of trichloroacetic acid.

Poly(vinylidene fluoride) (PVDF) microfiltration (MF) membrane was successfully hydrophilized by coating with a novel hydrophilic layer, which was mainly composed of polyvinyl alcohol (PVA), glutaraldehyde, and polyethylene glycol (PEG). Pd/Fe nanoparticles (NPs) were prepared and immobilized in hydrophilized polyacrylic acid (PAA)/PVDF MF membrane. The unmodified and modified PVDF MF membranes were characterized by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR). The membrane-supported Pd/Fe NPs exhibited high reactivity in the dechlorination of trichloroacetic acid (TCAA). The effects of several important parameters, including Pd content, Pd/Fe NP loading, the preservation time of Pd/Fe NP membrane system on the dechlorination of TCAA were investigated. The stability of Pd/Fe NP membrane system was tested, and the kinetics and product distribution of dechlorination of TCAA by Pd/Fe NP membrane system were discussed.