Influence of UV grafting conditions and gel formation on the loading and stabilization of palladium nanoparticles in photografted polyethersulfone membrane for catalytic reactions

Abstract

International audienceThis paper reports innovative coupling for the development of catalytic membrane reactors. Photografting for the modification of membrane surfaces has been extensively studied and we used the results to optimize metal nanoparticle loading. Polyethersulfone hollow fibers were modified by poly(acrylic acid) grafting and the impact of a cross-linked network and a polymer gel grafted layer on metal loading was examined. Transmission electron microscopy images showed well dispersed metal nanoparticles close to the surface. The catalytic activity of the different hollow fibers was assessed by the reduction of p-nitrophenol into p-aminophenol and a conversion yield of close to 100% was found. We demonstrated the possibility of obtaining various reactors by varying the residence time through alteration of the grafted layer

Surface photomodification of flat-sheet PES membranes with improved antifouling properties by varying UV irradiation time and additive solution pH

“…7 (b)), water permeability decreased at higher irradiation times due to the greater incorporation of hydrophilic additives onto the original PES membrane. This effect was similar to those obtained for membranes with increasing UV irradiation energy during the modification process performed by other researchers [28]. The pore size was barely affected by the UV irradiation time (see Table 3).…”

“…6. When additive was added on the surface, the water permeability decreased principally because both grafting and UV-induced modification reduced the pore size and thus water permeability decreased [28]. These results may be attributed to the higher degree of modification obtained at high additive concentrations, and also could be confirmed with the PEG rejection experiments, which calculated results are summarised in Table 3 conditions.…”

High catalytic efficiency of palladium nanoparticles immobilized in a polymer membrane containing poly(ionic liquid) in Suzuki–Miyaura cross-coupling reaction

“…Our group previously published a work on catalytic hollow fiber membranes obtained using acrylic acid as modifying agent instead of ionic liquid [33]. The PdNP mean diameter was found to be 5 72 nm in the case of poly(acrylic acid) (polyAA).…”

A novel poly(vinylidene fluoride) composite membrane for catalysis and separation

“…In order to obtain a better benefit of the nanocatalyst strategy, the porous polymeric membranes have been strongly suggested as the supports for loading noble nanocatalysts . First, polymer membranes can provide enough surfaces for the immobilization of metal NPs .…”

“…Second, the unique operating model of membranes can promote the reaction by rapidly carrying the reactants to and the products off the active surface of catalysts . In addition, the operations for use and recovery are very convenient compared with other supports . Because of the above advantages, several researchers have prepared different composite membranes with noble NPs for the catalytic applications .…”