Meso-/macro-porous microspheres confining Au nanoparticles based on PDLA/PLLA stereo-complex membrane for continuous flowing catalysis and separation

In this work, we report the continuous flowing catalysis of meso-/macro-porous microspheres confining Au nanoparticles based on Poly (L-lactic acid)/Poly (D-lactic acid) (PDLA/PLLA) stereo-complex membrane. Plentiful meso-/macro-porous microspheres (1-2 mu m diameter) were assembled inside the stereo-complex Poly (lactic acid) (PLA) membrane through the phase inversion, which were thought to play a critical role on robustly capturing and confining Au nanoparticles (30-40 nm diameter) with the loading content of 1.56 g/m(2), as demonstrated by the SEM, TEM, EDX and XPS. The Au nanoparticles-loaded stereo-complex PLA membrane exhibits an instantaneous reduction for 4-nitrophenol in a continuous flowing operation with the dynamic reactive constant 386 min(-1) under the water flux of 262.8-1440 L/m(2).h, which was similar to 2900 fold higher than the static catalytic. Moreover, the catalytic membrane keeps above 90% conversion even after 140 min continuous flowing. In addition, The Au nanoparticles-loaded stereo-complex PLA membrane demonstrated the better bovine serum albumin (BSA) antifouling and ink colloid rejection. All results verified that the stereo-complex PLA membrane provided a feasible platform for meso-/macro-porous microspheres confining Au nanoparticles as high efficient heterogeneous catalysts. The proposed strategy could be extended to other robust heterogeneous catalysts for membrane catalytic applications.