Preparation And Performance Study Of Gas Separation Membrane Based On Self-porous Polymer Hollow Nanospheres

Membrane technology stands out among various gas separation methods,because of its inherent advantages such as small footprint,modular design,simple continuous operation,low energy consumption and lower cost.The membrane with excellent permeation-separation performance were the focus of the membrane technology.The hollow nanoparticle of polymer is a novel filler of mixed matrix membrane(MMMs).There are various of advantages of polymeric hollow nanoparticle in gas separation.Firstly,because of the hollow nature of these materials,they have the advantage of“the channel without resistance”.Secondly,the hollow structure of these materials is capable of highly efficient loading and encapsulation.Thus,it can be used to prepare core-shell nanoparticles with high performance.Thirdly,the hollow structure of the nanoparticles reduced the gas adsorption and obviously eliminated solubility selectivity.Therefore,the hollow nanoparticle of polymer was used to prepare high performance gas separation membranes.(1)The polymers of intrinsic microporosity hollow nanoparticles(PIM HNPs)were prepared based on water-in-oil-in-water multiple emulsion solvent evaporation,because of the“the channel without resistance”of hollow nanoparticles.The PIM HNPs were introduced into poly ether-block-amide(Pebax),poly ethylene oxide(PEO)and poly(ethylene glycol)diacrylate(PEGDA)to prepare MMMs.And gas transport property of the PIM HNPs/polymer MMMs was investigated.The MMMs without defects were prepared for excellent compatibility between PIM HNPs and polymer matrix.Compared with the original membrane,the CO₂permeability of PIM HNPs/Pebax MMMs?PIM HNPs/PEO MMMs and PIM HNPs/PEGDA MMMs was enhanced by 2.01 times,3.83 times and 1.43 times,respectively.Meanwhile,the CO₂/N₂selectivity of MMMs was decrease slightly.(2)The amino acid ionic liquids(AAILs)were introduced into PIM HNPs to improve CO₂permeation-separation performance,because of highly efficient loading and encapsulation.A serious of MMMs,based on Pebax and AAILs@PIM(core-shell)composite nanoparticles(AAILs@PIM(core-shell)CNPs),were prepared.Gas transport property of the(AAILs@PIM(core-shell)CNPs)/Pebax MMMs was investigated.It is observed that the CO₂/N₂selectivity of AAILs@PIM(core-shell)CNPs/Pebax MMMs was increase 2.33-fold and exhibit high CO₂permeability at 65oC.(3)A series of symmetric membranes and asymmetric composite membranes were prepared by self-assemble of PIM HNPs in a proper manner,because of the low gas adsorption of PIM HNPs.The gas permeation-separation performances of the self-assembled membranes were reported.It is reported that the self-assembled composite membranes exhibited remarkable H₂permeance(up to thousands of GPU,Gas Permeation Unit,1 GPU=3.35×10^-10mol/(s m²Pa)=10^-6cm³(STP)/(cm²s cm Hg))with excellent H₂/CO₂selectivity(>10).