Study on the influence of the free volume of hybrid membrane on pervaporation performance by positron annihilation spectroscopy

Investigation on positron annihilation characteristics of CO2-exposed zeolite

“…As can be deduced from Fig. 4, the spectrum at vacuum conditions (dehydrated zeolite 4A) gave the longest lifetime, whereas that at ambient conditions (hydrated zeolite 4A), at which water molecules were sorbed in the cavities of zeolite 4A, gave the shortest lifetime [20,36]. The PAL spectrum at 5 atm CO 2 was similar to that at ambient conditions, indicating that CO 2 molecules were sorbed in the cavities of the zeolite.…”

Cation exchange hybrid membranes prepared from PVA and multisilicon copolymer for application in alkali recovery

“…The membranes need high stability and durability in alkaline solution, as well as favorable permeability and selectivity. Inorganic-organic hybrid membrane as a potential ''next generation'' membrane is proposed and has attracted much more attention recently [7][8][9][10][11] as a result of its extraordinary properties arising from the synergism between the properties of two different building blocks.…”

In situ regulation of micro-pore to design high performance polyimide membranes for pervaporation dehydration of isopropanol

“…This is attributed to the collective effects of (1) electrostatic cross-linking due to the existence of iron(III) ions, (2) decomposition of acetylacetonate as a micro-pore former, (3) decarboxylation induced cross-linking and (4) in-situ formation of iron oxide nanoparticles, as proved by XRD, PALS and vapor sorption characterizations. Table 3 shows pervaporation performance of the best membrane in this study compared with various composite membranes for IPA/water dehydration reported in literatures [34,57,[60][61][62][63][64][65]. The newly developed PI-20%-400 membrane has a molar selectivity which is comparable with those high performance membranes in literatures, while its water permeability is better than most of them.…”