Polysulfone/silica nanoparticle mixed-matrix membranes for gas separation

Abstract

Mixed-matrix membranes (MMMs) are based on polymeric membranes filled with inorganic particles as a means to improve their gas separation performance. In this study, MMMs were prepared from polysulfone (PSf) containing embedded nonporous fumed silica nanoparticles and the gas permeation properties of the resulting membranes were investigated. Physical properties such as film density, thermal degradation and glass transition temperature of PSf/silica MMMs were characterized. The distribution of the silica nanoparticles in PSf was observed by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Furthermore, the interface between the polymer and silica agglomerates was studied in relation with the gas transport properties. The gas permeabilities of hydrogen, helium, oxygen, nitrogen, methane, and carbon dioxide were measured as a function of silica volume fraction and diffusion and solubility coefficients were determined by the time-lag method. The effect of silica nanoparticles in PSf membranes on gas permeability is in contrast with predictions based on the Maxwell model. The O 2 permeability is approximately four times higher and CH 4 permeability is over five times greater than in a pure PSf membrane. However, the performance comprising permeability versus selectivity of PSf/silica MMMs for O 2 /N 2 and CO 2 /CH 4 follows a similar slope to that of the trade-off upper bound with increasing silica content. Crown

Gas transport behavior of mixed-matrix membranes composed of silica nanoparticles in a polymer of intrinsic microporosity (PIM-1)

“…Because of the resulting increase in free volume, the gas permeabilities generally increase with silica content, whereas the selectivities for permanent gases, such as oxygen/nitrogen, are concurrently compromised. This phenomenon has been investigated and confirmed in our previous study [8] through the addition of silica nanoparticles in conventional lowfree-volume polysulfone. It has been observed [9,10] that the relative permeability (i.e., the ratio of permeability of silica-filled polymer to that of unfilled polymer) increased with the penetrants' molecular size, leading to a considerable decrease in the selectivity of gas pairs such as O 2 /N 2 and CO 2 /CH 4 .…”

High performance mixed matrix membranes (MMMs) composed of ZIF-94 filler and 6FDA-DAM polymer

“…Journal of Membrane Science 550 (2018) 198-207 related to (1) disruption of the chain packing of the polymer, (2) porosity introduced by MOF particles [34] and (3) increase in the polymer free volume [56][57][58]. The characterization of the MMM shows that in our case the MOF distribution is quite even throughout the membrane with good adhesion between the MOF filler and the polymer.…”

Elucidation on the Effect of Operating Temperature to the Transport Properties of Polymeric Membrane Using Molecular Simulation Tool

“…Later, the polymeric membrane chain has been folded into Amorphous Cell module adopting Construction task. The polymer chains have been embedded in the hypothetical cell under the periodic condition at initial density corresponding to 70% of the targeted experimental density (1.24 g/cm 3 ) [16]. Similarly, the COMPASS force field has been adopted to pack the polymeric chains.…”