Butene isomers separation on titania supported MFI membranes at conditions relevant for practice

Metal organic framework based mixed matrix membranes: An increasingly important field of research with a large application potential

“…This increase in selectivity with pressure has very important consequences for applications like natural gas and biogas upgrading, where the retentate has to be kept pressurized. In addition, this behavior is opposite to the one shown by most inorganic membranes, where decrease in selectivity at elevated pressures is an intrinsic property [85][86][87][88] or due to the presence of small defects that become more important at high pressures [89,90]. We speculate that the increase of selectivity is due to the intrinsic flexibility of the MOF filler: as pressure increases, adsorption in the Table 1.…”

Adsorption and Diffusion – Basis for Molecular Understanding of Permeation through Molecular Sieve Membranes

“…As model system to demonstrate the correla- Fig. 2 at 130°C [9]. The feed pressure was increased up to 21 bar whereas the permeate pressure was constant at 1 bar [9].…”

“…2 at 130°C [9]. The feed pressure was increased up to 21 bar whereas the permeate pressure was constant at 1 bar [9]. The three data points at each Dp derive from three independent membrane preparation and permeation tests.…”

“…2. However, the practice-relevant permeation tests of an undiluted equimolar 1-butene/i-butene mixture at 130°C showed that the mixture separation factor a decreased from initially 10 to about 5 if the pressure difference Dp across the membrane increased from 1 bar to 20 bar, which is the practice-relevant operational pressure (pressure of the equimolar undiluted feed up to 21 bar, constant permeate pressure of 1 bar) [9] (see Fig. 3).…”

Deuterium/hydrogen permeation through different molecular sieve membranes: ZIF, LDH, zeolite

“…Also in a previous study we found that in the slit pores of pressed graphite the diffusivity of the mobile component H 2 is slowed down in the binary mixture with CO 2 and as a result the real mixed gas separation factor is much lower than that one predicted by the ideal selectivity SF [16]. It seems to be a common feature that at high pore filling the adsorbed components of a mixture do not behave like the single components, that is to say, the highly mobile component is slowed down by the less mobile component as observed in previous studies As a consequence, in some industrially driven R&D projectsedespite promising single gas resultsethe mixture permeation results were by the end disappointing [39,40]. We ascribe the non-separability of a D 2 /H 2 mixture on our pore membranes at 1 bar feed pressure to this equilibration effect.…”