Adsorption Behavior of Halogenated Anesthetic and Water Vapor on Cr-Based MOF (MIL-101) Adsorbent. Part I. Equilibrium and Breakthrough Characterizations

A synthesized chromium-based metal organic framework (Cr-MOF) was used for the adsorption of halogenated anesthetics, i.e., sevoflurane (SF). Adsorption isotherm and breakthrough experiments involving SF (reference sorbate) and water vapor were measured at 298 K and atmospheric pressure on both Cr-MOF and a commercially used reference adsorbent. The Cr-MOF MIL-101 showed a significantly higher SF adsorption capacity and much higher selectivity relative to water vapor compared to the reference adsorbent. Binary-mixture breakthrough tests demonstrated a “roll-up effect” for SF on the reference adsorbent while no such effect was observed on MIL-101

Adsorption Behavior of Halogenated Anesthetic and Water Vapor on Cr-Based MOF (MIL-101) Adsorbent. Part II. Multiple-Cycle Breakthrough Tests

Multiple-cycle breakthrough tests of a binary gas mixture of the halogenated anesthetic sevoflurane (SF) and water vapor were performed on both the synthesized chromium-based metal organic framework (Cr-MOF) and a conventionally used reference adsorbent. At 1 vol % SF and 50 % relative humidity mixture composition, the Cr-MOF (MIL-101) showed a significantly higher SF adsorption capacity, lower water vapor adsorption capacity, and no roll-up effect compared to the reference sample. After each adsorption measurement, the saturated column was regenerated. MIL-101 showed higher stability with minor SF capacity loss after 14 cycles, while the reference sample lost about a half of the SF capacity after 17 cycles

Study of the Accessibility of Zeolite Crystals in Polyimide Matrices. A Route to Coatings Exhibiting Selective Permeation

The accessibility of void space in MFI-type zeolite crystals, isolated and embedded in a polyimide (PI) matrix, was studied using optical microscopy coupled with an iodine indicator technique (IIT). IIT was used to estimate the adhesion between the PI matrix and the zeolitic phase, the accessibility of the zeolite void space for gas molecules as well as for characterizing the spatial distribution of embedded crystals in the composite. The channel system of the zeolitic phase in as-synthesized composites with the majority of crystals covered by a layer of PI is occupied by the solvent molecules used in composite synthesis. In untreated composites, the zeolitic phase is inaccessible to iodine sorption. Colouring patterns and colouring kinetics have been used to characterize the efficiency of the treatment for removing the PI covering layer from the crystal surface. The same techniques can be applied to characterize the treatment with regard to the desorption of solvents ( N- methyl-2-pyrrolidone, N,N -dimethylformamide, n-heptane) from the silicalite-1 channel system