Sorption effects of co-solvents and dissolved organic compounds on supercritical CO2 permeation through a micro-porous TiO2-membrane

Effect of dense CO2 on polymeric reverse osmosis and nanofiltration membranes and permeation of mixtures of macauba oil (Acrocomia aculeata) and CO2

“…Wall and Braun[35] also observed this behaviour in organic compounds in supercritical CO 2 permeation through a hydrophilic micro-porous TiO 2 -membrane. In the same way, Moura et al[36] have found permeate fluxes for modified triacylglycerols nearly null for the BW30 membrane.…”

Nano-Filtration and Ultra-Filtration Ceramic Membranes for Food Processing: A Mini Review

“…In one experiment, a trimyristin oil, with a molecular weight (MW) of 723 Da, was nanofiltrated in the presence of hexane as a co-solvent at a pressure of 150 Bar and a temperature of 333 K achieving a rejection of 98%. The permeate flux decreased only of about 20% and recovered nearly completely within a few minutes after the injection of the substrate was stopped [70]. In another interesting test, oil was nanofiltrated.…”

“…It appears that several research groups have recently started to test the feasibility of this technique. A paper published some preliminary results produced with a supercritical fluid extraction set up where the liquid CO 2 was combined with different components typically present in these type of applications, including oils composed by triglycerides [70]. The ceramic NF membrane consisted of a layer of TiO 2 deposited on a ceramic support.…”

Preparation of Supported Ionic Liquid Membranes Using a Supercritical Fluid Deposition Method and Study of the Capillary Phase Transition of Ionic Liquids in Supercritical CO2

“…As discussed in the introduction, when a mixture of IL−scCO 2 diffuses into the nanopores, the dissolved IL in the scCO 2 may transition to the liquid phase via capillary phase transition and completely fill the pores, similar to the permeation process of the mixture of scCO 2 and PEG. 18 According to the Kelvin equation, 19 the radius of the pores in which capillary condensation occurred (Kelvin radius) increased as the relative concentration C/C st increased. C/C st refers to the ratio of the concentration of the condensed substance to the saturated concentration of that condensed substance.…”

“…The influences of the ethanol content, IL content, and preparation time on the SILM performance were studied to optimize the operating parameters, as well as to make the preparation of SILMs controllable. Wall et al 18 used a mixture of scCO 2 and polyethylene glycol (PEG, 0.018 wt %) to permeate through a TiO 2 membrane (pore size = 0.9 nm) at 50 °C and 18 MPa. The CO 2 permeance of the TiO 2 membrane decreased to 0 GPU (a gas permeance unit, ×10 −6 cm 3 (STP)•cm −2 •s −1 •cmHg −1 ) after 30 min of permeation.…”