A GAS SEPARATION ARTICLE, A METHOD FOR PRODUCING SAID GAS SEPARATION ARTICLE AND USE THEREOF

Abstract

The disclosure provides a method for producing a gas separation article, said gas separation article comprising: a gas separation membrane, optionally a support, and optionally an additional support said method comprising the steps of: a) providing a matrix comprising: a matrix material having a viscosity from 1 cP to 40000 cP, particles, said particles being free from functionalized carbon nanotubes, and optionally a solvent, b) contacting the matrix of step a) with a support comprising at least one side, said at least one side facing said matrix, thereby forming (i) a matrix side in contact with the support and (ii) a matrix side opposite the side in contact with the support, c) optionally contacting the matrix side opposite the side contacting the support with an additional support, d) subjecting said matrix being in contact with said support to one or more electric fields whereby the particles form particle groups in a plurality of substantially parallel planes, said particle groups in each of said plurality of substantially parallel planes being aligned substantially parallel with the one or more electric fields, e) fixating the matrix material so as to fixate the particle groups thereby forming a gas separation membrane, and f) optionally removing the support and/or the additional support.

The disclosure also provides a gas separation membrane obtainable by the aforementioned method as well as use thereof for separation of gases in a gas mixture.

Claims

1. A method for producing a gas separation article, said gas separation article comprising: a gas separation membrane, and a support, said method comprising the steps a) providing a matrix comprising: a matrix material having a viscosity from 1 cP to 40000 cP, particles, said particles being free from functionalized carbon nanotubes, b) contacting the matrix of step a) with a support comprising at least one side, said at least one side facing said matrix, thereby forming (i) a matrix side in contact with the support and (ii) a matrix side opposite the side in contact with the support, c) subjecting said matrix being in contact with said support to one or more electric fields whereby the particles form particle groups in a plurality of substantially parallel planes, said particle groups in each of said plurality of substantially parallel planes being aligned substantially parallel with the one or more electric fields, d) fixating the matrix material so as to fixate the particle groups thereby forming a gas separation membrane.

2. The method according to claim 1, wherein the particles are free from carbon nanotubes.

3. (canceled)

4. The method according to claim 1, wherein the particles are free from pores.

5. The method according to claim 1, wherein the particles comprise pores.

6. The method according to claim 1, wherein the particles comprise particles selected from the group consisting of graphene, graphene oxide, graphene oxide functionalized with amine group(s), metal-organic framework, zeolitic imidazolate framework, covalent organic framework clay silica organic framework and nickel oxide nanosheets.

7. (canceled)

8. (canceled)

9. The method according to claim 5, wherein the pore anisotropy is equal to or less than 100:1, said pore anisotropy being the ratio of the longest dimension to the shortest dimension of the pore.

10. The method according to claim 1, wherein the particles are electrically conductive particles.

11. The method according to claim 1, wherein the particles are electrically non-conductive particles.

12. The method according to claim 1, wherein the particles of the particle groups are aligned substantially parallel with the one or more electric fields.

13. The method according to claim 1, wherein the one or more electric fields is/are alternating electric field(s).

14. The method according to claim 1, wherein the one or more electric fields is/are substantially parallel to a plane in which the support extends.

15. The method according to claim 1, wherein the one or more electric fields is/are provided parallel to a plane in which the support extends and only to a first side of the support, said first side of the support being opposite the side of the support facing the matrix.

16. The method according to claim 1, wherein the one or more electric fields is/are provided by an interdigitated electrode.

17. The method according to claim 1, wherein the one or more electric fields is/are substantially perpendicular to a plane in which the support extends.

18. The method according to claim 1, wherein the particle groups are surrounded by the matrix material.

19. The method according to claim 1, wherein the support is porous.

20. The method according to claim 1, wherein the support is porous non-porous.

21. The method according to claim 1, wherein the gas-separation article comprises an additional support.

22. The method according to claim 1, wherein the matrix material comprises one or more of the following: monomer(s), oligomer(s), polymer(s).

23. The method according to claim 1, wherein the matrix material comprises one or more polymers selected from the group consisting of polyurethane, polyether block amide, polyimide, polydimethylsiloxane, polyethylene glycol, ethylene acrylic elastomer, perfluoropolymers, polymerized ionic liquids, polysulfone, polyimide, polyvinylamine, polyallylamine, polyethyleneimine, cyanoacrylates, rosin acrylates, ester acrylates, urethanes acrylates, silicone acrylates, amine acrylates, epoxy acrylates and polyepoxides, polyethylene, poly(tetramethylene oxide), polyethylene oxide, polyphenylene oxide, polydioxolane.

24. The method according to claim 1, wherein the support and/or the additional support comprises one or more of the following: polyethylene terephthalate (PET), polysiloxanes, polydimethylsiloxane (PMDS), poly(1-trimethylsilyl-1-propyne) (PTMSP), polyacrylonitrile (PAN), perfluoropolymers, perfluoroethers (PTFE), polyvinylidene fluoride (PVDF), polyether sulfones (PES), polysulfones (PSU), polyimides (PI), polyetherimides (PEI), polyamides, polyamideimides, polycarbonates (PC), polyesters, polyether ether ketone (PEEK), polye(ethylene oxide) (PPO), polyacrylates, polymethacrylates, cellulose acetate, polyethylene (PE), polypropylene (PP) polytetrafluoroethylene (PTFE), polymethylpentene (PMP), copolymers of one or more of the aforementioned polymers.

25. The method according to claim 1, wherein the fixating of step d) comprises solvent evaporation and/or curing.

26. The method according to claim 1, wherein the fixating of step d) comprises converting the matrix into a solid material.

27. A gas separation article obtainable by the method according to claim 1.

28. Use of a gas separation article according to claim 27 for separation of gases in a gas mixture comprising one of more of the following: oxygen and nitrogen, carbon dioxide and methane, carbon dioxide and natural gas carbon dioxide and biogas carbon dioxide and nitrogen hydrogen sulfide and methane, hydrogen sulfide and natural gas hydrogen sulfide and biogas, helium and nitrogen, hydrogen and methane, helium and methane, helium and hydrogen, hydrogen and carbon dioxide, helium and carbon dioxide, nitrogen and methane, hydrogen and nitrogen, hydrogen and carbon monoxide propene and nitrogen, ethylene and nitrogen, ethylene and argon, vapor and natural gas.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0135] FIG. 1 shows a cross section of a gas separation membrane comprising a plurality of particle groups that are parallel to a plane in which the support extends.

[0136] FIG. 2 shows a cross section of a gas separation membrane comprising a plurality of particle groups that are perpendicular to a plane in which the support extends.

[0137] FIG. 3 shows a process for producing a gas separation article comprising use of an interdigitated electrode.

[0138] FIG. 4 shows a top view microscope image of a gas separation article produced using an interdigitated electrode.

[0139] FIG. 5 shows a process for producing a gas separation article comprising use of a top electrode and a bottom electrode.

[0140] FIG. 6 shows a top view microscope image of a gas separation article produced using a top electrode and a bottom electrode.

[0141] FIG. 7 shows a gas permeation setup.

[0142] FIG. 8 shows trends in a gas permeation test.

[0143] FIG. 9 shows the CO.sub.2 permeability of film with three different concentrations of particles.

DETAILED DESCRIPTION OF EMBODIMENTS

[0144] FIG. 1 shows a cross section of a gas separation membrane comprising a plurality of particle groups that are parallel to a plane into which a support extended. Depending on the choice of the solidified viscous material and the particles of the plurality of particle groups some gases will be able to pass through the plurality of particle groups while others will not. As a result, gases in a gas mixture may pass through the gas separation membrane at different speeds resulting in separation of the gases. FIG. 1 shows an example where carbon dioxide (CO.sub.2) is able to pass through the plurality of particle groups while nitrogen (N.sub.2) and methane (CH.sub.4) can only pass though the solidified membrane material.

[0145] FIG. 2 shows a cross section of a gas separation membrane comprising a plurality of particle groups (only one particle group is shown) that are perpendicular to a plane into which a support extended. In this example, the plurality of particle groups comprise an amine functionality (NH.sub.2) that interacts reversibly with the carbon dioxide 1 (CO.sub.2) to increase the speed with which it passes through the solidified viscous material. Such an interaction is absent for the mixture 2 of nitrogen (N.sub.2) and methane (CH.sub.4) which pass through the solidified membrane material more slowly than the carbon dioxide.

[0146] FIG. 3 shows a process for producing a gas separation article comprising use of an interdigitated electrode. The interdigitated electrode is placed below the support and generates an electric field that arranges the particles into a plurality of particle groups that are parallel to the plane in which the support extends. The use of an additional support is also illustrated. The arrow shows the direction of the electric field. In FIG. 3, the numbers designate the following: 1 is matrix, 2 is support, 3 is roll, 4 is additional support, 5 is direction of the electric field, 6 is electrode, 7 is curing chamber, 8 is solidified matrix.

[0147] FIG. 4 shows a top view microscope image of a gas separation article produced using an interdigitated electrode. In this case, the particles are graphite particles and the membrane thickness is about 200 micrometers.

[0148] FIG. 5 shows a process for producing a gas separation article comprising use of a top electrode and a bottom electrode. The electrodes generate an electric field that arranges the particles into a plurality of particle groups that are perpendicular to the plane in which the support extends. The arrow shows the direction of the electric field. In FIG. 5, the numbers designate the following: 1 is matrix, 2 is support, 3 is roll, 4 is additional support, 5 is direction of the electric field, 6 is top electrode, 7 is bottom electrode, 8 is curing chamber, 9 is solidified matrix.

[0149] FIG. 6 shows a top view microscope image of a gas separation article produced using a top electrode and a bottom electrode. In this case, the particles are graphite particles.

[0150] FIG. 7 shows a gas permeation setup. V stands for valve, and PI stands for pressure indicator. The components within the dashed lines are contained within a thermostatic chamber denominated TC. The sample holder may be denominated S. The gas supply may be denominated GS. The vacuum may be denominated VAC.

[0151] FIG. 8 shows trends in a gas permeation test.

[0152] FIG. 9 shows the CO.sub.2 permeability of three different films as described in the Examples section of this document. For the film comprising in plane aligned (IPA) graphite particles three particle concentrations were tested, namely 2 vol %, 5 vol %, and 8 vol %. For the film comprising graphite particles that had not been aligned (NA) three particle concentrations were tested, namely 2 vol %, 5 vol %, and 8 vol %. For the film comprising through plane aligned (TPA) graphite particles a single concentration of graphite particles was tested, namely 2 vol %. It was observed that the film comprising through plane aligned (TPA) graphite particle groups in a concentration of 2 vol % had a higher CO.sub.2 permeability than the film comprising graphite particles that had not been aligned as well as a film comprising in plane aligned (IPA) graphite particle groups in a concentration of 2 vol %. This shows that the permeability is affected by the way the groups of particles are aligned in the matrix. In particular, this shows that through plane aligned particle groups enhance permeability such as CO.sub.2 permeability while in plane aligned particle groups slow down permeability such as CO.sub.2 permeability.

[0153] The disclosure is further illustrated by the following non-limitative Examples.

EXAMPLES

[0154] Abbreviations

[0155] AC Alternating Current

[0156] kHz kilo Hertz

[0157] kPa kilo Pascal

[0158] kV kilo Volt

[0159] rpm revolutions per minute

[0160] vol % volume

[0161] wt % weight %

[0162] Gas Permeability Vs Graphite Concentration

[0163] A viscous polymer matrix was prepared by mixing Shikoh UT6297 (i.e. urethane acrylate purchased from Nippon Gohsei and preheated to 60° C.) together with 4 wt % of Irgacure 1173 (i.e. a UV curing agent purchased from BASF) at 2000 rpm for 120 seconds in a Thinky planetary mixer. Particles were dispersed in the polymer in two steps with the same planetary mixer. The first step was mixing at 2000 rpm for 2 minutes at ambient pressure, the next step was 2000 rpm for 4 minutes at 0.2 kPa. Three different mixes of polymer matrix and graphite particles TS0141 P (Purchased from Asbury carbon) were prepared and were made into membranes separately. The graphite particles had an average diameter of 29.7 micrometer, and standard deviation 15.3 micrometer, and a d50 value with respect to volume that was 30.13. The concentration of particles was 2 vol %, 5 vol % and 8 vol % based on the total volume of the sample.

[0164] The mixtures of polymer and particles was knife coated to a film of thickness 200 pm on a PET support. An additional PET support was used on the opposite side, creating a sandwich of PET, viscous material and PET. The particles in the viscous material was then aligned either through plane (TPA) (FIG. 6), in-plane (IPA) (FIG. 7) or not at all (NA). As used herein, TPA alignment of particles intends alignment of the particle groups to be substantially perpendicular to a plane into which the support(s) extend(s). Further, IPA alignments intends alignment of the particle groups thereof to be substantially parallel to a plane into which the support(s) extend(s). The determination of whether the alignment was in plane or through plane was made by selecting the electrode setup used to do the alignment and verified by inspecting the particles' orientation using an optical microscope. The alignment was performed with an AC electric voltage of 1-250 kHz and 0.1kV-1 kV. After the particle alignment, the viscous material was fixated by curing the polymer with ultraviolet light. The two PET supports were then removed from the fixated viscous creating a free-standing film that was tested in the permeability setup described below.

[0165] Gas Permeation Tests:

[0166] Gas permeation measurements were performed using a constant volume variable pressure setup, where the permeability measurement was performed by measuring the variation of pressure in the permeate compartment. The film was initially evacuated overnight to ensure the complete removal of penetrants within the film. A vacuum test was then performed to measure the leak rate. Subsequently, the upstream side is pressurized to a certain pressure (˜2 bar) while the pressure was monitored on the downstream side. The pressure in the downstream side increased slowly in the beginning and then reaches steady state conditions (represented by a constant derivative term). When this is reached, the permeability (P.sub.i) was calculated as:

[00001]$\begin{array}{cc}{P}_i=\left(\frac{{\mathrm{dp}}_d}{\mathrm{dt}}{.Math.}_{\mathrm{test}}-\frac{{\mathrm{dp}}_d}{\mathrm{dt}}{.Math.}_{\mathrm{leak}}\right).Math.\frac{V_d}{\mathrm{RTA}}.Math.\frac{\ell }{\left(p_u-p_d\right)}\mathrm{where}\frac{{\mathrm{dp}}_d}{\mathrm{dt}}& \left(1\right)\end{array}$

is the derivative term of the variation in the downstream pressure, V.sub.d is the calibrated downstream volume, R is the gas constant, T is the operating temperature, A is the permeating area, l is the membrane thickness and p.sub.u−p.sub.d is the driving force, expressed as the difference between the upstream and downstream pressure. From the transient phase it is also possible to calculate the diffusion coefficient (D.sub.i) according to the time-lag (ϑ.sub.L) observed in the experiment, as:

[00002]$\begin{array}{cc}{D}_i=\frac{{\ell }^2}{{\vartheta }_L}& \left(2\right)\end{array}$

[0167] Finally, according to the solution diffusion mechanism, where the permeability can be calculated as product of the diffusion and the solubility coefficients, the latter can be estimated for the given experimental conditions.

[0168] Starting from the permeability, the ideal gas selectivity can also be calculated as ratio of the permeability coefficient (also called “perm-selectivity”). This parameter gives a good estimation of the separation performance of the membrane, although deviations may be found for real gaseous mixtures.

[0169] The gas tested was pure CO.sub.2, i.e. carbon dioxide.

[0170] Gas Permeation Results:

[0171] FIG. 9 shows the measured CO.sub.2 permeability for the samples described above. The gas permeability is clearly affected both by the electric field alignment of particles and the concentration of particles. Comparing the not aligned (NA) samples with the two others, shows that through plane alignment (TPA) increased the permeability, whereas in plane alignment (IPA) decreased it. This is because in the IPA-sample the electric field aligns and orients the two-dimensional graphite particles and groups thereof parallel to the plane into which the PET support(s) extended, creating a barrier for the CO.sub.2 molecules. In the TPA sample the particles and groups thereof were aligned and oriented perpendicular to the plane into which the PET supports extended, which is an orientation that blocks the gas to the lowest degree.