METHOD FOR PRODUCING AN ADSORBENT FROM ORGANOMETALLIC FRAMEWORK STRUCTURES (MOF)

Abstract

The present invention relates to a method for the production of an absorbent made of metal-organic framework structures (MOF), in the case of which at least one metal salt is converted with at least one organic ligand. The conversion is effected at a temperature greater than 100° C. in a solvent mixture which comprises DMSO and water. The invention relates in addition to an adsorbent produced with the method according to the invention or to a substrate coated with such an adsorbent and also to possibilities of use of such an adsorbent or substrate.

Claims

1-15. (canceled)

16. A method for the production of an absorbent made of metal-organic framework structures (MOF), in the case of which at least one metal salt is converted with at least one organic ligand, wherein the conversion is effected at a temperature greater than 100° C. in a solvent mixture which comprises DMSO and water.

17. The method according to claim 16, wherein the metal salt comprises at least one chemically reducible anion selected from the group consisting of nitrate, chlorite, chlorate, perchlorate, bromite, bromate, perbromate, iodite, iodate, periodate, sulphate, hydrogen sulphate, and mixtures thereof.

18. The method according to claim 16, wherein the metal is selected from the group consisting of Mg, Ca, Sr, Ba, Sc, Y, Ti, Zr, Hf, V, Nb, Cr, Mo, W, Mn, Re, Ru, Os, Fe, Co, Rh, Ir, Ni, Pd, Pt, Cu, Ag, Au, Zn, Cd, Al, Ga, In, Si, Sn, Pb, As, Sb, and Bi.

19. The method according to claim 16, wherein the at least one organic ligand has bridging oxygen-, nitrogen or sulphur atoms or the at least one organic ligand is selected from the group consisting of bidentate ligands, polydentate ligands, and mixtures thereof.

20. The method according to claim 16, wherein the at least one organic ligand is selected from the group consisting of dicarboxylic acids, tricarboxylic acids, imidazoles, triazoles and mixtures thereof, or the at least one organic ligand is selected from the group consisting of trimesic acid, terephthalic acid, 4,4′-bipyridine, biphenylbisulphonic acid, 2,6-naphthalenedicarboxylic acid, fumaric acid, isophthalic acid, phthalic acid, oxalic acid, and mixtures thereof.

21. The method according to claim 16, wherein the solvent mixture comprises between 1 and 50% by weight of water and between 50 and 99% by weight of DMSO.

22. The method according to claim 16, wherein the conversion is effected with reflux or at a temperature of 110 to 180° C.

23. The method according to claim 16, wherein the conversion is implemented at a pressure of 1 to 5 bar.

24. The method according to claim 16, wherein the reaction mixture comprises at least one supplement, which is selected from the group consisting of nitric acid, hydrofluoric acid, hydrochloric acid, hydrobromic acid, methane sulphonic acid, toluene sulphonic acid, sulphamic acid, sulphuric acid and mixtures hereof.

25. The method according to claim 16, wherein after conversion, the reaction mixture is reprocessed, the solid produced during the conversion of the reaction mixture being separated from the supernatant solution.

26. The method according to claim 16, wherein at least one substrate which is to be coated with the adsorbent is immersed in the reaction mixture as cathode together with a counter-anode and subsequently the conversion is implemented, the adsorbent being deposited on the substrate in the form of a layer, and, during conversion, a voltage being applied between the electrodes which effects a current density of 200-1,000 mA/dm.sup.2 at the beginning of the conversion.

27. The method according to claim 16, wherein the substrate is a substrate made of electrically conductive ceramic, electrically conductive plastic material, copper, aluminium and/or steel.

28. The method according to claim 26, wherein the layer has a layer thickness of 120 to 180 μm.

29. An adsorbent or substrate coated with an adsorbent, produced by the method according to claim 16.

30. A method of separating a desired gas from a mixture of gases, a method of storing a gas, or catalyzing a reaction comprising contacting the adsorbent or a substrate coated with the adsorbent according to claim 29 and carrying out the separation, storage, or catalysis.

Description

EMBODIMENT 1

[0045] A solution of 21.25 mmol (4.48 g) of trimesic acid in 160 ml of dimethylsulphoxide was heated to 90° C. in a 250 ml three-neck flask, then a room-temperature solution of 32 mmol (12.96 g) of Fe(NO.sub.3).sub.3.9H.sub.2O in 32 ml of H.sub.2O was added all at once with agitation. The yellow-green solution was refluxed with agitation for a duration of 24 h (internal temperature: 131° C.).

[0046] The resulting solid was centrifuged off and the supernatant solution, still hot, was tipped into 1 l of water, in order to avoid precipitation of potentially explosive Fe(NO.sub.3).sub.3.6Me.sub.2SO as by-product. After cleaning (washing with DMF [90° C., 5 h], ethanol [60° C., overnight] and water [90° C., 5 h]), 4.49 g of a brown-red solid was obtained. The single crystalline phase was determined by means of X-ray powder diffractometry as MIL-100.

EMBODIMENT 2

[0047] The process took place as in embodiment 1, however with reflux only for a duration of 45 min. The thus obtained, brown and slightly cloudy liquid was placed in a double-wall vessel. The outer wall was thermostatically controlled at a temperature of 45° C.

[0048] Then two sheets of 1.4301 stainless steel (1.4016 or aluminium can also be used) of the dimensions 50×50×1.5 mm were rubbed down, degreased with acetone and mounted on a specially prepared heating element, which was provided with counter-electrodes respectively at a 10 mm spacing. The blank surface of the sheets was 15 cm.sup.2 per side. The test structure was immersed in the cooled original solution and the heating power was controlled (typically 210 W) such that the temperature just below the surface of the sheets to be coated was 135° C. (determined by a thermoelement inserted in a boring). Then a voltage was set, which at the start of the test effected a current intensity of 100 mA (current density: 10 A/dm.sup.2). After 25 minutes, the current intensity had fallen to 50 mA, the test was ended, the introduced sheets were disassembled and placed in DMF and ethanol for respectively 24 h. The formed red-brown layer was determined by powder diffractometry as MIL-100.

[0049] The thus produced sheet is approx. 150 μm thick, stable per se, but only loosely joined to the substrate. A firmly adhering layer can be produced if for example 1.4568 stainless steel (trade name 17-7 PH®) is used as substrate.