WO1996004989A1 - Procede de preparation d'un catalyseur a base d'argent - Google Patents
Procede de preparation d'un catalyseur a base d'argent Download PDFInfo
- Publication number
- WO1996004989A1 WO1996004989A1 PCT/US1994/008950 US9408950W WO9604989A1 WO 1996004989 A1 WO1996004989 A1 WO 1996004989A1 US 9408950 W US9408950 W US 9408950W WO 9604989 A1 WO9604989 A1 WO 9604989A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- process according
- silver
- catalyst
- support
- cesium
- Prior art date
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- 239000003054 catalyst Substances 0.000 title claims abstract description 90
- 229910052709 silver Inorganic materials 0.000 title claims abstract description 67
- 239000004332 silver Substances 0.000 title claims abstract description 67
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 title claims abstract description 66
- 238000004519 manufacturing process Methods 0.000 title claims description 6
- 229910052783 alkali metal Inorganic materials 0.000 claims abstract description 36
- 150000001340 alkali metals Chemical class 0.000 claims abstract description 34
- TVFDJXOCXUVLDH-UHFFFAOYSA-N caesium atom Chemical compound [Cs] TVFDJXOCXUVLDH-UHFFFAOYSA-N 0.000 claims abstract description 25
- 229910052792 caesium Inorganic materials 0.000 claims abstract description 23
- 239000012298 atmosphere Substances 0.000 claims abstract description 20
- 238000010438 heat treatment Methods 0.000 claims abstract description 16
- 230000004913 activation Effects 0.000 claims abstract description 14
- VGGSQFUCUMXWEO-UHFFFAOYSA-N Ethene Chemical compound C=C VGGSQFUCUMXWEO-UHFFFAOYSA-N 0.000 claims abstract description 12
- 239000005977 Ethylene Substances 0.000 claims abstract description 12
- GGCZERPQGJTIQP-UHFFFAOYSA-N sodium;9,10-dioxoanthracene-2-sulfonic acid Chemical compound [Na+].C1=CC=C2C(=O)C3=CC(S(=O)(=O)O)=CC=C3C(=O)C2=C1 GGCZERPQGJTIQP-UHFFFAOYSA-N 0.000 claims abstract description 12
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims abstract description 11
- 239000001301 oxygen Substances 0.000 claims abstract description 11
- 229910052760 oxygen Inorganic materials 0.000 claims abstract description 11
- 239000002253 acid Substances 0.000 claims abstract description 10
- 230000003647 oxidation Effects 0.000 claims abstract description 7
- 238000007254 oxidation reaction Methods 0.000 claims abstract description 7
- MYMOFIZGZYHOMD-UHFFFAOYSA-N Dioxygen Chemical compound O=O MYMOFIZGZYHOMD-UHFFFAOYSA-N 0.000 claims abstract description 3
- 229910001882 dioxygen Inorganic materials 0.000 claims abstract description 3
- 238000000034 method Methods 0.000 claims description 36
- 230000008569 process Effects 0.000 claims description 27
- IAYPIBMASNFSPL-UHFFFAOYSA-N Ethylene oxide Chemical compound C1CO1 IAYPIBMASNFSPL-UHFFFAOYSA-N 0.000 claims description 19
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 17
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 claims description 14
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 14
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 12
- 239000011148 porous material Substances 0.000 claims description 11
- 229910002092 carbon dioxide Inorganic materials 0.000 claims description 8
- 229910052757 nitrogen Inorganic materials 0.000 claims description 8
- 150000003378 silver Chemical class 0.000 claims description 8
- 239000001569 carbon dioxide Substances 0.000 claims description 7
- 239000004215 Carbon black (E152) Substances 0.000 claims description 6
- 229930195733 hydrocarbon Natural products 0.000 claims description 6
- 150000002430 hydrocarbons Chemical class 0.000 claims description 6
- 150000007524 organic acids Chemical class 0.000 claims description 5
- 239000001307 helium Substances 0.000 claims description 4
- 229910052734 helium Inorganic materials 0.000 claims description 4
- SWQJXJOGLNCZEY-UHFFFAOYSA-N helium atom Chemical compound [He] SWQJXJOGLNCZEY-UHFFFAOYSA-N 0.000 claims description 4
- 239000012808 vapor phase Substances 0.000 claims description 4
- 230000014759 maintenance of location Effects 0.000 claims 1
- 239000000243 solution Substances 0.000 description 25
- 239000002245 particle Substances 0.000 description 11
- 238000001878 scanning electron micrograph Methods 0.000 description 10
- 239000006185 dispersion Substances 0.000 description 9
- 230000008021 deposition Effects 0.000 description 8
- 239000000463 material Substances 0.000 description 7
- RWGFKTVRMDUZSP-UHFFFAOYSA-N cumene Chemical compound CC(C)C1=CC=CC=C1 RWGFKTVRMDUZSP-UHFFFAOYSA-N 0.000 description 6
- 238000002360 preparation method Methods 0.000 description 6
- 239000002904 solvent Substances 0.000 description 6
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 5
- 238000006243 chemical reaction Methods 0.000 description 5
- 230000000694 effects Effects 0.000 description 5
- 239000000203 mixture Substances 0.000 description 5
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 4
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 4
- ZLMJMSJWJFRBEC-UHFFFAOYSA-N Potassium Chemical compound [K] ZLMJMSJWJFRBEC-UHFFFAOYSA-N 0.000 description 4
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 4
- 239000007789 gas Substances 0.000 description 4
- 229910052751 metal Inorganic materials 0.000 description 4
- 239000002184 metal Substances 0.000 description 4
- 229910052700 potassium Inorganic materials 0.000 description 4
- 239000011591 potassium Substances 0.000 description 4
- 229910052701 rubidium Inorganic materials 0.000 description 4
- IGLNJRXAVVLDKE-UHFFFAOYSA-N rubidium atom Chemical compound [Rb] IGLNJRXAVVLDKE-UHFFFAOYSA-N 0.000 description 4
- -1 silver carboxylate Chemical class 0.000 description 4
- 229910052708 sodium Inorganic materials 0.000 description 4
- 239000011734 sodium Substances 0.000 description 4
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 description 3
- 238000001035 drying Methods 0.000 description 3
- 238000007654 immersion Methods 0.000 description 3
- 150000003839 salts Chemical class 0.000 description 3
- JRZJOMJEPLMPRA-UHFFFAOYSA-N 1-nonene Chemical compound CCCCCCCC=C JRZJOMJEPLMPRA-UHFFFAOYSA-N 0.000 description 2
- MFGOFGRYDNHJTA-UHFFFAOYSA-N 2-amino-1-(2-fluorophenyl)ethanol Chemical compound NCC(O)C1=CC=CC=C1F MFGOFGRYDNHJTA-UHFFFAOYSA-N 0.000 description 2
- BVKZGUZCCUSVTD-UHFFFAOYSA-L Carbonate Chemical compound [O-]C([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-L 0.000 description 2
- YNQLUTRBYVCPMQ-UHFFFAOYSA-N Ethylbenzene Chemical compound CCC1=CC=CC=C1 YNQLUTRBYVCPMQ-UHFFFAOYSA-N 0.000 description 2
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical compound OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 description 2
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 description 2
- 150000007513 acids Chemical class 0.000 description 2
- 150000001450 anions Chemical group 0.000 description 2
- 239000007864 aqueous solution Substances 0.000 description 2
- 229910052786 argon Inorganic materials 0.000 description 2
- ZMCUDHNSHCRDBT-UHFFFAOYSA-M caesium bicarbonate Chemical compound [Cs+].OC([O-])=O ZMCUDHNSHCRDBT-UHFFFAOYSA-M 0.000 description 2
- HUCVOHYBFXVBRW-UHFFFAOYSA-M caesium hydroxide Inorganic materials [OH-].[Cs+] HUCVOHYBFXVBRW-UHFFFAOYSA-M 0.000 description 2
- NLSCHDZTHVNDCP-UHFFFAOYSA-N caesium nitrate Chemical compound [Cs+].[O-][N+]([O-])=O NLSCHDZTHVNDCP-UHFFFAOYSA-N 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 2
- 230000001627 detrimental effect Effects 0.000 description 2
- 238000005470 impregnation Methods 0.000 description 2
- JVTAAEKCZFNVCJ-UHFFFAOYSA-N lactic acid Chemical compound CC(O)C(O)=O JVTAAEKCZFNVCJ-UHFFFAOYSA-N 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 229910052744 lithium Inorganic materials 0.000 description 2
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 2
- 230000001737 promoting effect Effects 0.000 description 2
- 230000035484 reaction time Effects 0.000 description 2
- 239000012266 salt solution Substances 0.000 description 2
- 239000000377 silicon dioxide Substances 0.000 description 2
- RQZVTOHLJOBKCW-UHFFFAOYSA-M silver;7,7-dimethyloctanoate Chemical compound [Ag+].CC(C)(C)CCCCCC([O-])=O RQZVTOHLJOBKCW-UHFFFAOYSA-M 0.000 description 2
- 238000004438 BET method Methods 0.000 description 1
- XDTMQSROBMDMFD-UHFFFAOYSA-N Cyclohexane Chemical compound C1CCCCC1 XDTMQSROBMDMFD-UHFFFAOYSA-N 0.000 description 1
- 241001379910 Ephemera danica Species 0.000 description 1
- OTMSDBZUPAUEDD-UHFFFAOYSA-N Ethane Chemical compound CC OTMSDBZUPAUEDD-UHFFFAOYSA-N 0.000 description 1
- JVTAAEKCZFNVCJ-UHFFFAOYSA-M Lactate Chemical compound CC(O)C([O-])=O JVTAAEKCZFNVCJ-UHFFFAOYSA-M 0.000 description 1
- WMFOQBRAJBCJND-UHFFFAOYSA-M Lithium hydroxide Chemical class [Li+].[OH-] WMFOQBRAJBCJND-UHFFFAOYSA-M 0.000 description 1
- CTQNGGLPUBDAKN-UHFFFAOYSA-N O-Xylene Chemical compound CC1=CC=CC=C1C CTQNGGLPUBDAKN-UHFFFAOYSA-N 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 150000001242 acetic acid derivatives Chemical class 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- ITHZDDVSAWDQPZ-UHFFFAOYSA-L barium acetate Chemical compound [Ba+2].CC([O-])=O.CC([O-])=O ITHZDDVSAWDQPZ-UHFFFAOYSA-L 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000008901 benefit Effects 0.000 description 1
- 239000006227 byproduct Substances 0.000 description 1
- FJDQFPXHSGXQBY-UHFFFAOYSA-L caesium carbonate Chemical compound [Cs+].[Cs+].[O-]C([O-])=O FJDQFPXHSGXQBY-UHFFFAOYSA-L 0.000 description 1
- 229910000024 caesium carbonate Inorganic materials 0.000 description 1
- AIYUHDOJVYHVIT-UHFFFAOYSA-M caesium chloride Chemical compound [Cl-].[Cs+] AIYUHDOJVYHVIT-UHFFFAOYSA-M 0.000 description 1
- FLJPGEWQYJVDPF-UHFFFAOYSA-L caesium sulfate Chemical class [Cs+].[Cs+].[O-]S([O-])(=O)=O FLJPGEWQYJVDPF-UHFFFAOYSA-L 0.000 description 1
- 238000001354 calcination Methods 0.000 description 1
- 125000004432 carbon atom Chemical group C* 0.000 description 1
- VSQHTVCBHFZBOT-UHFFFAOYSA-M cesium;chlorate Chemical compound [Cs+].[O-]Cl(=O)=O VSQHTVCBHFZBOT-UHFFFAOYSA-M 0.000 description 1
- 238000000975 co-precipitation Methods 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 230000009849 deactivation Effects 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 239000010946 fine silver Substances 0.000 description 1
- 150000004675 formic acid derivatives Chemical class 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 239000011261 inert gas Substances 0.000 description 1
- 239000004310 lactic acid Substances 0.000 description 1
- 235000014655 lactic acid Nutrition 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- QSHDDOUJBYECFT-UHFFFAOYSA-N mercury Chemical compound [Hg] QSHDDOUJBYECFT-UHFFFAOYSA-N 0.000 description 1
- 229910052753 mercury Inorganic materials 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 229910052754 neon Inorganic materials 0.000 description 1
- GKAOGPIIYCISHV-UHFFFAOYSA-N neon atom Chemical compound [Ne] GKAOGPIIYCISHV-UHFFFAOYSA-N 0.000 description 1
- 239000012299 nitrogen atmosphere Substances 0.000 description 1
- JCXJVPUVTGWSNB-UHFFFAOYSA-N nitrogen dioxide Inorganic materials O=[N]=O JCXJVPUVTGWSNB-UHFFFAOYSA-N 0.000 description 1
- QJGQUHMNIGDVPM-UHFFFAOYSA-N nitrogen group Chemical group [N] QJGQUHMNIGDVPM-UHFFFAOYSA-N 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 239000008188 pellet Substances 0.000 description 1
- 230000000737 periodic effect Effects 0.000 description 1
- 239000002574 poison Substances 0.000 description 1
- 231100000614 poison Toxicity 0.000 description 1
- 125000002924 primary amino group Chemical group [H]N([H])* 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- 238000010926 purge Methods 0.000 description 1
- 239000000376 reactant Substances 0.000 description 1
- 230000007420 reactivation Effects 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- LMEWRZSPCQHBOB-UHFFFAOYSA-M silver;2-hydroxypropanoate Chemical compound [Ag+].CC(O)C([O-])=O LMEWRZSPCQHBOB-UHFFFAOYSA-M 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 239000011885 synergistic combination Substances 0.000 description 1
- 239000008096 xylene Substances 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
- B01J23/38—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals
- B01J23/48—Silver or gold
- B01J23/50—Silver
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
- B01J37/02—Impregnation, coating or precipitation
- B01J37/0201—Impregnation
- B01J37/0203—Impregnation the impregnation liquid containing organic compounds
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
- B01J37/08—Heat treatment
- B01J37/082—Decomposition and pyrolysis
- B01J37/086—Decomposition of an organometallic compound, a metal complex or a metal salt of a carboxylic acid
Definitions
- the present invention relates generally to a supported silver catalyst useful for the vapor-phase oxidation of ethylene to ethylene oxide. More particularly, the present invention relates to a method of preparing an improved supported silver catalyst post impregnated with cesium.
- Related Art The use of supported silver catalysts for the oxidation of ethylene to ethylene oxide has been long known in the art. Additionally, over the years various promoting metals have been added to further enhance performance. In particular, the use of alkali metals has been disclosed in various amounts and added by different methods. A very extensive review of the patent literature is given in G.B. No. 2,043,481A. Such disclosures have been somewhat inconsistent in their teachings, as can be seen by comparing U.S. Pat. No. 2,238,474 in which sodium and lithium hydroxides were suggested as promoters and potassium and cesium were shown to be poisons to U.S Pat. No. 2,671,764 where rubidium and cesium sulfates were suggested as promoting compounds.
- alkali metals were suggested generally in the earlier disclosures, it is also generally true that more recent workers in the field have considered potassium, rubidium, and cesium as the preferred alkali metals.
- the series of patents to Nielson, et al. in which these materials were used in small amounts co- deposited with the silver — U.S. Pat. Nos. 3,962,136; 4,010,115, and 4,012,425.
- Still more recently the art has emphasized synergistic combinations of the alkali metals. For example, see G.B. No. 2,043,481A cited above and U.S. Pat. Nos. 4,212,772 or 4,226,782.
- the alkali metals may be used to rejuvenate used catalysts, as for example U.S. Pat. Nos. 4,123,385; 4,033,903; 4,177,169; and 4,186,106.
- the art teaches that the alkali metals may be deposited either before the silver 96/04989 PC17US94/08950
- alkali metal was suggested to be in quite a wide range in the older art. It was often indicated that large quantities, e.g. up to several per cent of an alkali metal could be used. More recently, the art generally has taught that small quantities of alkali metals produce the optimum effect no matter when the silver and the alkali metals were deposited. Kilty in U.S. Pat. No. 4,207,210 related the optimum amount of alkali metal to the surface area of the support. Exceptions to the above include patents issued to ICI which teach the use of large amounts of sodium alone (G.B. No. 1,560,480) and potassium in combination with smaller amounts of rubidium and cesium (U.S. Pat. No. 4,226,782). However, the art generally teaches that the optimum will be found in substantially lower quantities, perhaps on the order of 50-500 ppm by weight.
- the "activated" catalyst is then impregnated with a cesium solution and dried in air at 130*C for 3 hours.
- the use of the inert atmosphere during the activation step produced a catalyst that was more selective, but much less stable, i.e., the catalyst lost its activity fairly quickly resulting in shorter run length for a given end of run temperature.
- Cesium now appears to be the preferred alkali metal.
- Various sources of cesium are catalogued in the prior art, for example, cesium hydroxide, cesium nitrate, cesium chloride, cesium chlorate, cesium bicarbonate, cesium carbonate, and other anion functionalities such as formates, acetates and the like.
- U.S. Pat. No. 4,374,260 discloses the coprecipitation of silver and cesium salt, such as the carbonate from a silver carboxylate/amino complex.
- U. S. Pat No's 4,350,616 and 4,389,338 both show the deposition of CsC0 3 onto activated silver catalyst from alcohol solution where the silver was derived from aqueous silver salt solution.
- U. S. Pat. No's 4,066,575 and 4,033,903 disclose the preparation of silver catalyst from both aqueous and non aqueous salt solutions and subsequent treatment of the activated silver catalyst with post deposition of an alkali metal salt such as cesium and anions including carbonate from lower alcohol and preferably from aqueous solutions.
- an alkali metal salt such as cesium and anions including carbonate from lower alcohol and preferably from aqueous solutions.
- U.S. Pat. No. 4,342,667 discloses the post deposition of cesium on to silver catalyst derived from aqueous solutions.
- the present preparation is characterized as being substantially anhydrous with post disposition of cesium.
- one aspect of the present invention is a catalyst prepared by the process of impregnating a porous support having a low surface area with a hydrocarbon solution of a silver salt of an organic acid which is substantially free of water and acid.
- the impregnated support is subjected to a low temperature activation in an atmosphere containing less oxygen than air, preferably an inert atmosphere, by heating at a temperature not exceeding 300*C preferably in the range of 250*C to SOO'C on a moving belt.
- the activation produces a support containing the activated silver.
- the catalyst is made by impregnating a porous support, preferably having a surface area in the range of 0.2 to 2.0 m 2 /g, with a hydrocarbon solution of a silver salt of an organic acid.
- the solution should be substantially free of both water and acid as this aspect has been shown to be especially beneficial to catalyst performance and hence preferred.
- the impregnated support is activated as described above.
- an alkali metal preferably cesium
- Stability as that term is used herein relates to the temperature in the catalyst bed in operation as a function of time (time trend) .
- the activated silver catalyst is an anhydrous post impregnated with an alkali metal, preferably cesium, to produce a finished catalyst by immersing the support in a circulating stream of the alkali metal in an anhydrous solvent such as ethanol.
- an alkali metal preferably cesium
- the optimum amount of alkali metal(s) added will be selected to optimize catalyst performance and will be dependent upon the surface area of the support chosen. That is, more alkali metal will be used on supports which have larger surface area than on those having relatively small surface area.
- the catalyst of the present invention may be employed under oxidizing conditions typical to the art for preparing ethylene oxide by the vapor phase oxidation of ethylene with improved results, especially catalyst stability.
- inert as used herein means any gaseous material under the conditions of activation which does not react with silver or any other component of the silver impregnated support.
- Preferred inert material include nitrogen, helium and carbon dioxide, but other specific material include neon, argon, and the like may be used.
- the limitation of oxygen during the activation is of principal concern.
- FIG. 1 is a scanning electron micrograph of a silver catalyst in which the silver was deposited by heating in air at 500'C.
- FIG. 2 is a scanning electron micrograph of a silver catalyst in which the silver was deposited by heating in air at 300"C.
- FIG. 3 is a scanning electron micrograph of a silver catalyst in which the silver was deposited by heating in an inert atmosphere at 500*C.
- FIG. 4 is a scanning electron micrograph of a silver catalyst in which the silver was deposited by heating in an inert atmosphere at 300 * C.
- FIG. 5 is a scanning electron micrograph of a silver catalyst in which the silver was deposited by heating in an inert atmosphere at 300 ⁇ C and thereafter used about 1000 hours in an ethylene oxide reactor.
- FIG. 6 is a scanning electron micrograph of a silver catalyst in which the silver was deposited by heating in air at 500"C and thereafter used about 1000 hours in an ethylene oxide reactor.
- the catalyst of the present invention may contain from 3 to 25 wt% silver on the support.
- Preferred catalysts prepared in accordance with this invention contain up to about 20% by weight of silver, expressed as metal, deposited upon the surface and throughout the pores of a porous refractory support. Silver contents higher than 20% by weight of total catalyst are effective, but result in catalysts which are unnecessarily expensive. Silver contents, expressed as metal, of about 5-13% based on weight of total catalyst are preferred, while silver contents of 8-12% are especially preferred.
- Catalysts may be made with supports comprising alumina, silica, silica-alumina or combinations thereof.
- Preferred supports are those containing principally alpha-alumina, particularly those containing up to about 15 wt% silica.
- Especially preferred supports have a porosity of about 0.1- 1.0 cc/g and preferably about 0.2-0.7 cc/g.
- Preferred supports also have a relatively low surface area, i.e. about 0.2-2.0 m 2 /g, preferably 0.4-1.6 m 2 /g and most preferably 0.5-1.3 m 2 /g as determined by the BET method. See J. A. Chem. Soc. 60, 309-16 (1938) . Porosities are determined by the mercury porosimeter method; see Drake and Ritter, "Ind. Eng. Chem. Anal. Ed.,” 17, 787 (1945). Pore and pore diameter distributions are determined from the surface area and apparent porosity measurements.
- the supports are desirably formed into regularly shaped pellets, spheres, rings, etc.
- the support particles used have "equivalent diameters" in the range from 3-10 mm and preferably in the rang of 4-8 mm, which are usually compatible with the internal diameter of the tubes in which the catalyst is placed. "Equivalent diameter” is the diameter of a sphere having the same external surface (i.e. neglecting surface within the pores of the particle) to volume ratio as the support particles being employed.
- the silver is added to the support by immersion of the support into a solution containing a silver salt of an organic acid which is substantially free of water and said acid.
- the silver containing liquid penetrates by absorption, capillary action and/or vacuum into the pores of the support.
- a single immersion or a series of immersions, with or without intermediate drying, may be used, depending in part upon the concentration of the silver salt in the solution.
- suitable impregnating solutions will generally contain from 5-50 wt% silver, expressed as metal, but supplied as silver salts of acids. The exact concentrations employed, of course, will depend upon, among other factors, the desired silver content, the nature of the support, the viscosity of the liquid, and solubility of the acid silver salt.
- Impregnation of the selected support is achieved in a conventional manner.
- the support material is placed in the silver solution until all of the solution is absorbed by the support.
- the quantity of the silver solution used to impregnate the porous support is no more than is necessary to fill the pore volume of the porous support.
- the impregnating solution is characterized as a substantially water free and acid free organic solution of a silver salt of an organic acid, such as the neo acids (particularly those having at least seven carbon atoms) disclosed in U.S. Patent No. 4,864,042 which is incorporated herein in its entirety.
- a hydrocarbon solvent is employed, such as toluene, cyclohexane, xylene, ethyl benzene, cumene or nonene which would normally be water free. Since water is considered to be detrimental to the preparation of silver catalysts when the method of the invention is used, it should be present in no more than about 0.1 vol% in the silver impregnating solution, preferably less than about 0.01 vol%.
- the support is then activated in the low temperature process as described, preferably on a moving belt in the atmosphere as specified.
- the silver impregnated support is activated in an inert atmosphere such as nitrogen, carbon dioxide or helium, at a temperature below 300*C as recited and for limited periods, preferably of from about one to ten minutes.
- the support may be impregnated with the alkali metal if desired. It is the purpose of alkali metal to modify the catalyst and raise selectivity while leaving the improved stability intact. When used the amount of the alkali metal on the finished catalyst is generally similar to those employed heretofore.
- the alkali metals of the periodic table include sodium, lithium, potassium, rubidium and cesium. For purposes of the present invention, the latter three alkali metals are particularly preferred, especially cesium, although sodium and lithium are not necessarily excluded.
- the alkali metal salts are dissolved in alcohol solutions, preferably substantially free of water.
- the improvement from the use of cesium salt in a pure alcohol solvent, substantially free of water is believed to relate to the relatively poor solubility of cesium salt in alcohol.
- the cesium compound although poorly soluble, remains evenly distributed through the solvent during evaporization and drying, hence is more evenly distributed over the silver catalyst.
- Active catalyst may also be obtained when using the present activation followed by deposition of cesium from alcohol-solution.
- the alkali metal impregnated catalysts are dried rapidly, e.g. one to two minutes at high temperature, e.g. at least 100 * C up to 800*C, preferably around 200 * C to 600 "C. This may be readily achieved by using a moving belt as described herein. The drying may be conducted in air or an inert gas.
- Catalysts prepared by the procedures above have improved performance, especially stability, for use in the production of ethylene oxide by the vapor phase oxidation of ethylene with molecular oxygen. These usually involve reaction temperatures of about 150"C to 400°C, usually about 200"C to 300"C, and reaction pressures in the range of from 0.5 to 35 bar.
- Reactant feed mixtures contain 0.5 to 20 % ethylene and 3 to 15 % oxygen, with the balance comprising comparatively inert materials including such substances as nitrogen, carbon dioxide, methane, ethane, argon and the like.
- the catalyst prepared by the process of the present invention has a different silver particle size and dispersion than catalysts prepared by conventional processes.
- the support impregnated with the silver solution is subjected to an elevated temperature in the presence of a gas containing oxygen, normally air. This results in very fine silver particles and is shown in FIG.
- the catalysts with the finer silver particle dispersion lose their selectivity during use (over about 1000 hours) .
- the same catalysts having the 110-125 pp ⁇ 2 initial dispersion end up with a silver dispersion of about 1-2 pp ⁇ 2 as shown in FIG. 5 which is a SEM of a catalyst having an initial dispersion of 110-125 pp ⁇ 2 after about 1000 hours in an ethylene oxide reactor.
- a catalyst having the lower initial dispersion of about 10-25 pp ⁇ 2 ends up with a silver particle dispersion of 25 pp ⁇ 2 as shown in FIG. 6.
- the finished catalysts are then tested for activity and selectivity by crushing and placing 36 grams in a micro reactor consisting of a 1/4 inch stainless steel tube which is heated in a salt bath.
- a feed mixture of 7% oxygen, 8% C0 2 , 15% C 2 H , 70% N 2 is passed over the catalyst with a gas space velocity of 5500 hr -1 .
- the pressure is maintained at 300 psig (21.69 bar) and the temperature between 200*C and 300 ⁇ C as required to maintain an outlet concentration of 1.5 vol% (160 Kg per hour per m 3 of catalyst) ethylene oxide.
- the activity of the catalyst is expressed as the temperature necessary to maintain the outlet concentration at 1.50 vol% ethylene oxide, the lower the temperature, the more active the catalyst.
- the selectivity of the catalyst is expressed as the mole% of the total ethylene converted to ethylene oxide at the outlet concentration of 1.50 vol% ethylene.
- the stability of the catalyst is measured by the increase in temperature required to maintain the ethylene oxide productivity.
- the support used for this preparation was obtained from Norton Company and was made primarily of ⁇ -alumina in the form of 5/16 inch cylinders.
- the support has a surface area of 0.55 m 2 /g, pore volume of .3 cc/g, and medium pore diameter of 1.5 ⁇ .
- the deposition of the silver was induced by heating the impregnated support to a temperature that did not exceed 300° on a moving belt in a stream of nitrogen.
- the residence time of the catalyst in the heated zone was two minutes.
- the catalyst was then impregnated for two hours at room temperature in an anhydrous ethanolic solution that contained 525 ppm cesium bicarbonate.
- the catalyst was superficially dried by a stream of nitrogen followed by heating on a moving belt at 200*C.
- a catalyst was prepared in substantially the same manner and using the same support as Example 1 except that the initial calcination was carried out in a gas stream of nitrogen containing 2.5% oxygen. After 100 hours in the reactor the selectivity was 82.0% and the reactor temperature was 228*C.
- EXAMPLE 3 (Comparative) The support used for this preparation was obtained from Norton Company and was made primarily of ⁇ -alumina in the form of 5/16 inch cylinders. The support has a surface area of 0.55 m 2 /g, pore volume of .3 cc/g, and medium pore diameter of 1.5 ⁇ . A 95 parts of a cumene solution of silver neodecanoate, containing 26 wt% silver, was added to 225 parts of the hot support and the mixture was mixed for 20 minutes. The catalyst was prepared using activation with air at 500 ' C and was impregnated with cesium hydroxide solution in water/alcohol solvent, which was subsequently dried with vacuum. The catalyst was tested under the same condition as in example 1. After 150 hours of reaction time the selectivity to ethylene oxide was 80.9% and the reaction temperature was 232*C. The catalyst's performance did not improve with longer reaction time.
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Abstract
Priority Applications (7)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB9606642A GB2297278B (en) | 1994-08-09 | 1994-08-09 | Process for preparing silver catalyst |
AU75583/94A AU7558394A (en) | 1994-08-09 | 1994-08-09 | Process for preparing silver catalyst |
DE4481119T DE4481119T1 (de) | 1994-08-09 | 1994-08-09 | Verfahren zur Herstellung eines Silberkatalysators |
JP50724896A JP3748888B2 (ja) | 1994-08-09 | 1994-08-09 | 銀触媒の調製法 |
NL9420033A NL9420033A (nl) | 1994-08-09 | 1994-08-09 | Werkwijze voor de bereiding van een zilver-katalysator. |
CA002196059A CA2196059C (fr) | 1994-08-09 | 1994-08-09 | Procede de preparation d'un catalyseur a base d'argent |
PCT/US1994/008950 WO1996004989A1 (fr) | 1994-08-09 | 1994-08-09 | Procede de preparation d'un catalyseur a base d'argent |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
PCT/US1994/008950 WO1996004989A1 (fr) | 1994-08-09 | 1994-08-09 | Procede de preparation d'un catalyseur a base d'argent |
Publications (1)
Publication Number | Publication Date |
---|---|
WO1996004989A1 true WO1996004989A1 (fr) | 1996-02-22 |
Family
ID=36032145
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/US1994/008950 WO1996004989A1 (fr) | 1994-08-09 | 1994-08-09 | Procede de preparation d'un catalyseur a base d'argent |
Country Status (7)
Country | Link |
---|---|
JP (1) | JP3748888B2 (fr) |
AU (1) | AU7558394A (fr) |
CA (1) | CA2196059C (fr) |
DE (1) | DE4481119T1 (fr) |
GB (1) | GB2297278B (fr) |
NL (1) | NL9420033A (fr) |
WO (1) | WO1996004989A1 (fr) |
Cited By (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2004002954A3 (fr) * | 2002-06-28 | 2004-08-19 | Shell Oil Co | Procede permettant d'ameliorer la selectivite d'un catalyseur, et processus d'epoxydation d'une olefine |
US7102022B2 (en) | 2002-06-28 | 2006-09-05 | Shell Oil Company | Method for the start-up of an epoxidation process and a process for the epoxidation of an olefin |
WO2006133183A3 (fr) * | 2005-06-07 | 2007-08-09 | Shell Oil Co | Catalyseur, procede de preparation de ce catalyseur, et procede pour produire un oxyde d'olefine, un 1,2-diol, un ether de 1,2-diol, ou une alcanolamine |
US7348444B2 (en) | 2003-04-07 | 2008-03-25 | Shell Oil Company | Process for the production of an olefin oxide |
US20110094120A1 (en) * | 2009-10-28 | 2011-04-28 | The Dow Chemical Company | Device to dry catalyst roaster conveyor belt and method of using same |
US8008515B2 (en) | 2006-05-02 | 2011-08-30 | Nippon Shokubai Co., Ltd. | Catalyst for partial oxidation of olefin, preparation method thereof, and process for preparing alkylene oxide |
US8148555B2 (en) | 2003-06-26 | 2012-04-03 | Shell Oil Company | Method for improving the selectivity of a catalyst and a process for the epoxidation of an olefin |
US8921586B2 (en) | 2008-05-07 | 2014-12-30 | Shell Oil Company | Process for the production of an olefin oxide, a 1,2-diol, a 1,2-diol ether, a 1,2-carbonate, or an alkanolamine |
US9346774B2 (en) | 2008-05-07 | 2016-05-24 | Shell Oil Company | Process for the start-up of an epoxidation process, a process for the production of ethylene oxide, a 1,2-diol, a 1,2-diol ether, a 1,2-carbonate, or an alkanolamine |
US10532989B2 (en) | 2007-05-09 | 2020-01-14 | Shell Oil Company | Epoxidation catalyst, a process for preparing the catalyst, and a process for the production of an olefin oxide, a 1,2-diol, a 1,2-diol ether, a 1,2-carbonate, or an alkanolamine |
US11801493B2 (en) | 2016-12-02 | 2023-10-31 | Shell Usa, Inc. | Methods for conditioning an ethylene epoxidation catalyst and associated methods for the production of ethylene oxide |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
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BE1017795A3 (fr) * | 2005-12-22 | 2009-07-07 | Shell Int Research | Procede d'installation d'un catalyseur d'epoxydation dans un reacteur, procede de preparation d'un oxyde d'olefine ou d'un produit chimique derivable d'un oxyde d'olefine, et reacteur approprie pour un tel procede. |
US7459589B2 (en) | 2005-12-22 | 2008-12-02 | Shell Oil Company | Process for the preparation of an alkylene glycol |
US7750170B2 (en) | 2005-12-22 | 2010-07-06 | Shell Oil Company | Process for mixing an oxidant having explosive potential with a hydrocarbon |
TW201705868A (zh) * | 2015-07-01 | 2017-02-16 | 艾迪科股份有限公司 | 擔持體、乙烯去除劑及保鮮劑 |
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US4066575A (en) * | 1976-07-26 | 1978-01-03 | Halcon International, Inc. | Process for the preparation of a supported silver catalyst |
US4555501A (en) * | 1984-05-14 | 1985-11-26 | The Halcon Sd Group, Inc. | Process for preparing silver catalysts |
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FR2432023A2 (fr) * | 1978-04-28 | 1980-02-22 | Ugine Kuhlmann | Catalyseurs a base d'argent pour la production d''oxyde d'ethylene |
DE2914640C2 (de) * | 1979-04-11 | 1986-01-30 | Hüls AG, 4370 Marl | Verfahren zur Herstellung von Silberkatalysatoren für die Herstellung von Ethylenoxid |
DE3104207C2 (de) * | 1981-02-06 | 1984-11-29 | Grote & Hartmann Gmbh & Co Kg, 5600 Wuppertal | Elektrischer Steckverbinder |
GB8304749D0 (en) * | 1983-02-21 | 1983-03-23 | Ici Plc | Catalysts |
DE3528313A1 (de) * | 1985-08-07 | 1987-02-12 | Basf Ag | Silberkatalysator, seine herstellung und verwendung |
DE3905578A1 (de) * | 1989-02-23 | 1990-08-30 | Basf Ag | Verfahren zur herstellung eines silberkatalysators |
US6184175B1 (en) * | 1993-03-01 | 2001-02-06 | Scientic Design Company, Inc. | Process for preparing silver catalyst |
-
1994
- 1994-08-09 CA CA002196059A patent/CA2196059C/fr not_active Expired - Fee Related
- 1994-08-09 NL NL9420033A patent/NL9420033A/nl active Search and Examination
- 1994-08-09 WO PCT/US1994/008950 patent/WO1996004989A1/fr active Application Filing
- 1994-08-09 GB GB9606642A patent/GB2297278B/en not_active Expired - Fee Related
- 1994-08-09 AU AU75583/94A patent/AU7558394A/en not_active Abandoned
- 1994-08-09 JP JP50724896A patent/JP3748888B2/ja not_active Expired - Fee Related
- 1994-08-09 DE DE4481119T patent/DE4481119T1/de not_active Withdrawn
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
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US4066575A (en) * | 1976-07-26 | 1978-01-03 | Halcon International, Inc. | Process for the preparation of a supported silver catalyst |
US4555501A (en) * | 1984-05-14 | 1985-11-26 | The Halcon Sd Group, Inc. | Process for preparing silver catalysts |
Cited By (17)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2004002954A3 (fr) * | 2002-06-28 | 2004-08-19 | Shell Oil Co | Procede permettant d'ameliorer la selectivite d'un catalyseur, et processus d'epoxydation d'une olefine |
US7102022B2 (en) | 2002-06-28 | 2006-09-05 | Shell Oil Company | Method for the start-up of an epoxidation process and a process for the epoxidation of an olefin |
US7485597B2 (en) | 2002-06-28 | 2009-02-03 | Shell Oil Company | Method for improving the selectivity of a catalyst and a process for the epoxidation of an olefin |
KR100980123B1 (ko) | 2002-06-28 | 2010-09-03 | 셀 인터나쵸나아레 레사아치 마아츠샤피 비이부이 | 촉매 선택성을 향상시키는 방법 및 올레핀 에폭시화 방법 |
US7348444B2 (en) | 2003-04-07 | 2008-03-25 | Shell Oil Company | Process for the production of an olefin oxide |
US8148555B2 (en) | 2003-06-26 | 2012-04-03 | Shell Oil Company | Method for improving the selectivity of a catalyst and a process for the epoxidation of an olefin |
US8084390B2 (en) * | 2005-06-07 | 2011-12-27 | Shell Oil Company | Catalyst, a process for preparing the catalyst and a process for the production of an olefin oxide, a 1,2-diol, a 1,2 diol ether, or an alkanolamine |
WO2006133183A3 (fr) * | 2005-06-07 | 2007-08-09 | Shell Oil Co | Catalyseur, procede de preparation de ce catalyseur, et procede pour produire un oxyde d'olefine, un 1,2-diol, un ether de 1,2-diol, ou une alcanolamine |
US8357825B2 (en) | 2005-06-07 | 2013-01-22 | Shell Oil Company | Process for the production of a 1,2-diol, a 1,2-diol ether, or an alkanolamine |
US8357813B2 (en) | 2005-06-07 | 2013-01-22 | Shell Oil Company | Process for the production of an olefin oxide |
US8008515B2 (en) | 2006-05-02 | 2011-08-30 | Nippon Shokubai Co., Ltd. | Catalyst for partial oxidation of olefin, preparation method thereof, and process for preparing alkylene oxide |
US10532989B2 (en) | 2007-05-09 | 2020-01-14 | Shell Oil Company | Epoxidation catalyst, a process for preparing the catalyst, and a process for the production of an olefin oxide, a 1,2-diol, a 1,2-diol ether, a 1,2-carbonate, or an alkanolamine |
US8921586B2 (en) | 2008-05-07 | 2014-12-30 | Shell Oil Company | Process for the production of an olefin oxide, a 1,2-diol, a 1,2-diol ether, a 1,2-carbonate, or an alkanolamine |
US9346774B2 (en) | 2008-05-07 | 2016-05-24 | Shell Oil Company | Process for the start-up of an epoxidation process, a process for the production of ethylene oxide, a 1,2-diol, a 1,2-diol ether, a 1,2-carbonate, or an alkanolamine |
US20110094120A1 (en) * | 2009-10-28 | 2011-04-28 | The Dow Chemical Company | Device to dry catalyst roaster conveyor belt and method of using same |
US8567099B2 (en) * | 2009-10-28 | 2013-10-29 | Dow Technology Investments Llc | Device to dry catalyst roaster conveyor belt and method of using same |
US11801493B2 (en) | 2016-12-02 | 2023-10-31 | Shell Usa, Inc. | Methods for conditioning an ethylene epoxidation catalyst and associated methods for the production of ethylene oxide |
Also Published As
Publication number | Publication date |
---|---|
JPH10503709A (ja) | 1998-04-07 |
GB2297278B (en) | 1998-05-20 |
DE4481119T1 (de) | 1996-11-21 |
NL9420033A (nl) | 1996-06-03 |
GB2297278A (en) | 1996-07-31 |
CA2196059A1 (fr) | 1996-02-22 |
JP3748888B2 (ja) | 2006-02-22 |
CA2196059C (fr) | 2004-11-16 |
AU7558394A (en) | 1996-03-07 |
GB9606642D0 (en) | 1996-06-05 |
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