GB2199588A - Process for the selective hydrogenation of acetylenes - Google Patents
Process for the selective hydrogenation of acetylenes Download PDFInfo
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- GB2199588A GB2199588A GB08631017A GB8631017A GB2199588A GB 2199588 A GB2199588 A GB 2199588A GB 08631017 A GB08631017 A GB 08631017A GB 8631017 A GB8631017 A GB 8631017A GB 2199588 A GB2199588 A GB 2199588A
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- process according
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- hydrogen
- alkynes
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- 238000000034 method Methods 0.000 title claims description 41
- 238000005984 hydrogenation reaction Methods 0.000 title claims description 36
- 125000002534 ethynyl group Chemical class [H]C#C* 0.000 title description 2
- 239000003054 catalyst Substances 0.000 claims description 75
- KAKZBPTYRLMSJV-UHFFFAOYSA-N Butadiene Chemical compound C=CC=C KAKZBPTYRLMSJV-UHFFFAOYSA-N 0.000 claims description 66
- KDLHZDBZIXYQEI-UHFFFAOYSA-N Palladium Chemical compound [Pd] KDLHZDBZIXYQEI-UHFFFAOYSA-N 0.000 claims description 42
- 239000001257 hydrogen Substances 0.000 claims description 38
- 229910052739 hydrogen Inorganic materials 0.000 claims description 38
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims description 37
- 150000001345 alkine derivatives Chemical class 0.000 claims description 31
- 229910052763 palladium Inorganic materials 0.000 claims description 20
- 239000007788 liquid Substances 0.000 claims description 17
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 claims description 15
- 229910052751 metal Inorganic materials 0.000 claims description 8
- 239000002184 metal Substances 0.000 claims description 8
- 229910001020 Au alloy Inorganic materials 0.000 claims 1
- 239000003353 gold alloy Substances 0.000 claims 1
- JUWSSMXCCAMYGX-UHFFFAOYSA-N gold platinum Chemical compound [Pt].[Au] JUWSSMXCCAMYGX-UHFFFAOYSA-N 0.000 claims 1
- KDKYADYSIPSCCQ-UHFFFAOYSA-N but-1-yne Chemical group CCC#C KDKYADYSIPSCCQ-UHFFFAOYSA-N 0.000 description 20
- 229930195733 hydrocarbon Natural products 0.000 description 18
- 150000002430 hydrocarbons Chemical class 0.000 description 18
- 239000000203 mixture Substances 0.000 description 12
- WFYPICNXBKQZGB-UHFFFAOYSA-N butenyne Chemical group C=CC#C WFYPICNXBKQZGB-UHFFFAOYSA-N 0.000 description 11
- 125000000383 tetramethylene group Chemical group [H]C([H])([*:1])C([H])([H])C([H])([H])C([H])([H])[*:2] 0.000 description 10
- 150000000475 acetylene derivatives Chemical class 0.000 description 9
- 239000004215 Carbon black (E152) Substances 0.000 description 8
- 239000000243 solution Substances 0.000 description 8
- 235000013844 butane Nutrition 0.000 description 7
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 6
- 230000004913 activation Effects 0.000 description 6
- 239000010931 gold Substances 0.000 description 6
- 238000002347 injection Methods 0.000 description 6
- 239000007924 injection Substances 0.000 description 6
- 238000002474 experimental method Methods 0.000 description 5
- 239000011148 porous material Substances 0.000 description 5
- 238000011069 regeneration method Methods 0.000 description 5
- 238000006243 chemical reaction Methods 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- -1 ethyl up to 5% Chemical class 0.000 description 4
- 239000007791 liquid phase Substances 0.000 description 4
- IJDNQMDRQITEOD-UHFFFAOYSA-N n-butane Chemical class CCCC IJDNQMDRQITEOD-UHFFFAOYSA-N 0.000 description 4
- 238000004230 steam cracking Methods 0.000 description 4
- UHOVQNZJYSORNB-UHFFFAOYSA-N Benzene Chemical compound C1=CC=CC=C1 UHOVQNZJYSORNB-UHFFFAOYSA-N 0.000 description 3
- 238000001816 cooling Methods 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 150000002739 metals Chemical class 0.000 description 3
- 229910052757 nitrogen Inorganic materials 0.000 description 3
- 238000006116 polymerization reaction Methods 0.000 description 3
- MWWATHDPGQKSAR-UHFFFAOYSA-N propyne Chemical group CC#C MWWATHDPGQKSAR-UHFFFAOYSA-N 0.000 description 3
- 229920003051 synthetic elastomer Polymers 0.000 description 3
- 239000005061 synthetic rubber Substances 0.000 description 3
- 239000007864 aqueous solution Substances 0.000 description 2
- 238000001514 detection method Methods 0.000 description 2
- 150000001993 dienes Chemical class 0.000 description 2
- 229910052737 gold Inorganic materials 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 238000005470 impregnation Methods 0.000 description 2
- 230000007774 longterm Effects 0.000 description 2
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 2
- 238000002360 preparation method Methods 0.000 description 2
- 230000008929 regeneration Effects 0.000 description 2
- 238000009834 vaporization Methods 0.000 description 2
- 230000008016 vaporization Effects 0.000 description 2
- 125000000391 vinyl group Chemical group [H]C([*])=C([H])[H] 0.000 description 2
- 229920002554 vinyl polymer Polymers 0.000 description 2
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 description 1
- 229910000570 Cupronickel Inorganic materials 0.000 description 1
- 229910017974 NH40H Inorganic materials 0.000 description 1
- HSFWRNGVRCDJHI-UHFFFAOYSA-N alpha-acetylene Natural products C#C HSFWRNGVRCDJHI-UHFFFAOYSA-N 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- YOCUPQPZWBBYIX-UHFFFAOYSA-N copper nickel Chemical compound [Ni].[Cu] YOCUPQPZWBBYIX-UHFFFAOYSA-N 0.000 description 1
- 229910052593 corundum Inorganic materials 0.000 description 1
- 125000001495 ethyl group Chemical group [H]C([H])([H])C([H])([H])* 0.000 description 1
- 239000007792 gaseous phase Substances 0.000 description 1
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 description 1
- 229910001385 heavy metal Inorganic materials 0.000 description 1
- 239000007970 homogeneous dispersion Substances 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 238000010338 mechanical breakdown Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000006384 oligomerization reaction Methods 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- JKDRQYIYVJVOPF-FDGPNNRMSA-L palladium(ii) acetylacetonate Chemical compound [Pd+2].C\C([O-])=C\C(C)=O.C\C([O-])=C\C(C)=O JKDRQYIYVJVOPF-FDGPNNRMSA-L 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 239000008188 pellet Substances 0.000 description 1
- 239000012071 phase Substances 0.000 description 1
- 239000002574 poison Substances 0.000 description 1
- 231100000614 poison Toxicity 0.000 description 1
- 239000010970 precious metal Substances 0.000 description 1
- QQONPFPTGQHPMA-UHFFFAOYSA-N propylene Natural products CC=C QQONPFPTGQHPMA-UHFFFAOYSA-N 0.000 description 1
- 125000004805 propylene group Chemical group [H]C([H])([H])C([H])([*:1])C([H])([H])[*:2] 0.000 description 1
- 238000010926 purge Methods 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
- 229910001845 yogo sapphire Inorganic materials 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
- B01J23/52—Gold
-
- 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
- B01J23/40—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals of the platinum group metals
- B01J23/44—Palladium
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C5/00—Preparation of hydrocarbons from hydrocarbons containing the same number of carbon atoms
- C07C5/02—Preparation of hydrocarbons from hydrocarbons containing the same number of carbon atoms by hydrogenation
- C07C5/08—Preparation of hydrocarbons from hydrocarbons containing the same number of carbon atoms by hydrogenation of carbon-to-carbon triple bonds
-
- 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
- B01J37/06—Washing
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C2523/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group C07C2521/00
- C07C2523/38—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group C07C2521/00 of noble metals
- C07C2523/40—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group C07C2521/00 of noble metals of the platinum group metals
- C07C2523/44—Palladium
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)
- Production Of Liquid Hydrocarbon Mixture For Refining Petroleum (AREA)
Description
I- 2199588 PROCESS FOR THE SELECTIVE HYDROGENATION OF ACETYLENES The
present invention relates to an improved process for removing alkynes from liquid hydrocarbon streams with a minimum loss of conjugated dienes present therein. More specifically, the invention relates to the selective hydrogenation of the alkynes present in the 1,3-butadiene-rich G4 cuts from the steam cracking units and mainly used for the production of synthetic rubber.
The polymerization of 1,3-butadiene to produce synthetic rubber is an important industrial process, some 10 million tons being produced annually. The typical feedstocks.used contain a major proportion of 1,3butadiene and butenes, but they also contain significant amounts of alkynes (also called acetylenes),',mainly vinylacetylene. As acetylenes act as a catalyst poison in the polymerization, they should be removed as completely as possible. Accordingly, it is usual to selectively hydrogenate the acetylenic compounds while trying to avoid or to limit losses in 1,3-butadiene.
The selectivity requirements for the process are high, since all other reactions should be avoided or prevented as much as possible. Said reactions obviously include the hydrogenation of 1,3-butadiene and butenes, but also polymerization reactions which reduce the catalyst life. Regenerations of the catalyst are possible, but the frequence thereof is 2 economically important, while they induce catalyst modifications and eventually mechanical breakdown of the catalyst pellets which results in higher pressure drops across the bed.
It has long been known to selectively hydrogenate at high temperature in vapour phase over a copper-nickel catalyst on a Si02/Al2O3 support. However, such processes are increasingly being abandoned because the catalyst has to be replaced or regenerated frequently, while the 1,3butadiene loss and the residual acetylenes concentration are presently considered as being too important.
U.S. Patent 4,493,906 discloses a catalyst for the removal of acetylenes from liquid hydrocarbon streams, said catalyst consisting essentially of finely divided Cu metal dispersed on a well-defined gamma alumina (which may contain up to 35 wt % of alpha alumina). The gamma alumina used has a surface area of 68-350 m2/g; 40-98% of the pores have a pore diameter of 4-12 nm, and 2-25% have a pore diameter between 100 and 1000 nm. The support is of high purity, with silicon less than 0.15 wt % as Si02 and Na < 0.15 wt % as Na20. The catalyst of U.S. Patent 4,493,906 is claimed to leave 0 ppm acetylenics when used at about 68'C and with a LHSV (liquid hourly space velocity) lower than 1. However, the corresponding cycle life is of only 5 1/2 days; after 6 days, about 100 ppm acetylenes are detected in the effluent. Obviously, at higher values of LHSV, either the cycle life would be still shorter, or the acetylenes removal would not be complete.
Another type of catalysts is palladium-based. Palladium is, among the metals of Group VIII, the most active and selective metal for the hydrogenation of acetylenics. However, it is known in the art that two types of operating troubles are encountered:
1,3-butadiene losses are observed even at moderate conversion of alkynes; T and - Palladium losses often reduce the catalyst life, as clearly disclosed in Hydrocarbon Processing, March 1985, p. 52.
As time goes by, the severity of the steam cracking increases, and the C4 raw cuts thus contain increasing concentrations of alkvnes, up to 1 wt % or even higher. On the other hand, the requirements for the acetylenics concentration in the effluent from the selective hydrogenation are becoming more and more severe. There is accordingly a need in the art for an improved process for removing alkynes from liquid hydrocarbon streams with a minimum loss of conjugated dienes present therein.
The process of the present invention for the selective hydrogenation of the alkynes present in 1,3-butadiene-rich C4 cuts over a palladium-based catalyst comprises the steps of (i) providing a 1,3-butadiene-rich C4 cut; (ii) passing said cut in trickle mode over the catalyst bed in the presence of hydrogen; (M) separating the residual hydrogen from the remainder of the ef fl uent f rom step (i i); and (iv) recovering a 1,3-butadiene-rich feedstock.
Palladium-based catalysts which may be used in the process of the invention are well known in the art. A particularly preferred catalyst consists of active palladium metal desposited on a high purity alumina support.
The amount of palladium in the catalyst which includes a high purity alumina support is preferably 0.1 to 0.35 wt more preferably about 0.2 wt %. Advantageously, the alumina is of high purity and the concentration of heavy metals other than Pd is less than 0.05 wt %.
The surface area of the catalyst is oreferably 50-110 m2/g,mcre preferably 65-95 m2/g. The volume of the pores is Qreferablv 0.5 - 0.6 cm3/g. The catalyst is preferably in the form of Spheres of 2-4 rim size.
It has already been said that the acidity of the alumina influences the undesired oligomerization reactions, and that gamma-alumina should therefore be preferred to a conventional eta-alumina. However, this is not required by the process of the invention, because this concerns only the long-term stability, not the activity of the fresh or regenerated catalyst. Other types of alumina may also be used, such as Q-type alumina, that has been disclosed in Japanese Patent Application JP-58017835.
So-called stabilized or promoted palladium-based catalysts are well known, as e.g. the palladium-gold supported catalysts disclosed in European Patent EP-89,252. However, the activity of these catalysts is usually lower than that of palladium-based catalysts. Although not - i 1 wishing to be bound by a theory, this could be explained by a less homogeneous dispersion of the metals on the support, because it is almost impossible to obtain a controlled supported bimetallic catalyst at the low loading-levels used for industrial precious metals catalysts. Indeed, the carrier must be suitable for appropriate interaction between the metals, and a well dispersed bimetallic species must be obtained then maintained. The use of stabilized or promoted catalysts in the process of the invention is optional and will therefore depend on the activity and long-term stability requirements.
The activation, start-up and regeneration procedures of the palladiumbased catalysts are known in the art. The activation consists of (i) purging the oxygen using.nitrogen, and (ii) passing hydrogen under atmospheric pressure while gradually heating up to a level of about WC then cooling. The start-up procedure consists of slowly increasing the hydrogen pressure, then the feed and hydrogen flow rates, and finally the temperature. The regeneration procedure consists of passing steam under atmospheric pressure whilegradually increasing the temperature to about 400% then continuing to pass steam under atmospheric pressure at a temperature of about 400C during about two hours thereafter, and finally gradually adding upto several mol percent air to said steam. During the regeneration procedure, the catalyst temperature should not exceed about SOWC. The regeneration is complete when the C02 content at the exit is sufficiently low.
The prior art and the catalysts manufacturers recommend the following typical process conditions for the selective hydrogenation of vinyl and ethyl acetylene in a liquid 1,3butadiene-rich C4 cut, using palladiumbased catalysts - temperature;15-10C (inlet), - pressure: 0.5 MPa (5 bar) LHSV: 30 1/l.h-1 Fi/alkvnes molar ratio: 2:1 The typical results obtained with these conditions are - feed: 1,3- butadiene 50 vol. Z ethyl acetylene 0.2 vol. Z vinyl acetylene 1.2 vol. % balance = butenes - purified effluent: 500 ppm total alkynes 37 butadiene loss cycle life: 8-10 months The Applicant has unexpectedly found that the known palladiumbased catalysts are much more selective when used in trickle mode than in homogeneous liquid phase. The term 'Incre2sed selectivity", as used herein, means that, for a given feed, less 1,3-butadiene is lost for a given level of 21kynes hydrogen2tion. The term "trickle mode", 2S used herein, is defined as the operation under such conditions of temperature and pressure that cause the feed to pass as a mixed gaseous-liquid phase over the catalyst. The hydrogenation reaction being exothermal, it is usually more convenient to provide the feed in the liquid state, under conditions very near to the gaseous-liquid equilibrium.
The reactor may be either an isothermal reactor or an adiabatic reactor. In the latter case, the heat released by the hydrogenation reaction is compensated by the vaporization of part of the liquid phase. It is thus highly desirable in the case of an adiabatic reactor to have at the inlet enough feedstock in the liquid phase in order to absorb all the heat released by the hydrogenation reactions, and further to inject part of the feed in the liquid form along the axis of the reactor.
According-to an embodiment of the invention, a sufficient proportion of the feed, preferably up to about 20%,is injected in liquid form, at one or several places, preferably about half way, of the catalyst bed in an adiabatic reactor. Although not wishing to be bound by a theory, 'the Applicant believes that these injections possibly serve to maintain the trickle mode conditions constant throughout the adiabatic reactor.
t_ Considering that the gaseous phase is produced partially by the vaporization of the feed, the trickle mode is usually operated in cocurrent mode. Although it is possible to operate.in up-flow mode, the Applicant has found that it is highly preferable to operate in down-flow mode.
The hydrogen may be injected with the feed. However, it has also been found highly desirable to distribute part of the hydrogen injection along the axis of thareactor, e.g. at one or several places about half way of the catalyst bed. According to an embodiment of the invention, up to 30%, preferably up to about 15%, of the total hydrogen flow is injected at one or several places about half way of the catalyst bed in an adiabatic reactor. Although not wishing to be bound by a theory, the Applicant believes that these injections possibly serve to maintain the trickle mode conditions constantthroughout the adiabatic reactor.
With a 100% hydrogen flow, the total pressure should preferably be of from 0.4 to 0.9 MPa, most preferably of 0.6 to. 0.8 MPa. Thus, if refinery hydrogen is used in the process of the invention, said refinery hydrogen usually containing about 75% hydrogen and about 25% methane, the total pressure should preferably be slightly higher. - The reaction temperature (or inlet temperature if an adiabatic reactor is used) is adjusted with respect to the total pressure, in order to maintain the desired trickle mode operation. Within the preferred ranges, higher values of the pressure and temperature tend to impart a higher activity to the catalyst.
The LHSV to be used is easily determined by one skilled in the art, in view of the specifications for residual acetylenics (and/or 1,3-butadiene loss in the case of 1,3-butadiene-rich C4 cuts). For example, nearcomplete alkynes hydrogenation at the 1% concentration level in 1,3butadiene-rich C4 cuts using palladium-based catalysts usually requires a LHSV lower than 10, but the corresponding 1,3-butadiene loss is of about 8% or higher; lower 1,3-butadiene losses may be obtained with higher LHSV, but the hydrogenation of alkynes may not be complete.
The hydrogen/alkynes molar ratio is usually of from 2:1 to 20:1, preferably of 4:1 to 10:1, most preferably of about 6:1.
The C4 feeds that may be used in the process of the invention usually comprise a mixture of normally gaseous hydrocarbons - 1,3-butadiene 30-55%, typicaily 40-50% - 1,2-butadiene up to 2%, typically about 0.2 % alkynes (mainly ethyl up to 5%, typically up to 1.5% and vinyl acetylene) - C3 hydrocarbons and heavies - butanes - butenes traces up to 10%, typically up to 5% balance The feeds are usually obtained from the steam cracking unit. However, other feeds or feeds obtained from other sources may also be contemplated, as for example propylene-rich feeds containing methylacetylene as impurity, without departing from the scope of the invention.
The invention will now be illustrated by means of the following examples, which are not meant to be limitative.
$0 ExamDle 1 a. Catalyst preparation The aiumina support selected was under the form of spheres having a diameter of 2-4 mm, and a bulk density of 0.72 g/cm3.
The support was contacted with a solution of palladium acetylacetonate in benzene. The weight ratio support: solution was of 10:16. The Pd weight concentration in the solution was of 1350 ppmw before contacting the solution with the support, and of 100 ppmw after 8 hours of impregnation.
The impregnated support was filtered and dried at 120'C during 6 hours under an air flow. It was then heated at 300'C in a tubular over, first during 2 hours under an air flow, then, after a nitrogen flush, during a further 2 hours under an hydrogen flow.
After cooling, the catalyst contained 0.2 wt % of palladium.
b. Catalyst activation and start-up The catalyst was purged during one hour with nitrogen at a space velocity of 333 1/1.h. Hydrogen under atmospheric pressure was then passed over the catalyst at a space velocity of 200 1/1.h; the catalyst was then heated at WC during 0.5 hours, then at 93C during 2 hours, and finally cooled to 2WC.
The hydrogen flow was then increased to 333 1/1.h at a temperature of 26'C for 35 minutes. The hydrogen pressure was then slowly increased from atmospheric to 0.61 MPa (6.2 kg/cm2) and maintained for 45 minutes. The feed and hydrogen flow rates were then increased to one fourth of nominal, maintained for 50 minutes, increased to half of the nominal values, maintained for 15 minutes, and finally increased to nominal values while raising the temperature to 57'C at a heating rate of 10C/h.
11 - c. Alkynes selective hydrogenation The operating conditions were as follows - inlet temperature 57.5C - pressure (gauge) 0.61 MPa (6.2 kg/CM2) - feed LMV 14.2 1/1.h hydrogen: feed molar ratio 1:20 adiabatic reactor, operated in downflow mode.
The composition of the feed and of the treated effluent after 24 and 44 hours were as follows:
feed after 24 h after 44 h - 1,3-butadiene 44.63 41.82 42.01 wt vinylacetylene 7768 < 5 < 5 ppmw - ethyl acetylene 1882 10 10 ppmw butanes 3.92 4.33 4.04 wt % butenes 49.89 53.11 53.26 wt % - other hydrocarbons balance balance balance ExamDle 2 The process described in Example 1 was continuously operated during.for 438 hours since start-up, with feeds having a similar composition to that of Example 1 and containing from 7140 to 7768 ppmw of vinyl acetylene and from 1680 to 1882 ppmw of ethyl acetylene. The operating conditions were also similar to those of Example 1.
After 438 hours of continuous operation, the following compositions were determined feed effluent - 1,3-butadiene 46.95 44.34 wt % - vinyl acetylene 7250 < 5 ppmw - ethyl acetylene 1710 19 ppmw - butanes - butenes - other hydrocarbons Example 3 - 12 4.08 47.72 4.03 wt % 50.90 wt % balance balance The selective hydrogenation experiment of Example 1 was repeated with a feed having a slightly different composition. All experimental conditions were identical. except where mentioned in Table 1.
Table 1
Selective hydrogenation of alkynes at a MSV of 14.2, under a pressure of 0.61 MPa (6.2 kg/cm2) and with an hydrogen: feed molar ratio of 1: 20.
Feed Effluent A Effluent B Effluent C 50.8 57.5 70 liquid trickle gaseous Temperature Mode 0 C Composition 1,3-butadiene 46.99 44.23 44.47 43.50 wt % vinyl acetylene 7140 109 < 5 4260 ppMW ethyl acetylene 1680 282 78 1320 PPMW butanes 3.74 3.75 3.72 3.91 wt % butenes 47.89 51.60 51.41 51.58 wt % other hydrocarbons balance balance balance balance This example shows that the hydrogenation is most selective when using the process of the invention; i.e. the 1,3-butadiene loss and the residual acetylenes concentration are minimum for a certain pressure when the temperature is such that the hydrogenation is carried out in trickle mode.
C Example 4
The selective hydrogenation experiment of Example 1 was repeated (all conditions being identical, except where mentioned in Table 2), with the same feed as used in Example 3.
Table 2 Selective hydrogenation of alkynes at a temperature of 57% at a LH5V of 14.2 and with an hydrogen:feed molar ratio of 1:20.
Feed Effluent A Effluent B Effluent C Pressure 0.6 0.66 0.78 MPa Mode trickle trickle liquid ComiDosition 1,3-butadiene vinyl acetylene ethyl acetylene butanes 46.99 7140 1680 3.74 44.26 < 5 45 3.75 51.55 45.44 36 187 3.91 50.15 44.05 wt % 507 449 3.77 51.68 PPMW ppmw wt % butenes 47.89 wt % other hydrocarbons balance balance balance balance This example shows that, for a given temperature, the selectivity is improved when the pressure is such that the hydrogenation is carried out in trickle mode.
1:
E.xw..:-,le 5 The experiment of Example 4 was repeated at a lower temperature. The experimental data are shown in table 3. Table 3 Selective hydrogenation of alkynes at a temperature of 50.5'C, at a MSV of 14.2 and with an hydrogen:feed molar ratio of 1:20.
Feed Effluent A Effluent B Effluent C Effluent D Pressure Mode Composition 1,3-butadiene vinyl acetylene ethyl acetylene butanes 46.99 7140 1680 3.74 butenes 47.89 other hydrocarbons balance 0.48 trickle 44.36 < 5 26 3.75 51.54 balance 0.61 0.69 0.78 liquid liquid liquid 44.23 43.98 109 258 282 375 3.75 3.77 51.60 51.78 balance balance MPa 43.71 wt % 487 455 3.79 52.02 balance ppMW ppMW wt % wt % 1 c L, r Example 6
The selective hydrogenationexperiment of Example 1 was repeated (all conditions being identical, except where mentioned in Table 4) with two slightly different feeds at different values of MSV, as shown in Table 4.
Table 4 Selective hydrogenation of alkynes at a temperature of 57.8% under a pressure of 0.61 MPa, and with an hydrogen:feed molar ratio of 1:20.
Feed A Effluent A Feed B Effluent Bl Effluent B2 MSV 29.3 14.0 10.8 1/1.h Composition 1,3-butadiene vinyl acetylene ethyl acetylene butanes 46.64 7290 1770 3.66 44.06 < 5 84 3.71 3.56 3.56 butenes 48 31 51.86 49.76 53.58 other hydrocarbons balance balance balance balance not detd.) This-example shows that, under otherwise similar conditions, a lower MSV gives a lower residual concentration of vinyl and ethyl acetylenes at the eXDense of a greater loss of 1,3-butadiene.
45.21 7260 1810 42.48 wt % < 5 24 < 5 PPMW ppMW wt % wt % Exa=le 7 Two selective hydrogenations were carried out in the same reactor with the same feed, said reactor being operated (i) in the upflow mode and (ii) in the downflow mode (data from Table 4). All other conditions were identical to those of Example 1, except where mentioned in Table 5. Table 5 Selective hydrogenation of alkynes under a pressure of 0.61 MPa (6.2 kg/cm2), and with an hydrogen/feed molar ratio of 1:20.
Feed---- Upflow effluent Downflow effluent Temperature 58 57.8 'C MSV 14.3 14.0 1/1.h Composition 1,3-butadiene 46.64 43.61 44.31 wt % vinyl acetylene 7290 69 < 5 ppMW ethyl acetylene 1770 283 42 ppMW butanes 3.66 3.91 3.76 wt % butenes 48.31 52.22 51.52 wt % other hydrocarbons b alance balance balance lample 8 The selective hydrogenation experiment of Example 1 was repeated (all conditions being identical, except where mentioned in Table 6) with a C4 feed containing important amounts of methyl acetylene (MAC5.
- Table 6
Selective hydrogenation of alkynes at a temperature of 57.5% under a pressure of 0.625 MPa, with a LHSV of 14.2 and with an hydrogen feed molar ratio of 0.059.
Composition Feed Effluent 1,3-butadiene 44.63 42.00 wt % methyl acetylene 1140 < 5 (detection limit) ppMW vinyl acetylene 7768 < 5 (detection limit) ethyl acetylene 1182 26 PPMW butanes 3.92 n.d. wt % butenes 49.89 n.d. wt % other C3 h.c. 0.13 n.d. wt % C 5+ h.c. balance (n.d. = not determined) This example shows that the hydrogenation is selective for all acetylene. s.
- 18 Example 9
The selective hydrogenation experiment of Example 1 was repeated (all conditions being identical, except where mentioned in Table 7), with a feed of similar composition.
Table 7
Selective hydrogenation ol alkynes at a temperature of WC and under a pressure of 0.8 MPa, using refinery hydrogen having a H2 content of 74%.
Effluent A Effluent B Total-HSV Feed injection (i) a main inlet (ii) at side inlet half way of catalyst bed Total H2 = total feed Hydrogen injection i) at main inlet (ii) at side inlet half way of catalyst bed 0 % Vinyl acetylene < 5 Ethyl acetylene 47 1,3-butadiene loss 6.2 9.8 % 0% 0.072 % 10.2 1 of liquid feed per 1.h 91.2 % 8.8 % 0.075 molar ratio 86.7 % 13.3 % < 5 20 6.4 ppMW ppMW % of initial amount This example shows that the injection of small portions of the feed and of the hydrogen about half way of the catalyst bed is beneficial to the process of the invention.
1 Example 10 a. Catalyst preparation _A palladium catalyst was prepared as described in Example 1 under,a. It was then contacted with an aqueous solution of HAuC14. The weight ratio support: solution was of 10:18. The Au concentration in the solution was of 120 ppmw before contacting the solution with the support, and of less than.10 ppmw after 3 hours of impregnation.
The impregnated catalyst was filtered, dried, calcined and reduced as described in Example 1 under a for the palladium catalyst. After cooling., the catalyst was washed with a normal NH40H aqueous solution until no more chloride ions can be detected in the solution then rinsed with water and dried at 12WC during 1 hour. The resulting catalyst contained 0.2 wt % of palladium and 0.02 wt % of gold.
b. Catalyst activation and start-up The procedure used in Example 1 was used for activation and startup of the Pd-Au catalyst.
c. Alkynes selective hydrogenation The operating conditions and the results were as disclosed in Table 8---.
1 Table 8 Selective hydrogenation of alkynes over a Pd-Au catalyst, in an adiabatic reactor operated in down-flow mode with an hydrogen:feed molar ratio of 1:20.
Feed A B c D Temperature 59.0 57.5 58.1 57.8 OC Pressure 0.62 0.61 0.61 0.61 MPa MSV 14.1 13.8 13.7 13.6 1/1.h Loss of 1,3-butadiene -6.6% -6.8% -7.3% -9.2% of 46.99 wt % Vinyl acetylene 7140 <5 G <5 <5 PPMW Ethyl acetylene 1680 140 75 34 10 ppMW This example shows that, although the Pd-Anu catalysts allow to remove the acetylenes down to lower than 30 ppmw, they have a lesser selectivity than Pd catalysts as shown by the greater losses of 1,3butadiene observed with Pd-Au catalysts.
Example 11
A commercially available palladium-based catalyst, sold as Catalyst type GIRDLER G-68-G (United Catalysts, Louisville, Kentucky; SUd-Chemie, MUnchen, Germany) was used. It had the following properties as indicated by the manufacturer which are within the scope of this invention palladium - particles - bulk density surface area - pore volume in Example 1.
0.2 +/- 0.02 wt % on alumina 2-4 mm diameter spheres 0.7 kg/l 65 - 95 m2/g 0.5 - 0.6 ml/g The activation and start-up were carriedout as described The operating conditions for the selective hydrogenation were as follows adiabatic reactor, operated in downflow mode inlet temperature 57.7'C pressure - feed MSV 0.61 MPa (6.24 kg/cm2) 14.3 1/1.h - hydrogen:feed molar ratio 0.050 The feed and the treated effluent had the following composition feed effluent - 1,3-butadiene 45.22 42.38 wt % vinylacetylene 7.150 < 5 ppmw - ethylacetylene 1750 < 5 ppMW - butanes 3.58 3.84 wt % - butenes 49.79 53.28 wt % - other hydrocarbons balance balance The preferred embodiments of the present invention provide an improved process for removing alkynes from hydrocarbon streams, and also a process for removing alkynes from hydrocarbon streams down to less than 30 ppm.
The preferred embodiments of the present invention also provide a process for removing alkynes from hydrocarbon streams, wherein the catalyst life is greatly increased.
The preferred embodiments of the present invention further provide an improved process for removing alkynes from hydrocarbon streams with a minimum loss of the other components thereof.
The preferred embodiments of the present invention still further provide a process for the selective hydrogenation of the alkynes present in the 1, 3-butadiene-rich C4 cuts from the steam cracking units and mainly used for the production of synthetic rubber.
Claims (17)
- ClaimsProcess for the selective hydrogenation of the alkynes present in 1,3-butadiene-rich C4 cuts over a palladium-based catalyst, comprising the steps of (i) providing a 1,3-butadiene-rich C4 cut; (ii) passing said cut in trickle mode over the catalyst bed in the presence of hydrogen; (iii) separating the residual hydrogen from the remainder of the effluent from step (ii); and (iv) recovering a 1,3.-butadiene-rich feedstock.
- 2. Process according to Claim 1, wherein the hydrogen.:alkynes molar ratio is from 2:1 to 20:1.
- 3. Process according to Claim 2, wherein the hydrogen:alkynes ratio is from 4:1 to 1M.
- 4. Process according to Claim 3, wherein the hydrogen:alkynes ratio is about 6:1.
- 5. Process according to any foregoing Claim, wherein the pressure in step (ii) is from 0.4 to 0.9 MPa when using a 100% hydrogen flow.
- 6. Process according to Claim 5, wherein the pressure in step. (ii) is from 0.6 MPa to 0.8 MPa.
- 7. Process according to any foregoing Claim, wherein step (ii) i carried out in a adiabatic reactor.!
- S 8. Process according to any foregoing Claim, wherein a sufficient proportion of the feed is injected in liquid form at one or several places along the catalyst bed.
- 9. Process according to any foregoing Claim, wherein up to about 20% of the feed is injected in liquid form at one or several places about half way of the catalyst bed.
- 10. Process according to any foregoing Claim, wherein up to 30%, of the total hydrogen flow is injected at one or several places along the catalyst bed.
- 11. Process according to Claim 10, wherein up to about 15% of the total hydrogen flow is injected at one or several places along the catalyst bed.
- Process according to any foregoing Claim, wherein step (ii) is operated in down-flow mode.
- 13. Process according to any foregoing Claim, wherein the catalyst contains 0.1 to 0.35 wt % of active palladium metal deposited on high purity alumina.
- 14. Process according to Claim 13, wherein the catalyst contains about 0. 2 wt % active palladium metal.
- 15. Process according to Claim 13 or Claim 14, wherein the catalyst is stabilized by the use of a bimetallic catalyst.
- 16. Process according to Claim 15, wherein the catalyst is made of platinum-gold alloy deposited on high purity alumina.
- 17. Process for the selective hydrogenation of the alkynes present in 1,3butadiene-rich cuts over a palladium-based catalyst substantially as described in any one of Examples 1 to 11.Published 19IR8 '. rhe Patent Office, State House. 6671 High Holborn, London WC1R 4TP Further copies may be obtained from The Patent Office, Sales Branch, St Mary Cray, Orpington, Kent BRS 3RD. Printed by Multiplex techniques ltd. St Maxy Cray, Kent. Con. 1/87.
Priority Applications (9)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB8631017A GB2199588B (en) | 1986-12-30 | 1986-12-30 | Process for the selective hydrogenation of acetylenes |
DE3744086A DE3744086C2 (en) | 1986-12-30 | 1987-12-24 | Process for the selective hydrogenation of alkynes |
JP62328448A JP2560056B2 (en) | 1986-12-30 | 1987-12-26 | Method for selective hydrogenation of acetylenes |
FR878718223A FR2609023B1 (en) | 1986-12-30 | 1987-12-28 | PROCESS FOR THE SELECTIVE HYDROGENATION OF ACETYLENES |
NL8703157A NL8703157A (en) | 1986-12-30 | 1987-12-29 | PROCESS FOR THE SELECTIVE HYDROGENATION OF ACETYLENE. |
IT23273/87A IT1223624B (en) | 1986-12-30 | 1987-12-30 | PROCEDURE FOR THE SELECTIVE HYDROGENATION OF ACETYLENS |
BE8701501A BE1000871A4 (en) | 1986-12-30 | 1987-12-30 | Process for selective hydrogenation acetylenic. |
CA000555579A CA1290354C (en) | 1986-12-30 | 1987-12-30 | Process for the selective hydrogenation of alkynes |
FI875774A FI87453C (en) | 1986-12-30 | 1987-12-30 | Process for selective hydrogenation of acetylenes |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB8631017A GB2199588B (en) | 1986-12-30 | 1986-12-30 | Process for the selective hydrogenation of acetylenes |
Publications (3)
Publication Number | Publication Date |
---|---|
GB8631017D0 GB8631017D0 (en) | 1987-02-04 |
GB2199588A true GB2199588A (en) | 1988-07-13 |
GB2199588B GB2199588B (en) | 1990-12-05 |
Family
ID=10609665
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB8631017A Expired - Fee Related GB2199588B (en) | 1986-12-30 | 1986-12-30 | Process for the selective hydrogenation of acetylenes |
Country Status (9)
Country | Link |
---|---|
JP (1) | JP2560056B2 (en) |
BE (1) | BE1000871A4 (en) |
CA (1) | CA1290354C (en) |
DE (1) | DE3744086C2 (en) |
FI (1) | FI87453C (en) |
FR (1) | FR2609023B1 (en) |
GB (1) | GB2199588B (en) |
IT (1) | IT1223624B (en) |
NL (1) | NL8703157A (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6509292B1 (en) | 2001-03-30 | 2003-01-21 | Sud-Chemie Inc. | Process for selective hydrogenation of acetylene in an ethylene purification process |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
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DE19500366C1 (en) * | 1995-01-09 | 1996-05-02 | Basf Ag | Supported palladium catalysts prepd. from palladium sol |
DE102008043344A1 (en) | 2008-10-31 | 2010-05-06 | Evonik Oxeno Gmbh | Preparing 1-alkoxy-2,7-diene, useful as starting material in synthesis of e.g. 1-octanol, comprises reacting 1,3-butadiene or 1,3-butadiene containing hydrocarbon mixture with alcohol or its mixture using palladium-carbene complex catalyst |
Citations (11)
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GB1063378A (en) * | 1963-07-10 | 1967-03-30 | Huels Chemische Werke Ag | Process for the removal of methylacetylene and propadiene from hydrocarbon mixtures |
GB1122018A (en) * | 1964-11-14 | 1968-07-31 | Huels Chemische Werke Ag | Removing butadiene and/or acetylenes from hydrocarbon mixtures |
GB1126848A (en) * | 1966-06-15 | 1968-09-11 | Bayer Ag | Process for the treatment by hydrogenation of c-hydrocarbons containing butadiene and n-but-1-ene |
US3859377A (en) * | 1973-12-13 | 1975-01-07 | Monsanto Co | Selective hydrogenation of c' 4 'acetylenic hydrocarbons |
US3898298A (en) * | 1973-04-13 | 1975-08-05 | Atlantic Richfield Co | Selective hydrogenation of vinyl acetylene |
GB1424288A (en) * | 1973-01-02 | 1976-02-11 | Monsanto Co | Elective hydrogenation process |
US4247725A (en) * | 1978-04-21 | 1981-01-27 | Nippon Oil Company, Ltd. | Method of removing acetylenes from C4 -hydrocarbon mixture containing butadiene |
GB2018817B (en) * | 1978-04-05 | 1982-07-07 | Inst Francais Du Petrole | Selective hydrogenation of hydrocarbons |
GB2053959B (en) * | 1979-07-06 | 1983-04-20 | Inst Francais Du Petrole | Purification of aromatic hydrocarbon cuts |
EP0081041A1 (en) * | 1981-11-04 | 1983-06-15 | Hüls Aktiengesellschaft | Process for the selective hydrogenation of polyunsaturated hydrocarbons in mixtures of hydrocarbons |
EP0087980A1 (en) * | 1982-03-02 | 1983-09-07 | Sumitomo Chemical Company, Limited | Method of selective hydrogenation of hydrocarbons |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
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GB510343A (en) * | 1936-10-22 | 1939-07-26 | Ig Farbenindustrie Ag | A process of hydrogenating monovinylacetylene |
FR1217305A (en) * | 1957-12-17 | 1960-05-03 | Bayer Ag | Process for removing acetylene, methylacetylene and allene from hydrocarbon mixtures |
US4247745A (en) * | 1978-09-13 | 1981-01-27 | Westinghouse Electric Corp. | Vacuum-type contactor assembly |
-
1986
- 1986-12-30 GB GB8631017A patent/GB2199588B/en not_active Expired - Fee Related
-
1987
- 1987-12-24 DE DE3744086A patent/DE3744086C2/en not_active Revoked
- 1987-12-26 JP JP62328448A patent/JP2560056B2/en not_active Expired - Lifetime
- 1987-12-28 FR FR878718223A patent/FR2609023B1/en not_active Expired
- 1987-12-29 NL NL8703157A patent/NL8703157A/en active Search and Examination
- 1987-12-30 FI FI875774A patent/FI87453C/en not_active IP Right Cessation
- 1987-12-30 CA CA000555579A patent/CA1290354C/en not_active Expired - Lifetime
- 1987-12-30 BE BE8701501A patent/BE1000871A4/en not_active IP Right Cessation
- 1987-12-30 IT IT23273/87A patent/IT1223624B/en active
Patent Citations (11)
Publication number | Priority date | Publication date | Assignee | Title |
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GB1063378A (en) * | 1963-07-10 | 1967-03-30 | Huels Chemische Werke Ag | Process for the removal of methylacetylene and propadiene from hydrocarbon mixtures |
GB1122018A (en) * | 1964-11-14 | 1968-07-31 | Huels Chemische Werke Ag | Removing butadiene and/or acetylenes from hydrocarbon mixtures |
GB1126848A (en) * | 1966-06-15 | 1968-09-11 | Bayer Ag | Process for the treatment by hydrogenation of c-hydrocarbons containing butadiene and n-but-1-ene |
GB1424288A (en) * | 1973-01-02 | 1976-02-11 | Monsanto Co | Elective hydrogenation process |
US3898298A (en) * | 1973-04-13 | 1975-08-05 | Atlantic Richfield Co | Selective hydrogenation of vinyl acetylene |
US3859377A (en) * | 1973-12-13 | 1975-01-07 | Monsanto Co | Selective hydrogenation of c' 4 'acetylenic hydrocarbons |
GB2018817B (en) * | 1978-04-05 | 1982-07-07 | Inst Francais Du Petrole | Selective hydrogenation of hydrocarbons |
US4247725A (en) * | 1978-04-21 | 1981-01-27 | Nippon Oil Company, Ltd. | Method of removing acetylenes from C4 -hydrocarbon mixture containing butadiene |
GB2053959B (en) * | 1979-07-06 | 1983-04-20 | Inst Francais Du Petrole | Purification of aromatic hydrocarbon cuts |
EP0081041A1 (en) * | 1981-11-04 | 1983-06-15 | Hüls Aktiengesellschaft | Process for the selective hydrogenation of polyunsaturated hydrocarbons in mixtures of hydrocarbons |
EP0087980A1 (en) * | 1982-03-02 | 1983-09-07 | Sumitomo Chemical Company, Limited | Method of selective hydrogenation of hydrocarbons |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
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US6509292B1 (en) | 2001-03-30 | 2003-01-21 | Sud-Chemie Inc. | Process for selective hydrogenation of acetylene in an ethylene purification process |
Also Published As
Publication number | Publication date |
---|---|
GB2199588B (en) | 1990-12-05 |
FI87453C (en) | 1993-01-11 |
IT8723273A0 (en) | 1987-12-30 |
FI875774A (en) | 1988-07-01 |
JP2560056B2 (en) | 1996-12-04 |
BE1000871A4 (en) | 1989-04-25 |
NL8703157A (en) | 1988-07-18 |
GB8631017D0 (en) | 1987-02-04 |
FI875774A0 (en) | 1987-12-30 |
IT1223624B (en) | 1990-09-29 |
FR2609023A1 (en) | 1988-07-01 |
FR2609023B1 (en) | 1989-10-20 |
DE3744086C2 (en) | 2000-05-04 |
FI87453B (en) | 1992-09-30 |
DE3744086A1 (en) | 1988-07-14 |
CA1290354C (en) | 1991-10-08 |
JPS63185935A (en) | 1988-08-01 |
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PCNP | Patent ceased through non-payment of renewal fee |
Effective date: 20051230 |