WO1996011744A1 - Verfahren zur aufarbeitung und verwertung von bortrifluorid-katalysatoren - Google Patents
Verfahren zur aufarbeitung und verwertung von bortrifluorid-katalysatoren Download PDFInfo
- Publication number
- WO1996011744A1 WO1996011744A1 PCT/DE1995/001435 DE9501435W WO9611744A1 WO 1996011744 A1 WO1996011744 A1 WO 1996011744A1 DE 9501435 W DE9501435 W DE 9501435W WO 9611744 A1 WO9611744 A1 WO 9611744A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- boric acid
- water
- boron trifluoride
- lime
- acid
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Ceased
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B7/00—Working up raw materials other than ores, e.g. scrap, to produce non-ferrous metals and compounds thereof; Methods of a general interest or applied to the winning of more than two metals
- C22B7/009—General processes for recovering metals or metallic compounds from spent catalysts
-
- 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
- B01J27/00—Catalysts comprising the elements or compounds of halogens, sulfur, selenium, tellurium, phosphorus or nitrogen; Catalysts comprising carbon compounds
- B01J27/28—Regeneration or reactivation
- B01J27/32—Regeneration or reactivation of catalysts comprising compounds of halogens
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B35/00—Boron; Compounds thereof
- C01B35/06—Boron halogen compounds
- C01B35/061—Halides
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B7/00—Halogens; Halogen acids
- C01B7/19—Fluorine; Hydrogen fluoride
- C01B7/191—Hydrogen fluoride
- C01B7/192—Preparation from fluorspar
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01F—COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM, CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THE RARE-EARTH METALS
- C01F11/00—Compounds of calcium, strontium, or barium
- C01F11/20—Halides
- C01F11/22—Fluorides
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- C03C1/00—Ingredients generally applicable to manufacture of glasses, glazes, or vitreous enamels
- C03C1/002—Use of waste materials, e.g. slags
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/20—Recycling
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
- Y02P20/50—Improvements relating to the production of bulk chemicals
- Y02P20/584—Recycling of catalysts
Definitions
- Boron trifluorine is used as a catalyst in numerous chemical reactions. Examples of such reactions are cationic polymerizations of olefins and olefin oxides, F ⁇ edel-Crafts alkylations and acylations, isomerizations and alkylations of paraffins
- the catalyst concentrations set vary widely depending on the task and can be between 10 ppm and 10 mol%, based on the components to be reacted in polymerizations and Isomerizations are inevitably controlled by the catalyst concentration in addition to the rate of conversion, the chain length distribution and thus the product properties 20
- boron trifluond is partly gaseous at a defined partial pressure. partly used as a solid or liquid adduct.
- Liquid adducts are, for example, those of ether, hydrofluoric acid and water; solid adducts use, for example, 2 * .
- the combination of a solid carrier and gaseous boron trifluoride secondary components, such as a defined proportion of water, can also have a significant effect on the reaction
- the highly corrosive tetrafluoroboric acid forms from boron trifluoron, which, like the boron trifluoron, must be separated from the reaction mixture after the reaction
- the gaseous catalyst is recovered by distillation or stipping of the boron fluoride from the reaction mixture and recycling of the gaseous catalyst into the reaction zone
- the decanted Bortnfluo ⁇ d phase can be recycled internally. For the washed-out residual quantities, recycling is not considered to be worthwhile.
- Plant internal recycling of the catalyst always means, in addition to the increased effort in the plant and the safety risk, also an increased quality risk, in particular in reactions in which a kinetically controlled product mixture is formed, such as in particular in polymerizations, oligomerizations and isomerizations.
- the exact regulation of the catalyst concentration as well as the cocatalysts and adduct formers required for direct recycling within the plant is extremely complex and difficult to control in terms of quality.
- Boron trifluoride is bound to potassium hydroxide solution or potassium fluoride to form stable potassium tetrafluoroborate.
- Potassium tetrafluorobarate is the preferred starting material for obtaining boron trifluoride from the point of view of energy and yield.
- the withdrawal of potassium tetrafluoroborate is therefore offered by manufacturers of boron trifluoride, since this residue can be integrated into existing boron trifluoride productions, provided that the potassium tetrafluoroborate is pure, i.e. is also delivered free of organic residues.
- US 4981578 (Ethyl Corp. 1991) describes a general process for removing boron trifluoride catalysts from reaction products.
- Solid alkali fluorides or, alternatively, an aqueous potassium fluoride solution are used as washing-out chemicals called.
- the dried and pure potassium tetrafluoroborate can be thermally split back into boron trifluoride and potassium fluoride.
- This is an example of a recycling which is preferably carried out centrally and outside the plant and which helps to reduce the high outlay for recycling within the plant.
- the relatively high price of potassium fluoride is disadvantageous.
- An alternative process is based on aqueous potassium hydroxide solution with the disadvantage that water is introduced into the reaction product.
- the object of the invention was therefore to develop a safe, economical and, as far as possible, universally applicable process for separating the catalysts from the reaction medium with a usability of the catalyst residues, which supplements and improves the known recycling processes.
- the background to this task was also the consideration of offering an economical central recycling solution for users of boron trifluoride who do not carry out internal recycling, which can replace previous disposal of the catalyst residues in landfills or waste water streams and meet the requirements of a circular economy becomes.
- the developed process is based on the idea that lime, by far the cheapest Lewis base, is an alternative to the adsorbents and absorbents for boron trifluoride and its accompanying substances described in the patent literature, such as hydrofluoric acid, if it succeeds, an alternative use for to open up the neutration products.
- lime in the form of calcium oxide, calcium hydroxide or chalk in boron trifluoride recycling has so far explicitly not played a role in the patent literature, since calcium tetrafluoroborate or the mixture of the hydrolysis products calcium fluoride and boric acid are possible but not customary starting materials for the Are boron trifluoride synthesis
- the use of lime or calcium compounds for the binding and neutralization of boron trifluoride becomes surprisingly attractive if, in addition to the two alternatives for catalyst residue, landfill and boron trifluide recovery described so far, an alternative use of the reaction products can be developed.
- the primary adducts are as reaction products Calcium tetrafluoroborate and their hydrolysis products calcium fluoride and boric acid were understood.
- a further object of the invention was to process the mixture of calcium fluoride and boric acid resulting from the hydrolysis and to break it down into the two components in such a way that a decoupled and safe use of these two versatile raw materials is possible
- the preferred form of presentation of lime in the context of the invention is hydrated lime powder. Due to the manufacturing process, this material has a large surface area and, in contrast to ground quicklime, is quickly and completely available for reaction with boron trifluoride and hydrofluoric acid. can be accepted, the use of an aqueous potassium hydroxide suspension is alternatively possible. Approximately only stoichiometric amounts are required according to the gross reaction equation
- the converted solid After thorough mixing of the introduced solid with the liquid reaction mixture consisting of catalyst and organic products, the converted solid is separated off by decanting, filtration or centrifugation. In particular in the case of adhering polymers, high boilers or odorless or toxicologically disruptive products, this is initially washed sludge-like residues with a good detergent are useful.
- the slightly alkaline filter cake is then mixed with water and - in a favorable variant of the process - additionally with calcium chloride, calcium chloride has an accelerating effect on the hydrolysis of the fluoroborate Boric acid
- This hydrolysis can be additionally required thermally and preferably takes place simultaneously with the removal by distillation of the adhering organic products or the organic detergents
- the desired complete separation of the evaporable organic constituents from the filter cake by distillation is possible in special kneading or thin-layer evaporators. Particularly preferred for drying this sludge are intensively mixing and indirectly heated kneading evaporators. Drying in vacuum mode is preferred. Solids temperatures higher than 165 ° C. are preferably avoided in order to avoid the conversion of orthoboric acid into poorly soluble metaboric acid.
- Drying results in a very fine powder mixture of approx. 60-65% calcium fluoride and 30 -35% boric acid if neutralized with a minimal excess of lime. If an excess of lime is used, some of the boric acid is bound as calcium borate.
- This product results from the properties of calcium fluoride as a flux e.g. in cement production and the property of boric acid and borates to influence the setting speed of the cement. Mixtures of calcium fluoride, calcium borate and boric acid can therefore in principle be used in cement production. It is particularly common in cement production to add calcium fluoride as a flux, which enables energy to be saved by reducing the firing temperature.
- the fine grain in which this intermediate product is obtained is, however, also particularly favorable for the further processing of the mixture by extraction of the boron compounds.
- a stoichiometric amount of sulfuric acid is preferably added before the extraction in order to release boric acid from the calcium borate.
- Preferred solvents for boric acid extraction are hot (70-120 ° C.) water or combinations of hot water and up to 0.2 parts by weight of sodium hydroxide solution, based on the proportion of boric acid, or in particular also water-soluble aliphatic amines and alkanolamines.
- the subsequent separation of the extract from insoluble calcium fluoride is carried out by filtration or preferably by centrifugation.
- the use of hot water has the advantage that, after the aqueous phase has cooled, a technical boric acid crystallizes out, so that a separation into crystalline boric acid and an aqueous phase which can be used for further extractions is easily possible.
- the background is the pronounced temperature dependence of the solubility of boric acid in water, which is 23% by weight at 90 ° C and only 4.6% by weight at 20 ° C.
- Such concentrates of boric acid or its sodium salts have a widespread use as a fungicide and as a fire protection agent. This gives the opportunity to allow the extract from the removal of the boric acid to flow directly into such formulations without further workup steps.
- the calcium fluoride residue remaining during the extraction is preferably washed with water.
- the boric acid-containing wash water can be used together with the extract directly as an aqueous fungicide, for example in the area of particle board, or after cooling and partial crystallization of the boric acid in a cycle mode can be used for further boric acid extractions.
- the residue, which is largely freed from boric acid consists almost exclusively of calcium fluoride, which is used as a flux and as a raw material source for hydrofluoric acid and other fluorochemicals.
- the fine-grained form is generally of great advantage for use as a flux. There is no need for complex milling processes.
- This calcium fluoride compared to naturally occurring technical qualities is important for use as a raw material for fluorine chemistry, in particular the production of hydrogen fluoride.
- accompanying substances such as quartz interfere considerably, since in this case, in addition to hydrogen fluoride, the silicon tetrafluoride, which would then be difficult to separate, would also arise.
- extremely pure lime qualities for the implementation of the catalysts it is possible to obtain extremely pure and fine calcium fluoride particles. This also shows a way of producing fine, amorphous calcium fluoride which can offer advantages in special applications, for example in the production of special glasses such as frosted glass or optical lenses.
- the discontinuous production of a hydrocarbon resin by cationic polymerization with the addition of boron trifluoride is terminated by adding powdered lime (hydrated lime) in the well-stirred stirred tank. 2 parts by weight of calcium hydroxide were added to 1 part by weight of boron trifluoride. After switching off the stirrer, the solid phase formed was filtered off and washed with an aromatic solvent mixture in the boiling range 160-210 ° C. The filter cake was then dried in a 160 l turbulent dryer (Drais) by indirect heating at an absolute pressure of 60 mbar. The speed of rotation of the kneading arms of the tumble dryer was 90 rpm.
- powdered lime hydrated lime
- Example 1 The powder obtained in Example 1 was admixed with 3 parts of water and 0.03 part of sodium hydroxide solution at 90 ° C. and stirred in the turbulent mixer described in Example 1 for 4 hours. After the kneading elements had been switched off, the calcium fluoride settled rapidly -containing solution separated The analysis of the solution showed that 69% of the amount of boron had gone into solution
- Example 1 The powder obtained in Example 1 was adjusted to pH 50 with dilute sulfuric acid, mixed with 1 part of monoethanolamine and 0.1 part of calcium chloride and stirred at 40 ° C. for 5 hours. Analysis of the extract solution showed that 91.5% of the existing Amount of boron had gone into solution
- EXAMPLE 4 s
- the powder obtained in Example 1 was adjusted to pH 5 with aqueous sulfuric acid and 1 part of powder 6 parts of water were slurried with water in a weight ratio of 80 and the mixture was stirred for 4 hours. After filtration and rinsing with 2 parts by weight of water, based on the solids obtained, 82% of the total amount of boron was contained 0
- Example 1 The powder obtained in Example 1 was melted at 1330 ° C. in an oxidizing flame. The melt solidified on cooling to form a light slag with a closed ceramic surface. The weight ratio of boron and fluorine s remained unchanged. The subsequent reaction of this solidified melt with oleum at 120 ° C gave gaseous boron trifluond. The decomposition and decomposition of the solids proceeded quickly and completely
- Example 6 The powder obtained in Example 1 with still small amounts of high-boiling organic residues was subjected to pyrolysis at 450 ° C. for 2 hours. The organic residues then had no noticeable odor. The petroleum ether extract of the residue gave 1200 ppm extractable organic Fabrics
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Inorganic Chemistry (AREA)
- Materials Engineering (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Life Sciences & Earth Sciences (AREA)
- Geology (AREA)
- Geochemistry & Mineralogy (AREA)
- Environmental & Geological Engineering (AREA)
- General Life Sciences & Earth Sciences (AREA)
- General Chemical & Material Sciences (AREA)
- Manufacturing & Machinery (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Catalysts (AREA)
Abstract
Description
Claims
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| EP95934057A EP0787039A1 (de) | 1994-10-18 | 1995-10-12 | Verfahren zur aufarbeitung und verwertung von bortrifluorid-katalysatoren |
| AU36499/95A AU3649995A (en) | 1994-10-18 | 1995-10-12 | Process for reprocessing and utilizing boron trifluoride catalyst residues |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19944437138 DE4437138C1 (de) | 1994-10-18 | 1994-10-18 | Verfahren zur Aufarbeitung und Verwertung von Bortrifluorid-Katalysatorrückständen |
| DEP4437138.1 | 1994-10-18 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| WO1996011744A1 true WO1996011744A1 (de) | 1996-04-25 |
Family
ID=6531017
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| PCT/DE1995/001435 Ceased WO1996011744A1 (de) | 1994-10-18 | 1995-10-12 | Verfahren zur aufarbeitung und verwertung von bortrifluorid-katalysatoren |
Country Status (4)
| Country | Link |
|---|---|
| EP (1) | EP0787039A1 (de) |
| AU (1) | AU3649995A (de) |
| DE (1) | DE4437138C1 (de) |
| WO (1) | WO1996011744A1 (de) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104923304A (zh) * | 2015-05-13 | 2015-09-23 | 安徽金邦医药化工有限公司 | 一种活性炭负载型复合固体酸催化剂及其制作方法 |
| CN104923302A (zh) * | 2015-05-13 | 2015-09-23 | 安徽金邦医药化工有限公司 | 一种强度高的复合固体酸催化剂及其制作方法 |
| CN104923267A (zh) * | 2015-05-13 | 2015-09-23 | 安徽金邦医药化工有限公司 | 一种选择性高复合固体酸催化剂及其制作方法 |
| CN104923311A (zh) * | 2015-05-13 | 2015-09-23 | 安徽金邦医药化工有限公司 | 一种高吸附性复合固体酸催化剂及其制作方法 |
| CN104923300A (zh) * | 2015-05-13 | 2015-09-23 | 安徽金邦医药化工有限公司 | 一种稻谷灰基复合固体酸催化剂及其制作方法 |
| CN104923280A (zh) * | 2015-05-13 | 2015-09-23 | 安徽金邦医药化工有限公司 | 一种硝酸根转化率高的复合固体酸催化剂及其制作方法 |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4238417A (en) * | 1979-08-15 | 1980-12-09 | Gulf Research & Development Company | Decomposition of cumene hydroperoxide and recovery of boron trifluoride catalyst |
| EP0364815A2 (de) * | 1988-10-17 | 1990-04-25 | Ethyl Corporation | Rückgewinnung von BF3 aus einem Olefinoligomerisationsverfahren |
| EP0594065A1 (de) * | 1992-10-19 | 1994-04-27 | Idemitsu Petrochemical Co., Ltd. | Verfahren zur Wiedergewinnung von Bortrifluorid |
-
1994
- 1994-10-18 DE DE19944437138 patent/DE4437138C1/de not_active Expired - Fee Related
-
1995
- 1995-10-12 EP EP95934057A patent/EP0787039A1/de not_active Withdrawn
- 1995-10-12 WO PCT/DE1995/001435 patent/WO1996011744A1/de not_active Ceased
- 1995-10-12 AU AU36499/95A patent/AU3649995A/en not_active Abandoned
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4238417A (en) * | 1979-08-15 | 1980-12-09 | Gulf Research & Development Company | Decomposition of cumene hydroperoxide and recovery of boron trifluoride catalyst |
| EP0364815A2 (de) * | 1988-10-17 | 1990-04-25 | Ethyl Corporation | Rückgewinnung von BF3 aus einem Olefinoligomerisationsverfahren |
| EP0594065A1 (de) * | 1992-10-19 | 1994-04-27 | Idemitsu Petrochemical Co., Ltd. | Verfahren zur Wiedergewinnung von Bortrifluorid |
Also Published As
| Publication number | Publication date |
|---|---|
| AU3649995A (en) | 1996-05-06 |
| DE4437138C1 (de) | 1996-06-05 |
| EP0787039A1 (de) | 1997-08-06 |
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