CN1195725C - Selective hydrogenation for preparing hexabydrobenzoic acid from benzoic acid - Google Patents
Selective hydrogenation for preparing hexabydrobenzoic acid from benzoic acid Download PDFInfo
- Publication number
- CN1195725C CN1195725C CNB011309768A CN01130976A CN1195725C CN 1195725 C CN1195725 C CN 1195725C CN B011309768 A CNB011309768 A CN B011309768A CN 01130976 A CN01130976 A CN 01130976A CN 1195725 C CN1195725 C CN 1195725C
- Authority
- CN
- China
- Prior art keywords
- acid
- gram
- hydrogen
- hydrogenation
- catalyzer
- 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.)
- Expired - Fee Related
Links
Abstract
The present invention relates to a method for preparing hexahydrobenzoic acid from benzoic acid through selective hydrogenation, which comprises the steps: hydrogen gas and liquid benzoic acid are in contact with a hydrogenation catalyst filled in a fixed bed reactor; the trickle bed reaction is carried out under the conditions that the temperature is from 160 to 220 DEG C, the hydrogen pressure is from 0.5 to 4.0MPa, the air speed is from 0.1 to 15.0 hr<-1> and the molar ratio of hydrogen gas to the benzoic acid is 3 to 15. The catalyst used by the method is weakly acidic aluminium oxide carrying a hydrogenation active component selected from platinum so as to have high catalytic activity and selectivity. The present invention is suitable for the technological process for preparing caprolactam by toluene as raw material.
Description
Technical field
The present invention is a kind of method of phenylformic acid selective hydrogenation to prepare hexahydrobenzene formic acid, specifically, is that phenylformic acid is contacted with hydrogen, the method for system hexahydrobenzene formic acid in the presence of selective hydrogenation catalyst.
Background technology
Existing industrial production hexanolactam is raw material with benzene mainly, and it is the technology of raw material production hexanolactam that the toluene of employing is also arranged.The latter has certain advantage for the more relatively factory of methylbenzene raw material.It is to be an intermediate reaction process of raw material production hexanolactam with toluene that hexahydrobenzene formic acid is produced in the phenylformic acid selective hydrogenation.Benzene hydrogenation is non-selective hydrogenation, document Hydrocarbon Processing, and 58 (11), 149-150, (1979) report that its catalyzer is Ni catalyzer or Pt/ aluminium oxide catalyst, adopts shell and tube or fixed-bed reactor more.With benzene hydrogenation relatively, benzoic acid hydrogenation is produced hexahydrobenzene formic acid and is belonged to selective hydrogenation, selectivity of catalyst is required comparatively strict, otherwise hydrogenation reaction occurs on the carboxyl and will generate corresponding aldehyde or alcohol.The catalysis journal, 18 (5), 384-387, (1997) and petrochemical complex, 28 (7), 429-431 and US5059716, US4585900, the catalyzer that US4613700 report benzoic acid hydrogenation prepares phenyl aldehyde has titanium, ytterbium, Mn/AL
2O
3And Mn-Cu-Zn/AL
2O
3Deng.
Selective hydrogenation prepares the catalyzer of hexahydrobenzene formic acid for benzoic acid hydrogenation, industrial use be palladium/carbon catalyst, hydrogenation reaction is carried out in tank reactor under 1.2～1.4MPa condition at 160～170 ℃.Because palladium/carbon catalyst is powder catalyst, with reaction raw materials and product difficulty separate.For reclaiming precious metal palladium, need palladium/carbon catalyst is thoroughly separated with other material of reaction system, therefore require the reactant phenylformic acid to transform fully, to reduce the subsequent processes step.Must adopt the series connection of four stills to react, not only complex process, and product hexahydrobenzene formic acid and catalyzer Long contact time also make secondary reaction increase for this reason, and reaction preference descends.Palladium/carbon catalyst loss in filtering separation, regeneration simultaneously is also bigger, causes the loss of precious metal palladium to increase.
Reactive Polymers, 18 (1992), the 1-6 report adopts the supported method of organo-metallic to prepare Pt-organic carrier catalyzer, just can carry out the benzoic acid hydrogenation reaction in room temperature and produce hexahydrobenzene formic acid, and transformation efficiency exists separation, recovery and regeneration problem near 100% equally but this catalyzer is used for industrial production.
SU1,270,939 disclose a kind of be used for that benzoic acid hydrogenation produces hexahydrobenzene formic acid carry the catalyzer of Pd by the porous hydrocarbon polymer, the carrier size is 50～500 nanometers, specific surface is 75～640 meters
2/ gram, average diameter of bore is 0.34～0.36 nanometer; Benzoic acid hydrogenation is reflected in the tank reactor and carries out.This catalyzer also is applicable to the hydrogenation of aromatic compound.
DE1,271,709 disclose a kind of method of producing hexahydrobenzene formic acid by benzoic acid hydrogenation, and this method requires preferably to use steam-laden hydrogen, but the contained water of phenylformic acid can not surpass 3 heavy %, preferably be no more than 1 heavy %, the Pd/C catalyst P d content that it adopts is about 5.0 heavy %, preferably 0.25～5.0 weighs %, and temperature of reaction is 160～250 ℃, pressure 0.1～4.0MPa, the phenylformic acid transformation efficiency of this method is higher.
In a word up to the present, it is all less that para Toluic Acid's selective hydrogenation prepares the research of the technology of hexahydrobenzene formic acid and catalyzer, especially adopts fixed-bed reactor to carry out the method that benzoic acid hydrogenation prepares hexahydrobenzene formic acid and do not see the pertinent literature report.
Summary of the invention
The purpose of this invention is to provide a kind of fixed-bed reactor that adopt and carry out the method that benzoic acid hydrogenation is produced hexahydrobenzene formic acid.
At benzoic acid hydrogenation catalyzer in the prior art is the problem of Powdered existence, and it is carrier that the present invention has selected a kind of weakly acidic aluminum oxide for use, and load has the metal active constituent of hydrogenating function, makes bar shaped catalyst.This catalyzer can be used for fixed-bed reactor, makes process simplification.Catalyzer has high reactivity, highly selective, is easy to the regenerated advantage, and particularly during carried noble metal, the precious metal in the decaying catalyst is easy to reclaim, and loses little.
Description of drawings
Fig. 1 carries out the schematic flow sheet that hexahydrobenzene formic acid is produced in the phenylformic acid selective hydrogenation for the present invention uses fixed bed.
Embodiment
The method of hexahydrobenzene formic acid is produced in phenylformic acid selective hydrogenation provided by the invention, comprising hydrogen is contacted with the hydrogenation catalyst that places fixed-bed reactor with liquid benzene formic acid, is 0.5～4.0MPa, air speed 0.1～15.0 hour at 160～220 ℃, hydrogen pressure
-1, hydrogen/phenylformic acid mol ratio 3～15 condition under carry out trickle bed reaction.
Temperature of reaction is preferred 170～210 ℃ in the aforesaid method, the preferred 0.8～2.0MPa of hydrogen pressure, preferred 0.5～5.0 o'clock of air speed
-1, hydrogen/phenylformic acid mol ratio preferred 5～8.
Selective hydrogenation catalyst provided by the invention is made up of the aluminum oxide of supported V IB or VIII family metal, and wherein the content of metal is 0.1～3.0 heavy %, and the specific surface area of alumina catalyst support is 160～210 meters
2/ gram, pore volume are that 0.5～0.6 milliliter/gram, surface acid center number are 0.2～1.5 * 10
20Individual/gram.
VIII family metal in the catalyzer is selected from platinum, palladium, nickel or cobalt, preferred platinum.The group vib metal is a molybdenum.
The comparatively preferred catalyzer of the present invention is made up of the aluminum oxide that carries platinum, platinum content preferred 0.5～2.0 heavy %, preferred 170～200 meters of the specific surface of alumina catalyst support
2/ gram, preferred 0.5～0.6 milliliter/gram of pore volume, surface acid center number preferred 0.7～1.3 * 10
20Individual/gram, its median pore diameter be the hole of 6.0～12.0 nanometers greater than 80%, be preferably greater than 90%.
Described slightly acidic alumina supporter is to be 230～250 meters by specific surface area
2/ gram, the alumina hydrate powder of average pore diameter 5～7 nanometers are through extruded moulding, and dry back makes in 500～1000 ℃ of roastings, and preferred maturing temperature is 600～950 ℃.This alumina supporter has the γ crystalline phase, or the crystalline phase of mixing of γ and η, and especially when high-temperature roasting, the gained carrier contains η-Al
2O
3, therefore, the surface-area of carrier is less, and pore volume is bigger.
Described carrier extrusion moulding can be used ordinary method, and alumina hydrate powder and extrusion aid are mixed, and adds a certain amount of peptizing agent again, and described extrusion aid is the sesbania powder, and its dosage is 0.1～2.0% of an alumina hydrate powder weight, and preferred 0.5～1.0%.Peptizing agent can be rare nitric acid, dilute hydrochloric acid, and its concentration is 2.0～10.0 heavy %.
Catalyzer of the present invention is with described metal compound solution impregnated alumina preparing carriers, preferred metallic compound is a Platinic chloride, make steeping fluid after Platinic chloride need being diluted with deionized water during preparation, liquid during dipping/solid volume ratio is 1.2～1.5: 1, dipping time is 4～24 hours, preferred 8～20 hours, should to make the metal content of catalyzer be 0.1～3.0 heavy % to the content of metallic compound in the steeping fluid.The dipping after-filtration, 60～120 ℃ of dryings 4～8 hours, roasting in 200～550 ℃ of air then.Air flow quantity is every gram catalyzer 50～100 ml/min during roasting, and the time is 2～24 hours.
The comparatively preferred roasting method of catalyzer of the present invention is with the carrier behind the impregnation drying, carries out roasting in air under three different temperature.Promptly 200～220 ℃, 350～380 ℃, 500～550 ℃ difference roasting 1～8 hour.Preferred 2～4 hours of first section roasting time, preferred 2～4 hours of second section roasting time, preferred 4～8 hours of the 3rd section roasting time.
Catalyzer of the present invention before use, need 350～550 ℃ with hydrogen reducing 2～4 hours, the volume ratio of hydrogen and catalyzer is 100～150: 1 during reduction, the flow of hydrogen is 100～550 milliliters/hour of every gram catalyzer during reduction.
The present invention is the trickle bed reaction with the process that fixed bed carries out the benzoic acid hydrogenation reaction, as shown in Figure 1, hydrogen and liquid phase benzene formic acid (temperature is greater than 140 ℃) by different pipelines by the mixed of hydrogen/phenylformic acid mol ratio 3～15: 1 after preheater 1 is preheating to required temperature of reaction, be ejected into the beds 6 of fixed-bed reactor 3 again through divider 2, phenylformic acid contacts with beds 6 with the droplet form.Reaction product enters rectifying tower 4 by pipeline 5 separates, and hexahydrobenzene formic acid product is discharged by the cat head of rectifying tower 4, and unreacted phenylformic acid is discharged by rectifying tower 4 bottoms and is recycled to further reaction in the reactor 3.The operational condition of rectifying tower is 230～234 ℃ of tower top temperatures, 240～250 ℃ of column bottom temperatures, and stage number is 50～70.
Further describe the present invention below by example.
Example 1
The catalyzer that preparation the present invention uses
(1) preparation carrier: get the alumina hydrate powder that the 100 gram trades mark are CI (Germany, Condea company produces), its physico-chemical property sees Table 1.Adding 1.0 gram sesbania powder in above-mentioned alumina hydrate powder is mixed, add concentration again and be 50 milliliters in rare nitric acid of 3 volume %, stir to mix and pinch, be extruded into external diameter then and be 1 millimeter bar, 120 ℃ of dryings 2 hours are cut into length and are 2～3 millimeters little, 850 ℃ of roastings 4 hours, obtain carrier a, its physico-chemical property sees Table 2.Specific surface in the described physico-chemical property, pore volume adopt cryogenic nitrogen absorption BET method to measure, and the acid site number is by NH
3-TDP method is measured (referring to volumes " zeolite catalysis and isolation technique " such as height taste, P19, Sinopec press).
(2) preparation catalyzer: get 8.5 milliliters of Platinic chlorides (platinum content is 2.8 mg/ml), add deionized water again and be made into 50 ml water solution.20 gram carrier a are added above-mentioned solution, flooded 12 hours, 120 ℃ of dryings were carried out roasting after 2 hours in the air, and gas flow is every gram catalyzer 100 ml/min.The nitrogen replacement air is used in 2 hours, 500 ℃ roastings of 2 hours, 380 ℃ roastings of 200 ℃ of roastings 4 hours then, uses hydrogen in 500 ℃ of reduction 4 hours again, and hydrogen flowing quantity is every gram catalyzer 5.0 ml/min, obtains catalyst A, and its character sees Table 3.
Comparative Examples 1
Method by example 1 prepares catalyst B, and different is that the used aluminum oxide powder trade mark is SB, and the Fushun catalyst plant is produced, and its character sees Table 1, and carrier and catalyst property see Table 2 respectively, table 3.
Comparative Examples 2
Method by example 1 prepares catalyzer C, different is HB that used aluminum oxide powder produces for the Fushun catalyst plant, and its character sees Table 1, and carrier and catalyst property see Table 2 respectively, table 3.
Comparative Examples 3
Method by example 1 prepares catalyzer D, different is SD-97 powder that used aluminum oxide powder produces for the Zhou village catalyst plant, and its character sees Table 1, and carrier and catalyst property see Table 2 respectively, table 3.
Example 2～5
This example is the phenylformic acid selective hydrogenation activity experiment of catalyzer.
In 20 milliliters of fixed-bed reactors, respectively A, B, C, D catalyzer are carried out the hydrogenation reaction activity rating.Get 10 gram catalyzer and pack in the reaction tubes, bed temperature is risen to 180 ℃, logical hydrogen, hydrogen and benzoic mol ratio are 5: 1, and reaction pressure is 1.0MPa, and air speed is 2 hours
-1, adopt fixed-bed reactor shown in Figure 1 to carry out the trickle bed reaction, reaction result sees Table 4.
Example 6
Catalyst A is placed 20 milliliters of fixed-bed reactors, under the differential responses condition, carry out evaluation test, the results are shown in Table 5.
Table 1
| Instance number | Example 1 | Comparative Examples 1 | Comparative Examples 2 | Comparative Examples 3 | |
| The alumina hydrate powder trade mark | CI | SB | HB | SD-97 | |
| Al 2O 3Content, heavy % | 73 | 73.3 | 80.1 | 73.9 | |
| Pore volume, milliliter/gram | 0.50 | 0.92 | 0.58 | 0.29 | |
| Specific surface, rice 2/ gram | 230 | 352 | 156 | 275 | |
| Average pore diameter, nm | 5.8 | 10 | 13.9 | 4.0 | |
| Pore distribution, % | ＜4.4nm | 5.8 | 0.4 | 1.9 | 53.8 |
| 4.4～10.6nm | 89.8 | 42.82 | 12.8 | 35.2 | |
| ＞10.6nm | 4.7 | 56.8 | 85.2 | 11.0 | |
Table 2
| Instance number | Bearer number | Specific surface, rice 2/ gram | Pore volume, milliliter/gram | The acid site number, 10 20Individual/gram | Pore distribution, % | ||
| ＜6.0nm | 6.0～12.0nm | ＞12.0nm | |||||
| 1 | a | 170 | 0.52 | 1.0 | 0.7 | 87.0 | 12.3 |
| Comparative Examples 1 | b | 225 | 0.42 | 1.2 | 5.8 | 52.7 | 41.5 |
| Comparative Examples 2 | c | 112 | 0.63 | 0.6 | 2.8 | 23.4 | 73.8 |
| Comparative Examples 3 | d | 200 | 0.34 | 0.9 | 45.9 | 45.6 | 8.5 |
Table 3
| Instance number | Example 1 | Comparative Examples 1 | Comparative Examples 2 | Comparative Examples 3 |
| The catalyzer numbering | A | B | C | D |
| Bearer number | a | b | c | d |
| Pt content, heavy % | 1.2 | 1.2 | 1.2 | 1.2 |
| Specific surface, rice 2/ gram | 170 | 225 | 112 | 200 |
| Pore volume, milliliter/gram | 0.52 | 0.42 | 0.63 | 0.34 |
| The acid site number, 10 20Individual/g | 1.0 | 2.0 | 0.6 | 0.9 |
Table 4
| Instance number | The catalyzer numbering | The phenylformic acid transformation efficiency, heavy % | Hexahydrobenzene formic acid selectivity, heavy % | Liquid is received, heavy % | Hexahydrobenzene formic acid yield, heavy % |
| 2 | A | 82.3 | 95.1 | 98.2 | 76.9 |
| 3 | B | 87.2 | 84.6 | 90.5 | 66.8 |
| 4 | C | 65.2 | 93.2 | 97.6 | 59.3 |
| 5 | D | 76.0 | 86.2 | 98.5 | 64.5 |
Table 5
| Reaction conditions | Reaction result, heavy % | ||||||
| Temperature, ℃ | Pressure, MPa | Air speed, the time -1 | Hydrogen/phenylformic acid, mole | Transformation efficiency | Liquid is received | Hexahydrobenzene formic acid yield | Hexahydrobenzene formic acid selectivity |
| 170 | 1.0 | 2 | 5 | 78.4 | 99.1 | 74.0 | 95.3 |
| 190 | 1.0 | 2 | 5 | 85.4 | 98.3 | 76.1 | 90.7 |
| 210 | 1.0 | 2 | 5 | 90.7 | 95.3 | 74.9 | 86.7 |
| 170 | 2.0 | 2 | 5 | 86.5 | 98.1 | 74.8 | 88.2 |
| 170 | 3.0 | 2 | 5 | 90.5 | 97.2 | 72.5 | 82.4 |
| 180 | 1.4 | 0.5 | 3 | 89.3 | 95.2 | 72.5 | 85.3 |
| 200 | 1.0 | 10 | 10 | 75.2 | 98.8 | 73.0 | 98.3 |
Claims (6)
1, the method for hexahydrobenzene formic acid is produced in a kind of phenylformic acid selective hydrogenation, comprising hydrogen is contacted with the bar shaped hydrogenation catalyst that places fixed-bed reactor with liquid benzene formic acid, is 0.5～4.0MPa, air speed 0.1～15.0 hour at 160～220 ℃, hydrogen pressure
-1, hydrogen/phenylformic acid mol ratio 3～15: 1 condition under carry out trickle bed reaction, described hydrogenation catalyst is made up of the aluminum oxide of load platinum, wherein the content of platinum is 0.1～3.0 weight %, the specific surface area of alumina supporter is 160～210 meters
2/ gram, pore volume are that 0.5～0.6 milliliter/gram, surface acid center number are 0.2～1.5 * 10
20Individual/gram.
2, in accordance with the method for claim 1, it is characterized in that described temperature of reaction is 170～210 ℃, the hydrogen dividing potential drop is 0.8～2.0MPa, and air speed is 0.5～5.0 hour
-1, hydrogen/phenylformic acid mol ratio is 5～8: 1.
3, in accordance with the method for claim 1, the specific surface that it is characterized in that described alumina supporter is 170～200 meters
2/ gram, pore volume are 0.5～0.6 milliliter/gram, and the surface acid center number is 0.7～1.3 * 10
20Individual/gram, bore dia is that the hole of 6.0～12.0 nanometers is greater than 80%.
4,, it is characterized in that described alumina supporter is is 230～250 meters by specific surface area according to claim 1 or 3 described methods
2/ gram, the alumina hydrate powder of average pore diameter 5～7 nanometers are through extruded moulding, and dry back makes in 500～1000 ℃ of roastings.
5, in accordance with the method for claim 1, it is characterized in that this catalyzer is that dry back is in 200～550 ℃ of roastings with platinum acid chloride solution oxide impregnation alumina supporter.
6, in accordance with the method for claim 5, it is characterized in that with platinum acid chloride solution oxide impregnation alumina supporter, dry back in 200～220 ℃, 350～380 ℃, 500～550 ℃ difference roasting 1～8 hour.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB011309768A CN1195725C (en) | 2001-08-29 | 2001-08-29 | Selective hydrogenation for preparing hexabydrobenzoic acid from benzoic acid |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB011309768A CN1195725C (en) | 2001-08-29 | 2001-08-29 | Selective hydrogenation for preparing hexabydrobenzoic acid from benzoic acid |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1406921A CN1406921A (en) | 2003-04-02 |
| CN1195725C true CN1195725C (en) | 2005-04-06 |
Family
ID=4670286
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB011309768A Expired - Fee Related CN1195725C (en) | 2001-08-29 | 2001-08-29 | Selective hydrogenation for preparing hexabydrobenzoic acid from benzoic acid |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN1195725C (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100352797C (en) * | 2005-10-17 | 2007-12-05 | 中国科学院长春应用化学研究所 | Novel process for synthesizing cyclohexyl formic acid by benzoic acid hydrogenation |
| CN102320958B (en) * | 2011-06-13 | 2013-11-13 | 华东理工大学 | Method and device for extracting hexahydrobenzoic acid from rearrangement reaction liquid |
| CN113058591B (en) * | 2021-03-25 | 2023-04-11 | 太原科技大学 | Preparation method and application of titanium oxide nanotube-confined platinum-based catalyst |
-
2001
- 2001-08-29 CN CNB011309768A patent/CN1195725C/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| CN1406921A (en) | 2003-04-02 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN1227214C (en) | Preparation for amine | |
| CN100512964C (en) | Film catalyst for tertiary amine production and method for producing tertiary amine using same | |
| CN107008477B (en) | Catalyst, preparation method thereof and method for preparing cyclohexylbenzene | |
| US6288295B1 (en) | Catalyst for use in organic compound transformation reactions | |
| CN101352690B (en) | Preparation method and use of molecular sieve catalyst for producing phenylethane from alkylation of benzene with dilute ethylene | |
| CN106660938B (en) | The method for producing the diamines and polyamines of diphenylmethane series | |
| CN104387340B (en) | A kind of method for preparing N methyl piperazines and its catalyst | |
| CN1195725C (en) | Selective hydrogenation for preparing hexabydrobenzoic acid from benzoic acid | |
| CN1049800A (en) | The preparation of nickel/aluminium oxide catalyst | |
| CN101817731A (en) | Method for preparing polymethoxy dimethyl ether by converting methanol | |
| CN1071308C (en) | Process for producing aromatic amines by gas phase hydrogenation and catalyst useful therefor | |
| CN1142016C (en) | Catalyst for preparation of hexahydrobenzoic acid by hydrogenation of benzoic acid | |
| CN101172237A (en) | Macropore capacity sulfureous-containing nickel catalyst for selective hydrogenation | |
| CN1769384A (en) | Heavy distillate oil hydrogenation catalyst and its preparation method | |
| CN105709786B (en) | A kind of selectively hydrogenating butadiene, 1 butylene heterogeneous catalyst and its preparation method and application | |
| CN102838439B (en) | Method for producing decahydronaphthalene through naphthalene hydrogenation | |
| CN1123389C (en) | Preparation of catalyst for preparing low-carbon alcohol by low-carbon oleffine hydration and its application | |
| CN101619235A (en) | Catalyst for hydro-upgrading of inferior diesel | |
| CN1286558C (en) | Catalyst filling material for selective hydrogenation | |
| CN1171853C (en) | Process for preparing phenylamine or alkylphenylamine | |
| CN1171854C (en) | Catalyst for preparing phenylamine or alkylphenylamine | |
| CN109721516B (en) | Thioether oxidation method | |
| CN102533313B (en) | Method for preparing ethylene and propylene through catalytic cracking | |
| CN101491760B (en) | Nickle base catalyst for producing butane-1 by hydro-isomerization of butane-2 | |
| WO2001097969A1 (en) | Process for the regeneration of zeolitic catalysts |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C17 | Cessation of patent right | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20050406 Termination date: 20110829 |