CN1039805C - Method for prepn. of electronic grade ZrO2 by Zircon - Google Patents
Method for prepn. of electronic grade ZrO2 by Zircon Download PDFInfo
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- CN1039805C CN1039805C CN95104103A CN95104103A CN1039805C CN 1039805 C CN1039805 C CN 1039805C CN 95104103 A CN95104103 A CN 95104103A CN 95104103 A CN95104103 A CN 95104103A CN 1039805 C CN1039805 C CN 1039805C
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Abstract
The present invention relates to a preparation method of electronic grade zirconium dioxide, which comprises the following steps: zirconite alkali decomposition, water immersion of decomposition products for removing silica and sodium, silica removal by gel after acid transformation, concentration crystallization of a zirconium solution, recrystallization of zirconium oxychloride, and direct calcination of two sections. The method of the present invention has the advantages of low cost, low raw material consumption, and saving of large amounts of energy consumption, and can be used for preparing pure electronic grade zirconium dioxide.
Description
The present invention relates to the preparation method of the oxide compound of zirconium.
Along with the development of electronic industry, zirconium dioxide is remarkable day by day as the status of functional material in electronic industry.It is widely used in piezoelectric element (as piezoelectric buzzer, piezoelectric speaker, piezoelectric actuator etc.), sensing member (as sensing members such as gas, temperature, sound, pressure, acceleration), wave filter, ultrasonic oscillator, high-temperature electric heat element etc.Since the nineties, under solid electrolyte fuel cell practicability promotes, as its main function material zirconium dioxide year consumption just with 12～15% speed increment.
The production method of zirconium dioxide mainly contains chlorination process and alkali fusion at present.
Chlorination process is that zircon concentrate is got zirconium dioxide through high-temp chlorination, fractional condensation, rectifying, metathesis, neutralization precipitation and calcining.This method product can satisfy the nuclear industry requirement, but exists zirconium ore specification of quality height, equipment complexity and life-span are short, energy consumption is high, seriously polluted, investment is big, cost is high and some foreign matter content can not satisfy shortcomings such as electronic industry requirement.
Alkali fusion is that zircon concentrate is got through alkali fusion decomposition, water logging, sour molten extraction, neutralization precipitation and calcining.As disclosing this method in " rare metal " 1988 (3) and " external rare metal " 1989 (5), that this method has is tight to the starting material requirement, technology and equipment is simple, investment and less cost of power.But exist the industrial chemicals consumption big in producing at present, the low shortcomings such as (60～65%) of zirconium yield.Its concrete steps are as follows: the first step: zircon alkali decomposes
Zircon alkali decomposes sodium hydroxide fusion process and soda or lime sinter process, and wherein the sodium hydroxide fusion process is the ZrSiO that chemical stability is high
4Be converted into Na
2ZrO
3And Na
4SiO
4(or Na
2SiO
3), under certain condition, zircon and sodium hydroxide are done the time spent, and principal reaction is as follows:
Meanwhile, major impurity Ti and Fe will generate corresponding sodium salts Na in the ore deposit
2TiO
3And Na
2FeO
2Second step: degradation production water logging silica removal and sodium
Its objective is and remove most silicon and sodium, make zirconium and silicon and sodium initial gross separation.In the water logging process, Na
4SiO
4, Na
2SiO
3And Na
2FeO
2Deng being dissolved in water, then carry out solid-liquid separation and remove most of Si and Na.The 3rd step: acid transforms silica removal
The purpose that solid product acid transforms after the water logging is to make zirconium with ZrOCl
2Form changes solution over to, and remaining silicon is then removed with the silicic acid form.The process principal reaction is as follows:
Can find out that from formula (6～9) preceding operation is with Na
2ZrO
3With remaining Na
4SiO
4Hydrolysis is converted into ZrO (OH)
2And H
4SiO
4, this operation acid consumption is reduced at double, and reduce the content of NaCl in the zirconium liquid.
Since silicic acid exist factors such as form and acidity of medium closely related, under the traditional technology condition, silicon mainly exists with the silicon sol form in the sour conversion process, not only the continuous back of influence quality product, and influence the isolating filtration velocity of zirconium silicon, bring the loss of the deuce to pay and increase zirconium to production.The 4th step: the condensing crystal of zirconium liquid
The purpose of zirconyl chloride solution condensing crystal is that impurity F e, Ti, Na, Al etc. in the zirconium solution are separated with zirconium.The characteristic that process raises and reduces with concentration of hydrochloric acid based on the solubleness of zirconium oxychloride, and its solubleness also depends on temperature consumingly, when the solubleness in the time of 70 ℃ is 20 ℃ 5 times.Therefore zirconium liquid can be concentrated, add HCl subsequently and realize with the reduction temperature.
In current technology, because of zirconium concentration in the original zirconium liquid is low, sodium and silicon concentration height (are respectively 15～18g/L and 0.8～1.0g/L), in order to obtain technical grade oxygen zirconium white, adopt low zirconium peracid crystallization process, control zirconium concentration 60～80g/L usually, HCl 6.0～6.5mol/L.The 5th step: the purification of zirconium oxychloride
The purpose that zirconium oxychloride purifies is further to remove impurity such as Fe, Ti, Si, Na, to obtain the high purity zirconium compound.At present both at home and abroad mainly adopt sour molten crystallization process behind organic solvent extraction and the neutralization precipitation, but have complex process, the chemical reagent consumption is big, the cost height, and wastewater flow rate is big and be difficult to shortcoming such as processing.The 6th step: the preparation of zirconium dioxide
Prepare high-purity ZrO by zirconium oxychloride
2, usually zirconium oxychloride being converted into hydronium(ion) oxidation zirconium and calcining and get, Principle of Process is as follows:
This method is mainly HCl when avoiding high temperature directly to calcine zirconium oxychloride to the corrosion of container and introduce impurity.But this method need increase equipment and consume a large amount of SILVER REAGENT ammoniacal liquor, and because of hydronium(ion) oxidation zirconium moisture up to 82～85%, so energy consumption height when calcining.
Still can not obtain to contain Zr (Hf) O at present by above method
2＞99.7% zirconium dioxide promptly be difficult to prepare the electronic grade ZrO 2 that high purity requires, and the zirconium yield only is 60～65%.
The objective of the invention is to produce the problem that zirconium dioxide exists, it is proposed the process modification scheme with acquisition high pure electronic grade ZrO 2, and improve the zirconium yield at alkali fusion.
The present invention is as follows to the improvement project of the method for alkali fusion production electronic grade ZrO 2:
1, carries out the gelling silica removal in the 3rd step acid of alkali fusion after transforming.
Silicon behavior in acidic medium can be represented by the formula:
Find out that from formula along with the raising of acidity, process is carried out towards the reaction of the connection of the hydroxyl between neutral molecule and protonated silicic acid positive ion, therefore can be represented by the formula in high acidity conversion process:
When zirconates cooled off, the silicic acid particle aggregated into tridimensional network and forms gel.Water-soluble when going out zirconium oxychloride when adding, silica gel is reunited and is convenient to clarification filtration and removes.The contriver finds through exploration and test, its gelation rate and zirconium silicon separating effect and acidity of medium, and silicon concentration, gelation time and temperature are relevant.When the initial acidity of medium is 4.0～8.0N, silicon concentration is 4.5～14.0g/L, leaves standstill under 5～36 ℃ 6～24 hours, adds water and makes zirconates dissolving after-filtration that zirconium is thoroughly separated with silicon.
Table 1 is the test-results of gelling silica removal of the present invention
Watch 1 order silica removal drops into material output zirconium solution and receives filtrations method Zr (g) Si (g) the total Zr of Zr g/L (g) the total Si of Si g/L (g) rate % except the Si zirconium and lead 1 acid of % performance and turn 95.88 4.64 115.2 94.44 0.056 0.046 99.01 98.5 fast 2 to change rear 95.88 4.64 89.71 93.77 0.042 0.040 99.74 97.8 fast 3 gellings, 1917.6 92.80 90.22 1894.6 0.049 1.029 98.89 98.8 fast 4 methods, 1917.6 92.80 97.15 1886.9 0.038 0.742 99.20 98.4 fast sour conversion methods 95.88 4.64 62.58 86.10 0.852 1.108 76.11 89.8 extremely slow
As seen from Table 1, silica removal method of the present invention compared with prior art, the silica removal rate improves more than 20%, it is about 9% that the zirconium rate of recovery improves, filtration velocity improves 8 times approximately, and obtains the low silicon solution of high zirconium, makes the subsequent handling condensing crystal save a large amount of energy and hydrochloric acid.
2, the 5th step was adopted the zirconium oxychloride recrystallization method
After being about to primary crystallization (the 4th step), product being water-soluble, regulate Zr concentration 80～169g/L, [H
+] 3～7N, 3～35 ℃ of following crystallizations.This method can obtain the high purity oxygen zirconium chloride, is electronic-grade ZrO
2Produce high quality raw material be provided.
Test used ZrOCl
2.8H
2The O composition is (%): ZrO
235.35, Fe
2O
30.0032, TiO
2Be 0.0044, SiO
20.0025, Na
2O 0.0028.
Table 2 is zirconium oxychloride recrystallization test-results
Table 2 preface input oxygen output high-purity zirconium oxychloride composition (%) output object contains ZrO zirconium knot zirconium and returns
The brilliant rate yield of zirconium chloride number contains zirconium amount ZrO
2Fe
2O
3TiO
2SiO
2Na
3O crystalline mother solution (%) (%)
(g) ZrO
2(g)ZrO
2(g)1 78.7 36.12 0.005 0.0007 0.0007 0.0012 65.27 5.15 92.32 99.682 353.5 36.29 0.002 0.0001 0.0008 0.0005 324.83 27.95 91.66 89.673 1868.5 36.13 0.001 0.0001 0.0006 0.0005 978.67 86.12 91.52 99.654 2121.8 36.15 0.001 0.0001 0.0005 0.0005 1957.4 157.24 92.93 99.70
As seen from Table 2, recrystallization method has significant decontamination effect improving, and the zirconium direct yield and the rate of recovery are also high.
3, the 6th step adopted two-phase method directly to calcine the preparation electronic grade ZrO 2.
The direct incinerating principal reaction of zirconium oxychloride is as follows:
There is not theoretical question in the direct calcination method of zirconium oxychloride, but has the problem of zirconium oxychloride degradation production HCl heavy corrosion container under the high temperature in the practice process.The contriver is to ZrOCl for this reason
28H
2The mechanism of O decomposition course under differing temps has been carried out some exploration, and experimental result shows, ZrOCl
28H
2O at first sloughs four crystal water in the time of 80～100 ℃, separate out there not being chlorine below 120 ℃ substantially, but 80～85%, 315 ℃ of dechlorinations of 215 ℃ of dechlorinations are complete substantially, generate unformed ZrO
2Hydrate.
Based on zirconium oxychloride decomposition course mechanism, HCl is to the corrosion of container under the high temperature in order to reduce, and the contriver tests, and test-results is as shown in table 3, and calcining temperature and time are closely related to the corrosion of quality product and container as a result.When calcination process divides two sections to carry out, the first section calcining temperature is controlled at 150～300 ℃, and 1～4 hour time, the second section calcining temperature is 600～900 ℃, and 0.5～2 hour time, product best in quality do not have corrosion substantially to container.Container material can be the general high alumina ceramic of prior art, conventional ceramic, heat-resistant hard glass, corundum etc.
Table 3 preface calcining temperature and time product ZrO foreign matter content % container material corrosion number ℃ Fe
2O
3TiO
2SiO
2Na
2The O situation
First section second section 1 300 (1h)--900 (2h), 0.0052 0.0003 0.0028 0.0032 high alumina ceramics do not have 2 150 (4h)--700 (2h), 0.0008 0.0002 0.0010 0.0029 conventional ceramics do not have 3 300 (1h)--600 (2h), 0.0003 0.0002 0.0007 0.0016 corundum do not have 4 350 (2h)--900 (0.5h) 0.0008 0.0001 0.0011 0.0014 heat-resisting hard
Glass does not have 5 200 (3h)--and 900 (2h), 0.0003 0.0002 0.0007 0.0023 corundum do not have
Annotate: ZrO
2Middle Ca, Mg, Al all find in detection, Zr (Hf) O
2＞99.9%.
Present domestic electronic-grade ZrO
2Standard is the no data report still, and quality product of the present invention and Taiwan and Siemens like product quality comparing result are listed in table 4.
Table 4
| Product composition % | |||||
| The place of production | Zr(Hf)O 2 | Fe 2O 3 | TiO 2 | SiO 2 | Na 2O |
| Taiwan of the present invention Germany | 99.9 99.8 99.8 | 0.001 0.001 0.002 | 0.002 0.004 0.02 | 0.002 0.04 0.02 | 0.002 -- 0.002 |
As seen from Table 4, products obtained therefrom quality of the present invention is higher than Taiwan and German product.
The present invention compared with prior art has following advantage:
1, raw materials consumption and cost are low, zircon, sodium hydroxide and hydrochloric acid consumption and existing technical grade ZrO
2Production technology is compared and is reduced by 20%, 30% and 35% respectively, and can produce high pure electronic grade ZrO
2
2, technological process is simple, and facility investment is few, and quality product is higher than Taiwan and German electronic-grade ZrO
2Product.
3, saved organic solvent and SILVER REAGENT ammoniacal liquor, and made the HCl of calcination process output obtain recycling, avoided of the pollution of a large amount of waste water of extraction and neutralisation generation environment.
4, adopt gelling silica removal, zirconium oxychloride recrystallization and two sections direct calcination methods of zirconium oxychloride, saved a large amount of energy consumptions.
Embodiment one:
1.5Kg zircon (ZrO
261.42%, SiO
230.12%, as follows) in reactor, react 1.5h down with the 1.9Kg caustic soda at 700～750 ℃, obtain loose reaction product 2.79Kg.Add water logging by liquid-solid ratio 4 and go out 30min, the solid product behind the filtration washing is 6N at 70～75 ℃ with initial acidity, SiO
214.0g/l condition under react 20min, after making silicic acid gelling 16h under 18～25 ℃ of conditions, add the water-soluble ZrOCl of going out subsequently
2, filter the solution 6.92L that the back obtains to contain Zr 96.3g/l, Si 0.045g/l, from the decomposition of zircon alkali, water logging and gelling silica removal, so far, the zirconium direct yield is 97.7%, silicon clearance 99.93%.
The gained zirconyl chloride solution concentrate and acid adjustment to containing Zr138.6g/l, [H
+] 4.3N, 18～23 ℃ of following crystallizations, after filtration the washing after, with ion exchanged water with ZrOCl
2.8HO stripping and acid adjustment are to containing Zr120g/l, [H
+] 5.3N, at 20～23 ℃ of following recrystallizations, obtain high-purity ZrOCl after filtering
2.8H
2O 2.092Kg.Recrystallized product contains (%): ZrO
236.5, Fe
2O
30.0002, TiO
20.0001, SiO
20.0008, Na
2O 0.0005.High-purity zirconium oxychloride is behind 150 ℃ of following roasting 4h, in 500 ℃ of calcining 2.0h, electron gain level ZrO
2753.2g product contains (%): Zr (Hf) O
299.92, Fe
2-O
30.0004, TiO
20.0002, SiO
20.0009, Na
2O 0.0019.Whole process zirconium direct yield 81.7%.
First and second crystalline mother solution is made pyroceramic pigment batching through reclaiming zirconium, and then the zirconium total yield is 92.1%.
Embodiment two:
Zircon 106Kg and caustic soda 136Kg react 2h down at 720～760 ℃ in reactor, obtain loose granular product 215Kg.Add water logging by liquid curing ratio 6 and go out 40min, the gained solid product is 8N.SiO at 60～70 ℃ with initial acidity behind the filtration washing
28.7g/l condition under react 30min, after making silicic acid gelling 24h under 26～36 ℃ of conditions, add the water-soluble ZrOCl of going out subsequently
2, filter the back and obtain to contain Zr 95.5g/l, SiO
20.039g/l solution 494.L, from feeding intake so far, the zirconium direct yield is 97.9%, silicon clearance 99.94%.
Zirconyl chloride solution concentrated and acid adjustment to containing Zr 142.3g/l, [H
+] 4.6K, 25～32 ℃ of following crystallizations, after filtration the washing after, dissolve ZrOCl with exchanged water
28HO, and acid adjustment is to containing Zr169g/l, [H
+] 3.0N, at 25～35 ℃ of following recrystallizations, obtain high-purity ZrOCl after filtering
28H
2O 148.9Kg.Recrystallized product ZrOCl
2.8H
2O contains (%): ZrO
235.7, Fe
2O
30.0001, TiO
20.0001, SiO
20.0006, Na
2O 0.0005.
The high-purity ZrOCl of gained
2.8H
2O is behind 250 ℃ of following roasting 2h, in 700 ℃ of calcining 1.5h, electron gain level ZrO
252.8Kg product contains (%): Zr (Hf) O
299.93, Fe
2O
30.0003, TiO
20.0002, SiO
20.0007, Na
2O 0.0016.Whole process zirconium direct yield 81.1%.
First and second crystalline mother solution is made pyroceramic pigment batching through reclaiming zirconium, and then the zirconium total yield is 91.8%.
Embodiment three:
Zircon 118Kg and caustic soda 160Kg react 2h down at 720～76O ℃ in reactor, obtain loose granular reaction product 249Kg.By liquid-solid, add water logging than 6 and go out 40min, the gained solid product is 4.5N, SiO at 65～70 ℃ with initial acidity behind the filtration washing
24.5g/l condition under react 40min, after making silicic acid gelling 6h under 5～10 ℃ of conditions, add the water-soluble ZrOCl of going out subsequently
2, filter the back and obtain to contain Zr 85.3g/l, SiO
20.029g/l solution 617.6L, from feeding intake so far, the zirconium direct yield is 98.2%, silicon clearance 99.99%.
Above-mentioned gained zirconium solution concentrated and acid adjustment to containing Zr 129.5g/l, [H
+] 4.2N, 7～12 ℃ of following crystallizations, ZrOCl is dissolved with exchanged water in washing back after filtration
28H
2O, and acid adjustment is to containing Zr 81.6g/l, [H
+] 7.0N, at 3～11 ℃ of following recrystallizations, obtain high-purity ZrOCl after filtering
2.8H
2O 167.9Kg.Recrystallized product ZrOCl
28HO contains (%): ZrO
235.9, Fe
2O
30.0001, TiO
20.0002, SiO
20.0005, Na
2O 0.0005.
Gained ZrOCl
2.8H
2O is behind 350 ℃ of following roasting 1h, in 900 ℃ of calcining 0.5h, electron gain level ZrO
260.29Kg product contains (%): Zr (Hf) O
299.91, Fe
2O
30.0008, TiO
20.0001, SiO
20.0001, Na
2O 0.0014.Whole process zirconium direct yield 83.2%.
First and second crystalline mother solution is made pyroceramic pigment batching through reclaiming zirconium, and then the zirconium total yield is 92.3%.
Claims (1)
1, a kind of method of producing electronic grade ZrO 2 from zircon, may further comprise the steps: the first step, zircon alkali decompose, second step, degradation production water logging silica removal and sodium, the 3rd step, acid transform silica removal, the condensing crystal of the 4th step, zirconium liquid, the purification of the 5th step, zirconium oxychloride, the preparation of the 6th step, zirconium dioxide, it is characterized in that carrying out gelling after the acid conversion of the 3rd step, in the initial acidity of medium is that 4.0～8.0N, silicon concentration are to leave standstill 6～24 hours under the 4.5～14.0g/L, 5～36 ℃, adds water and makes zirconates dissolving after-filtration; The 5th step was adopted the zirconium oxychloride recrystallization, with the 4th step product water-soluble after, regulate zirconium concentration 80～169g/L, [H
+] 3～7N, 3～35 ℃ of following crystallizations: the 6th step adopted two sections directly to calcine, and the first section calcining temperature is 150～350 ℃, calcination time 1～4 hour, 600～900 ℃ of the second section calcining temperature, calcination time 0.5～2 hour.
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|---|---|---|---|
| CN95104103A CN1039805C (en) | 1995-03-31 | 1995-03-31 | Method for prepn. of electronic grade ZrO2 by Zircon |
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|---|---|---|---|
| CN95104103A CN1039805C (en) | 1995-03-31 | 1995-03-31 | Method for prepn. of electronic grade ZrO2 by Zircon |
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|---|---|
| CN1132181A CN1132181A (en) | 1996-10-02 |
| CN1039805C true CN1039805C (en) | 1998-09-16 |
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| CN95104103A Expired - Fee Related CN1039805C (en) | 1995-03-31 | 1995-03-31 | Method for prepn. of electronic grade ZrO2 by Zircon |
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Families Citing this family (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100343174C (en) * | 2005-05-25 | 2007-10-17 | 宜兴新兴锆业有限公司 | High-purity ultra-fine zirconia production process |
| CN101746730B (en) * | 2009-12-16 | 2012-07-04 | 北京有色金属研究总院 | Process for decomposing zircon by alkali fusion |
| CN103253700A (en) * | 2012-02-15 | 2013-08-21 | 淄博市周村磊宝耐火材料有限公司 | Method for purification of zircon sand to prepare high purity zirconia |
| CN103253701A (en) * | 2012-02-15 | 2013-08-21 | 淄博市周村磊宝耐火材料有限公司 | Method for purification of baddeleyite to prepare high purity zirconia |
| CN102616843A (en) * | 2012-04-05 | 2012-08-01 | 北京瑞源化工技术有限公司 | Method for removing silica sol in process of recovering zirconium from raffinate of zirconium oxychloride crystallization mother solution |
| CN102602993A (en) * | 2012-04-05 | 2012-07-25 | 北京瑞源化工技术有限公司 | Method for recovering zirconium element from zirconium oxychloride crystallized mother liquor raffinate |
| CN103011278B (en) * | 2013-01-11 | 2014-11-26 | 周涛 | Process for hydrothermally preparing zirconium oxychloride with low alkali consumption |
| CN110980805A (en) * | 2019-12-19 | 2020-04-10 | 山东鸿远新材料科技有限公司 | Production process of high-purity zirconium oxychloride solution |
| CN113753950B (en) * | 2021-10-14 | 2023-09-26 | 云南国钛金属股份有限公司 | Preparation method of nuclear-grade zirconia |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN87104300A (en) * | 1986-06-18 | 1987-12-30 | 联邦科学工业研究机构 | From zirconic material, refine high-purity zirconium dioxide |
| CN87100207A (en) * | 1987-01-07 | 1988-07-20 | 上海跃新化工厂 | Produce zirconium white by zircon |
| CN1063268A (en) * | 1991-12-05 | 1992-08-05 | 广西冶金研究所 | Produce zirconium dioxide with the white lime sintering process |
| CN1087604A (en) * | 1993-09-27 | 1994-06-08 | 广西冶金研究院 | From zircon ore concentrate, prepare high-purity zirconium dioxide |
-
1995
- 1995-03-31 CN CN95104103A patent/CN1039805C/en not_active Expired - Fee Related
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN87104300A (en) * | 1986-06-18 | 1987-12-30 | 联邦科学工业研究机构 | From zirconic material, refine high-purity zirconium dioxide |
| CN87100207A (en) * | 1987-01-07 | 1988-07-20 | 上海跃新化工厂 | Produce zirconium white by zircon |
| CN1063268A (en) * | 1991-12-05 | 1992-08-05 | 广西冶金研究所 | Produce zirconium dioxide with the white lime sintering process |
| CN1087604A (en) * | 1993-09-27 | 1994-06-08 | 广西冶金研究院 | From zircon ore concentrate, prepare high-purity zirconium dioxide |
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|---|---|
| CN1132181A (en) | 1996-10-02 |
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| C06 | Publication | ||
| PB01 | Publication | ||
| C53 | Correction of patent for invention or patent application | ||
| CB03 | Change of inventor or designer information |
Inventor after: Zheng Wenyu Inventor before: Zheng Wenyu Inventor before: Zou Qinghua Inventor before: Lai Yuanxiong Inventor before: Chen Damei Inventor before: Ma Xiaoguo |
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| COR | Change of bibliographic data |
Free format text: CORRECT: INVENTOR; FROM: ZHENG WENYU; ZOU QINGHUA; LAI YUANXIONG; CHEN DAMEI; MA XIAOGUO TO: ZHENG WENYU |
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| C14 | Grant of patent or utility model | ||
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Free format text: CORRECT: PATENTEE; FROM: GUANGDONG POLYTECHNICAL COLLEGE TO: GUANGDONG UNIVERSITY OF TECHNOLOGY |
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| CP01 | Change in the name or title of a patent holder |
Patentee after: Guangdong University of Technology Patentee before: Guangdong Polytechnical College |
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| C53 | Correction of patent for invention or patent application | ||
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Free format text: CORRECT: PATENTEE; FROM: GUANGDONG UNIVERSITY OF TECHNOLOGY TO: GUANGDONG ORIENT ZIRCONIC INDUSTRY TECHNOLOGY + SCIENCE CO., LTD. |
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| CP03 | Change of name, title or address |
Address after: 515821 Guangdong Province, Shantou Chenghai city Laimeilu Yutian Science Park Patentee after: Dongfang Zirconium Industry Science-Technology Co., Ltd., Guangdong Address before: 510090 No. 729 Dongfeng East Road, Guangdong, Guangzhou Patentee before: Guangdong University of Technology |
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| C19 | Lapse of patent right due to non-payment of the annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |