CN103120934A - Method for preparing TiO2/SiO2 catalyst for exchanging and synthesizing diphenyl carbonate by dimethyl carbonate and phenol ester - Google Patents
Method for preparing TiO2/SiO2 catalyst for exchanging and synthesizing diphenyl carbonate by dimethyl carbonate and phenol ester Download PDFInfo
- Publication number
- CN103120934A CN103120934A CN2011103558444A CN201110355844A CN103120934A CN 103120934 A CN103120934 A CN 103120934A CN 2011103558444 A CN2011103558444 A CN 2011103558444A CN 201110355844 A CN201110355844 A CN 201110355844A CN 103120934 A CN103120934 A CN 103120934A
- Authority
- CN
- China
- Prior art keywords
- catalyst
- titanium
- carbonate
- phenol
- ester exchange
- 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.)
- Pending
Links
Landscapes
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)
- Catalysts (AREA)
Abstract
A method for preparing TiO2/SiO2 catalyst for exchanging and synthesizing diphenyl carbonate by dimethyl carbonate and phenol ester includes: utilizing SiO2 as a carrier and TiO2 as an active component, utilizing urea as additives and diacetone as inhibitor, and roasting after dissolving and gelling, wherein the titanium and silicon mole ratio is 1:1-60. The method mainly solves the problem about low ester exchange yield of multi-phase catalyst. The TiO2/SiO2 catalyst prepared by the method has higher catalytic activity and ester exchange selectivity for exchanging and synthesizing diphenyl carbonate by dimethyl carbonate and phenol ester, phenol transformation rate can reach 42.9%, overall selectivity of ester exchange products (methyl phenyl carbonate and diphenyl carbonate) is larger than 99.9%, and byproducts are not detected. The method for preparing TiO2/SiO2 catalyst for exchanging and synthesizing diphenyl carbonate by dimethyl carbonate and phenol ester is simple and short in preparation time, and raw materials therefore are low in cost and easy to obtain.
Description
Technical field
The present invention discloses a kind of preparation method of the heterogeneous catalyst for dimethyl carbonate and phenol ester exchange synthesizing diphenyl carbonate.
Background technology
Diphenyl carbonate (DPC) is a kind of important chemical intermediate, low toxicity, pollution-free.Can be by the synthetic many organic compounds of the reactions such as halogenation, nitrated, hydrolysis, ammonia solution and macromolecular material, phosgene and the bisphenol-A that particularly can substitute severe toxicity synthesize the polycarbonate of function admirable by melt transesterification.Synthetic main phosgenation, oxidative carbonylation and the ester-interchange method of adopting of DPC.Phosgenation just progressively is eliminated due to severe toxicity and the severe corrosive of raw material.The oxidative carbonylation atom utilization is high, but the prices such as major catalyst precious metals pd are expensive, and exists phenol easily to be oxidized to other accessory substance, and the shipwreck that reaction generates is the problem such as to remove.Ester-interchange method comprises that carboxylate is that raw material and phenol are the ester-interchange method of raw material, need to first pass through the conversion of phenol due to the carboxylate raw material, all adopts homogeneous catalyst, and this paper does not do introduction.Ester-interchange method refers generally to the ester-interchange method take phenol as raw material, comprises the ester exchange of phenol and dimethyl oxalate (DMO) and the ester exchange of phenol and dimethyl carbonate (DMC), meets the reaction principle of atom economy.Ester exchange take phenol as raw material is mainly take the organic compound of titanium and tin as homogeneous catalyst, and is active high, selective high, but catalyst is unstable, and reclaims difficulty with product separation, therefore, develops highly active heterogeneous catalyst and has important practical significance.
Tong Dongshen etc. (J.Mol.Catal.A:Chem., 2006,268:120-126) with NH
4VO
3The V that obtains 550 ℃ of calcinings
2O
5Activity is the highest, and the conversion ratio of phenol and ester exchange selectively are respectively 42.0% and 95.5%.Simultaneously, they (Journal of Catalysis, 2006,28 (3): the V-Cu composite oxides that 190-192) prepare with coprecipitation, the conversion ratio of phenol is 37.0%, ester exchange is selectively 96.8%.This catalyst advantage is that inactivation is slow, and by after calcination and regeneration, its activity is recovered fully, and is suitable with fresh catalyst.The Pb that Zhou Weiqing (Appl.Catal.A, 2004) prepares with coprecipitation equally
3O
4-ZnO O composite metallic oxide catalyst [17] activity is very high, and phenol conversion reaches 64.6%, but ester exchange is only selectively 72.0%, has the accessory substances such as a large amount of methyl phenyl ethers anisoles and methylbenzene to generate.And catalyst is repeated bad, uses for the second time the yield of DPC just to drop to 24.3%, can not regenerate.
Kim (J.Caltal.Lett., 1999, the TiO of preparation such as 59:83-88)
2/ SiO
2Catalyst reacts under the 773K meteorological condition, and the yield of DPC is 37.2%, and ester exchange is selectively 86.8%.In CN101254460, adopt the TiO of infusion process preparation
2/ SiO
2, the conversion ratio of phenol reaches 48.6%, and ester exchange selectively reaches 99.6%.Cao Min etc. (J.Catal.Communication, 2005,6:802-807) prepare PbO/MgO (PbO-10wt%) catalyst with infusion process, with active raising the after oxygen treatments applied, the conversion ratio of phenol is 36.8%, ester exchange is selectively 99.5%.At 460 ℃ of logical oxygen treatments applied 4h, the conversion ratio of phenol is 32.9% with used catalyst, and ester exchange is selectively 99.7%.(Sichuan University's journal, 2002,34 (5): 39-41) the homogeneous catalyst load is obtained n-Bu such as Zhou Weiqing
2SnO/SiO
2(n-Bu2SnO-10wt%) on catalyst, the yield of DPC is 21.8%, lower than the n-Bu of load not
2SnO (yield of DPC is 32.8%).And sintering temperature higher than 423K after, because butyl group disappears and SnO
2Crystalline phase produces, and the reactivity of catalyst sharply descends, and the yield of DPC is less than 1.6%.Yu Qinqin (SCI, 2005,26 (8): 1502-1506) etc. the conversion ratio of the Zn-Al-hydrotalcite DMC of preparation reaches 55.9%, ester exchange offspring be selectively 93.6%.(the Organic process Research such as Mei Fuming; Development, 2004,8:372-375) conversion ratio of Mg-Al-hydrotalcite DMC and ester exchange selectively reach respectively 31.9% and 82.4%.Chen Tong etc. (catal.communications, 2007,8:1361-1365) adopting the heteropoly compound with Keggin structure is catalyst, the yield of ester exchange offspring and selectively can reach respectively 30% and 99%.
(fine chemistry industry, 2005,22 (2): 115-118) replace the micro porous molecular sieve Ti-β of preparation by the isomorphous, the conversion ratio of phenol is 20.3% to Zhang Shudong etc., and ester exchange is only selectively 53.3%.Luo Shuwen etc. (Chinese J.Catal., 2007,28 (11): 937-939) with the heteroatom mesopore molecular sieve Me-HMS catalyst of hydrothermal synthesis method preparation, wherein Ti-HMS shows best catalytic performance; The conversion ratio of phenol is 31.4%, and ester exchange is selectively 99.9%, accessory substance do not detected.(J.Mol.Catal.A:Chem., 2008, the 289:100-105) MoO of preparation such as Li Zhenhua
3/ SiMCM-41 catalyst, the MPC that calculates with DMC and the yield of DPC are respectively 39.6% and 2.6%, ester exchange be selectively 96.9%.
Summary of the invention
The purpose of this invention is to provide a kind of preparation method for dimethyl carbonate and phenol ester exchange synthesizing diphenyl carbonate heterogeneous catalyst, make prepared TiO
2/ SiO
2Catalyst has high activity and high selectivity under relatively mild liquid-phase reaction condition, can reduce the catalyst preparation cost simultaneously.
Technical scheme of the present invention: with SiO
2Be carrier, TiO
2Be active component, in its component, the titanium silicon mol ratio is 1: 60～1: 1, and preferred molar ratio is for than being 1: 30～1: 2; And take urea as additive, acetylacetone,2,4-pentanedione is the method preparation of inhibitor.
The preparation method of heterogeneous catalyst of the present invention is as follows:
(1) take titanium source and acetylacetone,2,4-pentanedione, be placed in aqueous solution of urea, get solution A;
(2) take the silicon source, add in solution A;
(3) with mentioned solution HNO
3After regulating pH value, stir, 50 ℃ of lower ageing 2-48h;
(4) filter above-mentioned solid at 200～800 ℃ of lower roasting 2～6h.
The titanium source of adopting in method can be organic titanic compound, comprises butyl titanate, tetraethyl titanate, tetraisopropyl titanate, tetraphenyl titanate and cyclopentadienyl titanium dichloride; Also inorganic titanium compound be can be, titanium tetrachloride, titanium trichloride, titanium tetrafluoride and titanyl sulfate comprised.
In the aqueous solution of urea that adopts in method, the mol ratio of urea and water is (2: 1)～(1: 10).
The present invention has following features:
(1) the inventive method preparation method is simple and preparation time is short, only take urea as additive, does not use template, and raw material is cheap and easy to get.
(2) TiO of the inventive method preparation
2/ SiO
2Catalyst is used for the reaction of dimethyl carbonate and phenol ester exchange synthesizing diphenyl carbonate, under relatively mild liquid-phase reaction condition, has higher catalytic activity and ester exchange offspring (methyl benzol carbonate and diphenyl carbonate) selectively.
(3) TiO of the inventive method preparation
2/ SiO
2Catalyst is used for the reaction of dimethyl carbonate and phenol ester exchange synthesizing diphenyl carbonate, is easy to separate, recovery, can etching apparatus, do not pollute the environment yet, and belong to green catalyst; And needed raw material is cheap and easy to get, and cost is low, and the preparation method is simple.
The specific embodiment
Embodiment 1
Get 9g urea and be dissolved in 10.8g H
2In O, add acetylacetone,2,4-pentanedione and butyl titanate after stirring, stirring at normal temperature 3h.After adding ethyl orthosilicate, with HNO
3Regulator solution PH (mol ratio of Ti/Si is 1: 20, and the mol ratio of acetylacetone,2,4-pentanedione and butyl titanate is 3: 5); After gel ageing 2h in 50 ℃ of lower evaporate to dryness volatile components.600 ℃ of calcining 4h.
Embodiment 2
Carry out the ester exchange reaction of dimethyl carbonate and phenol with the catalyst of embodiment 1 preparation
(1) in being connected with wireway and thermometer, constant pressure funnel and being equipped with the there-necked flask of rectifying column, add catalyst 1.0 grams of embodiment 1;
(2) pass under nitrogen, add phenol 15 grams;
When (3) being heated to 180 ℃, begin to drip dimethyl carbonate (DMC), the total amount that adds DMC is 13.5ml.Reacted 9.0 hours, and constantly steamed the mixed fraction of methyl alcohol and dimethyl carbonate in course of reaction by rectifying column;
(4) mixed fraction is all used the analysis of Shimadzu GC-14B gas chromatograph with the reactant liquor that contains principal product methyl benzol carbonate and diphenyl carbonate, normalization method is quantitative with proofreading and correct, record: the conversion ratio of phenol is 38.3%, the yield of methyl benzol carbonate and diphenyl carbonate is respectively 23.1% and 15.2%, ester exchange overall selectivity 99.9% does not detect accessory substance.
Embodiment 3
The preparation process of catalyst is with embodiment 1, but change TiO
2With SiO
2Mol ratio, as shown in table 2.Carry out the ester exchange reaction of dimethyl carbonate and phenol with the catalyst that makes, reaction condition is identical with embodiment 2, and its activity the results are shown in Table 1.
Table 1 different Ti O
2/ SiO
2Mol ratio on the impact of catalyst activity
* MPC-methyl benzol carbonate, the DPC-diphenyl carbonate
Embodiment 4
The preparation process of catalyst is with embodiment 1, but the change sintering temperature is as shown in table 2.Carry out the ester exchange reaction of dimethyl carbonate and phenol with the catalyst that makes, reaction condition is identical with embodiment 2, and its activity the results are shown in Table 2.
The impact of the different sintering temperatures of table 2 on catalyst activity
* MPC-methyl benzol carbonate, the DPC-diphenyl carbonate.
Claims (4)
1. TiO who is used for ester exchange synthesizing diphenyl carbonate
2/ SiO
2The preparation method of catalyst, described catalyst Ti silicon mol ratio is 1: 60～1: 1, it is characterized in that take urea as organic additive, acetylacetone,2,4-pentanedione is inhibitor, preparation process is as follows:
(1) urea is dissolved in deionized water, adds titanium source and acetylacetone,2,4-pentanedione, then add the silicon source, regulate pH value between 0～10, fully mix;
(2) mentioned solution is dry after 30～120 ℃ of heating 1～12h, then be placed in Muffle furnace in 200～800 ℃ of lower roasting 2～6h; Namely make TiO
2/ SiO
2Catalyst.
2. method according to claim 1, it is characterized in that the titanium source is organic titanic compound or inorganic titanium compound, organic titanic compound is butyl titanate, tetraethyl titanate, tetraisopropyl titanate, tetraphenyl titanate or cyclopentadienyl titanium dichloride, and inorganic titanium compound is titanium tetrachloride, titanium trichloride, titanium tetrafluoride or titanyl sulfate.
3. method according to claim 1, is characterized in that titanium source and acetylacetone,2,4-pentanedione mol ratio are (1: 3)～(5: 1); The mol ratio of urea and deionized water is (2: 1)～(1: 10).
4. method according to claim 1 is characterized in that titanium source and acetylacetone,2,4-pentanedione can first mix afterwards to add, or directly successively adds.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2011103558444A CN103120934A (en) | 2011-11-11 | 2011-11-11 | Method for preparing TiO2/SiO2 catalyst for exchanging and synthesizing diphenyl carbonate by dimethyl carbonate and phenol ester |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2011103558444A CN103120934A (en) | 2011-11-11 | 2011-11-11 | Method for preparing TiO2/SiO2 catalyst for exchanging and synthesizing diphenyl carbonate by dimethyl carbonate and phenol ester |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN103120934A true CN103120934A (en) | 2013-05-29 |
Family
ID=48452186
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2011103558444A Pending CN103120934A (en) | 2011-11-11 | 2011-11-11 | Method for preparing TiO2/SiO2 catalyst for exchanging and synthesizing diphenyl carbonate by dimethyl carbonate and phenol ester |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN103120934A (en) |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104861160A (en) * | 2013-12-30 | 2015-08-26 | 中国科学院成都有机化学有限公司 | Method for preparing aliphatic polycarbonate through melt transesterification and polycondensation |
| CN105327709A (en) * | 2014-08-15 | 2016-02-17 | 陕西延长石油（集团）有限责任公司 | Preparation method of catalyst used for synthesizing diphenyl carbonate by ester exchange method |
| CN107029692A (en) * | 2016-01-25 | 2017-08-11 | 中国科学院成都有机化学有限公司 | A kind of preparation method of ester exchange synthesizing diphenyl carbonate CNT Quito phase catalyst |
| CN110128274A (en) * | 2019-05-28 | 2019-08-16 | 中国科学院成都有机化学有限公司 | A kind of method of dimethyl carbonate ester exchange synthesizing diphenyl carbonate |
| CN110252274A (en) * | 2019-06-14 | 2019-09-20 | 湖北三宁碳磷基新材料产业技术研究院有限公司 | The preparation method of ester exchange synthesizing diphenyl carbonate catalyst |
| CN110642718A (en) * | 2019-09-06 | 2020-01-03 | 湖北三宁碳磷基新材料产业技术研究院有限公司 | Heterogeneous catalyst for synthesizing diphenyl carbonate and preparation method thereof |
| CN110894204A (en) * | 2018-09-11 | 2020-03-20 | 中国石油化工股份有限公司 | Catalyst for preparing diphenyl carbonate compound and preparation method and application thereof |
| CN111097530A (en) * | 2018-10-25 | 2020-05-05 | 中国石油化工股份有限公司 | Catalyst for preparing diphenyl carbonate, preparation and application |
| CN111744540A (en) * | 2020-06-09 | 2020-10-09 | 湖北三宁碳磷基新材料产业技术研究院有限公司 | Solid acid catalyst and application thereof in esterification reaction |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1583247A (en) * | 2004-05-25 | 2005-02-23 | 天津大学 | Preparation for composite titanium oxide catalyst of ester interchange synthetic phenyl ester oxalate |
| CN1970149A (en) * | 2006-12-07 | 2007-05-30 | 天津大学 | Bergmeal particle loaded nano TiO2 preparation method |
| CN101130159A (en) * | 2007-09-20 | 2008-02-27 | 中国科学院广州地球化学研究所 | Method for producing interpose porus titanium dioxide photocatalyst by hydro-thermal method in weak acid condition |
| CN101254460A (en) * | 2008-03-26 | 2008-09-03 | 中国科学院成都有机化学有限公司 | Process for preparing multiphase catalysts for ester exchange synthesizing diphenyl carbonate |
| CN101428209A (en) * | 2007-11-08 | 2009-05-13 | 北京化工大学 | Nano-fibre supported titanium dioxide photocatalyst and preparation method thereof |
-
2011
- 2011-11-11 CN CN2011103558444A patent/CN103120934A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1583247A (en) * | 2004-05-25 | 2005-02-23 | 天津大学 | Preparation for composite titanium oxide catalyst of ester interchange synthetic phenyl ester oxalate |
| CN1970149A (en) * | 2006-12-07 | 2007-05-30 | 天津大学 | Bergmeal particle loaded nano TiO2 preparation method |
| CN101130159A (en) * | 2007-09-20 | 2008-02-27 | 中国科学院广州地球化学研究所 | Method for producing interpose porus titanium dioxide photocatalyst by hydro-thermal method in weak acid condition |
| CN101428209A (en) * | 2007-11-08 | 2009-05-13 | 北京化工大学 | Nano-fibre supported titanium dioxide photocatalyst and preparation method thereof |
| CN101254460A (en) * | 2008-03-26 | 2008-09-03 | 中国科学院成都有机化学有限公司 | Process for preparing multiphase catalysts for ester exchange synthesizing diphenyl carbonate |
Cited By (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104861160A (en) * | 2013-12-30 | 2015-08-26 | 中国科学院成都有机化学有限公司 | Method for preparing aliphatic polycarbonate through melt transesterification and polycondensation |
| CN105327709A (en) * | 2014-08-15 | 2016-02-17 | 陕西延长石油（集团）有限责任公司 | Preparation method of catalyst used for synthesizing diphenyl carbonate by ester exchange method |
| CN105327709B (en) * | 2014-08-15 | 2017-11-17 | 陕西延长石油（集团）有限责任公司 | A kind of preparation method of catalyst for ester-interchange method diphenyl carbonate synthesis |
| CN107029692A (en) * | 2016-01-25 | 2017-08-11 | 中国科学院成都有机化学有限公司 | A kind of preparation method of ester exchange synthesizing diphenyl carbonate CNT Quito phase catalyst |
| CN110894204A (en) * | 2018-09-11 | 2020-03-20 | 中国石油化工股份有限公司 | Catalyst for preparing diphenyl carbonate compound and preparation method and application thereof |
| CN110894204B (en) * | 2018-09-11 | 2022-05-24 | 中国石油化工股份有限公司 | Catalyst for preparing diphenyl carbonate compound and preparation method and application thereof |
| CN111097530A (en) * | 2018-10-25 | 2020-05-05 | 中国石油化工股份有限公司 | Catalyst for preparing diphenyl carbonate, preparation and application |
| CN111097530B (en) * | 2018-10-25 | 2023-03-03 | 中国石油化工股份有限公司 | Catalyst for preparing diphenyl carbonate, preparation and application |
| CN110128274A (en) * | 2019-05-28 | 2019-08-16 | 中国科学院成都有机化学有限公司 | A kind of method of dimethyl carbonate ester exchange synthesizing diphenyl carbonate |
| CN110128274B (en) * | 2019-05-28 | 2022-02-22 | 中国科学院成都有机化学有限公司 | Method for synthesizing diphenyl carbonate by dimethyl carbonate ester exchange |
| CN110252274B (en) * | 2019-06-14 | 2022-09-02 | 湖北三宁碳磷基新材料产业技术研究院有限公司 | Preparation method of catalyst for synthesizing diphenyl carbonate by ester exchange |
| CN110252274A (en) * | 2019-06-14 | 2019-09-20 | 湖北三宁碳磷基新材料产业技术研究院有限公司 | The preparation method of ester exchange synthesizing diphenyl carbonate catalyst |
| CN110642718A (en) * | 2019-09-06 | 2020-01-03 | 湖北三宁碳磷基新材料产业技术研究院有限公司 | Heterogeneous catalyst for synthesizing diphenyl carbonate and preparation method thereof |
| CN111744540A (en) * | 2020-06-09 | 2020-10-09 | 湖北三宁碳磷基新材料产业技术研究院有限公司 | Solid acid catalyst and application thereof in esterification reaction |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103120934A (en) | Method for preparing TiO2/SiO2 catalyst for exchanging and synthesizing diphenyl carbonate by dimethyl carbonate and phenol ester | |
| US9550729B2 (en) | Mixed metal oxide catalysts | |
| CN107866241B (en) | Catalyst for preparing pyromellitic anhydride by oxidizing durene | |
| CN1035320C (en) | Process for producing hydrogen peroxide | |
| KR101065242B1 (en) | Scr denitrification catalyst and the fabrication method thereof using titania hydrate slurry | |
| CN104860810A (en) | Organic titanium catalyst for exchange reaction of dimethyl carbonate and phenol ester | |
| JPH0524866B2 (en) | ||
| CN101254460B (en) | Process for preparing multiphase catalysts for ester exchange synthesizing diphenyl carbonate | |
| JP2006061905A (en) | Catalyst for synthesizing dimethyl carbonate from urea and methanol, manufacturing method of the same and application | |
| WO2016188989A1 (en) | Process for the preparation of titania/metal vanadate based catalyst compositions | |
| CN1803282B (en) | Bimetal composite oxide catalyst for change of methyl carbonate and phenol ester | |
| KR20130074843A (en) | Catalyst for reforming of methane with the enhanced stability for sulfur components, preparing method thereof and methane reforming method using the catalyst | |
| CN101412674A (en) | Method for synthesizing diphenyl carbonate by heterogeneous interesterification | |
| EP3189892B1 (en) | Catalyst for glycerin dehydration, preparation method therefor, and acrolein preparation method using catalyst | |
| JP7292703B2 (en) | Method for producing visible-light-responsive bismuth vanadate | |
| CN1112965C (en) | Catalyst contg. platinum group metal and produced in sol-gel method, as well as method for producing diarylcarbonates | |
| CN106140133B (en) | A kind of method of methyl benzol carbonate disproportionation diphenyl carbonate synthesis | |
| CN104689818A (en) | ZnO/Ag@AgInO2 heterogeneous Z type photocatalytic material and preparation method thereof | |
| CN106560239B (en) | A kind of catalyst and its preparation method and application of catalytic chlorination hydroxide | |
| CN102091637B (en) | Heterogeneous catalyst used in reaction of synthesizing vanillin and preparation method thereof | |
| CN109678713B (en) | Method for preparing diphenyl carbonate by ester exchange | |
| CN102295581A (en) | Method for preparing 3,4-dichlorobenzonitrile by ammonia oxidation | |
| CN101468315B (en) | Method for preparing multiphase catalyst for exchange reaction of dimethyl carbonate and phenol ester | |
| CN107029692A (en) | A kind of preparation method of ester exchange synthesizing diphenyl carbonate CNT Quito phase catalyst | |
| CN102513082A (en) | ZnO co-catalyst with regular shape and preparation method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C12 | Rejection of a patent application after its publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20130529 |