CN103920527B - Catalyst and the preparation method and application of 1,2-glycol are prepared in epoxide hydration - Google Patents
Catalyst and the preparation method and application of 1,2-glycol are prepared in epoxide hydration Download PDFInfo
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- CN103920527B CN103920527B CN201410169234.9A CN201410169234A CN103920527B CN 103920527 B CN103920527 B CN 103920527B CN 201410169234 A CN201410169234 A CN 201410169234A CN 103920527 B CN103920527 B CN 103920527B
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Abstract
The present invention relates to catalyst and preparation method and application that 1,2-glycol is prepared in a kind of epoxide hydration.Take Beta zeolite molecular sieve as raw material, make through acid treatment with by roasting introducing activated centre metal, preparation method is, the Beta zeolite molecular sieve after acid treatment is mixed with organo-metallic compound presoma, roasting by metering.The present invention can solve the problems such as the environmental pollution caused in high water ratio, high energy consumption and production process in traditional handicraft.Catalyst carrier of the present invention is cheap and easy to get, catalyst preparation process is simple, have good stability, be applied to epoxide in a mild condition to prepare in the technique of glycol there is excellent catalytic activity and selective, can be used in the industrial production of epoxide hydration glycol.
Description
Technical field
The present invention relates to catalyst and preparation method and application that 1,2-glycol is prepared in a kind of epoxide hydration, is specifically catalyst and the application process that raw material direct hydration prepares 1,2-glycol with epoxide.
Background technology
1,2-glycol, as important Organic Chemicals, is mainly used in synthesizing polyester resin, antifreezing agent, cosmetics, photographic material, lubricant, medicine intermediate and multiple fine chemicals etc.Industrial, it is one of process route with application prospect most that direct catalysis hydration epoxide prepares 1,2-glycol synthetic method.Therefore, in recent years, develop the focus that efficient water-fast catalyst is this research direction always, Ye Shi lot of domestic and foreign scientific research institution and enterprise need a difficult problem of capturing.
In recent decades, in succession developed by Ge great research institution and company for the catalyst series of this reaction of catalysis and Patents technology, wherein major part exploitation mainly concentrates on various solid/liquid class acid base catalysator, comprises sulfuric acid, cyclic organic amine, the resin of cation or anion exchange, the macromolecule organic silicon alkanamine, macrocyclic chelate compound and load metal oxide.Although correlation technique achieves higher glycol yield, also inevitably facing some technological deficiencies: as serious in easily caused equipment corrosion in production process simultaneously, causing production hidden danger; In production process, part diol product dimerization or trimerization and form a large amount of accessory substances under the effect of catalyst, thus adopts the inventory (mol ratio of water and epoxide is greater than 20) adding flood to reach the object of dilution.Although this measure effectively inhibits the formation of by-product, subsequent purification process consumes a large amount of energy, causes production cost significantly to promote.
Summary of the invention
The object of this invention is to provide catalyst and preparation method and application that 1,2-glycol is prepared in a kind of epoxide hydration.The present invention can solve the problem such as high water ratio, high energy consumption and environmental pollution in traditional glycol manufacturing process, this catalyst has stronger acidity and the stability of excellence, prepare in the reaction of glycol at epoxide direct hydration, close to room temperature (40 DEG C) and under the condition of low water ratio (mol ratio of such as water and epoxide is 2) can catalysis obtain excellent catalytic activity and glycol selective.
Provided by the inventionly prepare 1 for epoxide direct hydration, the catalyst of 2-glycol is for raw material with business-like Beta zeolite molecular sieve, make through acid treatment with by roasting introducing activated centre metal, preparation method is, by metering, the Beta zeolite molecular sieve after acid treatment is mixed with organo-metallic compound presoma, roasting.
Described content of metal is the 1-5% of catalyst quality; Described metal is tin, zirconium or titanium; Described acid treatment is red fuming nitric acid (RFNA), hydrochloric acid or oxalic acid treatment; Described organo-metallic compound presoma is dimethyltin chloride, bicyclic pentadiene zirconium dichloride or dicyclic pentylene titanium dichloride;
Described epoxide is 7-oxa-bicyclo[4.1.0, oxirane, expoxy propane, epoxychloropropane, epoxy butane and Styryl oxide; 1,2-described glycol is 1,2-cyclohexanediol, ethylene glycol, 1,2-PD, 3-chlorine-1,2-propylene glycol, 1,2-butanediol and styrene glycol.
The preparation method preparing the catalyst of 1,2-glycol for epoxide direct hydration provided by the invention comprises the steps:
1) by Beta molecular screen primary powder (mol ratio: SiO
2/ Al
2o
3=25-100) process under the condition of concentrated acid (red fuming nitric acid (RFNA), concentrated hydrochloric acid or oxalic acid solution), treatment temperature is 25-150 DEG C, processing time 1-40h;
2) catalyst mixture after acid treatment is carried out decompress filter, after the filter cake obtained is washed to neutrality, constant temperature 12-24 hour in air dry oven, temperature is 80-120 DEG C;
3) mix in grinding with organo-metallic compound presoma, then mixture is placed in Muffle furnace roasting, sintering temperature is 350-650 DEG C, and roasting time is 6-12h;
The application process preparing the catalyst of glycol for epoxide direct hydration provided by the invention comprises the steps:
1) catalyst, epoxide and water are placed in pressure reaction still, airtight, discharge the air in reactor with nitrogen purge reactor, in reactor, then squeeze into nitrogen maintain 1.0Mpa pressure;
2) pressure reaction still is placed in stirring reaction on preheated reactor, can product be obtained.Reaction condition is 40-80 DEG C, and the reaction time is 4-6h.
3) product gas chromatographic analysis.
The mol ratio of epoxide and water is 1: 1-10, and stir speed (S.S.) is 800 revs/min;
The rate of charge of described catalyst and epoxide is 1: 100 (g/mmol).
Acidity of catalyst of the present invention is stronger, can directly apply, preparation process is simple to operation, structural behaviour is stablized, catalyst can in the reaction of epoxide catalysis hydration glycol under the temperate condition close to room temperature and low water ratio, and show excellent catalytic activity and higher glycol selective, just can repeatedly recycle by means of only roasting after reaction terminates, catalytic activity is without obvious decline; This catalyst preparation process is simple, and with low cost, and Catalytic processes is environment friendly and pollution-free, can prepare large-scale promotion application in the reaction of glycol in epoxide hydration.
Accompanying drawing explanation
Fig. 1 is the SEM figure of prepared catalyst.
Fig. 2 is the XRD figure of prepared molecular sieve catalyst.
Fig. 3 is the UV-vis figure of prepared catalyst.
Detailed description of the invention
Below in conjunction with specific embodiment, explanation detailed, complete is further done to the present invention.
Specific experiment method and apparatus involved in following embodiment if no special instructions, is conventional method or implements according to the condition of manufacturer's description suggestion.Involved reagent is commercially available.Beta molecular screen primary powder of the present invention purchased from Shenneng Science-Technology Co., Ltd., Tianjin, silica alumina ratio (SiO
2/ Al
2o
3) be 25-100.
Embodiment 1:
The preparation process of 4%Sn-Beta catalyst used in the present embodiment comprises the steps:
1) by a certain amount of Beta molecular screen primary powder (SiO
2/ A
2o
3=25) be placed in there-necked flask with red fuming nitric acid (RFNA), concentrated hydrochloric acid or oxalic acid solution to mix, in the oil bath reactor of 100 DEG C, heat return stirring 20h.Wherein, the rate of charge of Beta molecular screen primary powder and acid solution is 1: 20 (g/mL);
2) after the solidliquid mixture after return stirring fully being cooled, add deionized water wherein and be diluted to certain concentration, after decompress filter, the filter cake of gained is extremely neutral with the washing of a large amount of deionized waters, be then placed on freeze-day with constant temperature 12h in the air dry oven of 100 DEG C;
3) in glove box, take step 2) in the dimethyltin chloride organic precursor of a certain amount of pressed powder and aequum, after agate mortar grinding fully, be placed in Muffle furnace high-temperature roasting and namely obtain required catalyst.Wherein, sintering temperature is 550 DEG C, and roasting time is 6h.
Conveniently hereafter state, by called after 4%Sn-Beta-X, 4%Sn-Beta-Y and 4%Sn-Beta-C respectively of the molecular sieve through nitric acid, hydrochloric acid and oxalic acid solution process.
4%Sn-Beta catalyst is used for different water to prepare 1,2-cyclohexanediol than 7-oxa-bicyclo[4.1.0 hydration under condition and comprise the steps:
1) by the 4%Sn-Beta catalyst of 0.1g, the 7-oxa-bicyclo[4.1.0 of 10mmol and water drop in the liner of the polytetrafluoroethylene (PTFE) material of pressure reactor, and sealed reactor rinses reactor three times with high pure nitrogen, and in maintenance reactor, pressure is at 1.0Mpa;
2) pressure reactor is placed on preheated reactor, after adding thermal agitation a period of time, can product be obtained.Catalytic reaction condition is: reaction temperature is 40 DEG C, and the reaction time is 6h, and the mol ratio of epoxide and water is 1: 2, and stir speed (S.S.) is 800 revs/min;
3) product gas chromatographic analysis.Gas-chromatography used is Shimadzu 2010 gas chromatograph, and collocation fid detector, capillary chromatograph model is AgilentHP-5MS.Adopt temperature programming to be separated product, heating step is as follows: initial temperature is 80 DEG C, insulation 3min, then with the ramp to 250 DEG C of 15 DEG C/min, and insulation 5min.Utilize internal standard method to ask by chromatographic work station and calculate the conversion ratio of raw material and the selective of target product.Catalytic performance test the results are shown in Table 1:
The different acid treatment of table 1 changes the impact of hexylene glycol technique to 7-oxa-bicyclo[4.1.0 hydration preparation
Catalytic performance test result shows: the sample after dissimilar acid treatment, and it is the conversion ratio of 7-oxa-bicyclo[4.1.0 and the obvious difference of selective existence of cyclohexanediol under the same reaction conditions.Catalyst sample through nitric acid treatment shows the most excellent catalytic activity in the reaction of catalysis 7-oxa-bicyclo[4.1.0 hydration, and the productive rate of glycol is up to 83.6%.
Embodiment 2:
The acid used of the present embodiment process molecular screen primary powder is nitric acid, and under having investigated 100 DEG C for the treatment of temperatures, nitric acid treatment different time sections is on the impact of 4%Sn-Beta catalyst on catalysis 7-oxa-bicyclo[4.1.0 hydration performance, and catalytic performance test is in table 2:
Table 2 nitric acid treatment different time sections prepares the impact of cyclohexanediol technique on 7-oxa-bicyclo[4.1.0 hydration
Catalytic performance test result shows: along with the increase of nitric acid treatment time, the conversion ratio of 7-oxa-bicyclo[4.1.0 and the selective of target product are improved all accordingly, 20h is reached when the acid treatment time, the productive rate of glycol is 83.6% to the maximum, continue to extend the acid treatment time, to reaction effect without obvious facilitation.
Embodiment 3:
The present embodiment investigates the impact of different organometallic precursors on catalysis 7-oxa-bicyclo[4.1.0 hydration performance, and other reaction conditions are with described in embodiment 2.Catalytic performance test the results are shown in Table 3:
The different organometallic precursor of table 3 prepares the impact of cyclohexanediol technique on 7-oxa-bicyclo[4.1.0 hydration
Catalytic performance test result shows: different catalytic active centers shows obvious difference to reacting catalytic performance, compare bicyclic pentadiene zirconium dichloride and dicyclic pentylene titanium dichloride, the 4%Sn-Beta catalyst activity obtained by dimethyltin chloride roasting is best, also shows excellent catalytic selectivity simultaneously.
Implementation column 4:
The present embodiment object is that the percentage composition investigating tin is on the impact of catalysis 7-oxa-bicyclo[4.1.0 hydration performance, and other reaction conditions are with described in embodiment 3.Catalytic performance test the results are shown in Table 4:
Table 4 different tin content prepares the impact of cyclohexanediol technique to 7-oxa-bicyclo[4.1.0 hydration
Catalytic performance test result shows: in catalyst, Theil indices also has obvious impact to catalytic performance.When Theil indices is increased to 4% from 2%, the conversion ratio of 7-oxa-bicyclo[4.1.0 obviously increases, and reaches 90.2mol%, when continuing to increase Theil indices to 5%, and the conversion ratio of 7-oxa-bicyclo[4.1.0 and cyclohexanediol is selective does not rise appreciably.
Embodiment 5:
The present embodiment has investigated different water than under condition, and 4%Sn-Beta catalyst is on the impact of catalysis 7-oxa-bicyclo[4.1.0 hydration performance, and other reaction conditions are with described in embodiment 4.Catalytic performance test the results are shown in Table 5:
The impact of cyclohexanediol technique is prepared in the hydration of table 5 different water comparison 7-oxa-bicyclo[4.1.0
Catalytic performance test result shows: along with the increase of water inventory, and the conversion ratio of 7-oxa-bicyclo[4.1.0 also increases thereupon, and the selective raising of glycol is not obvious.Meanwhile, after the water yield increases, highlight the later stage except water extracting alcohol glycol process energy consumption problem, therefore consider, when the mol ratio of water and 7-oxa-bicyclo[4.1.0 is 2: 1, the productive rate of glycol reaches 83.6%, is desirable process conditions.
Embodiment 6:
The present embodiment has been investigated under optimum reaction condition, and 4%Sn-Beta catalyst application recycles effect in catalysis 7-oxa-bicyclo[4.1.0 hydration reaction.Catalyst often through once circulation after, in Muffle furnace after roasting for reacting next time.Reaction condition is: reaction temperature is 40 DEG C, and the reaction time is 6h, and the mol ratio of water and 7-oxa-bicyclo[4.1.0 is 2: 1, N
2pressure is 1.0Mpa, and stir speed (S.S.) is 800 turns/min, and sintering temperature is 550 DEG C.Catalyst circulation uses and the results are shown in Table 6:
Table 6 catalyst circulation result of use
Catalytic performance test result shows: under optimum reaction condition, and after catalyst recycles through at least 5 times, its catalytic performance does not decline.
Embodiment 7:
The present embodiment has investigated the catalytic performance of other epoxy substrates of 4%Sn-Beta catalyst, and reaction temperature is 40 DEG C, and the mol ratio of water and epoxide is 2: 1.
Table 7 catalyst is to the catalytic effect of different epoxy substrate
Catalytic performance test result shows: this catalyst applied widely, under the condition of lower temperature and low water ratio, the conversion ratio of various epoxy substrate and glycol selective all higher.
Claims (10)
1. one kind for epoxide direct hydration system 1, the catalyst of 2-glycol, it is characterized in that it is take Beta zeolite molecular sieve as raw material, make through acid treatment with by roasting introducing activated centre metal, preparation method is, by metering, the Beta zeolite molecular sieve after acid treatment is mixed with organo-metallic compound presoma, roasting; Described content of metal is the 1-5% of catalyst quality; Described metal is tin or zirconium.
2. catalyst according to claim 1, is characterized in that described acid treatment is red fuming nitric acid (RFNA), hydrochloric acid or oxalic acid treatment.
3. catalyst according to claim 1, is characterized in that described organo-metallic compound presoma is dimethyltin chloride or bicyclic pentadiene zirconium dichloride.
4. catalyst according to claim 1, is characterized in that described epoxide is 7-oxa-bicyclo[4.1.0, oxirane, expoxy propane, epoxychloropropane, epoxy butane or Styryl oxide.
5. catalyst according to claim 1, is characterized in that 1,2-described glycol is 1,2-cyclohexanediol, ethylene glycol, 1,2-PD, 3-chlorine-1,2-propylene glycol, 1,2-butanediol and styrene glycol.
6. an epoxide direct hydration according to claim 1 prepares the preparation method of the catalyst of 1,2-glycol, it is characterized in that comprising the steps:
1) processed under the condition of concentrated acid by Beta molecular screen primary powder, treatment temperature is 25-150 DEG C, processing time 1-40h; SiO
2/ Al
2o
3=25-100;
2) catalyst mixture after acid treatment is carried out decompress filter, after the filter cake obtained is washed to neutrality, constant temperature 12-24 hour in air dry oven, temperature is 80-120 DEG C;
3) mix in grinding with organo-metallic compound presoma, then mixture is placed in Muffle furnace roasting, sintering temperature is 350-650 DEG C, and roasting time is 6-12h.
7. method according to claim 6, is characterized in that described acid treatment is red fuming nitric acid (RFNA), hydrochloric acid or oxalic acid treatment.
8. method according to claim 6, is characterized in that described organo-metallic compound presoma is dimethyltin chloride or bicyclic pentadiene zirconium dichloride.
9. method according to claim 6, is characterized in that described SiO
2/ A
2o
3=25.
10. the application process of the catalyst described in any one of claim 1-5, is characterized in that comprising the steps:
1) catalyst, epoxide and water are placed in pressure reaction still, airtight, discharge the air in reactor with nitrogen purge reactor, in reactor, then squeeze into nitrogen maintain 1.0Mpa pressure;
2) pressure reaction still is placed in stirring reaction on preheated reactor, can product be obtained; Reaction condition is 40-80 DEG C, and the reaction time is 4-6h;
3) product gas chromatographic analysis;
The mol ratio of epoxide and water is 1: 1-10, and stir speed (S.S.) is 800 revs/min.
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| CN104437607B (en) * | 2014-11-06 | 2016-06-29 | 南开大学 | Stanniferous molecular sieve catalyst and the using method of ethylene glycol is prepared for ethylene oxide hydration |
| CN104892365B (en) * | 2015-05-27 | 2017-06-27 | 泰山医学院 | A kind of method of LP synthesizing high-purity glycerin chlorohydrin |
| CN106824259B (en) * | 2016-12-21 | 2019-07-12 | 南开大学 | The molecular sieve catalyst of yttrium containing zinc, preparation method and the application method of 1,3- butadiene are prepared for ethyl alcohol conversion |
| CN108097300B (en) * | 2017-12-15 | 2020-06-05 | 南开大学 | Catalyst for preparing isobutene by acetic acid conversion and preparation method thereof |
| CN108129260B (en) * | 2017-12-21 | 2021-06-08 | 常州南京大学高新技术研究院 | Synthesis method of phenyl ethylene glycol |
| CN108855207B (en) * | 2018-06-17 | 2021-04-27 | 复旦大学 | Heteroatom Beta zeolite catalyst containing alkali metal and preparation method and application thereof |
| CN110354899A (en) * | 2019-08-22 | 2019-10-22 | 华东师范大学 | A kind of solid acid catalyst and preparation method and the application in epoxide hydration |
| CN111939975B (en) * | 2020-08-24 | 2023-03-28 | 南开大学 | Bifunctional molecular sieve catalyst for directly preparing 1,2-diol by catalyzing olefin and application thereof |
| CN115722259B (en) * | 2021-08-26 | 2024-02-09 | 中国科学院广州能源研究所 | Synthesis method of space adjacent bimetallic heteroatom molecular sieve |
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| EP0943594B1 (en) * | 1998-02-24 | 2003-04-09 | Fina Technology, Inc. | Aromatic alkylation process |
| CN102039171A (en) * | 2009-10-13 | 2011-05-04 | 中国石油化工股份有限公司 | Preparation method of non-binder ZSM-5/zeolite beta coexisting molecular sieve catalyst |
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