CN109806863A - The preparation of Au catalyst and its application in oxidative dehydrogenation of cyclonexane reaction - Google Patents
The preparation of Au catalyst and its application in oxidative dehydrogenation of cyclonexane reaction Download PDFInfo
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- CN109806863A CN109806863A CN201711157200.8A CN201711157200A CN109806863A CN 109806863 A CN109806863 A CN 109806863A CN 201711157200 A CN201711157200 A CN 201711157200A CN 109806863 A CN109806863 A CN 109806863A
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- catalyst
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- oxidative dehydrogenation
- aurosol
- cyclohexene
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Abstract
The present invention provides a kind of Au catalyst, is support type, including carrier, active group parting；With NaBH4As reducing agent, using PVA as protective agent, at room temperature, HAuCl is restored4Solution obtains aurosol, after being placed at room temperature for 0.5-10 hours, aurosol is supported on carrier under stirring conditions, after filtration washing, vacuum drying, it is roasted 4-8 hours under 250-500 DEG C of air conditions, obtains load type nano gold catalyst, carrier is titanium oxide or titanium oxide.The Au catalyst preparation process that the present invention uses is simple, repeats, and has very high oxidative dehydrogenation of cyclonexane activity (being greater than 50%) and very high cyclohexene selectivity (being greater than 50%).Catalyst has extraordinary stability simultaneously, and 100h or more can be used continuously, and activity is not substantially reduced.
Description
Technical field
The present invention relates to a kind of preparation of Au catalyst and its applications in oxidative dehydrogenation of cyclonexane reaction, belong to catalysis
Agent preparation technical field.
Background technique
Cyclohexene is that one kind is colourless, there is the liquid of specific stimulation smell, is a kind of important industrial chemicals, is widely applied
With medicine, food, agricultural chemicals, the production of feed and other fine chemical products.Such as synthetic lysine, phenol, polycyclic alkene
Resin, rubber chemicals etc..It can be additionally used for the stabilizer of catalyst solvent and petroleum extn agent and high-knock rating gasoline
Deng.After preparing adipic acid by cyclohexene and being succeeded, cyclohexene is considered as synthesizing cyclohexanone, cyclohexanol and adipic acid
Optimum feed stock.
Currently, industrially the method for production cyclohexene is mainly the following method: 1) cyclohexanol catalytic dehydration, the party
Method is using phosphoric acid or sulfuric acid as catalyst, liquid-phase dehydration cyclohexanol production cyclohexene.This process route have been relatively mature, but
It is that product yield is not high in reaction process, side reaction is extremely more, and it is serious to be carbonized in reaction process, also extremely tight to the corrosion of equipment
Weight.It is not suitable for industrial production.2) prepared from benzene and hydrogen is for cyclohexene.This method is with modified silica, aluminium oxide and zeolite etc.
As carrier, using noble metal Ru as the active component of reaction.Wherein, CN1597099A patent describes Ru/ZrO2 conduct and urges
Agent realizes the selective hydrogenation of benzene to cyclohexene in autoclave, and raw material selectivity and selectivity of product are all high, but
It is that such catalyst is easily poisoned, leads to catalyst inactivation.3) cyclohexane liquid-phase oxidation cyclohexene.This method in pyridine with
CuCl2 is as catalyst, using tert-butyl hydroperoxide as the selective oxidation of oxidant realization hexamethylene to cyclohexene.The reaction
There is more side reaction, has seriously affected product cost.
Summary of the invention
The purpose of the present invention is to provide a kind of efficient, stable Au catalysts, prepare hexamethylene applied to cyclohexane oxidation
The reaction process of alkene has high catalytic reaction activity and high selectivity of product.
To achieve the above object, the technical scheme adopted by the invention is as follows:
1. a kind of Au catalyst, the Au catalyst is support type, including carrier, active group parting, the active component
The quality of gold is the 0.1-5% of carrier quality；
The carrying method of the active group parting are as follows: with NaBH4As reducing agent, using PVA as protective agent, in room temperature
Under, restore HAuCl4Solution, with molar ratio computing, NaBH4/Au/PVA=2/1/0.5 obtains aurosol, is placed at room temperature for 0.5-10
After hour, aurosol is supported on carrier under stirring conditions, after filtration washing, vacuum drying, in 250-500 DEG C of air
Under the conditions of roast 4-8 hours, obtain load type nano gold catalyst, golden load capacity is the 0.1%-5% of carrier gross mass；Institute
Stating carrier is titanium oxide or titanium oxide；It is preferred that titanium dioxide carrier；HAuCl4The concentration of solution is 0.1-2mol/L.
The carrier is pre-processed through following methods are modified as a preferred technical solution: equi-volume impregnating to carrier into
Row is modified, and impregnated element is selected from least one of alkali metal or alkaline earth oxide, and load capacity is carrier gross mass
0.01%~5%.
The alkali or alkaline earth metal oxide is in K, Ca, Na, Mg, La, Zn as a preferred technical solution,
It is one or more kinds of.It is preferred that K, Mg, Ca, La；Nitrate (0.1-2mol/L) preferably by alkali metal or alkaline-earth metal is molten
Liquid is modified alumina support by equi-volume impregnating, obtains a series of alkali metal or alkaline earth oxide changes
The aluminium oxide or titanium dioxide carrier of property: Na/Al2O3 (TiO2), Mg/Al2O3(TiO2), K/Al2O3(TiO2), Ca/Al2O3
(TiO2),La/Al2O3(TiO2), Zn/Al2O3(TiO2).Na, Mg, Ca, La content distinguish preferred 0.01-1%, 0.01-1%,
0.01-1%, 0.5%-5%.
The present invention also provides application of the above-mentioned Au catalyst in catalytic oxidative dehydrogenation hexamethylene cyclohexene.
As a preferred technical solution, under the action of the load type gold catalyst, using air as oxidant, it is catalyzed oxygen
Fluidized dehydrogenation hexamethylene cyclohexene, 300-500 DEG C of reaction temperature.It is preferred that Au catalyst is to urge using hexamethylene as reaction raw materials
Agent, fixed bed is as reactor, within the temperature range of 300-600 DEG C, is passed through air or oxygen carries out oxidation reaction.
The Au catalyst preparation process that the present invention uses is simple, repeats, and has very high oxidative dehydrogenation of cyclonexane living
Property (be greater than 50%) and very high cyclohexene selectivity (greater than 50%).Catalyst has extraordinary stability simultaneously, can be with
100h or more is used continuously, and activity is not substantially reduced.
Detailed description of the invention
1 width of attached drawing of the present invention；
Fig. 1 Au/Ca/Al of the present invention2O3Gold catalyst catalyzing stability experiment
Specific embodiment
Below by specific embodiment, the present invention is described in detail, but these embodiments are not to the contents of the present invention
It is construed as limiting.
The preparation of 1 carrier of embodiment
Using alkali metal or nitrate (0.1-2mol/L) solution of alkaline-earth metal, by equi-volume impregnating to oxidation
Alumina supporter is modified, and obtains the aluminium oxide or titanium dioxide carrier that a series of alkali metal or alkaline earth oxide are modified: Na/
Al2O3(TiO2), Mg/Al2O3(TiO2), K/Al2O3(TiO2), Ca/Al2O3 (TiO2), La/Al2O3(TiO2), Zn/Al2O3
(TiO2), etc., in catalyst the load capacity of auxiliary agent be 0.01%~5%.
2 catalyst preparation of embodiment
At room temperature, chlorauric acid solution (0.05mol/L) (NaBH4/Au=of PVA protection is quickly restored by NaBH4
2/1), with molar ratio computing, NaBH4/Au/PVA=2/1/0.5 prepares partial size and obtains the nano Au particle of 2.0nm or so, then
Gold colloid is supported on modified aluminium oxide or titanium dioxide carrier under stirring conditions, after filtration washing, vacuum drying 12
Hour.It is roasted 4 hours under 350 degree of air conditions, removes ligand.Obtain a series of different nano catalyst of load capacity.
The load capacity of gold is 0.1%-5%.
Embodiment 3
Catalyzed conversion experiment: cyclohexane oxidation experiment carries out in the stainless steel tube reactor that internal diameter is 6mm, and catalyst is
The Au catalyst of the modified alumina load of sodium, loadings 1ml, hexamethylene flow are 0.05ml/min, and air velocity is
60ml/min, reaction temperature are 500 DEG C.Hexamethylene is after the preheating furnace of 180 degree is preheated by reactor before reacting.Instead
Should product quantification and qualification (table 1) be carried out using gas-chromatography afterwards.
Embodiment 4
Catalyzed conversion experiment: cyclohexane oxidation experiment carries out in the stainless steel tube reactor that internal diameter is 6mm, and catalyst is
Magnesium-modified titania oxide supported Au catalyst, loadings 1ml, hexamethylene flow are 0.05ml/min, and air velocity is
60ml/min, reaction temperature are 500 DEG C.Hexamethylene is after the preheating furnace of 180 degree is preheated by reactor before reacting.Instead
Should product quantification and qualification (table 2) be carried out using gas-chromatography afterwards.
Embodiment 5
Catalyzed conversion experiment: cyclohexane oxidation experiment carries out in the stainless steel tube reactor that internal diameter is 6mm, and catalyst is
The Au catalyst of the modified alumina load of calcium, loadings 1ml, hexamethylene flow are 0.05ml/min, and air velocity is
60ml/min, reaction temperature are 500 DEG C.Hexamethylene is after the preheating furnace of 180 degree is preheated by reactor before reacting.Instead
Should product quantification and qualification (table 3) be carried out using gas-chromatography afterwards.
Embodiment 6
Catalyzed conversion experiment: cyclohexane oxidation experiment carries out in the stainless steel tube reactor that internal diameter is 6mm, and catalyst is
The modified titania oxide supported Au catalyst of lanthanum, loadings 1ml, hexamethylene flow are 0.05ml/min, and air velocity is
60ml/min, reaction temperature are 500 DEG C.Hexamethylene is after the preheating furnace of 180 degree is preheated by reactor before reacting.Instead
Should product quantification and qualification (table 4) be carried out using gas-chromatography afterwards.
Embodiment 7
Catalyst stability experiment: cyclohexane oxidation experiment carries out in the stainless steel tube reactor that internal diameter is 6mm, is catalyzed
Agent is the Au catalyst of the modified alumina load of calcium, and loadings 1ml, hexamethylene flow is 0.05ml/min, air stream
Speed is 60ml/min, and reaction temperature is 500 DEG C.Hexamethylene is after 180 degree of preheating furnace is preheated by reaction before reacting
Device.Product quantification and qualification the result is shown in Figure 1 is carried out using gas-chromatography after reaction.
1 Au/Na/Al of table2O3Catalytic oxidation of cyclohexane cyclohexene
| Catalyst | Cyclohexane conversion % | Cyclohexene selectivity % | Other % |
| 1%Au/0.1%Na/Al2O3 | 45 | 50 | 50 |
| 1%Au/0.5%Na/Al2O3 | 40 | 55 | 45 |
| 1%Au/1%Na/Al2O3 | 37 | 61 | 39 |
| 1%Au/1.5%Na/Al2O3 | 30 | 60 | 40 |
2 Au/Mg/TiO of table2Catalytic oxidation of cyclohexane cyclohexene
| Catalyst | Cyclohexane conversion % | Cyclohexene selectivity % | Other % |
| 1%Au/0.1%Mg/TiO2 | 47 | 51 | 49 |
| 1%Au/0.5%Mg/TiO2 | 42 | 60 | 40 |
| 1%Au/1%Mg/TiO2 | 31 | 63 | 37 |
| 1%Au/1.5%Mg/TiO2 | 20 | 67 | 33 |
3 Au/Ca/Al of table2O3Catalytic oxidation of cyclohexane prepares cyclohexene
| Catalyst | Cyclohexane conversion % | Cyclohexene selectivity % | Other % |
| 1%Au/0.1%Ca/Al2O3 | 55 | 47 | 53 |
| 1%Au/0.5%Ca/Al2O3 | 50 | 53 | 47 |
| 1%Au/1%Ca/Al2O3 | 41 | 55 | 45 |
| 1%Au/1.5%Ca/Al2O3 | 22 | 51 | 49 |
4 Au/La/TiO of table2Catalytic oxidation of cyclohexane cyclohexene
| Catalyst | Cyclohexane conversion % | Cyclohexene selectivity % | Other % |
| 1%Au/0.1%La/TiO2 | 56 | 47 | 53 |
| 1%Au/0.5%La/TiO2 | 50 | 51 | 49 |
| 1%Au/1%La/TiO2 | 43 | 55 | 45 |
| 1%Au/1.5%La/TiO2 | 30 | 50 | 50 |
Claims (5)
1. a kind of Au catalyst, the Au catalyst is support type, including carrier, active group parting, the active group parting
Quality is the 0.1-5% of carrier quality；
The carrying method of the active group parting are as follows: with NaBH4As reducing agent, using PVA as protective agent, at room temperature, reduction
HAuCl4Solution, with molar ratio computing, NaBH4/Au/PVA=2/1/0.5 obtains aurosol, after being placed at room temperature for 0.5-10 hours,
Aurosol is supported on carrier under stirring conditions, after filtration washing, vacuum drying, under 250-500 DEG C of air conditions
Roasting 4-8 hours, obtains load type nano gold catalyst, and golden load capacity is the 0.1%-5% of carrier gross mass；
The carrier is titanium oxide or titanium oxide；
HAuCl4The concentration of solution is 0.1-2mol/L.
2. the load type gold catalyst according to claims, it is characterised in that: the carrier is modified pre- through following methods
Processing: equi-volume impregnating is modified carrier, impregnated element in alkali metal or alkaline earth oxide at least
One kind, load capacity are the 0.01%~5% of carrier gross mass.
3. load type gold catalyst according to claim 2, the alkali or alkaline earth metal oxide is K, Ca, Na,
One or more of Mg, La, Zn.
4. application of the Au catalyst described in claim 1-3 any one in catalytic oxidative dehydrogenation hexamethylene cyclohexene.
5. application according to claim 4, it is characterised in that: under the action of the load type gold catalyst, with air
For oxidant, catalytic oxidative dehydrogenation hexamethylene cyclohexene, 300-500 DEG C of reaction temperature.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112742367A (en) * | 2019-10-29 | 2021-05-04 | 中国石油化工股份有限公司 | Method for catalytic oxidation of cycloalkane |
| CN115254105A (en) * | 2022-08-10 | 2022-11-01 | 郑州大学 | Catalyst for preparing cyclohexene by cyclohexane dehydrogenation and preparation method and use method thereof |
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Application publication date: 20190528 |