CN107159260A - A kind of reduction of ethylene glycol prepares the preparation method and application of oxalic acid ester catalyst - Google Patents
A kind of reduction of ethylene glycol prepares the preparation method and application of oxalic acid ester catalyst Download PDFInfo
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- CN107159260A CN107159260A CN201710361696.4A CN201710361696A CN107159260A CN 107159260 A CN107159260 A CN 107159260A CN 201710361696 A CN201710361696 A CN 201710361696A CN 107159260 A CN107159260 A CN 107159260A
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- acid ester
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- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
- B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
- B01J23/89—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with noble metals
- B01J23/8926—Copper and noble metals
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
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- C07C67/36—Preparation of carboxylic acid esters by reaction with carbon monoxide or formates
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Abstract
The present invention provides the preparation method that a kind of reduction of ethylene glycol prepares oxalic acid ester catalyst, belongs to oxalate catalyst technical field.Including the presoma dissolving of the presoma of palladium and auxiliary agent 1) is made into maceration extract in an acidic solution;2) by α Al2O3Carrier add step 1) prepared by maceration extract in, after immersion dry;3) ethylene glycol and water are mixed to get reducing solution;4) by step 2) α Al after drying process2O3Carrier is added to step 3) in the reducing solution prepared, and soak;5) step 4) processing after α Al2O3Carrier is scrubbed successively, dry after produce oxalic acid ester catalyst of the present invention.The present invention prepares oxalic acid ester catalyst using reduction of ethylene glycol method, it is not necessary to hightemperature gas-phase reduction, reduces the preparation cost of catalyst.Catalyst Pd load capacity prepared by preparation method of the present invention is low, and metal dispersity is high, and catalytic reaction activity is high, is applied in carbon monoxide synthesis of oxalate, can effectively improve the conversion ratio of carbon monoxide and the selectivity of oxalate and space-time yield.
Description
Technical field
The invention belongs to oxalate catalyst technical field, specially a kind of reduction of ethylene glycol prepares oxalic acid ester catalyst
Preparation method and application.
Background technology
Oxalate is a kind of important industrial chemicals, is widely used in the chemicals such as synthesis medicine, dyestuff, extractant.Oxalic acid
Ester low-voltage hydrogenation can synthesize important industrial chemicals ethylene glycol, and oxalic acid can be made in ordinary-pressure hydrolysis, and normal pressure ammonolysis can obtain high-quality chemical fertilizer
Oxamides.
The technique of industrial production oxalate is mainly CO gas phase coupling methods at present, in recent years, reports successively both at home and abroad
The new development of CO gas phase coupling catalyst for synthesizing oxalic ester.More with Metal Palladium (Pd) for activearm in the catalyst reported at present
Point, α-Al2O3For carrier, and with SiO2It is that carrier all shows poor catalytic performance with activated carbon.Pd/α-Al2O3Catalyst
Apply the space-time yield in oxalate high, and possess preferable stability, its final activation step is all used in fixed bed reaction
The method of reducibility gas high temperature reduction is passed through in pipe.But Pd contents are still higher on catalyst (being industrially up to 2%), because
The direction of this CO coupling catalyst for synthesizing oxalic ester researchs is the Pd on reduction catalyst on the basis of catalyst performance is kept
Load capacity.Researcher has carried out substantial amounts of research, it is intended to reduce catalyst by adding auxiliary agent or improving preparation method
Pd load capacity, but the Pd contents in catalyst are still 1% or so.Also scholar's proposition can be by adding auxiliary agent or control
The method of catalyst coating Pd active component thickness processed, but it is all comparatively laborious, and cost is also of a relatively high, is unfavorable for industrialized life
Production.
The content of the invention
It is an object of the invention to for this present situation that existing oxalic acid ester catalyst Pd contents are high, catalyst cost is high,
There is provided that a kind of catalyst performance is good, Pd contents are low and the preparation method of the simple easily oxalic acid ester catalyst of shape.Oxalate of the present invention
Catalyst is prepared using reduction of ethylene glycol method, and the catalyst that the present invention is prepared is applied to carbon monoxide synthesis of oxalate.This hair
Improving eyesight is achieved through the following technical solutions:
An object of the present invention is to provide the preparation method that a kind of reduction of ethylene glycol prepares oxalic acid ester catalyst, including
Following steps:
1) maceration extract is made in the presoma dissolving of the presoma of palladium and auxiliary agent in an acidic solution;The presoma of palladium such as nitre
PH value of solution < 7 is in acidity when sour palladium, palladium bichloride are dissolved in water, and palladium is water insoluble but can be dissolved in acetic acid, the solution of formation
Also in acidity;
2) by α-Al2O3Carrier add step 1) prepared by maceration extract in, after immersion dry;
3) ethylene glycol and water are mixed to get reducing solution;
4) by step 2) α-Al after drying process2O3Carrier is added to step 3) in the reducing solution prepared, and soak;
5) step 4) processing after α-Al2O3Carrier is scrubbed successively, dry after produce oxalic acid ester catalyst of the present invention.
The present invention is that reducing agent prepares oxalic acid ester catalyst by reducing agent alcohol of ethylene glycol, and reaction condition is gentle, operation letter
Single, obtained grain diameter is small and is evenly distributed.The mechanism of alcohols reduction palladium salt can be represented with below equation:
Pd2++RCH2OH→Pd+RCHO+2H+
A specific implementation of the preparation method of oxalic acid ester catalyst is prepared according to a kind of reduction of ethylene glycol of the present invention
Example, the presoma of the palladium is one or more in palladium bichloride, palladium nitrate, palladium or palladium acetylacetonate, and final gained is catalyzed
The content of palladium is calculated as the 0.05~1.0% of vehicle weight with palladium element in agent.
A specific implementation of the preparation method of oxalic acid ester catalyst is prepared according to a kind of reduction of ethylene glycol of the present invention
Example, it is characterised in that the precursor of the auxiliary agent is selected from group VIII, group of the lanthanides, IB, the oxide of Group IIB transition metal
Or salt, finally the content of auxiliary agent is calculated as the 0.01~1% of vehicle weight with element in gained catalyst.
A specific implementation of the preparation method of oxalic acid ester catalyst is prepared according to a kind of reduction of ethylene glycol of the present invention
Example, step 1) in, the acid solution is hydrochloric acid solution or salpeter solution, and the pH of the acid solution is 0~6;The dipping
The concentration of palladium ion is 0.005~0.06mol/L in liquid.
A specific implementation of the preparation method of oxalic acid ester catalyst is prepared according to a kind of reduction of ethylene glycol of the present invention
Example, step 2) in, the α-Al2O3Carrier is one kind or several in column, sphere or the Raschig ring shape thing of compression molding
Kind;The soaking temperature is 40~60 DEG C, and the time is 6~24h;The drying temperature is 90~200 DEG C, and the time is 12~24h.
A specific implementation of the preparation method of oxalic acid ester catalyst is prepared according to a kind of reduction of ethylene glycol of the present invention
Example, step 3) in, the volume ratio of the glycol and water is 0.5~5;The reducing solution is the aqueous solution of ethylene glycol.
A specific implementation of the preparation method of oxalic acid ester catalyst is prepared according to a kind of reduction of ethylene glycol of the present invention
Example, step 4) in, the soaking temperature is 40~60 DEG C, and the time is 12~24h;Step 5) in, the drying temperature be 90~
200 DEG C, the time is 12~24h.
The second object of the present invention is to provide a kind of catalyst of carbon monoxide synthesis of oxalate, the catalyst use
Above-mentioned preparation method is prepared.
The third object of the present invention is to provide a kind of application of the catalyst of carbon monoxide synthesis of oxalate, the catalysis
Application of the agent in carbon monoxide and nitrous acid ester preparing oxalate coupling reaction.
According to an a kind of specific embodiment of the application of the catalyst of carbon monoxide synthesis of oxalate of the present invention, institute
The mol ratio for stating carbon monoxide and nitrous acid ester is 1.2~1.6, and it is 110~140 DEG C to catalyze and synthesize temperature, when catalyst is contacted
Between be 1~3s.
Compared with prior art, the invention has the advantages that:
1st, the present invention prepares oxalic acid ester catalyst using reduction of ethylene glycol method, it is not necessary to hightemperature gas-phase reduction, reduces and urges
The preparation cost of agent.
2nd, the catalyst Pd load capacity that prepared by preparation method of the present invention is low, but reactivity is high, is applied to an oxidation
Carbon and nitrous acid ester coupling synthesis of oxalate in, can effectively improve carbon monoxide conversion ratio and oxalate selectivity and
Space-time yield.
3rd, catalyst metals decentralization prepared by preparation method of the present invention is high, can be loaded in lower temperature and low noble metal
The lower efficient catalytic CO vapor phase carbonylation synthesis of oxalate of amount.
Embodiment
In order to make the purpose , technical scheme and advantage of the present invention be clearer, with reference to embodiments, to the present invention
It is further elaborated.It should be appreciated that the specific embodiments described herein are merely illustrative of the present invention, it is not used to
Limit the present invention.
Embodiment 1
The preparation of the present embodiment oxalic acid ester catalyst is carried out according to the method for the invention, specific preparation process is as follows:
1) 0.325g palladium nitrates and 0.073g auxiliary agent copper nitrates are dissolved in the salpeter solution that pH is 1.0, gained dipping
Liquid product is 40mL;
2) by column α-Al2O3Carrier is added such as step 1) obtained by maceration extract in, and soak 12h at 60 DEG C, then
It is put into baking oven at 110 DEG C and dries 12h;
3) by ethylene glycol and distilled water with volume ratio VEthylene glycol/VWater=3 ratio is mixed to get reducing solution;
4) by step 2) processing after α-Al2O3Carrier is added to step 3) prepare reducing solution in, at 50 DEG C soak
18h
5) by step 4) processing after α-Al2O3Carrier is put into baking oven and dried at 100 DEG C with water washing is distilled 3~5 times
The content that 24h produces Pd in the present embodiment oxalate finished catalyst A3, the catalyst is the 0.3% of vehicle weight, auxiliary agent Cu
Content be vehicle weight 0.05%.
Embodiment 2
By the step 4 of embodiment 1) in ethylene glycol and distilled water volume ratio VEthylene glycol/VWaterIt is changed into 0.5,1,5 respectively, produces reality
Apply finished catalyst A1, A2, A4 in example 2.
Embodiment 3
The present embodiment is comparative example, by the step 4 of embodiment 1) in ethylene glycol and distilled water volume ratio VEthylene glycol/VWaterBecome respectively
For 0 (ethylene glycol addition is 0), 7, finished catalyst B1, B2 in comparative example 1 are produced.
Embodiment 4
The present embodiment is comparative example, and the preparation of oxalic acid ester catalyst, specific system are carried out according to the preparation method of tradition dipping
Standby step is as follows:
1) 0.325g palladium nitrates and 0.073g auxiliary agent copper nitrates are dissolved in the salpeter solution that pH is 1.0, gained leaching
Stain liquid product is 40mL;
2) by column α-Al2O3Carrier is added such as step 1) obtained by maceration extract in, then at 60 DEG C soak 12h;
3) will be through step 2) processing after α-Al2O3Carrier is put into baking oven and 12h is dried at 110 DEG C, and in 300 DEG C of conditions
Lower roasting 12h;
4) will be through step 3) processing after α-Al2O3Carrier is in H2Reduced 4 hours under atmosphere, wherein reducing gas temperature is
300 DEG C, air speed is 2000h-1, room temperature is then down under reducing atmosphere, produces the present embodiment finished catalyst B3, the catalyst
Middle Pd content is the 0.3% of vehicle weight, and auxiliary agent Cu content is the 0.05% of vehicle weight.
Embodiment 5
In order to verify the prepared catalyst of above-described embodiment 1~3 to CO conversion ratios, oxalate selectivity and space-time yield etc.
The influence of correlated performance, is utilized respectively catalyst A1~A4, B1~B3 and carries out carbon monoxide and nitrous ether (ethyl nitrite) synthesis of oxalic acid two
Ethyl ester, specific synthesis and reaction process are as follows:
The present embodiment uses atmospheric fixed bed reactor, wherein, reactor inside diameter is 20mm, the built-in thermocouple set of reactor
Pipe, catalyst amount is 10mL, and unstripped gas passes through beds, is collected after product diethy-aceto oxalate is condensed.
The mol ratio of reaction gas carbon monoxide and nitrous ether (ethyl nitrite) is 1.3, and carrier gas is nitrogen, and catalysts bed temperature is 110
DEG C, catalyst contact time is 3s.Catalyst A1~A4, B1~B3 carries out the performance test of synthesizing diethyl oxalate with carbon monoxide
As a result it is as shown in table 1 below:
The catalyst A1 of table 1~A4, B1~B3 carries out the performance test results of synthesizing diethyl oxalate with carbon monoxide
As can be seen from Table 1, the A1~A4 prepared using the inventive method and B1, B2 catalyst performance result shown,
The volume ratio V of ethylene glycol and distilled waterEthylene glycol/VWaterThe catalyst prepared when between 0.5~5 shows good catalytic
Energy.Catalyst A1~the A4 prepared using the inventive method can be significantly improved compared with catalyst B3 prepared by tradition dipping
The conversion ratio of carbon monoxide and nitrous ether (ethyl nitrite), and catalyst A1~A4 catalyst diethy-aceto oxalate selectivity (i.e. in product
Diethy-aceto oxalate content) more than 90% can be reached, and catalyst B3 ethyl oxalate selectively only has 84% or so, meanwhile,
Catalyst A1~A4 has more preferable diethy-aceto oxalate space-time yield compared to catalyst B3.Tested by above catalyst performance
Result data shows that the catalyst A1 that the present invention is prepared by reduction of ethylene glycol~A4 tradition impregnates the catalyst B3 phases prepared
Than showing higher CO conversion, diethy-aceto oxalate selectivity and space-time yield in identical Pd load capacity.
The foregoing is merely illustrative of the preferred embodiments of the present invention, is not intended to limit the invention, all essences in the present invention
Any modifications, equivalent substitutions and improvements made within refreshing and principle etc., should be included in the scope of the protection.
Claims (10)
1. a kind of reduction of ethylene glycol prepares the preparation method of oxalic acid ester catalyst, it is characterised in that comprise the following steps:
1) maceration extract is made in the presoma dissolving of the presoma of palladium and auxiliary agent in an acidic solution;
2) by α-Al2O3Carrier add step 1) prepared by maceration extract in, after immersion dry;
3) ethylene glycol and water are mixed to get reducing solution;
4) by step 2) α-Al after drying process2O3Carrier is added to step 3) in the reducing solution prepared, and soak;
5) step 4) processing after α-Al2O3Carrier is scrubbed successively, dry after produce oxalic acid ester catalyst of the present invention.
2. a kind of reduction of ethylene glycol as claimed in claim 1 prepares the preparation method of oxalic acid ester catalyst, it is characterised in that described
The presoma of palladium is one or more in palladium bichloride, palladium nitrate, palladium, and the content of palladium is with palladium element in final gained catalyst
It is calculated as the 0.05~1.0% of vehicle weight.
3. a kind of reduction of ethylene glycol as claimed in claim 1 prepares the preparation method of oxalic acid ester catalyst, it is characterised in that described
The precursor of auxiliary agent is selected from group VIII, group of the lanthanides, IB, the oxide or salt of Group IIB transition metal, and final gained is catalyzed
The content of auxiliary agent is calculated as the 0.01~1% of vehicle weight with element in agent.
4. a kind of reduction of ethylene glycol as claimed in claim 1 prepares the preparation method of oxalic acid ester catalyst, it is characterised in that step
1) in, the acid solution is hydrochloric acid solution or salpeter solution, and the pH of the acid solution is 0~6;In the maceration extract palladium from
The concentration of son is 0.005~0.06mol/L.
5. a kind of reduction of ethylene glycol as claimed in claim 1 prepares the preparation method of oxalic acid ester catalyst, it is characterised in that step
2) in, the α-Al2O3Carrier is the one or more in column, sphere or the Raschig ring shape thing of compression molding;The leaching
It is 40~60 DEG C to steep temperature, and the time is 6~24h;The drying temperature is 90~200 DEG C, and the time is 12~24h.
6. a kind of reduction of ethylene glycol as claimed in claim 1 prepares the preparation method of oxalic acid ester catalyst, it is characterised in that step
3) in, the volume ratio of the glycol and water is 0.5~5;The reducing solution is the aqueous solution of ethylene glycol.
7. a kind of reduction of ethylene glycol as claimed in claim 1 prepares the preparation method of oxalic acid ester catalyst, it is characterised in that step
4) in, the soaking temperature is 40~60 DEG C, and the time is 12~24h;Step 5) in, the drying temperature is 90~200 DEG C, when
Between be 12~24h.
8. a kind of catalyst of carbon monoxide synthesis of oxalate, it is characterised in that the catalyst uses claim 1 to 7 institute
The preparation method stated is prepared.
9. a kind of application of the catalyst of carbon monoxide synthesis of oxalate as claimed in claim 8, it is characterised in that the catalysis
Application of the agent in carbon monoxide and nitrous acid ester preparing oxalate coupling reaction.
10. a kind of application of the catalyst of carbon monoxide synthesis of oxalate as claimed in claim 9, it is characterised in that described one
The mol ratio of carbonoxide and nitrous acid ester is 1.2~1.6, catalyzes and synthesizes temperature for 110~140 DEG C, catalyst contact time is 1
~3s.
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Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
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CN108201897A (en) * | 2018-02-01 | 2018-06-26 | 黑龙江省科学院石油化学研究院 | The method that ultrasonic wave added local reduction way prepares SBA-15 loaded nanometer palladium catalysts |
CN108816246A (en) * | 2018-04-18 | 2018-11-16 | 东风商用车有限公司 | High-dispersion anti-sintering diesel vehicle ASC catalyst and preparation method thereof |
Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
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CN105597743A (en) * | 2016-03-01 | 2016-05-25 | 中国科学院福建物质结构研究所 | Preparation method of catalyst for CO gas-phase catalyzed synthesis of dimethyl oxalate |
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2017
- 2017-05-22 CN CN201710361696.4A patent/CN107159260A/en active Pending
Patent Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
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CN105597743A (en) * | 2016-03-01 | 2016-05-25 | 中国科学院福建物质结构研究所 | Preparation method of catalyst for CO gas-phase catalyzed synthesis of dimethyl oxalate |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN108201897A (en) * | 2018-02-01 | 2018-06-26 | 黑龙江省科学院石油化学研究院 | The method that ultrasonic wave added local reduction way prepares SBA-15 loaded nanometer palladium catalysts |
CN108816246A (en) * | 2018-04-18 | 2018-11-16 | 东风商用车有限公司 | High-dispersion anti-sintering diesel vehicle ASC catalyst and preparation method thereof |
CN108816246B (en) * | 2018-04-18 | 2020-05-08 | 东风商用车有限公司 | High-dispersion anti-sintering diesel vehicle ASC catalyst and preparation method thereof |
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Application publication date: 20170915 |