A kind of catalyst for alkynol selective hydrogenation and its preparation method and application
Technical field
The invention belongs to organic synthesis field is and in particular to a kind of be used for c5-c20Chain alkynol selective hydration is c5-c20
Catalyst of alkenols and preparation method and application.
Background technology
Alkynol is selectively hydrogenated to the important process that enol is in fine chemistry industry, such as during the chemosynthesis of vitamin e
It is related to the synthesis of several important intermediate, such as linalool, nerolidol, different vegetable alcohol etc., the synthesis of these intermediate is all used
To selective hydrocatalyst.Palladium metal shows good activity and selectivity in alkynol selective hydrogenation process.
The catalyst that industrial alkynol enol process is mainly applied at present is Lin Dela (lindlar) catalyst, and this is urged
Agent with Calcium Carbonate or barium sulfate as carrier, carried metal pd, be simultaneously introduced metal pb and play poisoning effect, to improve catalyst
Selectivity.Patent cn 104394988a discloses a kind of preparation method of new lindlar catalyst, and this catalyst is main
It is to improve selectivity of catalyst by controlling the particle diameter (more than 10um) of calcium carbonate carrier.But it is as getting over of environmental legislation
Come stricter, the process of pb metal in decaying catalyst has very hang-up, and heel rate is higher.Patent cn1151725a is public
Open a kind of method of selective hydrogenation of butine diol to butene diol, this catalyst carrier is mainly with δ-aluminium oxide for carrying
Body, pd and zn or cu or ag, with certain proportion dip loading, obtains catalyst after reduction, this catalyst avoids adding of metal pb
Enter, and the selectivity of butynediols is high low with by-products content.Patent cn103406121a discloses a kind of charcoal and carries Palladium monoxide
Catalyst and its preparation method and application, this catalyst, with activated carbon as carrier, forms hydration oxygen by adjusting ph value with alkali liquor
Change palladium colloid solution, impregnation process for a period of time after, then with alkali liquor adjust impregnation liquid ph value, continuation time of infusion
Afterwards, filtration washing, to neutral, obtain charcoal and carries palladium oxide catalyst, this catalyst is anti-in Isosorbide-5-Nitrae-butynediols Isosorbide-5-Nitrae-butylene glycol
Show higher selectivity (99%) in answering, and palladium metal easily recycles.Both the above catalyst is primarily directed to
Specific alkynol reactant, therefore has certain limitation in application.
Patent cn101616733a discloses a kind of Structured catalysts, with metallic fiber smf as carrier, first loads zno,
Impregnate palladium nano-particles again, this catalyst has higher selectivity (95%), but preparation technology is more complicated, and catalyst holds
Easy in inactivation is although fresh catalyst level can be substantially returned to by catalyst activity by way of regeneration, but is used for kettle
Formula reaction in and be unfavorable for operate.
In sum, the active component of alkynol selective hydrocatalyst is mainly metal pd, and carrier can select activity
Charcoal, aluminium sesquioxide, metal gauze, Calcium Carbonate, barium sulfate, silicon dioxide etc., inhibitor is mainly from pb, ag, bi, mn, zn, cu
Select Deng in metal.The improving of catalyst is mainly and changes the enol and alkanol speed in catalyst surface adsorption desorption so that alkynes
The enol that alcohol is hydrogenated to quickly can leave catalyst surface, rather than continues to be hydrogenated to alkanol.At present in publication
Catalyst has plenty of effective for a kind of specific alkynol, has plenty of and there is metal recovery, there is presently no one kind
Can be suitable for different carbon chain lengths alkynol selective hydrocatalyst, and the metal being capable of in catalyst is easily recycled
Simultaneously environmentally friendly.
Content of the invention
It is an object of the invention to provide a kind of catalyst for alkynol selective hydrogenation and its preparation method and application, should
Catalyst does not contain pb, in c5-c20Show in chain alkynol selective hydrogenation process excellent activity (conversion ratio reach 99.5% with
On) and selectivity, and time use can be realized, the pd metal in catalyst easily reclaims.
A kind of catalyst for alkynol selective hydrogenation, including carrier and active component, described active component includes
The alloy phase that pd and pd-zn is formed, the zno that described carrier coats for N doping Carbon Materials.
The catalyst of the present invention do not contain metal pb, decrease the pollution to environment in catalyst recovery process, simultaneously
There is higher conversion ratio and selectivity;And be conducive to the recovery of pd metal for carrier with the zno of N doping Carbon Materials cladding
Using.
Preferably, also containing suppression composition x in described active component, described x is selected from one of bi, mn, ag.
Now, this catalyst has the structure that following chemical formula represents: pdx/cn@zno.
As further preferred, mol ratio pd:x=10:1-30:0 of active component pd and x, pd and N doping raw material of wood-charcoal
The mass ratio of the zno carrier of material cladding is 0.1%-5%, and pd herein includes pd present in single-phase pd and alloy phase.
Preferably, the mass ratio of n:c:zno is 1:6:7-3:1 in the zno carrier of described N doping Carbon Materials cladding:
15.
In described catalyst, the particle diameter of described carrier is 150-250 mesh, and the particle diameter of pd is 2-20nm, catalyst
Specific surface area 10-1000m2/g.
The concrete preparation process of above-mentioned catalyst is as follows:
(1) aqueous solution in nitrogenous charcoal source and zno powder are stirred at 150-200 DEG C, moisture is evaporated, the mixing obtaining
Solid under nitrogen protection, is calcined under the conditions of 400-600 DEG C, obtains the zno carrier of N doping Carbon Materials cladding;
(2) by palladium source, stabilizer and inhibitor (wherein it is desired to during suppression composition, add inhibitor, otherwise, be not required to herein
Inhibitor to be added) it is dissolved in the water, stirring, it is heated to 90-120 DEG C and constant temperature 1-3h, be down to logical hydrogen reducing after room temperature
0.5-1h, obtains palladium colloidal sol;
(3) carrier impregnation obtaining step (1) 2-24h in the palladium colloidal sol that step (2) obtains, then at 60-120 DEG C
Lower drying, obtains catalyst crude product;
(4) the catalyst crude product obtaining step (3) is placed in stove, with 10-30 DEG C per minute be warming up to 300-600 DEG C,
Then reduce 1-3h under hydrogen atmosphere, obtain catalyst;
Described nitrogenous charcoal source is glucosamine hydrochloride, glucosamine sulphate, tripolycyanamide, carbamide and bamboo
One of.
Described palladium source is pdcl2, pd (no3)2, na2pdcl4, pd (ch3coo)2One of;
Described stabilizer is pvp, pva, sodium citrate, one of ammonium molybdate;
Described inhibitor is bi (no3)3, mncl2, agno3One of;
The particle diameter of the catalyst carrier of the method preparation is 150-250 mesh, and the particle diameter of pd is 2-20nm, the ratio table of catalyst
Area 10-1000m2/g;Mainly mutually existed with pd-zn alloy with palladium simple substance, its tem electron microscope is shown in Fig. 1.
Present invention also offers the application in enol prepared by a kind of described catalyst in high selectivity hydrogenation of alkinols, by alkynes
Alcohol (formula i), solvent and described catalyst put in reactor, carry out selective hydrogenation under an atmosphere of hydrogen, and reaction is finished,
Cooling filtering catalyst, obtain corresponding enol (formula ii), course of reaction is as follows:
Wherein r represents alkyl (such as methyl butynol, dehydrogenation linalool, the dehydrogenation different vegetable alcohol that carbon number is 1-16
Deng), for different reactants, by controlling the preparation process of catalyst, the conversion ratio of catalyst, up to more than 99.5%, selects
Selecting property is more than 95%.
Wherein, described alkyl includes alkyl, alkenyl or alkynyl, preferably alkyl or alkenyl.
The solvent that described solvent is commonly used for this area hydrogenation reaction, those skilled in the art can be according to existing knowledge
Selected, generally polar solvent, such as alcoholic solvent and water etc..
The catalyst being filtrated to get can be applied mechanically, and result of the test shows after time, the activity of catalyst
No substantially reduce with selectivity.
Compared with the existing technology, this catalyst be mainly characterized by do not contain metal pb, decrease catalyst recovery process
In pollution to environment, and be conducive to the recycling of pd metal for carrier with the zno of N doping Carbon Materials cladding.Should simultaneously
Catalyst is in c5-c20Show high selectivity and high stability in the selective hydrogenation process of alkynol, advantageously reduce catalyst
Cost.
Brief description
Fig. 1 is the tem figure of catalyst a;
Fig. 2 catalyst a applies mechanically situation in methyl butynol hydrogenation reaction, and wherein vertical coordinate is reaction selectivity, horizontal
Coordinate is to apply mechanically number of times.
With reference to specific embodiment, the present invention is further illustrated.
Specific embodiment
Following examples are used for further illustrating the present invention, but the present invention is not limited only to these embodiments.
Embodiment 1
The preparation of catalyst: add 3g glucosamine hydrochloride, 25ml water stirring and dissolving in 50ml flask, add 2g
Zno powder, in oil bath pan 150 DEG C stir dry.Stir and be ground to powder after doing.Logical nitrogen calcining in tube furnace, 10 DEG C/min rises to
550 DEG C, constant temperature 2h, then ground uniformly, prepared cn@zno complex carrier, kept dry, wherein n:c:zno=1:6:10
(mass ratio).
0.05g pvp (Polyvinylpyrrolidone) dissolving, pvp and pdcl is added in 25ml water2Mol ratio be 10:1,
The mass percent concentration that Deca prepares in advance is 0.5%pdcl2Solution and 0.1%bi (no3)3Solution, pd and bi mole
Ratio for 10:1, is heated to 100 DEG C, keeps 3h.It is down to room temperature (20-25 DEG C) and leads to hydrogen 2 hours afterwards, be then washed with deionized
Obtain palladium colloidal sol 3 times, be then transferred in beaker, add the above-mentioned composite material carrier of 0.5g, 12h is stirred at room temperature, spends
Ion water washing 3 times, 60 DEG C are dried 12h.Lead to hydrogen reducing in tube furnace, 10 DEG C/min rises to 500 DEG C, keeps 3h, obtains
Catalyst a, obtains specific surface area of catalyst in 15g/m2, catalyst particle size 200-250 mesh, pd size is in 15-20nm.
Embodiment 2
The preparation of catalyst: add 3.0g bamboo powder, 25ml water stirring and dissolving in 50ml flask, add 1.5g zno,
In oil bath pan 150 DEG C stir dry.Stir and be ground to powder after doing, logical nitrogen calcining in tube furnace, 10 DEG C/min rises to 550 DEG C, keeps
2h, is then ground uniformly, prepared cn@zno complex carrier, kept dry, wherein n:c:zno=1:6:7 (mass ratio).
0.1g pvp dissolving, pvp and pdcl is added in 15ml water2Mol ratio be 20:1, Deca prepares in advance
0.5%pdcl2Solution and 0.1%bi (no3)3Solution, the mol ratio of pd and bi is 10:1, is heated to 105 DEG C, keeps 3h.It is down to
Room temperature (20-25 DEG C) leads to hydrogen 2 hours afterwards, and then deionized water wash obtains palladium colloidal sol 3 times, is then transferred to beaker
In, add the above-mentioned composite material carrier of 0.5g, 12h is stirred at room temperature, is washed with deionized 3 times, 120 DEG C are dried 12h.In tubular type
Hydrogen reducing is led to, 10 DEG C/min rises to 600 DEG C, keeps 3h, obtains catalyst b in stove.Obtain specific surface area of catalyst in 450g/
m2, catalyst particle size 150-200 mesh, pd size is in 15-20nm.
Embodiment 3
The preparation of catalyst: add 3.0g tripolycyanamide, 25ml water stirring and dissolving in 50ml flask, add 1.5g
Zno, in oil bath pan 170 DEG C stir dry.Stir and be ground to powder after doing, logical nitrogen calcining in tube furnace, 10 DEG C/min rises to 550
DEG C, keep 2h, then ground uniformly, prepared cn@zno complex carrier, kept dry.Wherein n:c:zno=2.5:1:7
(mass ratio).
0.1g pva (polyvinyl alcohol) dissolving, pva and pdcl is added in 10ml water2Mol ratio be 10:1, Deca is pre-
The 1.0%pdcl first preparing2Solution and 0.034%agno3Solution, the mol ratio of pd and ag is 30:1, is heated to 100 DEG C, protects
Hold 3h.It is down to room temperature (20-25 DEG C) and leads to hydrogen 2 hours afterwards, be then washed with deionized 3 times and obtain palladium colloidal sol, then by it
It is transferred in beaker, add the above-mentioned composite material carrier of 0.5g, 12h is stirred at room temperature, is washed with deionized 3 times, 120 DEG C of dryings
12h.Lead to hydrogen reducing in tube furnace, 10 DEG C/min rises to 400 DEG C, keeps 3h, obtains catalyst c.Obtain catalyst and compare table
Area is in 50g/m2, catalyst particle size 200-250 mesh, pd size is in 15-20nm.
Embodiment 4
The preparation of catalyst: add 3.0g carbamide, 25ml water stirring and dissolving in 50ml flask, add 1.5g zno,
In oil bath pan 170 DEG C stir dry.Stir and be ground to powder after doing, logical nitrogen calcining in tube furnace, 10 DEG C/min rises to 550 DEG C, keeps
2h, is then ground uniformly, prepared cn@zno complex carrier, kept dry, wherein n:c:zno=3:1:7 (mass ratio).
Add the dissolving of 0.03g ammonium molybdate in 10ml water, the mol ratio of mo and pd is 10:1, and Deca prepares in advance
2.0%pdcl2Solution, is heated to 100 DEG C, keeps 3h.It is down to room temperature (20-25 DEG C) and leads to hydrogen 2 hours afterwards, then use deionization
Water washing obtains palladium colloidal sol 3 times, is then transferred in beaker, adds the above-mentioned composite material carrier of 0.5g, is stirred at room temperature
12h, is washed with deionized 3 times, 120 DEG C are dried 12h.Lead to hydrogen reducing in tube furnace, 30 DEG C/min rises to 500 DEG C, protects
Hold 3h, obtain catalyst d.
Embodiment 5
The preparation of catalyst: add 3.0g glucosamine sulphate, 25ml water stirring and dissolving in 50ml flask, add
3.0g zno, in oil bath pan 150 DEG C stir dry.Stir and be ground to powder after doing, logical nitrogen calcining in tube furnace, 30 DEG C/min rises to
600 DEG C, keep 3h, then ground uniformly, prepared cn@zno complex carrier, kept dry, wherein n:c:zno=1:6:15
(mass ratio).
0.02g pva dissolving, pva and pdcl is added in 15ml water2Mol ratio be 5:1, Deca prepares in advance
0.2%na2pdcl4Solution and 0.02%bi (no3)3Solution, the mol ratio of pd and bi is 20:1, is heated to 110 DEG C, keeps 3h.
It is down to room temperature (20-25 DEG C) and leads to hydrogen 0.5 hour afterwards, be then washed with deionized 3 times and obtain palladium colloidal sol, then shifted
To beaker, add the above-mentioned composite material carrier of 0.5g, 12h is stirred at room temperature, is washed with deionized 3 times, 60 DEG C are dried 12h.
Lead to hydrogen reducing in tube furnace, 20 DEG C/min rises to 600 DEG C, keeps 3h, obtains catalyst e.
Obtain specific surface area of catalyst in 30g/m2, catalyst particle size 200-250 mesh, pd size is in 2-10nm.
Embodiment 6
The preparation of catalyst: add 3.0g glucosamine sulphate, 25ml water stirring and dissolving in 50ml flask, add
1.5g zno, in oil bath pan 150 DEG C stir dry.Stir and be ground to powder after doing, logical nitrogen calcining in tube furnace, 30 DEG C/min rises to
600 DEG C, keep 3h, then ground uniformly, prepared cn@zno complex carrier, kept dry, wherein n:c:zno=1:6:7
(mass ratio).
0.02g pvp dissolving, pvp and pdcl is added in 10ml water2Mol ratio be 10:1, Deca prepares in advance
0.2%na2pdcl4Solution, is heated to 120 DEG C, keeps 3h.It is down to room temperature (20-25 DEG C) and leads to hydrogen 0.5 hour afterwards, then spend
Ion water washing obtains palladium colloidal sol 3 times, is then transferred in beaker, adds the above-mentioned composite material carrier of 0.5g, and room temperature is stirred
Mix 12h, be washed with deionized 3 times, 120 DEG C are dried 12h.Lead to hydrogen reducing in tube furnace, 10 DEG C/min rises to 600 DEG C,
Keep 3h, obtain catalyst f.
Embodiment 7
The preparation of catalyst: add 3.0g glucosamine hydrochloride, 25ml water stirring and dissolving in 50ml flask, add
2.0g zno, in oil bath pan 150 DEG C stir dry.Stir and be ground to powder after doing, logical nitrogen calcining in tube furnace, 30 DEG C/min rises to
600 DEG C, keep 3h, then ground uniformly, prepared cn@zno complex carrier, kept dry, wherein n:c:zno=1:6:10
(mass ratio).
0.02g pvp dissolving, pvp and pdcl is added in 10ml water2Mol ratio be 5:1, Deca prepares in advance
0.1%na2pdcl4Solution and 0.01%bi (no3)3Solution, the mol ratio of pd and bi is 20:1, is heated to 120 DEG C, keeps 3h.
It is down to room temperature (20-25 DEG C) and leads to hydrogen 0.5 hour afterwards, be then washed with deionized 3 times and obtain palladium colloidal sol, then shifted
To beaker, add the above-mentioned composite material carrier of 0.5g, 12h is stirred at room temperature, is washed with deionized 3 times, 120 DEG C are dried 12h.
Lead to hydrogen reducing in tube furnace, 20 DEG C/min rises to 600 DEG C, keeps 3h, obtains catalyst g.Obtain specific surface area of catalyst
In 20g/m2, catalyst particle size 200-250 mesh, pd size is in 10-15nm.
Embodiment 8
The preparation of catalyst: add 3.0g glucosamine hydrochloride, 25ml water stirring and dissolving in 50ml flask, add
2.0g zno, in oil bath pan 180 DEG C stir dry.Stir and be ground to powder after doing, logical nitrogen calcining in tube furnace, 30 DEG C/min rises to
600 DEG C, keep 3h, then ground uniformly, prepared cn@zno complex carrier, kept dry, wherein n:c:zno=1:6:10
(mass ratio).
0.06g pvp dissolving, pvp and pdcl is added in 25ml water2Mol ratio be 5:1, Deca prepares in advance
0.3%pdcl2Solution and 0.01%mncl2Solution, the mol ratio of pd and mn is 15:1, is heated to 120 DEG C, keeps 3h.It is down to room
Warm (20-25 DEG C) leads to hydrogen 0.5h afterwards, is then washed with deionized 3 times and obtains palladium colloidal sol, is then transferred in beaker,
Add the above-mentioned composite material carrier of 0.5g, 12h is stirred at room temperature, is washed with deionized 3 times, 120 DEG C are dried 12h.In tube furnace
In logical hydrogen reducing, 20 DEG C/min rises to 600 DEG C, keeps 3h, obtain catalyst h.
Comparative catalyst
Embodiment 9 is by commercially available lindlar catalyst catalyst i as a comparison.
Embodiment 10
Add 3g glucosamine hydrochloride, 25ml water stirring and dissolving in 50ml flask, 150 DEG C are stirred in oil bath pan
Dry.Stir and be ground to powder after doing.Logical nitrogen calcining in tube furnace, 10 DEG C/min rises to 550 DEG C, and then constant temperature 2h is ground
Uniformly, prepared cn complex carrier, kept dry.Pvp dissolving, the 0.5%pdcl that Deca prepares in advance is added in 25ml water2
Solution, pvp and pdcl2Mol ratio be 10:1, be heated to 100 DEG C, keep 3h.Logical hydrogen 2 is little afterwards to be down to room temperature (20-25 DEG C)
When, reduced rear water washing 3 times, be then transferred in beaker, add the above-mentioned carrier of 0.5g, 12h is stirred at room temperature, spend from
Sub- water washing 3 times, 60 DEG C are dried 12h.Lead to hydrogen reducing in tube furnace, 10 DEG C/min rises to 500 DEG C, keeps 3h, it is right to obtain
Ratio catalyst j.
Embodiment 11
Pvp dissolving, the 0.5%pdcl that Deca prepares in advance is added in 25ml water2Solution, pvp and pdcl2Mole
Ratio for 10:1, is heated to 100 DEG C, keeps 3h.It is down to room temperature (20-25 DEG C) and leads to hydrogen 2 hours afterwards, reduced rear water washing 3 times,
It is then transferred in beaker, add 0.5g zno carrier, 12h is stirred at room temperature, is washed with deionized 3 times, 60 DEG C of dryings
12h.Lead to hydrogen reducing in tube furnace, 10 DEG C/min rises to 500 DEG C, keeps 3h, obtains comparative catalyst k.
Embodiment 12
Add 3g glucosamine hydrochloride, 25ml water stirring and dissolving in 50ml flask, 150 DEG C are stirred in oil bath pan
Dry.Stir and be ground to powder after doing.Logical nitrogen calcining in tube furnace, 10 DEG C/min rises to 550 DEG C, and then constant temperature 2h is ground
Uniformly, prepared cn carrier, kept dry.Pvp dissolving, the 0.5%pdcl that Deca prepares in advance is added in 25ml water2Solution
With 1% zn (no3)2, pvp and pdcl2Mol ratio be 10:1, be heated to 100 DEG C, keep 3h.It is down to room temperature (20-25 DEG C)
Lead to hydrogen 2 hours afterwards, reduce rear water washing 3 times, be then transferred in beaker, addition 0.5g above-mentioned cn carrier, room temperature
Stirring 12h, is washed with deionized 3 times, 60 DEG C are dried 12h.Lead to hydrogen reducing in tube furnace, 10 DEG C/min rises to 500 DEG C,
Keep 3h, obtain comparative catalyst l.
Catalyst performance evaluation:
(1) 2- methyl -3- butyne-2-alcohol selective hydrogenation 2-M3BOL reaction
Catalyst 0.4g, 2- methyl -3- butyne-2-alcohol 150g and water 50g is added in 500ml autoclave.Autoclave is successively
With nitrogen, hydrogen exchange 3 times.Continuously it is passed through hydrogen and keeps Hydrogen Vapor Pressure 1.0-2.0mpa, controlling reaction temperature is in 60-80
℃.Reach sample analysis product composition after reaction end.Then lower the temperature, filter to isolate catalyst, Fig. 2 gives catalyst a
Recycled situation in the reaction, wherein, abscissa is to apply mechanically number of times, and vertical coordinate is selectivity, urges as can be seen from Figure 2
After 80 times are applied mechanically, selectivity no substantially reduces agent.
(2) dehydrogenation linalool selective hydrogenation linalool (3,7- dimethyl -1,6- octadiene -3- alcohol) reaction
Catalyst 0.4g, dehydrogenation linalool 100g and ethanol 100g is added in 500ml autoclave.Autoclave priority nitrogen
Gas, hydrogen exchange 3 times.Continuously it is passed through hydrogen and keeps Hydrogen Vapor Pressure 1.0-2.0mpa, controlling reaction temperature is at 30-50 DEG C.Reach
The sample analysis product composition to after reaction end.Then lower the temperature, filter to isolate catalyst, catalyst is capable of circulation to be applied mechanically.
(3) dehydrogenation different vegetable alcohol selective hydrogenation different vegetable alcohol (3,7,11,15- tetramethyl-cetene -3- alcohol)
Reaction
Catalyst 0.4g, dehydrogenation different vegetable alcohol 100g and ethanol 100g is added in 500ml autoclave.Autoclave priority nitrogen
Gas, hydrogen exchange 3 times.Continuously it is passed through hydrogen and keeps Hydrogen Vapor Pressure 1.0-2.0mpa, controlling reaction temperature is at 60-85 DEG C.Reach
The sample analysis product composition to after reaction end.Then lower the temperature, filter to isolate catalyst, catalyst is capable of circulation to be applied mechanically.
For three of the above reaction, when the content of reactant alkynol is down to below 0.3%, stopped reaction, sample analysis.
Concrete reaction result is shown in Table 1.
The reaction evaluating result of table 1 catalyst
The result of table 1 shows, can reach commercially available lindlar catalyst using the catalyst of the application similar or more
Good activity and selectivity, but the application does not need using pb as suppression composition, to more environment-friendly.And single cn
Complex carrier or zno carrier are all unable to reach satisfied activity and/or selectivity, even if being doped into zn in active component.