CN102935375B - 3-methyl lactate hydrogenation catalyst and preparation method thereof - Google Patents
3-methyl lactate hydrogenation catalyst and preparation method thereof Download PDFInfo
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Abstract
The invention relates to a 3-methyl lactate hydrogenation catalyst which is composed of, by weight, 30-90% of Cu, 9-30% of Mo and 1-60% of C. The preparation steps include: (1) dissolving precursors of Cu and Mo elements in deionized water according to proportion, and mixing evenly; (2) weighing the precursors of a C element according to 1.8-3-times of stoichiometric ratio, then soaking in an organic acid solution, washing and filtering; (3) mixing substances in the step (1) and the step (2), then drying, tabletting and molding; and (4) roasting and passivating to obtain the catalyst. The catalyst is applied to hydrogenation preparing of 1,3-propylene glycol through 3- methyl lactate, conversion rate of the 3-methyl lactate is approximately 100%, and selectivity of 1,3-propylene glycol is more than 80%.
Description
Technical field
The present invention relates to a kind of 3-hydroxy methyl propionate hydrogenation catalyst and preparation method thereof and application, belong to hydrogenation catalyst field.
Technical background
1,3-PD is important Organic Chemicals, and the application of its maximum is to carry out polymerization with terephthalic acid (TPA) to obtain PTT polyester.PTT polyester property is good, has good resilience, workability, easy dyeing and bulkiness etc., and market prospects are wide.
Present stage 1, the synthetic route of ammediol mainly contains: the epoxyethane method of Shell Co. Ltd of (1) U.S., adopts Hydroformylation of Ethylene Oxide For 3-hydroxypropanal Synthesis, then hydrogenation synthetic 1, ammediol, is shown in patent US 5723389, US 6180838, US 8013192; (2) acryladehyde method of Degussa, adopts acrolein hydration to generate 3-HPA, and then the synthetic 1,3-PD of hydrogenation, is shown in patent US6232511, US6140543 etc.; (3) bioanalysis of du pont company, produces 1,3-PD as initiation material by biofermentation taking cereal or glycerine, sees patent EP361082, DE3734764 etc.; (4) the oxirane carbonylation esterification process of Dai Wei-Samsung, adopt by the synthetic 3-hydroxy ester of carbonyl esterification process that react such as oxirane and carbon monoxide and alcohol, then by the method for the synthetic 1,3-PD of its ester group hydrogenation, see patent US 6191321 and CN1412171.
First three methods is industrialization.Wherein the synthetic 1,3-PD of shell and Degussa technique all will be taking 3-HPA as intermediate, and this intermediate is unstable, easily form oligomer and acetal etc., in follow-up hydrogenation reaction, 3-HPA concentration is low, this brings difficulty to hydrogenation technique, and production efficiency is not high.Microbial method to bacterial classification require high, and follow-up separate complex, production efficiency is low, on cost, also cannot compete with chemical method.It is intermediate hydrogenation that the synthetic route of Dai Wei-Samsung adopts comparatively stable 3-hydroxy ester, has very high production efficiency.But due to the non-selective hydrogenation of conventional catalyst, make the method there is no so far industrialized example.
For solving problems, Samsung of Korea S adopts with CuO/SiO
2for catalyst, 3-hydroxy methyl propionate hydrogenation reaction conversion ratio can reach 90%, and 1,3-PD selectively can reach 85%.But in hydrogenation, in order to improve the performance of catalyst, add a large amount of methyl alcohol and high boiling point organic compound in hydrogenating materials, cause using the 3-hydroxy methyl propionate concentration of raw material lower, this causes very large difficulty to follow-up Separation & Purification.In catalyst preparation process process, adopt NaOH as precipitating reagent, the washing of catalyst is loaded down with trivial details, consumes a large amount of deionized waters simultaneously.
Summary of the invention
The object of the invention is to overcome the defect of above-mentioned existing 3-hydroxy methyl propionate Hydrogenation for 1,3 propane diols technology, a kind of Catalysts and its preparation method that can be used for the synthetic 1,3-PD of high concentration 3-hydracrylic acid ester through hydrogenation is provided.
Technical scheme of the present invention realizes by following technical characterictic:
A kind of 3-hydroxy methyl propionate hydrogenation catalyst, is made up of the component of following percentage by weight: Cu:30～90%, Mo:9～30%, C:1～60%.
Preferably, Cu:55～70%, Mo:10～30%, C:10～30%.
The present invention also provides a kind of preparation method of 3-hydroxy methyl propionate hydrogenation catalyst, comprises the following steps:
(1) by proportioning, the predecessor of Cu, Mo element is dissolved in deionized water, evenly mixes;
(2) doubly take the predecessor of C element by the 1.8-3 of metering ratio, then soak with aqueous solutions of organic acids, wash afterwards, filter;
(3) step (1) and step (2) material that obtains are mixed, then dry, compression molding;
(4) after roasting, passivation, make described 3-hydroxy methyl propionate hydrogenation catalyst.
Wherein,
The predecessor of described Cu element is selected from Schweinfurt green.
The predecessor of described Mo element is selected from ammonium molybdate.
The predecessor of described C element is selected from cyclodextrin and starch.
Described in step (2), organic acid is selected from acetic acid and citric acid; The mass percent concentration of described aqueous solutions of organic acids is 1-10wt%, and the temperature of described immersion is normal temperature.
Described in step (2), the washing agent of washing is deionized water, and the object of described washing is that wash temperature is normal temperature in order to remove the metal ion in C element predecessor.
Described in step (3), dry temperature is 80-120 DEG C, and the dry time is 2-10 hour.
Described in step (4), roasting is carried out in two steps: first low-temperature bake, and the atmosphere of roasting is air, and temperature is 130-300 DEG C, and the time is 1-5 hour; Then high-temperature roasting, the atmosphere of roasting is inert atmosphere N
2or Ar, temperature is 700-900 DEG C, the time is 3-7 hour.
Described in step (4), the technical process of passivation is: treat that temperature is down to room temperature, add appropriate oxygen or air in the inert atmosphere of described high-temperature roasting, make the volume of oxygen account for the 0.1-5% of volume of gas, passivation 8 hours.
In described catalyst, Mo is mainly with Mo
2the form of C exists, and C is with Mo
2the form of C and agraphitic carbon exists; In described catalyst preparation process, unnecessary C reacts with the oxide of water, cupric oxide, molybdenum and forms carbon monoxide or carbon dioxide and run off.
The granularity of described catalyst is 40-60 order.
The technique effect that the present invention obtains: by add C and Mo element in Cu series catalysts, prepare for the synthesis of 1, the catalyst of ammediol, this catalyst is used for to 3-hydroxy methyl propionate Hydrogenation for 1, in ammediol technique, success improves the yield of hydrogenation process raw material 3-hydroxy methyl propionate concentration and 1,3-PD with selective, and has reduced the content of solvent simultaneously.Compared with prior art tool has the following advantages:
1, preparation process is simple, and wastewater treatment capacity is few;
2,1,3-PD selectively reaches more than 80%;
3, material concentration is high, and solvent is few, can be directly by the high-load 3-hydroxy methyl propionate direct hydrogenation after separating;
4, in catalyst preparation, add starch or cyclodextrin, in dry and roasting process, form Mo
2c and unformed porous carbon, improved specific surface area of catalyst, stability and activity.
Detailed description of the invention
By specific instantiation, technical scheme of the present invention is described below.Should be understood that one or more method steps that the present invention mentions do not repel between the step that also has additive method step or clearly mention at these before and after described combination step can also insert additive method step; Should also be understood that these embodiment are only not used in and limit the scope of the invention for the present invention is described.And, except as otherwise noted, the numbering of various method steps is only for differentiating the convenient tool of various method steps, but not for limiting the ordering of various method steps or limiting the enforceable scope of the present invention, the change of its relativeness or adjustment, in the situation that changing technology contents without essence, when being also considered as the enforceable category of the present invention.
Embodiment 1
The 3-hydroxy methyl propionate hydrogenation catalyst that preparation Cu:Mo:C weight ratio is 45:18:7:
(1) by proportioning, Schweinfurt green and ammonium molybdate are dissolved in deionized water, are uniformly mixed at normal temperatures;
(2) metered 3 times take starch, then soak with 2wt% aqueous acetic acid, aqueous acetic acid quality is starch quality 5 times, then with the deionized water washing of equal quality, filter three times;
(3) mixture step (1) being obtained joins rapidly in the starch that step (2) obtains and mixes, and then at 110 DEG C dry 10 hours, rear compression molding;
(4) then 130 DEG C of roastings 5 hours in air, roasting 7 hours under 700 DEG C of nitrogen atmospheres afterwards; Then be cooled to after room temperature, in aforesaid nitrogen, pass into air, the volume of oxygen is accounted for overall 1%, passivation 8 hours; Take out catalyst, be broken for after 40～60 orders.Then deduct elemental copper (calculating by copper) with total catalyst quality and molybdenum carbide (calculating by ammonium molybdate) quality is agraphitic carbon quality, can calculate the quality of carbon in molybdenum carbide by ammonium molybdate quality, both addition calculation go out carbon amount total in catalyst.The 3-hydroxy methyl propionate hydrogenation catalyst that such Cu:Mo:C weight ratio is 45:18:7.
The catalyst of aforementioned roasting moulding is packed in tubular reactor, at 180 DEG C, 5%H
2/ 95%N
2under mist condition, reductase 12 4 hours, switches to H
2react.Reaction condition is P=7.0Mpa, T=160 DEG C, liquid hourly space velocity (LHSV)=0.1h
-1, hydrogen ester ratio is 180, and raw material 3-hydroxy methyl propionate concentration is 10wt%, and hydrogenation result is: 3-hydroxy methyl propionate conversion ratio is 70%, and 1,3-PD is selectively 82%, and methyl propionate is selectively 8%, and normal propyl alcohol is selective 8%, and other is 2% years old.
Embodiment 2
The 3-hydroxy methyl propionate hydrogenation catalyst that preparation Cu:Mo:C weight ratio is 3:1:1:
(1) by proportioning, Schweinfurt green and ammonium molybdate are dissolved in deionized water, are uniformly mixed at normal temperatures;
(2) metered 1.8 times take starch, then soak with 4 times of aqueous citric acid solutions to the 6wt% of starch quality, then use etc. quality deionized water washing, filter twice;
(3) mixture step (1) being obtained joins rapidly in the starch that step (2) obtains and mixes, then dry compression molding after 6 hours at 120 DEG C;
(4) then 300 DEG C of roastings 4 hours in air, then roasting 5 hours under 800 DEG C of nitrogen atmospheres, is then down to room temperature, in aforesaid nitrogen, passes into oxygen, makes the volume content of oxygen account for 2% of cumulative volume, passivation 4 hours; Take out catalyst, be broken for 40～60 orders, then deduct elemental copper (calculating by Schweinfurt green) with total catalyst quality and molybdenum carbide (calculating by ammonium molybdate) quality is agraphitic carbon quality, can calculate the quality of carbon in molybdenum carbide by ammonium molybdate quality, both addition calculation go out carbon amount total in catalyst.The 3-hydroxy methyl propionate hydrogenation catalyst that such Cu:Mo:C weight ratio is 3:1:1.
The catalyst of aforementioned roasting moulding is packed in tubular reactor, at 180 DEG C, 5%H
2/ 95%N
2under mist condition, reductase 12 4 hours, switches to H
2react.Reaction condition is P=7.0Mpa, T=160 DEG C, liquid hourly space velocity (LHSV)=0.1h
-1, hydrogen ester ratio is that 180,3-hydroxy methyl propionate concentration is 10wt%.Hydrogenation result is: 3-hydroxy methyl propionate conversion ratio is 90%, and 1,3-PD is selectively 80%, and methyl propionate is selectively 6%, and normal propyl alcohol is selective 5.5%, propionic acid 1,3-PD monoesters 6%, and other is 2.5% years old.
Embodiment 3
The 3-hydroxy methyl propionate hydrogenation catalyst that preparation Cu:Mo:C weight ratio is 49:14:27:
(1) by proportioning, Schweinfurt green and ammonium molybdate are dissolved in deionized water, are uniformly mixed at normal temperatures;
(2) metered 2.5 times take starch, then soak to the 1wt% of starch quality aqueous acetic acid with 6 times, then use etc. quality deionized water washing, filter twice;
(3) mixture step (1) being obtained joins rapidly in the starch that step (2) obtains and mixes, then dry compression molding after 6 hours at 120 DEG C;
(4) then 250 DEG C of roastings 5 hours in air, then roasting 4 hours under 900 DEG C of nitrogen atmospheres; Then be down to room temperature, in aforesaid nitrogen, pass into air, make the volume content of oxygen account for 1% of volume of gas, passivation 8 hours, take out catalyst, be broken for after 40～60 orders, deduct elemental copper (calculating by Schweinfurt green) and molybdenum carbide (calculating by ammonium molybdate) quality is agraphitic carbon quality with total catalyst quality, can calculate the quality of carbon in molybdenum carbide by ammonium molybdate quality, both addition calculation go out carbon amount total in catalyst.The 3-hydroxy methyl propionate hydrogenation catalyst that such Cu:Mo:C weight ratio is 49:14:27.
The catalyst of aforementioned roasting moulding is packed into and run affairs in reactor, at 200 DEG C, 5%H
2/ 95%N
2under mist condition, reductase 12 4 hours, switches to H
2react.Reaction condition is P=6.0Mpa, T=165 DEG C, liquid hourly space velocity (LHSV)=0.2h
-1, hydrogen ester ratio is that 230,3-hydroxy methyl propionate concentration is 10wt%.Hydrogenation result is: 3-hydroxy methyl propionate conversion ratio is 95%, and 1,3-PD is selectively 82%, and methyl propionate is selectively 8.5%, and normal propyl alcohol is selective 7.5%, and other is 2% years old.
Embodiment 4
The 3-hydroxy methyl propionate hydrogenation catalyst that preparation Cu:Mo:C weight ratio is 49:14:20:
(1) by proportioning, Schweinfurt green and ammonium molybdate are dissolved in deionized water, are uniformly mixed at normal temperatures;
(2) metered 2 times take cyclodextrin, then soak to the 1wt% of starch quality aqueous acetic acid with 3 times, then use etc. quality deionized water washing, filter twice;
(3) mixture step (1) being obtained joins rapidly in the starch that step (2) obtains and mixes, then dry compression molding after 6 hours at 120 DEG C;
(4) then 250 DEG C of roastings 5 hours in air, then roasting 4 hours under 700 DEG C of nitrogen atmospheres, then be down to room temperature, in aforesaid nitrogen, pass into air, make the volume content of oxygen account for 1% of volume of gas, passivation 8 hours, take out catalyst, be broken for after 40～60 orders, deduct elemental copper (calculating by Schweinfurt green) and molybdenum carbide (calculating by ammonium molybdate) quality is agraphitic carbon quality with total catalyst quality, can calculate the quality of carbon in molybdenum carbide by ammonium molybdate quality, both addition calculation go out carbon amount total in catalyst.The 3-hydroxy methyl propionate hydrogenation catalyst that such Cu:Mo:C weight ratio is 49:14:20.
The catalyst of aforementioned roasting moulding is packed into and run affairs in reactor, at 180 DEG C, 5%H
2/ 95%N
2under mist condition, reductase 12 4 hours, switches to unstripped gas and reacts.Reaction condition is P=6.0Mpa, T=163 DEG C, liquid hourly space velocity (LHSV)=0.15h
-1, hydrogen ester ratio is that 200,3-hydroxy methyl propionate concentration is 99wt%.Hydrogenation result is: 3-hydroxy methyl propionate conversion ratio is 99.6%, and 1,3-PD is selectively 85%, and methyl propionate is selectively 4.5%, and normal propyl alcohol is selective 5%, 1,3-PD propionic acid monoesters 4.5%, and other is 1% years old.
Claims (8)
1. a 3-hydroxy methyl propionate hydrogenation catalyst, is made up of the elemental constituent of following percentage by weight:
Cu：30～90%，Mo：9～30%，C：1～60%；
In described catalyst, Mo is mainly with Mo
2the form of C exists, and C is with Mo
2the form of C and agraphitic carbon exists.
2. the preparation method of a kind of 3-hydroxy methyl propionate hydrogenation catalyst as claimed in claim 1, comprises the steps:
(1) by proportioning, the predecessor of Cu, Mo element is dissolved in deionized water, evenly mixes;
(2) doubly take the predecessor of C element by the 1.8-3 of metering ratio, then soak with aqueous solutions of organic acids, wash afterwards, filter;
(3) step (1) and step (2) material that obtains are mixed, then dry, compression molding;
(4) after roasting, passivation, make described 3-hydroxy methyl propionate hydrogenation catalyst;
Described in step (4), roasting is carried out in two steps: first low-temperature bake, and the atmosphere of roasting is air, and temperature is 130-300 DEG C, and the time is 1-5 hour; Then high-temperature roasting, the atmosphere of roasting is inert atmosphere N
2or Ar, temperature is 700-900 DEG C, the time is 3-7 hour.
3. preparation method as claimed in claim 2, is characterized in that, the predecessor of described Cu element is selected from Schweinfurt green, and the predecessor of described Mo element is selected from ammonium molybdate, and the predecessor of described C element is selected from cyclodextrin and starch.
4. preparation method as claimed in claim 2, is characterized in that, described in step (2), organic acid is selected from acetic acid and citric acid.
5. preparation method as claimed in claim 2, is characterized in that, described in step (2), the washing agent of washing is deionized water.
6. preparation method as claimed in claim 2, is characterized in that, described in step (3), dry temperature is 80-120 DEG C, and the dry time is 2-10 hour.
7. preparation method as claimed in claim 2, it is characterized in that, described in step (4), the technical process of passivation is: treat that temperature is down to room temperature, add appropriate oxygen or air in the inert atmosphere of described high-temperature roasting, make the volume of oxygen account for the 0.1-5% of volume of gas, passivation 8 hours.
One kind as claimed in claim 1 catalyst produce the application in 1,3-PD technique at 3-hydroxy methyl propionate hydrogenation.
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