CN102381977B - Preparation of hydrogenated pyromellitic acid ester - Google Patents
Preparation of hydrogenated pyromellitic acid ester Download PDFInfo
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- CN102381977B CN102381977B CN201110332495.4A CN201110332495A CN102381977B CN 102381977 B CN102381977 B CN 102381977B CN 201110332495 A CN201110332495 A CN 201110332495A CN 102381977 B CN102381977 B CN 102381977B
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Abstract
In the invention, a catalyst used for hydrogenation reaction of pyromellitic acid ester to prepare hydrogenated pyromellitic acid ester is prepared, the catalyst is prepared by loading multi-component noble metal on a rare-earth modified and compounded aluminum oxide carrier, and the hydrogenation catalyst has high activity, high selectivity and long life.
Description
Technical field
The present invention relates to prepare the catalyzer preparation of hydrogenation Pyromellitic Acid ester class and use, hydrogenation Pyromellitic Acid ester class is to be prepared by Pyromellitic Acid ester class hydrogenation reaction, under certain temperature, hydrogen pressure and catalyst action, phenyl ring in Pyromellitic Acid ester quasi-molecule is carried out after saturated hydrogenation, a kind of alicyclic quaternary ester obtaining, prepares hydrogenated pyromellitic anhydride as fine-chemical intermediate.In invention, prepared catalyzer is applicable to the shortening process of Pyromellitic Acid ester class, has the feature of high reactivity, highly selective.
Background technology
Hydrogenated pyromellitic anhydride (HPMDA) is a kind of novel alicyclic acid anhydrides, for the preparation of hydrogenated pyromellitic anhydride type polyimide (PI).HPMDA is owing to not containing aromatic component in molecular structure, therefore polyimide prepared therefrom (PI) has the good transparency, low-k and dielectric loss, high disruptive strength, low rate of moisture absorption and the adhesivity good with the base material such as metal, in fields such as aerospace, automobile, microelectronics, large-scale integrated circuit, semiconductor material and flat-panel monitors, has broad application prospects.Meanwhile, HPMDA type PI film has good heat-resistant stability, good mechanical property and optical property, in numerous high-tech sectors, is widely used.
From prior art, the preparation of HPMDA is mainly completed by following reaction:
1, Pyromellitic Acid shortening obtains hydrogenation Pyromellitic Acid
2, hydrogenation Pyromellitic Acid cyclodehydration is prepared HPMDA
Technology emphasis is preparation hydrogenation Pyromellitic Acid, and the key of reaction is the hydrogenation reaction of the first step.The hydrogenation of Pyromellitic Acid belongs to aromatics hydrogenation, the category that belongs to benzene ring hydrogenation, its key problem in technology is the selection of activity of hydrocatalyst component and carrier, the material that in theory benzene ring hydrogenation is played to katalysis can be applied to the hydrogenation process of Pyromellitic Acid, catalyzer mainly adopts noble metal carrier catalyst at present, general reaction conditions is 50~300 ℃, hydrogen pressure 1~30MPa, can adopt intermittence or continuous hydrogenation technical process, reaction product is used recrystallizing technology to carry out separating-purifying.European patent EP 1323700 directly be take Pyromellitic Acid as raw material, use high capacity amount catalyzer to carry out hydrogenation as 5%Rh/C or 5%Ru/C, when employing autoclave hydrogenation at intermittence, catalyzer initial activity and selectivity are good, but catalyzer is easily covered pollution by raw material or product absorption, duration of service is short, must frequently carry out the activation treatment of catalyzer, in commercial production, increased the operation easier of aftertreatment separating-purifying, finally cause HPMDA yield to reduce, while adopting continuous fixed bed hydrogenation technique, reaction pressure is up to 12MPa, catalyst loading≤0.1h
-1(wt).In patent JP2006083080, adopt 5%Rh/ aluminum oxide as catalyzer, the Pyromellitic Acid of directly take is prepared HPMDA as raw material, and in reaction process, hydrogenation Pyromellitic Acid yield is low, final overall HPMDA yield 70%.In prior art, be mainly to take Pyromellitic Acid as raw material direct hydrogenation, raw material or product are all acid, easily be attached to catalyst surface, affect the activity of catalyzer, reduced transformation efficiency, increase the operation easier of separating-purifying, the use of the amount of high capacity simultaneously precious metal, has also reduced economic feasibility.
Comprehensive prior art, in the preparation of HPMDA, key problem in technology is the preparation of hydrogenation Pyromellitic Acid, in material choice, can be Pyromellitic Acid or its ester class, directly take that the former adopts intermittently autoclave hydrogenation technique as raw material more, the latter of take can realize serialization fixed-bed process route as raw material, take Pyromellitic Acid ester class as hydrogenating materials can reach high conversion, highly selective, is the High-efficient Production of acquisition hydrogenation Pyromellitic Acid ester, and the technological line adopting in invention is:
1, prepare composite modified carrier
2, load polycomponent precious metal
3, adopt fixed-bed process to carry out Pyromellitic Acid ester through hydrogenation and prepare hydrogenation Pyromellitic Acid ester
Technology focuses on the catalyst hydrogenation of Pyromellitic Acid ester, because the solubility property of Pyromellitic Acid ester class in multiple organic solvent is good, be conducive to the mass transfer in reaction process, can under high catalysis load, carry out the hydrogenation reaction of phenyl ring, overcome the shortcoming of Pyromellitic Acid hydrogenation reaction, as in Japanese Patent JP2006045166 in preparing hydrogenated pyromellitic anhydride, take Pyromellitic Acid as raw material, first generate its ester, under ruthenium (Ru) catalyzer, carry out again the hydrogenation of phenyl ring, finally be hydrolyzed, cyclodehydration is prepared HPMDA, although preparation process increases, but catalyst loading is improved, life, greatly reduce the consumption of precious metal, more be conducive to commercially produce.
Technology focuses on the preparation of hydrogenation Pyromellitic Acid ester at present, feature for Pyromellitic Acid ester molecular structure, on phenyl ring, there are four ester group substituents, the increasing of molecule space size, require carrier to have larger aperture, the existence of four ester groups has simultaneously reduced the reactive behavior of phenyl ring, requires catalyzer to have higher catalytic activity, the key point of technology is the preparation of carrier and the selection of active ingredient, prepares the catalyzer of high reactivity, highly selective.
Summary of the invention
The present invention has prepared efficient Pyromellitic Acid ester class hydrogenation catalyst, adopts serialization fixed-bed process to prepare hydrogenation Pyromellitic Acid ester, as the raw material of preparing hydrogenated pyromellitic anhydride.This invention solved existing directly take Pyromellitic Acid as raw material Hydrogenation fast for catalyst deactivation in hydrogenation Pyromellitic Acid technology, life-span is short, the shortcoming that needs frequent regeneration in use, in the present invention, adopt rare earth modified composite aluminium sesquioxide to do carrier, prepared wide aperture carrier, for the hydrogenation of large size reactant molecule provides favourable reaction environment, simultaneously by introducing thulium, improve the dispersity of active ingredient on this carrier, improved the anti-caking power of precious metal element crystallite under high temperature hydrogenation reaction conditions, for catalyzer provides longer hydrogenation work-ing life.By the enforcement of above technology, a kind of high reactivity of applicable preparation hydrogenation Pyromellitic Acid ester, the hydrogenation catalyst of highly selective have been invented.Technology implementation method of the present invention is as follows:
1. the preparation of composite alumina supporter:
Get commercially available pseudo-boehmite, aluminium hydroxide powder and be mixed into by a certain percentage uniform powder, take the aqueous solution of quantitative rare nitric acid, phosphoric acid preparation, in kneader, first the solution of preparation is evenly sprayed in powder, again the aqueous solution containing expanding agent is evenly sprayed in compound, after aging certain hour, extrusion moulding on twin screw extruder, roasting under pre-set programs temperature control after dry, obtain the composite aluminum oxide of strip, pulverize and sieve and get certain granules degree carrier, the composite alumina supporter that obtains using in the present invention.
2. carrier pre-treatment:
Carrier pretreatment component is selected from rare earth element, comprises La, Sr, at least wherein a kind of, consists of.Rare earth nitrate aqueous solution dipping by the above-mentioned carrier having weighed by the metering concentration configuring, is dried, roasting afterwards, the rare earth modified composite alumina supporter that obtains using in the present invention.
By above-mentioned preparation method, can obtain the carrier of following feature, i.e. rare earth modified composite alumina supporter specific surface area 90~120m
2/ g, volume 0.5~0.7ml/g, its mesoporous
account for total pore volume more than 50%.
3. the dipping of active ingredient:
Catalytic active component is selected from precious metal element, for two-pack forms, comprises two kinds of elements in Pd, Ru, Rh.Adopt conventional dipping method to carry out the dip loading of active ingredient, use the muriate mixed aqueous solution of palladium, ruthenium or the rhodium of metering concentration to flood support of the catalyst, after dry, under controlling, temperature programming carries out roasting, reduction activation in reactor before hydrogenation reaction, obtains catalyzer described in the present invention.
4. catalyst activity and life assessment method:
Pyromellitic Acid ester is dissolved in representative examples of saturated aliphatic alcohol, forms the material solution of 20%~25% (wt) concentration.In single tube fixed-bed reactor, pack catalyzer into, reduction activation under temperature programming in atmosphere of hydrogen, passes into material solution in reactor, to carry out hydrogenation reaction, reaction conditions through volume pump: pressure 6.0Mpa, 220 ℃ of bed temperatures, liquid air speed 4.0h
-1(V), hydrogen gas space velocity 250h
-1(V),, after hydrogenation mix products is cooling, the mix products of the hydrogenation Pyromellitic Acid ester that obtains containing solvent, carries out liquid phase analysis of hplc.
Contriver adopts fixed bed hydrogenation technical process, by great many of experiments, find, catalyzer prepared by application aforesaid method, can make the transformation efficiency of Pyromellitic Acid ester class be greater than 99%, the selectivity of hydrogenation Pyromellitic Acid ester is greater than 98%, after underpressure distillation desolvation, overall yield is greater than 97%, and product purity reaches 99.5%.Meanwhile, carry out continuous 1000 hours hydrogenation reactions, transformation efficiency keeps more than 98%, and selectivity remains on more than 97%.
Accompanying drawing explanation
Accompanying drawing is catalyst stability figure of the present invention.
Embodiment
By following examples, the preparation of the catalyzer in the present invention and use are described.
Embodiment 1
Get commercially available pseudo-boehmite, aluminium hydroxide powder and be mixed into by a certain percentage uniform powder, take quantitative rare nitric acid, phosphorylated ligand is made the aqueous solution, in kneader, first the solution of preparation is evenly sprayed in powder, again the aqueous solution of quantitative polyoxyethylene glycol is evenly sprayed in compound, after aging certain hour, extrusion moulding on twin screw extruder, roasting under pre-set programs temperature control after dry, obtain the composite aluminum oxide of strip, pulverize and sieve and get certain granules degree carrier, the catalyst compounded carrier that obtains using in the present invention.According to different proportioning raw materials, be prepared as follows 1~7 carrier:
The preparation and characterization of the composite alumina supporter of table one
Embodiment 2
Take respectively 1~7 carrier 100g in embodiment 1, put into respectively the strontium nitrate aqueous solution dipping 24 hours of 100ml (0.012g Sr/ml), in 120 ℃ dry 12 hours, 400 ℃ of roastings afterwards 3 hours, obtain rare earth modified composite alumina supporter.
By above-mentioned pretreated carrier, put into respectively the mixed aqueous solution that 125ml contains ruthenium chloride and rhodium chloride, wherein Ru content 0.002g/ml, Rh content 0.0004g/ml, flood after 24 hours 120 ℃ dry 6 hours, repeat aforesaid operations 4 times, after dry, in 400 ℃ of roastings 4 hours, obtain corresponding H-1, H-2, H-3, H-4, H-5, H-6, H-7 catalyzer, load 1%Ru and 0.2%Rh.
Embodiment 3
Pyromellitic Acid four butyl esters are dissolved in butanols, form the butanol solution of Pyromellitic Acid four butyl esters contain 23% (wt), with this as reaction raw materials solution.In single tube fixed-bed reactor, pack catalyzer into, reduction activation under temperature programming in atmosphere of hydrogen, passes into material solution in reactor, to carry out hydrogenation reaction, reaction conditions through volume pump: pressure 6.0Mpa, 220 ℃ of bed temperatures, liquid air speed 4.0h
-1(V), hydrogen gas space velocity 250h
-1(V),, after hydrogenation mix products is cooling, the mix products of hydrogenation Pyromellitic Acid four butyl esters that obtain containing solvent butanols, carries out stratographic analysis, as follows:
The evaluation of table two catalyst activity
Catalyzer | Transformation efficiency (%) | Selectivity (%) |
H-1 | 99.6 | 98.4 |
H-2 | 99.1 | 98.0 |
H-3 | 99.4 | 98.2 |
H-4 | 99.0 | 9.6 |
H-5 | 99.8 | 99.1 |
H-6 | 71.1 | 68.9 |
H-7 | 36.4 | 70.5 |
Embodiment 4
Adopt carrier 5, according to the method for embodiment 2, prepare different activities component concentration catalyzer, carry out activity rating, as follows:
Table three different activities component concentration evaluating catalyst
Catalyzer | Active ingredient forms | Transformation efficiency (%) | Selectivity (%) |
H-8 | 0.6%Pd、1.0%Rh | 99.6 | 98.4 |
H-9 | 2%Ru、0.5%Rh | 99.1 | 99.0 |
H-10 | 2%Pd、0.5%Ru | 99.5 | 99.1 |
H-11 | 1.5%Ru、0.1%Rh | 99.4 | 98.3 |
Embodiment 5
Adopt carrier 5, according to the method for embodiment 2, prepare different ree content catalyzer, carry out activity rating, as follows:
The different content of rare earth evaluating catalysts of table four
Catalyzer | Ree content | Transformation efficiency (%) | Selectivity (%) |
H-12 | 0.6%La | 99.1 | 98.2 |
H-13 | 1.2%La | 99.4 | 98.6 |
H-14 | 2%La | 99.3 | 98.3 |
H-15 | 0.6%Sr | 99.4 | 98.4 |
H-16 | 2%Sr | 99.5 | 98.1 |
H-17 | 0.6%Sr、0.6%La | 99.1 | 98.5 |
Embodiment 6
Adopt H-5 catalyzer, use the material solution of different ester classes and different solvents to carry out hydrogenation reaction, reaction conditions is identical with embodiment 3, reacts as follows:
The hydrogenation of table five different material solution
Embodiment 7
Adopt catalyzer H-5 according to the processing condition of embodiment 3, carry out continuous hydrogenation reaction in 1000 hours, response data is as follows: see accompanying drawing.
Claims (4)
1. the hydrogenation catalyst for the preparation of hydrogenation Pyromellitic Acid ester, it is characterized in that: this catalyzer comprises 100 weight parts by phosphorus, expanding agent and rare-earth metal modified composite alumina supporter, and load 1.0~3.0 weight parts are as the precious metal of active ingredient; Wherein, described composite alumina supporter is comprised of 30~80 weight part pseudo-boehmites, 10~40 weight part aluminium hydroxides, 5~10 weight part expanding agents, 0.5~2 weight part thulium, 1~5 weight part phosphoric; Described expanding agent is one or more that are selected from methylcellulose gum, sodium stearate, polyoxyethylene glycol and starch; Described thulium is selected from least one in La, Sr; Described phosphoric is selected from phosphoric acid, phosphorous acid; Described precious metal is selected from two kinds in Pd, Ru, Rh.
2. a kind of hydrogenation catalyst for the preparation of hydrogenation Pyromellitic Acid ester according to claim 1, is characterized in that: the amount of described Ru is 0.5~2.0 weight part.
3. a kind of hydrogenation catalyst for the preparation of hydrogenation Pyromellitic Acid ester according to claim 1, is characterized in that: the amount of described Pd is 0.5~2.0 weight part.
4. a kind of hydrogenation catalyst for the preparation of hydrogenation Pyromellitic Acid ester according to claim 1, is characterized in that: the amount of described Rh is 0.1~1.0 weight part.
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CN103480339B (en) * | 2012-06-12 | 2015-11-25 | 中国石油化工股份有限公司 | Hydrated alumina forming matter and preparation method thereof and aluminium oxide article shaped and their application |
CN103480390B (en) * | 2012-06-12 | 2015-08-26 | 中国石油化工股份有限公司 | There is the Catalysts and its preparation method of hydrogenation catalyst effect and application and method for hydrotreating hydrocarbon oil |
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CN103480423B (en) * | 2012-06-12 | 2015-08-26 | 中国石油化工股份有限公司 | There is the Catalysts and its preparation method of hydrogenation catalyst effect and application and hydrotreating method |
CN102921440A (en) * | 2012-10-26 | 2013-02-13 | 中国石油化工股份有限公司 | Catalyst for preparation of hydrogenated bisphenol A |
CN104560410B (en) * | 2013-10-23 | 2017-05-17 | 中国石油化工股份有限公司 | Method for preparing biodiesel using tung oil |
CN106866415A (en) * | 2015-12-12 | 2017-06-20 | 中国科学院大连化学物理研究所 | A kind of manufacture method of alicyclic carboxylic ether |
CN108187705A (en) * | 2017-12-04 | 2018-06-22 | 天津大学 | A kind of Al of rare earth metal and phosphorus modified synergic2O3Particle and preparation method thereof |
CN109896958B (en) * | 2017-12-07 | 2021-06-01 | 中国科学院大连化学物理研究所 | Synthesis method of 1,2,4, 5-cyclohexane tetracarboxylate |
TWI690510B (en) * | 2018-12-04 | 2020-04-11 | 南亞塑膠工業股份有限公司 | Hydrogenation method for improving yield of diisooctyl cyclohexane-1,4-dicarboxylate |
CN114177946B (en) * | 2020-09-14 | 2023-08-29 | 中国石油化工股份有限公司 | Catalyst for synthesizing hydrogenated pyromellitic acid |
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Effective date of registration: 20170920 Address after: 264204, room 985-7, Fenghuang Mountain Road, sheep town, Huancui District, Shandong, Weihai, 301 Patentee after: Weihai Xinyuan Keshengxin Material Co. Ltd. Address before: 264309 No. 255 Dongshan South Road, Shandong, Rongcheng Patentee before: Rongcheng Kesheng Chemical Co., Ltd. |