CN1589961A - Dehydrogen catalyst for preparing phenyl ethylene from ethylbenzene - Google Patents

Dehydrogen catalyst for preparing phenyl ethylene from ethylbenzene Download PDF

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CN1589961A
CN1589961A CNA031507174A CN03150717A CN1589961A CN 1589961 A CN1589961 A CN 1589961A CN A031507174 A CNA031507174 A CN A031507174A CN 03150717 A CN03150717 A CN 03150717A CN 1589961 A CN1589961 A CN 1589961A
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ethylbenzene
oxide compound
metal
dehydrogenation catalyst
oxide
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CN1302847C (en
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缪长喜
宋磊
徐永繁
杨诚
毛连生
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China Petroleum and Chemical Corp
Sinopec Shanghai Research Institute of Petrochemical Technology
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China Petroleum and Chemical Corp
Sinopec Shanghai Research Institute of Petrochemical Technology
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Abstract

A dehydrocatalyst for preparing styrene from ethylbenzene features that the ppm-class Rh and at least one of Pd, Pt, Ir, Re, Os, Ru and their oxides are simultaneously introduced to the Fe-K-Ce-Mo catalyst system for higher activity, output rate and selectivity.

Description

The dehydrogenation catalyst that is used for preparing styrene from ethylbenzene
Technical field
The present invention relates to be used for the dehydrogenation catalyst of preparing styrene from ethylbenzene.
Background technology
As everyone knows, normally make alkenyl arene by alkyl aromatics catalytic dehydrogenation on the industrial production, selecting a kind of dehydrogenation catalyst efficiently is one of gordian technique of this method.The catalyzer of patent report divides two classes.One class is to contain Cr series, as laid-open U.S. Patents US5376613, US4717781, European patent EP 0794004A1 and German patent DE 2815874A1.Though such activity of such catalysts and stability are better, because catalyst themselves contains environmentally harmful chromated oxide, are very limited on the industrial application, are eliminated gradually.Another kind of is Fe-K-Ce-Mo series, and this type of catalyzer has substituted Cr with Ce, Mo, and activity of such catalysts and stability have by a relatively large margin raising than the former, but the catalyst selectivity aspect still remains to be improved.In addition, the benzene/methylbenzene in the dehydrogenation product, can be delivered to ethylbenzene workshop section to recycle after by products such as benzene separate in the later separation step than an important indicator that also is the decision catalyst efficiency; And toluene can not enter circulation fluid after separating again, needs to enter marketing channel as product, and its economic worth is lower.Therefore, when other index was identical, the higher catalyzer of B/T ratio was the product that production of styrene producer welcomes.For this reason, people have carried out some in this regard and have explored, and studied as laid-open U.S. Patents US6177602 and add the method that Pt, Pd improve catalyst selectivity and reduce the toluene growing amount in the Fe-K-Ce-Mo-Mg system.Because Pt in the document, Pd consumption are higher, about 300ppm, have increased catalyst production cost greatly.A kind of dehydrogenation catalyst that comprises iron, basic metal and precious metal is at least disclosed among document Chinese patent CN1298323A and the US6191065.This catalyzer adds precious metal element, contains the compound of precious metal and the noble metal source of combination thereof in iron cpd and alkalimetal oxide system.Precious metal is selected from platinum, palladium, iridium, rhodium and ruthenium, and its objective is provides a kind of high reactivity and catalyzer optionally, makes the B/T selectivity better simultaneously.See at first the example that openly rhodium and other precious metal element are used in combination from the disclosed content of the document, only disclose the embodiment of independent use rhodium or palladium.The consumption of palladium is minimum in an embodiment is 100ppm, and catalyzer this moment conversion of ethylbenzene under 600 ℃ of temperature only is 47.7%, and selectivity of styrene is 97.3%, and promptly the vinylbenzene yield only is 46.4%, and this moment, B/T was about 0.30; The minimum dosage of rhodium is 10ppm in an embodiment, and this moment, the conversion of ethylbenzene under 600 ℃ of temperature was 40.48%, and cinnamic selectivity is 98.28%, and the vinylbenzene yield only is 39.78%, and the data of B/T are not open.
Summary of the invention
Technical problem to be solved by this invention is that the catalyzer cost is higher in the conventional art, and activity of such catalysts is lower, and the vinylbenzene yield is low, and the low problem of B/T (mole) selectivity provides a kind of new dehydrogenation catalyst that is used for preparing styrene from ethylbenzene.It is low that this catalyzer has a production cost, active high, vinylbenzene yield height, the characteristics that the B/T selectivity is good.
For solving the problems of the technologies described above, the technical solution used in the present invention is as follows: a kind of dehydrogenation catalyst that is used for preparing styrene from ethylbenzene comprises following active constituent by weight percentage:
A) oxide compound of 40～85% iron is with Fe 2O 3Meter;
B) oxide compound of 8～25% potassium is with K 2The O meter;
C) oxide compound of 3～10% ceriums is with Ce 2O 3Meter;
D) oxide compound of 0.5～5% molybdenum is with MoO 3Meter;
E) metal of 1～20ppm rhodium or oxide compound;
F) 1～100ppm is selected from metal at least a among Pd, Pt, Ir, Re, Os or the Ru or oxide compound;
G) 0.5～10% at least a binding agent that is selected from kaolin, diatomite or the cement.
In the technique scheme, preferred version is also to contain alkaline earth metal oxide in the catalyzer, and its consumption is 0.05～8%, and the alkaline earth metal oxide preferred version is a magnesium oxide.The oxide compound preferred version of iron is by Fe 2O 3And Fe 2O 3H 2O forms, and its weight ratio is Fe 2O 3: Fe 2O 3H 2O=0.2～5: 1.The metal of rhodium or oxide compound consumption preferable range are 1.5～9.5ppm by weight percentage, and more preferably scope is 4～8ppm.The consumption that is selected from metal at least a among Pd, Pt, Ir, Re, Os or the Ru or oxide compound preferable range by weight percentage is 1～20ppm, and more preferably scope is 10～20ppm; Being selected from least a metal among Pd, Pt, Ir, Re, Os or the Ru or the preferred version of oxide compound is metal or the oxide compound of Pd.The binding agent preferred version is a cement.
In the dehydrogenation catalyst of the present invention, Fe is with Fe 2O 3Form add Fe 2O 3Formed by red iron oxide, iron oxide yellow and nanometer ferro oxide; Used potassium adds with potassium salt form; Used cerium adds with the form of oxide compound, nitrate, carbonate; Mo adds with its salt or oxide compound; Alkaline earth metal oxide adds with oxide form.The metal of Rh, Pd, Pt, Ir, Re, Os or Ru or oxide compound are with the form adding of nitrate or organic acid salt.
Perforating agent 1～2% can be selected from graphite, polystyrene microsphere, carboxymethyl cellulose; All the other are binding agent, available cement.
Preparation of catalysts method of the present invention:
Will be by behind Fe, the K of proportioning weighing, Ce, Mo, precious metal nitrate, tackiness agent, perforating agent and metal that needs or the oxide composition uniform mixing, add proper amount of deionized water, make the paste of toughness, suitable extrusion, becoming diameter through extrusion, pelletizing is 3 millimeters, long 8～10 millimeters particle, in 60～120 ℃ of dryings 4 hours, 400～1000 ℃ of following roastings 4 hours, just can obtain finished catalyst then.
The catalyzer that makes as stated above carries out activity rating in the isotherm formula fixed bed, for the ethyl benzene dehydrogenation preparation of styrene activity rating, the summary process is as follows:
Deionized water and ethylbenzene are imported preheating mixer through volume pump respectively, and preheating enters reactor after being mixed into gaseous state, and reactor adopts the nichrome wire heating, makes it to reach preset temperature.Reactor inside diameter is 1 " stainless steel tube, interiorly load 100 milliliters, particle diameter is 3 millimeters a catalyzer.Analyzing it with gas chromatograph by the reactant of reactor outflow behind water condensation forms.
Conversion of ethylbenzene and selectivity of styrene calculate as follows:
Figure A0315071700051
The evaluating catalyst condition is as follows: reaction pressure is that normal pressure, 1.0 liters of ethylbenzene of liquid air speed/rise catalyzer hour, temperature of reaction are respectively 620 ℃, 600 ℃, and water is than (water/ethylbenzene) 2.0 (weight ratio).Evaluation result sees Table 1.
Dehydrogenation catalyst of the present invention under certain process conditions, can be applicable to fully that ethylbenzene, diethylbenzene, Alpha-Methyl ethylbenzene dehydrogenation generate vinylbenzene, divinylbenzene and alpha-methyl styrene.
Among the present invention, owing to introduced alkaline-earth metal and precious metal element rhodium in iron-potassium-cerium-molybdenum catalyst system respectively and be selected from metal at least a among Pd, Pt, Ir, Re, Os or the Ru or oxide compound, and their rational amount ranges have been chosen, as rhodium consumption most preferred range only is 4～8ppm, the consumption preferable range that is selected from metal at least a among Pd, Pt, Ir, Re, Os or the Ru or oxide compound simultaneously is 10～20ppm only, greatly reduces catalyst production cost.The inventor not only has higher activity by the catalyzer that adopts such technical scheme to be surprised to find that to make in addition, conversion of ethylbenzene can be up to 69.8% at 600 ℃, the vinylbenzene yield can reach 67.5%, and B/T (mole) selectivity can reach 0.55, has obtained better technical effect.
The invention will be further elaborated below by embodiment.
Embodiment
[embodiment 1～3]
With 302.1 gram red iron oxides, 60.5 gram iron oxide yellow, 85.8 gram salt of wormwood, 76.6 gram cerous nitrates, 11.9 gram ammonium molybdates, 17.6 gram magnesium oxide, 3.57 ml concns is 10 -3Rh (the NO of mol 3) 2Solution, 10.86 ml concns are 10 -3Pd (the NO of mol 3) 2Solution and 15 gram cement, 10 gram carboxymethyl celluloses stirred in kneading machine 1 hour, add deionized water, mix and stir half an hour again, take out extrusion, be extruded into the particle of 3 millimeters of diameters, 8～10 millimeters of length, put into baking oven, 80 ℃ were dried by the fire 2 hours, 120 ℃ were dried by the fire 2 hours, placed muffle furnace then, made catalyzer in 5 hours in 800 ℃ of roastings.The preparation method of embodiment 2,3 is Rh (NO with embodiment 1 3) 2The add-on of solution is respectively 7.16 milliliters and 8.04 milliliters, Pd (NO 3) 2The add-on of solution is respectively 16.29 milliliters and 21.71 milliliters.
Preparation of Catalyst charging capacity gram is:
Charging capacity, gram
Raw material
Embodiment 1 embodiment 2 embodiment 3
Fe 2O 3 302.1 203.6 129.3
Fe 2O 3·H 2O 60.5 152.4 237.1
K 2CO 3 85.8 200.3 99.5
Ce(NO 3) 3·6H 2O 76.6 126.3 80.7
(NH 4) 6Mo 7O 24·4H 2O?11.9 25.6 10.2
MgO 17.6 30.0 19.8
Cement 15.0 40.0 24.8
Carboxymethyl cellulose 10.0 20.0 9.9
Rh (NO 3) 2Solution (milliliter) 3.57 7.16 8.04
Pd (NO 3) 2Solution (milliliter) 10.86 16.29 21.71
The weight percent of gained catalyzer is composed as follows:
Form embodiment 1 embodiment 2 embodiment 3
Fe 2O 3 71.2 59.3 75.7
K 2O 14.3 23.6 12.4
Ce 2O 3 6.5 8.3 6.1
MoO 3 1.8 3.6 2.0
MgO 6.2 5.2 3.8
Rh 0.0004 0.0008 0.0009
Pd 0.0010 0.0015 0.0020
[comparative example 1～3]
The method for preparing catalyst of comparative example is with embodiment 1.Comparative example 1 does not add precious metal, comparative example 2Rh (NO 3) 2The add-on of solution is 30 milliliters, 3 of comparative examples be that 380 ml concns are 10 -3Pd (the NO of mol 3) 2Solution.Concrete charging capacity is:
Charging capacity, gram
Raw material
Comparative example 1 comparative example 2 comparative examples 3
Fe 2O 3 163.4 264.4 324.7
Fe 2O 3·H 2O 231.4 106.8 62.9
K 2CO 3 99.5 152.0 89.3
Ce(NO 3) 3·6H 2O 88.4 126.7 79.9
(NH 4) 6Mo 7O 24·4H 2O 15.6 8.1 12.3
MgO 30.0 25.3 18.4
Cement 35.0 20.0 25.0
Carboxymethyl cellulose 15.0 10.0 20.0
Rh (NO 3) 2Solution (milliliter)-30.00-
Pd (NO 3) 2Solution (milliliter)--380
The weight percent of gained catalyzer is composed as follows:
Form comparative example 1 comparative example 2 comparative examples 3
Fe 2O 3 73.5 66.4 76.2
K 2O 13.4 18.9 12.1
Ce 2O 3 6.6 8.8 6.0
MoO 3 2.5 1.2 2.0
MgO 4.0 4.7 3.7
Rh - 0.0033 -
Pd - - 0.035
The contrast of table 1 catalyzer dehydrogenation
620℃ 600℃
Catalyzer
Transformation efficiency % selectivity % B/T (mole) transformation efficiency % selectivity % B/T (mole)
Embodiment 1 72.3 93.6 0.17 64.2 94.7 0.37
Embodiment 2 74.5 94.7 0.20 66.6 95.4 0.39
Embodiment 3 77.6 95.4 0.30 69.8 96.8 0.55
Comparative example 1 70.3 93.1 0.15 62.0 94.3 0.34
Comparative example 2 74.7 94.3 0.18 66.8 95.2 0.39
Comparative example 3 75.2 94.9 0.22 67.1 95.5 0.42
From implementation, catalyzer of the present invention, on the basis of Fe-K-Ce-Mo essentially consist, introduce the oxide compound of alkaline-earth metal magnesium and precious metal Rh, the Pd of ppm level, made dehydrogenation catalyst had both had high activity, selectivity, higher B/T (mole) ratio is arranged again, is a kind of high performance catalyst for phenylethylene dehydrogenation.

Claims (10)

1, a kind of dehydrogenation catalyst that is used for preparing styrene from ethylbenzene comprises following active constituent by weight percentage:
A) oxide compound of 40～85% iron is with Fe 2O 3Meter;
B) oxide compound of 8～25% potassium is with K 2The O meter;
C) oxide compound of 3～10% ceriums is with Ce 2O 3Meter;
D) oxide compound of 0.5～5% molybdenum is with MoO 3Meter;
E) metal of 1～20ppm rhodium or oxide compound;
F) 1～100ppm is selected from metal at least a among Pd, Pt, Ir, Re, Os or the Ru or oxide compound;
G) 0.5～10% at least a binding agent that is selected from kaolin, diatomite or the cement.
2, according to the described dehydrogenation catalyst that is used for preparing styrene from ethylbenzene of claim 1, it is characterized in that also containing in the catalyzer alkaline earth metal oxide, its consumption is 0.05～8%.
3,, it is characterized in that alkaline earth metal oxide is a magnesium oxide according to the described dehydrogenation catalyst that is used for preparing styrene from ethylbenzene of claim 2.
4, according to the described dehydrogenation catalyst that is used for preparing styrene from ethylbenzene of claim 1, the oxide compound that it is characterized in that iron is by Fe 2O 3And Fe 2O 3H 2O forms, and its weight ratio is Fe 2O 3: Fe 2O 3H 2O=0.2～5: 1.
5,, it is characterized in that the metal or the oxide compound consumption of rhodium are 1.5～9.5ppm by weight percentage according to the described dehydrogenation catalyst that is used for preparing styrene from ethylbenzene of claim 1.
6,, it is characterized in that the metal or the oxide compound consumption of rhodium are 4～8ppm by weight percentage according to the described dehydrogenation catalyst that is used for preparing styrene from ethylbenzene of claim 5.
7, according to the described dehydrogenation catalyst that is used for preparing styrene from ethylbenzene of claim 1, the consumption that it is characterized in that being selected from metal at least a among Pd, Pt, Ir, Re, Os or the Ru or oxide compound is 1～20ppm by weight percentage.
8, according to the described dehydrogenation catalyst that is used for preparing styrene from ethylbenzene of claim 7, the consumption that it is characterized in that being selected from metal at least a among Pd, Pt, Ir, Re, Os or the Ru or oxide compound is 10～20ppm by weight percentage.
9,, it is characterized in that being selected from metal or oxide compound that at least a metal among Pd, Pt, Ir, Re, Os or the Ru or oxide compound are Pd according to the described dehydrogenation catalyst that is used for preparing styrene from ethylbenzene of claim 1.
10,, it is characterized in that binding agent is a cement according to the described dehydrogenation catalyst that is used for preparing styrene from ethylbenzene of claim 1.
CNB031507174A 2003-09-03 2003-09-03 Dehydrogen catalyst for preparing phenyl ethylene from ethylbenzene Expired - Lifetime CN1302847C (en)

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101279269B (en) * 2007-04-04 2010-10-27 中国石油化工股份有限公司 Low water ratio catalyst for preparing phenylethylene from dehydrogenation of phenylethane
CN101602003B (en) * 2008-06-12 2011-07-20 中国石油化工股份有限公司 Oxide catalyst for preparing styrene by ethylbenzene dehydrogenation
WO2020106447A1 (en) * 2018-11-19 2020-05-28 Clariant International Ltd Dehydrogenation catalysts for converting alkyl aromatic compounds such as ethylbenzene
CN115475628A (en) * 2021-06-16 2022-12-16 中国石油化工股份有限公司 Ethylbenzene dehydrogenation catalyst and preparation method and application thereof

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4804799A (en) * 1987-08-28 1989-02-14 The Dow Chemical Company Dehydrogenation catalyst
JPH04277030A (en) * 1991-03-05 1992-10-02 Nissan Gaadoraa Shokubai Kk Ethylbenzene dehydrogenation catalyst
US6037305A (en) * 1997-03-03 2000-03-14 Rhodia Chimie Use of Ce/Zr mixed oxide phase for the manufacture of styrene by dehydrogenation of ethylbenzene
CA2326538C (en) * 1998-04-01 2007-10-23 Sud-Chemie, Inc. Dehydrogenation catalysts comprising at least iron, alkali metal and a noble metal
US6242379B1 (en) * 1998-04-01 2001-06-05 United Catalysts Inc. Dehydrogenation catalysts

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101279269B (en) * 2007-04-04 2010-10-27 中国石油化工股份有限公司 Low water ratio catalyst for preparing phenylethylene from dehydrogenation of phenylethane
CN101602003B (en) * 2008-06-12 2011-07-20 中国石油化工股份有限公司 Oxide catalyst for preparing styrene by ethylbenzene dehydrogenation
WO2020106447A1 (en) * 2018-11-19 2020-05-28 Clariant International Ltd Dehydrogenation catalysts for converting alkyl aromatic compounds such as ethylbenzene
CN115475628A (en) * 2021-06-16 2022-12-16 中国石油化工股份有限公司 Ethylbenzene dehydrogenation catalyst and preparation method and application thereof
CN115475628B (en) * 2021-06-16 2024-01-30 中国石油化工股份有限公司 Ethylbenzene dehydrogenation catalyst and preparation method and application thereof

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