CN103769150B - The catalyst of low-water ratio ethylbenzene dehydrogenation and method thereof - Google Patents

The catalyst of low-water ratio ethylbenzene dehydrogenation and method thereof Download PDF

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CN103769150B
CN103769150B CN201210412594.8A CN201210412594A CN103769150B CN 103769150 B CN103769150 B CN 103769150B CN 201210412594 A CN201210412594 A CN 201210412594A CN 103769150 B CN103769150 B CN 103769150B
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catalyst
ethylbenzene
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potassium
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CN103769150A (en
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宋磊
危春玲
徐永繁
朱敏
缪长喜
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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

The present invention relates to a kind of catalyst and method thereof of low-water ratio ethylbenzene dehydrogenation, mainly solve potassium easily migration and the loss in ethyl benzene dehydrogenation preparation of styrene course of reaction in the catalyst existed in conventional art, poor catalyst stability, affects the problem in plant running cycle.The technical scheme that the present invention adds part potassium with potassium vanadate form by employing in iron-potassium-cerium-tungsten-magnesium catalyst system and catalyzing solves this problem preferably, can be used in the industrial production of low water than ethyl benzene dehydrogenation preparation of styrene under condition.

Description

The catalyst of low-water ratio ethylbenzene dehydrogenation and method thereof
Technical field
The present invention relates to a kind of catalyst and method thereof of low-water ratio ethylbenzene dehydrogenation preparation of styrene.
Background technology
Ethylbenzene dehydrogenation is strong heat absorption, the reversible reaction increasing molecule.Industrial usual employing inert gas makes diluent to reduce ethylbenzene dividing potential drop, impels reaction to move to product direction.The acting body of water vapour in production of styrene is present:
(1) heat reaction raw materials to temperature required, avoid ethylbenzene to be directly heated to higher temperature, suppress the generation of side reaction;
(2) additional heat, in order to avoid lower the temperature due to endothermic heat of reaction;
(3) reduce ethylbenzene dividing potential drop, impel balance to move to styrene direction;
(4) constantly got rid of the carbon deposit on catalyst by water gas reaction, make catalyst automatic regeneration.
But water vapour addition is subject to reaction system authorized pressure falls the restriction with these two factors of energy consumption.Production of styrene consumes a large amount of water vapours as dehydrogenation medium, energy consumption is large, product condensation number large, process device costly, production cost remains high.Exploitation be applicable to water in isotherm formula fixed bed than the low water lower than 1.6 (weight) than catalyst thus reduce commercial plant operation water than become styrene device, particularly large-scale styrene device in the urgent need to.
The Fe-series catalyst that phenylethylene catalyst is take iron oxide as main active component, potassium oxide is main co-catalyst.Potassium increases the activity of iron oxide with can becoming the order of magnitude, and can promote that carbon deposit is got rid of, made catalyst automatic regeneration by water gas reaction, but potassium easily migration and loss in course of reaction, this is the major reason causing catalysqt deactivation.If general catalyst carries out ethylbenzene dehydrogenation reaction under water ratio (water/ethylbenzene) is lower than 2.0 (weight), water gas reaction slows, and catalyst surface carbon deposit increases, and catalytic activity declines fast.To this, according to related documents report up to now, scientific research personnel had done a lot of trial.After published European patent 0177832 reports the magnesia adding 1.8 ~ 5.4% (weight) in the catalyst, catalyst can show stable premium properties at water under lower than 2.0 (weight), but the potassium content of this catalyst is higher, is greater than 20%.Add with kaliophilite Multiple salts forms as published United States Patent (USP) 4535067 reports a part of potassium in catalyst, but this catalyst 614 ± 2 DEG C time, conversion ratio is less than 65%, selective the highest by 93%, singly can not receive 60%, relatively low, and, do not relate to the life-span of catalyst.
Along with the maximization of styrene device, energy-conservationly seem more and more important.Therefore, small improvement is done to the service condition of dehydrogenation, do not need to change any equipment, do not need to increase investment, obtain huge economic benefit with regard to Neng Shi manufacturing enterprise.Develop and be a kind ofly suitable for low water than the dehydrogenation run under condition, be the direction that researcher makes great efforts always.
Summary of the invention
One of technical problem to be solved by this invention is the catalyst that exists in conventional art in the low water problem poorer than condition stability inferior, there is provided a kind of new ethylbenzene dehydrogenation catalyst with low water ratio, this catalyst is used for ethyl benzene dehydrogenation preparation of styrene reaction and has the low water feature better than condition stability inferior.Two of technical problem to be solved by this invention is to provide a kind of purposes of described catalyst.
For one of solving the problems of the technologies described above, the technical solution used in the present invention is as follows: a kind of ethylbenzene dehydrogenation catalyst with low water ratio, comprises following component by weight percentage:
The Fe of (a) 69 ~ 78% 2o 3;
The K of (b) 5 ~ 9% 2o;
The CeO of (c) 6 ~ 11% 2;
The WO of (d) 0.5 ~ 5% 3;
The MgO of (e) 0.5 ~ 5%;
The V of (f) 2 ~ 5% 2o 5;
The binding agent of (g) 2 ~ 5%;
(h) 0.001 ~ 8% at least one be selected from the oxide of Zn, Sn or Pb;
Wherein 20 ~ 32% of potassium oxide weight consumption derive from potassium vanadate.
In technique scheme, by weight percentage, Fe 2o 3being made up of iron oxide red and iron oxide yellow, its proportioning is Fe 2o 3: Fe 2o 3h 2o=1.0 ~ 3.2:1.By weight percentage, the oxide consumption preferable range that at least one is selected from Zn, Sn or Pb is 0.5 ~ 3%, and more preferably scope is 1 ~ 2.5%.Not containing molybdenum oxide in catalyst.25 ~ 30% of potassium oxide weight consumption derives from potassium vanadate.Binding agent preferred version is be selected from least one in kaolin, diatomite or cement.
For solve the problems of the technologies described above two, the technical solution used in the present invention is as follows: a kind of method of ethylbenzene dehydrogenation, and catalyst wherein used is the described catalyst of one of technical solution problem.
In technique scheme, take ethylbenzene as raw material, reaction condition is: ethylbenzene air speed 0.5 ~ 3.0 hour -1, preferable range is 0.8 ~ 1.5 hour -1; Water/ethylbenzene weight ratio 1.0 ~ 4.0, preferable range is 1.0 ~ 1.6; Reaction temperature 570 ~ 645 DEG C, preferable range is 580 ~ 640 DEG C; Reaction pressure 0 ~ 20KPa, preferable range is 0 ~ 10KPa.
The catalyst component that the present invention relates to raw material used is as follows:
Fe 2o 3added by iron oxide red and iron oxide yellow form; K used is with potash and KVO 3form adds; Ce used adds with cerium oxide, cerium hydroxide or cerium salt form; W used adds with its salt or oxide form; Mg used adds with oxide, hydroxide or magnesium salts form; V used is with KVO 3form adds; Remaining element adds in the form of an oxide.In preparation process of the present invention, except catalyst body composition, also should add perforating agent and binding agent, perforating agent can be selected from graphite, polystyrene microsphere or sodium carboxymethylcellulose, and its addition is 2 ~ 6% of total catalyst weight.Binding agent can be selected from kaolin, diatomite or cement.
Method for preparing catalyst of the present invention is as follows:
By Fe, K, Ce, W, Mg and KVO of weighing by proportioning 3and after other catalytic component that need add and perforating agent, binding agent mix, add the water accounting for catalyst raw material gross weight 15 ~ 35%, mix again, through extrusion, drying, pelletizing becomes diameter 3 millimeters, the particle of long 5 ~ 8 millimeters, in 40 DEG C ~ 70 DEG C dryings, 2 ~ 4 hours, 80 DEG C ~ 150 DEG C dryings 0.5 ~ 4 hour, and then roasting 0.5 ~ 4 hour at 200 DEG C ~ 400 DEG C, roasting 2 ~ 4 hours at 600 DEG C ~ 900 DEG C again, obtains finished catalyst.
Catalyst obtained as stated above carries out activity rating in isotherm formula fixed bed, and for catalyst for preparing phenylethylene from dehydrogenation of ethylbenzene activity rating, process is summarized as follows:
Deionized water and ethylbenzene are inputted preheating mixer through measuring pump respectively, and preheating enters reactor after being mixed into gaseous state, and reactor adopts electric-heating-wire-heating, makes it to reach predetermined temperature.Reactor inside diameter is 1 " stainless steel tube, the catalyst of interior filling 100 milliliters, particle diameter 3 millimeters.After water condensation, with chromatographic, it forms the reactant flowed out by reactor.
Conversion of ethylbenzene, selectivity of styrene calculate as follows:
Conversion of ethylbenzene %=
Selectivity of styrene %=
The present invention adds part potassium with potassium vanadate form by adopting in iron-potassium-cerium-tungsten-magnesium system, significantly improves the stability of potassium, enhance catalyst in course of reaction from power of regeneration, improve catalyst at low water than the stability under condition.The catalyst using the present invention to prepare carries out activity rating at isotherm formula fixed bed, in normal pressure, liquid air speed by common 1.0 hours -1increase by 50% to 1.5 hour -1, 620 DEG C, water checks and rates under reducing by 35% to 1.3 (weight) condition by common 2.0 (weight), run conversion of ethylbenzene after 1000 hours substantially constant, still up to 73.8%, selectivity of styrene remains on 95.1%, achieves good technique effect.
Below by embodiment, the present invention is further elaborated.
Detailed description of the invention
[embodiment 1]
By 320.0 grams of iron oxide reds, 100.0 grams of iron oxide yellows, 50.0 gram potash, 85.0 gram cerium oxalate, 5.0 grams of ammonium tungstates, 13.0 gram magnesia, 38.0 gram potassium vanadate, 2.5 grams of zinc oxide, 2.5 grams of tin oxide, 12.2 grams of cement and 22.0 grams of sodium carboxymethylcelluloses stir 1.5 hours in kneader, add deionized water, mix and stir 0.5 hour, take out extrusion, be extruded into diameter 3 millimeters, the particle of long 5 ~ 8 millimeters, put into baking oven, 60 DEG C are dried 2.5 hours, 130 DEG C are dried 3 hours, then muffle furnace is placed in, in 300 DEG C of roastings 2 hours, 850 DEG C of roastings obtain finished catalyst in 3 hours.
100 milliliters of catalyst are loaded reactors, normal pressure, liquid air speed 1.5 hours -1, 620 DEG C, carry out activity rating under water ratio (weight) 1.3 condition, evaluation result lists in table 2.
[embodiment 2]
By the method Kaolinite Preparation of Catalyst of [embodiment 1], difference is with 200.0 grams of iron oxide reds, 180.0 grams of iron oxide yellows, 33.0 grams of potash, 116.3 grams of cerous nitrates, 8.3 grams of tungsten oxides, 8.0 grams of magnesia, 28.0 grams of potassium vanadates, 11.2 grams of zinc oxide, 22.2 grams of kaolin and 32.5 grams of graphite, and the weight percent composition of gained catalyst lists in table 1.
Carry out activity rating by the appreciation condition of [embodiment 1], evaluation result lists in table 2.
[embodiment 3]
By the method Kaolinite Preparation of Catalyst of [embodiment 1], difference is with 310.0 grams of iron oxide reds, 160.0 grams of iron oxide yellows, 45.2 grams of potash, 75.0 grams of cerous carbonates, 31.2 grams of ammonium tungstates, 20.1 grams of magnesia, 26.2 grams of potassium vanadates, 13.5 grams of tin oxide, 20.8 grams of diatomite and 17.2 grams of polystyrene microspheres, and the weight percent composition of gained catalyst lists in table 1.
Carry out activity rating by the appreciation condition of [embodiment 1], evaluation result lists in table 2.
[embodiment 4]
By the method Kaolinite Preparation of Catalyst of [embodiment 1], difference is with 260.0 grams of iron oxide reds, 140.0 grams of iron oxide yellows, 73.5 grams of potash, 70.0 grams of cerium oxalates, 28.0 grams of ammonium tungstates, 18.0 grams of magnesia, 15.0 grams of potassium vanadates, 5.0 grams of lead oxide, 12.8 grams of diatomite and 20.0 grams of sodium carboxymethylcelluloses, and the weight percent composition of gained catalyst lists in table 1.
Carry out activity rating by the appreciation condition of [embodiment 1], evaluation result lists in table 2.
[embodiment 5]
By the method Kaolinite Preparation of Catalyst of [embodiment 1], difference is with 340.0 grams of iron oxide reds, 120.0 grams of iron oxide yellows, 31.5 grams of potash, 68.2 grams of cerium oxalates, 7.7 grams of ammonium tungstates, 24.0 grams of magnesia, 19.5 grams of potassium vanadates, 6.2 grams of lead oxide, 11.5 grams of cement and 32.5 grams of polystyrene microspheres, and the weight percent composition of gained catalyst lists in table 1.
Carry out activity rating by the appreciation condition of [embodiment 1], evaluation result lists in table 2.
[embodiment 6]
By the method Kaolinite Preparation of Catalyst of [embodiment 1], difference is with 260.0 grams of iron oxide reds, 140.0 grams of iron oxide yellows, 31.5 grams of potash, 85.0 grams of cerium oxalates, 17.9 grams of ammonium tungstates, 4.8 grams of magnesia, 25.7 grams of potassium vanadates, 1.5 grams of zinc oxide, 9 grams of barium monoxide, 11.2 grams of diatomite and 21.0 grams of sodium carboxymethylcelluloses, and the weight percent composition of gained catalyst lists in table 1.
Carry out activity rating by the appreciation condition of [embodiment 1], evaluation result lists in table 2.
[comparative example 1]
By the method Kaolinite Preparation of Catalyst of [embodiment 1], difference does not add potassium vanadate, and the weight percent composition of gained catalyst lists in table 1.
Carry out activity rating by the appreciation condition of [embodiment 1], evaluation result lists in table 2.
[comparative example 2]
By the method Kaolinite Preparation of Catalyst of [embodiment 1], difference does not add potassium vanadate, zinc oxide and tin oxide, and the weight percent composition of gained catalyst lists in table 1.
Carry out activity rating by the appreciation condition of [embodiment 1], evaluation result lists in table 2.
[comparative example 3]
By the method Kaolinite Preparation of Catalyst of [embodiment 1], difference adds 53.0 grams of potassium vanadates, and the weight percent composition of gained catalyst lists in table 1.
Carry out activity rating by the appreciation condition of [embodiment 1], evaluation result lists in table 2.
The weight percent composition of table 1 catalyst
Table 2 catalyst performance contrasts
Above embodiment explanation, adopt in iron-potassium-cerium-tungsten-magnesium catalyst system and catalyzing and add part potassium with potassium vanadate form, catalyst anti-carbon deposition ability obviously strengthens, extend at low water than the service life under condition, there is significant energy-saving effect, can be used in the industrial production of low water than ethyl benzene dehydrogenation preparation of styrene under condition.

Claims (8)

1. a catalyst for low-water ratio ethylbenzene dehydrogenation, comprises following component by weight percentage:
The Fe of (a) 69 ~ 78% 2o 3;
The K of (b) 5 ~ 9% 2o;
The CeO of (c) 6 ~ 11% 2;
The WO of (d) 0.5 ~ 5% 3;
The MgO of (e) 0.5 ~ 5%;
The V of (f) 2 ~ 5% 2o 5;
The binding agent of (g) 2 ~ 5%;
(h) 0.5 ~ 3% at least one be selected from the oxide of Zn, Sn or Pb;
Wherein 20 ~ 32% and vanadic anhydride of potassium oxide weight derive from potassium vanadate.
2. the catalyst of low-water ratio ethylbenzene dehydrogenation according to claim 1, it is characterized in that by weight percentage, the oxide consumption that at least one is selected from Zn, Sn or Pb is 1 ~ 2.5%.
3. the catalyst of low-water ratio ethylbenzene dehydrogenation according to claim 1, is characterized in that in catalyst not containing molybdenum oxide.
4. the catalyst of low-water ratio ethylbenzene dehydrogenation according to claim 1, is characterized in that 25 ~ 30% of potassium oxide weight derive from potassium vanadate.
5. the catalyst of low-water ratio ethylbenzene dehydrogenation according to claim 1, its feature is selected from least one in kaolin, diatomite or cement at described binding agent.
6. a method for ethylbenzene dehydrogenation, is characterized in that catalyst used is the arbitrary described catalyst of Claims 1 to 5.
7. the method for ethylbenzene dehydrogenation according to claim 6, is characterized in that taking ethylbenzene as raw material, ethylbenzene air speed 0.5 ~ 3.0 hour -1, water/ethylbenzene weight ratio 1.0 ~ 1.6, reaction temperature 570 ~ 645 DEG C, reaction pressure 0 ~ 20kPa condition under, raw material and catalyst exposure reaction of styrene.
8. the method for ethylbenzene dehydrogenation according to claim 7, is characterized in that ethylbenzene air speed is 0.8 ~ 1.5 hour -1, water/ethylbenzene weight ratio is 1.0 ~ 1.6, and reaction temperature is 580 ~ 640 DEG C, and reaction pressure is 0 ~ 10kPa.
CN201210412594.8A 2012-10-25 2012-10-25 The catalyst of low-water ratio ethylbenzene dehydrogenation and method thereof Active CN103769150B (en)

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CN106582691B (en) * 2015-10-16 2019-04-12 中国石油化工股份有限公司 Ethylbenzene dehydrogenation catalyst with low water ratio and preparation method thereof
CN106582687B (en) * 2015-10-16 2019-05-14 中国石油化工股份有限公司 Catalyst of low-water ratio ethylbenzene dehydrogenation and preparation method thereof
CN106582690B (en) * 2015-10-16 2019-07-09 中国石油化工股份有限公司 Catalyst for phenylethylene dehydrogenation and preparation method thereof
CN106994353A (en) 2017-04-24 2017-08-01 苏州拓瑞特新材料有限公司 One kind is free of binding agent high intensity ethylbenzene dehydrogenation catalyst with low water ratio

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CN1981930A (en) * 2005-12-14 2007-06-20 中国石油化工股份有限公司 Production of phenylethylene catalyst by low-water ratio ethylbenzene dehydrogenation
CN102343269A (en) * 2010-08-05 2012-02-08 中国石油天然气股份有限公司 Ethylbenzene dehydrogenation catalyst using micron ferric oxide and potassium carbonate as raw materials

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1981930A (en) * 2005-12-14 2007-06-20 中国石油化工股份有限公司 Production of phenylethylene catalyst by low-water ratio ethylbenzene dehydrogenation
CN102343269A (en) * 2010-08-05 2012-02-08 中国石油天然气股份有限公司 Ethylbenzene dehydrogenation catalyst using micron ferric oxide and potassium carbonate as raw materials

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