CN1195583C - Catalyst reactivating method - Google Patents
Catalyst reactivating method Download PDFInfo
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- CN1195583C CN1195583C CNB021331421A CN02133142A CN1195583C CN 1195583 C CN1195583 C CN 1195583C CN B021331421 A CNB021331421 A CN B021331421A CN 02133142 A CN02133142 A CN 02133142A CN 1195583 C CN1195583 C CN 1195583C
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Abstract
The present invention discloses a catalyst regenerating method. A method of calcining oxygen-containing gas is used; catalysts with the same model or similar components after drying and before calcination are mixed in deactivated catalysts, wherein dried catalysts account for 5 to 95% of the total volume of the mixed catalysts; then, the mixed catalysts are segmented, calcined and regenerated. The method of the present invention can effectively control the problem that hot spots are easily generated to burn out the catalysts in the regeneration process of the catalysts; simultaneously, the present invention accelerates the regeneration speed of the catalysts and increases the service performance of the regenerated catalysts or adjusts the service application of the regenerated catalysts. The method of the present invention can be used for the regeneration of deposited and devitalized catalysts of different combustible matter, such as the regeneration of hydrogenation refining catalysts and hydrocracking catalysts.
Description
1, technical field
The present invention relates to a kind of renovation process of decaying catalyst, particularly adopt the method for oxidation burn off carbon deposit method regeneration of deactivated hydrogenation catalyst.
2, background technology
The normal catalysis process that adopts as hydrocracking, hydrofining etc., is handled raw material economically and they is converted into various useful purpose products in oil refining, chemical process.Loss is active gradually in the long-term operation process for the employed catalyzer of these processes, and tracing it to its cause is owing to the deposition of carbon deposit at catalyst surface causes to a great extent.A lot of catalyzer, by the regeneration of burn off carbon deposit, activity can partially or completely be restored, and still can continue to use in industrial production.The catalyzer that the has use of can repeatedly regenerating to reach save energy, increases the purpose of benefit.
Catalyst regeneration is to remove the process that carbon deposit on the catalyzer recovers catalyst activity under oxygen-containing atmosphere.When making charcoal, other material on the catalyzer also will contact with oxygen-containing atmosphere inevitably, as the sulphided state reactive metal on hydrogenation catalyst surface etc., also with oxidized.All said process all will produce a large amount of heat.If heat release is too concentrated, will cause many catalyst properties to change.For hydrogenation catalyst, these variations comprise that the micropore that concentrate relatively in active centre on the catalyzer is sintered, reactive metal is assembled, contained framework of molecular sieve collapses, carrier and intermetallic interaction enhancing etc., and they are conspicuous to the negative impact of catalyst property.
Therefore, the key of regenerative process is that heat release is concentrated and influenced catalyst performance in the time of will preventing material oxidation such as carbon deposit.Existing renovation process is often taked following measure: (1) heat-up rate that slows down, and oxygen level etc. in multistage constant temperature (2) controlled atmosphere, but these methods are more time-consuming.In the existing relevant catalyst regeneration patent, associated viscera is more.Under oxygen containing gas, the method that adopts laser radiation is to the catalyzer decoking as patent USP 5,037,785 suggestions, but this method practicality is little; Patent USP 4,780,195 and USP 4,417,975 grades think that then adding a certain amount of water in atmosphere prevents sintering of catalyst, but this method will cause other problem, for hydrogenation catalyst, will cause nickel aluminium or cobalt aluminate to increase considerably, thereby reduce catalyst activity, and can increase breakage rate.
3, summary of the invention
At the deficiencies in the prior art, the invention provides and a kind ofly can effectively prevent catalyzer sintering in regenerative process, and improve the use properties of regenerated catalyst or adjust the catalyst regeneration process of regeneration rear catalyst purposes.
The inventive method detailed process is as follows:
With decaying catalyst and the dry back of identical or similar composition, the catalyst mix before the roasting, the dry catalyst of sneaking into accounts for and mixes 5～95% of rear catalyst cumulative volume, is preferably 20～80%.With the mixed catalyzer regenerating unit of packing into, with rare gas element device is replaced earlier, oxygen level is progressively increased be 0.5-10.0v% then, be preferably 1.0-5.0v%, catalyzer is carried out the substep coke-burning regeneration.Generally can divide four-stage to regenerate, each stage major control condition is: at 100-140 ℃, constant temperature is 1-3 hour in the time of best 110-120 ℃; At 150-240 ℃, constant temperature is 1-3 hour in the time of best 170-220 ℃; At 250-350 ℃, constant temperature is 1-2 hour in the time of best 260-320 ℃; At 450-550 ℃, constant temperature is 2-4 hour in the time of best 480-510 ℃.
In the preparation process of hydrogenation catalyst, must comprise drying and activation step, the roasting under certain condition of dry sample becomes the reactor of being allowed for access after the oxidation state.Because the metallic salt of the dry sample of hydrogenation catalyst institute load absorbs heat when decomposing, the decaying catalyst of heat release is baking mixed during with regeneration, can slow down decaying catalyst and concentrate heat release, the easier control of temperature during regeneration, and can save recovery time and fund.The regenerated hydrogenation catalyst has suitable selection elasticity in use.If every performance index of regenerated catalyst can reach the minimum requirements of live catalyst, regenerated catalyst still can be used for this technological process so.If there are certain gap in the performance and the live catalyst of regenerated catalyst, then regenerated catalyst is with selected use: to Hydrobon catalyst, may be used for one section reaction process, or be used for other to the slightly inferior technological process of refining effect requirement; For hydrocracking catalyst, then can be used for the production of other purpose product.By in decaying catalyst, sneaking into this method of regeneration behind the dry sample of the trade mark or similar composition, can make things convenient for and the service orientation of purposive control regenerated catalyst, especially bigger to loss of activity regenerated catalyst, this method can replenish with fine catalyst activity undoubtedly.Live catalyst generally exists initial activity higher when using, the problem of carbon deposit easily, and regenerated catalyst often will consider that activity of such catalysts can reach requirement when using.By in decaying catalyst, sneaking into, can address the above problem simultaneously with this method of regeneration behind the trade mark dry sample.
4, embodiment
Catalyzer before the dry back of the inventive method employing, the roasting mixes with decaying catalyst regenerates, and deposits the regeneration of decaying catalyst especially for combustiblematerials.The renovation process of the present invention tangible catalyzer that absorbs heat when being applicable to dry sample roasting is specially adapted to hydrogenation catalyst.Hydrogenation catalyst generally is to comprise the metal of VIB, VIIB, VIII family, or gauge in the bimetal of this scope or many metallic salts be supported on aluminum oxide or (with) other is prepared from as carriers such as silicon oxide, pure aluminium silicate, zeolites.The shape of catalyzer generally is cylindrical, spherical or leafy shape, and diameter is the 0.5-3.5 millimeter, and length is the 1.5-10.0 millimeter.
In the present invention, dry catalyst preferably evenly is blended in the regenerated catalyst, and the catalyst ratio by volume is calculated.Form similar catalyzer refer to main form and content close, can mix the catalyzer of use, as the active metallic content difference, and the close Hydrobon catalyst of function etc.
In the present invention, the contained metallic salt of dry catalyst comprises the materials that are used for hydrogenation catalyst preparation commonly used such as nickelous nitrate (decomposition temperature is 260-330 ℃ during roasting, down together), Xiao Suangu (230-310 ℃), basic nickel carbonate (230-410 ℃), cobaltous dihydroxycarbonate (230-390 ℃), ammonium metawolframate (180-480 ℃), metamolybdic acid ammonium (180-490 ℃), nickel hydroxide (210-280 ℃), cobaltous hydroxide (200-260 ℃).
In the present invention, decaying catalyst is placed in any suitable reactor.Employed atmosphere is except the oxygen level of having indicated, and proportioning gas adopts rare gas elementes such as nitrogen or argon gas, and purity is more than the 99.99v%.
Be described in further detail method of the present invention below by embodiment.
Embodiment 1
A kind of carbon deposit is the MoNi/Al of 5.6w%
2O
3The inactivation Hydrobon catalyst, differential scanning calorimetric (DSC) analytical results of sneaking into similar dry sample front and back sees Table one.
Table one is sneaked into the DSC of dry catalyst front and back decaying catalyst
*The result
| Sneak into the content of dry catalyst, v% | 0 | 25 | 50 | 75 |
| The heat release summit temperature, ℃ | 215 330 517 | 330 517 | 330 | 330 |
| The exothermic peak area, W/g | 0.13 0.65 0.24 | 0.38 0.10 | 0.20 | 0.15 |
*The DSC experiment condition: the catalyst fines about 15mg, the speed with 10 ℃/min in the air atmosphere of 30ml/min heats up.
As can be seen from Table I, sneak into the dry sample heated oxide with the trade mark in the inactivation Hydrobon catalyst, the concentrated exothermic phenomenon on the decaying catalyst when carbon deposit and sulphided state burning can obviously reduce.Along with the increase of mixed volume, this effect is obvious more.
Decaying catalyst and the decaying catalyst of sneaking into dry sample are regenerated under different condition, and the several salient featuress of regeneration condition and regenerated catalyst see Table two.
Table two regeneration condition and regenerated catalyst salient features
| Catalyzer | Decaying catalyst (condition 1) | Decaying catalyst (condition 2) | The dry sample of 75v% decaying catalyst+25v% | The dry sample of 25v% decaying catalyst+75v% |
| Regeneration condition * | 120 ℃ of constant temperature 4h, 200 ℃ of constant temperature 4h, 300 ℃ of constant temperature 3h, 500 ℃ of constant temperature 6h heat-up rates: 120 ℃/h | 120 ℃ of constant temperature 2h, 200 ℃ of constant temperature 2h, 300 ℃ of constant temperature 1.5h, 500 ℃ of constant temperature 3h heat-up rates: 180 ℃/h | 120 ℃ of constant temperature 2h, 200 ℃ of constant temperature 2h, 300 ℃ of constant temperature 1.5h, 500 ℃ of constant temperature 3h heat-up rates: 180 ℃/h | 120 ℃ of constant temperature 1.5h, 200 ℃ of constant temperature 1.5h, 300 ℃ of constant temperature 1h, 500 ℃ of constant temperature 2h heat-up rates: 180 ℃/h |
| The thing phase ** | γ-Al 2O 3 | γ-Al 2O 3β-NiMoO 4 | γ-Al 2O 3 | γ-Al 2O 3 |
| Burn C and lead % *** | 95.9 | 87.8 | 95.2 | 99.1 |
*Regeneration is carried out in the 20ml reactor, and the listed condition, other condition is all identical in table
*Measure with x-ray diffraction method
* *Measure with C, S, H, N elemental analyser
As can be seen from Table II, sneak into the decaying catalyst of the dry sample of 25v% and compare with decaying catalyst (condition 1), the rate of making charcoal is roughly suitable, and constant temperature time only is half of decaying catalyst (condition 1) when regenerating.Decaying catalyst (condition 2) is compared with decaying catalyst (condition 1), because heat-up rate is accelerated, so occurred tangible molybdenum nickel state of aggregation in the thing phase composite, the rate of making charcoal also greatly reduces, though and the decaying catalyst of sneaking into the dry sample of 25v% is the same with decaying catalyst (condition 2) regeneration condition, but owing to sneaked into dry sample, so thing molybdenum nickel state of aggregation do not occur in mutually; After sneaking into the dry sample of 75v%, can in the shorter time, obtain the higher regenerated catalyst of the rate of making charcoal.
According to the Performance Analysis of regenerated catalyst, the regeneration sample use value of decaying catalyst (condition 2) may be little; Decaying catalyst (condition 1) can be used for the first stage reactor for the treatment of process; The regenerated catalyzer then can substitute live catalyst after sneaking into dry sample.
Embodiment 2
The physico-chemical property of the fresh Hydrobon catalyst (B) of a kind of regeneration Hydrobon catalyst (A) and another kind of roasting sees Table three.
The physical and chemical performance of two kinds of Hydrobon catalysts of table three relatively
| Physical and chemical indexes | A | B |
| Chemical constitution MoO 3，w％ NiO，w％ P 2O 5W% C, w% S, other character specific surface of w%, mm 2Pore volume, ml/g mean pore size, nm intensity, N/mm | 24.5 4.1 - 0.25 0.4 185 0.223 6.8 22 | 24.5 4.1 1.3 - - 195 0.240 7.0 22 |
| Purposes | Wax oil hydrogenation is refining | Wax oil hydrogenation is refining |
As can be seen from Table III, above-mentioned two kinds of catalyzer are similar on physico-chemical property.To the decaying catalyst (carbon deposit is 6.6w%) of A when regenerating, sneak into the dry sample of B, and copy embodiment 1 to carry out dsc analysis and the sample that under the same conditions the dry sample by the decaying catalyst of A and B mixed is regenerated and characterized, experimental result is close with embodiment 1.
Embodiment 3
A kind of carbon deposit is the MoNi/USY+Al of 4.8w%
2O
3Deactivated commercial hydrocracking catalysts, differential scanning calorimetric (DSC) analytical results of sneaking into similar dry sample front and back sees Table four.
Table four is sneaked into the DSC of dry catalyst front and back decaying catalyst
*The result
| Sneak into the content of dry catalyst, V% | 0 | 25 | 50 | 75 |
| The heat release summit temperature, ℃ | 185 290 493 | 290 493 | 290 | 290 |
| The exothermic peak area, W/g | 0.04 0.35 0.12 | 0.17 0.02 | 0.05 | 0.02 |
*The DSC experiment condition is the catalyst fines about 15mg, and the speed with 10 ℃/min in the air atmosphere of 30ml/min heats up.
As can be seen from Table IV, sneak into the dry sample post-heating oxidation with the trade mark in deactivated commercial hydrocracking catalysts, the concentrated exothermic phenomenon on the decaying catalyst when carbon deposit and sulphided state burning can obviously reduce.Along with the increase of mixed volume, this effect is obvious more.
Decaying catalyst and the decaying catalyst of sneaking into dry sample are regenerated under different condition, and the several salient featuress of regeneration condition and regenerated catalyst see Table five.
Table five regeneration condition and regenerated catalyst salient features
| Catalyzer | Decaying catalyst (condition 1) | Decaying catalyst (condition 2) | The dry sample of 75V% decaying catalyst+25V% | The dry sample of 25V% decaying catalyst+75V% |
| Regeneration condition * | 120 ℃ of constant temperature 4h, 170 ℃ of constant temperature 4h, 260 ℃ of constant temperature 3h, 480 ℃ of constant temperature 6h heat-up rates: 120 ℃/h | 120 ℃ of constant temperature 2h, 170 ℃ of constant temperature 2h, 260 ℃ of constant temperature 1.5h, 480 ℃ of constant temperature 3h heat-up rates: 180 ℃/h | 120 ℃ of constant temperature 2h, 170 ℃ of constant temperature 2h, 260 ℃ of constant temperature 1.5h, 480 ℃ of constant temperature 3h heat-up rates: 180 ℃/h | 120 ℃ of constant temperature 1.5h, 170 ℃ of constant temperature 1.5h, 260 ℃ of constant temperature 1h, 480 ℃ of constant temperature 2h heat-up rates: 180 ℃/h |
| The thing phase ** | USY γ-Al 2O 3 | USY γ-Al 2O 3β-NiMoO 4 | USY γ-Al 2O 3 | USY γ-Al 2O 3 |
| Burn C and lead % *** | 91.5 | 86.9 | 90.1 | 99.3 |
| USY degree of crystallinity, % ** | 100 | 88 | 110 | 126 |
*Regeneration is carried out in the 20ml reactor, and the listed condition, other condition is all identical in table
*Measure with x-ray diffraction method
* *Measure with C, S, H, N elemental analyser
As can be seen from Table V, sneak into the decaying catalyst of the dry sample of 25w% and compare with decaying catalyst (condition 1), the rate of making charcoal is suitable, but the degree of crystallinity of USY is higher, and constant temperature time only is half of decaying catalyst (condition 1) when regenerating; Decaying catalyst (condition 2) is compared with decaying catalyst (condition 1), because heat-up rate is accelerated, so occurred tangible molybdenum nickel state of aggregation in the thing phase composite, the rate of making charcoal also greatly reduces the USY skeleton and destroys serious; Though and the decaying catalyst of sneaking into the dry sample of 25w% is the same with decaying catalyst (condition 2) regeneration condition, owing to sneaked into dry sample, so thing molybdenum nickel state of aggregation do not occur in mutually, the ruined degree of USY skeleton reduces simultaneously; After sneaking into the dry sample of 75w%, can obtain the higher regenerated catalyst of the rate of making charcoal in the shorter time, the ruined degree of USY skeleton obviously reduces.
Claims (6)
1, a kind of catalyst regeneration process adopts oxygen-containing gas roasting regeneration method, it is characterized in that decaying catalyst is mixed with dry back, the roasting procatalyst of identical or similar composition, and the dry catalyst of sneaking into accounts for and mixes 5～95% of rear catalyst cumulative volume; Wherein the oxygen level of oxygen-containing gas is 0.5-10.0v%, regenerative process in four stages: at 100-140 ℃ of constant temperature 1-3 hour, at 150-240 ℃ of constant temperature 1-3 hour, at 250-350 ℃ of constant temperature 1-2 hour, at 450-550 ℃ of constant temperature 2-4 hour.
2,, it is characterized in that described dry catalyst accounts for 20～80% of mixing rear catalyst cumulative volume according to the described catalyst regeneration process of claim 1.
3, according to the described catalyst regeneration process of claim 1, it is characterized in that described first section regeneration temperature is 110-120 ℃, second section regeneration temperature is 170-220 ℃, and the 3rd section regeneration temperature is 260-320 ℃, and the 4th section regeneration temperature is 480-510 ℃.
4,, it is characterized in that described catalyzer is a hydrogenation catalyst according to the described catalyst regeneration process of claim 1.
5,, it is characterized in that described hydrogenation catalyst is Hydrobon catalyst or hydrocracking catalyst according to the described catalyst regeneration process of claim 4.
6,, it is characterized in that the catalyzer before described regenerated catalyst and dry back, the roasting carries out uniform mixing according to the described catalyst regeneration process of claim 1.
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| CNB021331421A CN1195583C (en) | 2002-10-10 | 2002-10-10 | Catalyst reactivating method |
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| CNB021331421A CN1195583C (en) | 2002-10-10 | 2002-10-10 | Catalyst reactivating method |
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| CN1195583C true CN1195583C (en) | 2005-04-06 |
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Families Citing this family (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100340340C (en) * | 2004-10-29 | 2007-10-03 | 中国石油化工股份有限公司 | Carbon deposit cleaning agent and its application in reproduction process of deactivation catalyst |
| CN100340341C (en) * | 2004-10-29 | 2007-10-03 | 中国石油化工股份有限公司 | Carbon deposit cleaning agent and its application in reproduction process of deactivation catalyst thereof |
| CN100360238C (en) * | 2004-10-29 | 2008-01-09 | 中国石油化工股份有限公司 | Method for reproducing deactivation catalyst of carbon deposit |
| CN100363469C (en) * | 2004-11-30 | 2008-01-23 | 中国石油化工股份有限公司 | Regenerating method for hydrogenating catalyst |
| CN101618354B (en) * | 2008-07-04 | 2011-05-18 | 中国石油化工股份有限公司 | Method for regenerating and revivifying hydrogenation catalyst |
| CN101992131B (en) * | 2009-08-27 | 2013-03-06 | 中国石油化工股份有限公司 | Method for regenerating hydrogenation catalyst, regenerated hydrogenation catalyst and application thereof |
| CN102463153B (en) * | 2010-11-04 | 2014-07-23 | 中国石油化工股份有限公司 | Regeneration and reactivation method for carbon deposition inactivation catalyst |
| CN102836743B (en) * | 2011-06-20 | 2014-11-05 | 中国石油化工股份有限公司 | Regeneration method of molecular sieve catalyst |
| CN106669788B (en) * | 2015-11-11 | 2019-07-12 | 中国石油化工股份有限公司 | The preparation method of hydrocracking catalyst |
| CN106378129B (en) * | 2016-09-30 | 2018-11-06 | 中国科学院福建物质结构研究所 | The method for removing Pd catalyst surface carbon deposits using dual whole low temperature reaction |
| CN107126976B (en) * | 2017-04-25 | 2021-11-16 | 广东新华粤树脂科技有限公司 | Steam purging-hydrogen hot gas stripping combined regeneration method for cracking carbon nine hydrogenation catalyst |
| CN111097514B (en) * | 2018-10-29 | 2022-03-08 | 中国石油化工股份有限公司 | Method for restoring activity of low-activity hydrogenation modified pour point depressing catalyst |
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2002
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