CN1053256A - Use the middle runnings hydrocracking catalyst of low acidity Y zeolite - Google Patents
Use the middle runnings hydrocracking catalyst of low acidity Y zeolite Download PDFInfo
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Abstract
The invention discloses a kind of high-selective and hydrogenating cracking catalyst that can increase intermediate distillate yied.
This catalyzer contains hydrogen y-type zeolite, a kind of metal hydrogenation component and the refractory oxides carrier substance that a kind of unit cell dimension is about 24.20-24.40 .This catalyzer be characterized as temperature programmed desorption(TPD) (TPD) acidity value with low ammonia.This can finish by the dehydroxylation that dried roasting causes.
Description
The present invention relates to a kind of middle runnings hydrocracking catalyst of highly selective.More particularly, the present invention relates to a kind of catalytic hydrocracking method that boiling range is the middle runnings of 300 to 700 (149～370 ℃) that changes into the heavy hydrocarbon oil highly selective.The invention is characterized in and used a kind of novel low acidity Y zeolite.
Hydrocracking is a kind of refining of petroleum method, and it is in the presence of hydrogen, and the molecular moiety of hydrocarbonaceous material is decomposed to obtain the hydrocarbon product of desired lower molecular weight.Because the requirement to middle cut (for example rocket engine fuel and diesel oil fuel) increases, so the industrial significance of hydrocracking strengthens, because it is less that this method makes charging generate the amount of gas and coke, thereby obtain the product liquid of the middle runnings boiling range of higher proportion than thermally splitting or non-consumption hydrogen cracking method.
The key factor of competitive method for hydrogen cracking is to use has highly active special catalyst to cracking and hydrogenation.As everyone knows, many such dual-function catalysts are arranged in the prior art.Generally, cracking activity (being the tolerance that feedstock conversion becomes product) is considered to be caused by the solid acid component that is present in the catalyst substrates usually.On the other hand, hydrogenation activity belongs to the various metals that are deposited on the catalyst substrates usually.These metals are selected from VI B and the VIII family in the periodic table of elements usually.
Be used for hydrocracking industry and contain the VI B family that is selected from the periodic table of elements and the metal and/or the metallic compound of VIII family with the general catalyzer of production middle runnings, this metal or metallic compound are deposited on amorphous heat-resistant inorganic oxide matrix material, on the mixture as silica-alumina.In recent years, noticeable industrial activity is directly exploitation contains crystal aluminosilicate in catalyst matrix a hydrocracking catalyst.
Generally, zeolite aluminosilicate has higher total acidity than amorphous oxide, therefore shows higher cracking activity.Because this specific character it is believed that zeolite provides good katalysis in the hydrocarbon conversion.In the research of exploitation zeolite hydrocracking catalyst, what pay special attention to is as far back as United States Patent (USP) 3,130, disclosed y-type zeolite in 007.The catalytic mechanism of y-type zeolite also imperfectly understands.Yet, to observe, the hydrocracking catalyst that contains y-type zeolite not only shows the high reactivity to production middle runnings, and desired middle runnings product is also had good selectivity.
The hydrocracking catalyst that contains zeolite in the prior art contains the y-type zeolite in heat-resistant inorganic oxide matrix or the y-type zeolite of various modifications.For example, mol ratio that y-type zeolite can be by increasing silicon oxide and aluminum oxide and minimizing unit cell dimension come in addition modification.
The United States Patent (USP) 4 that J.W.Ward obtains, 419,271 disclose a kind of hydrocarbon conversion catalyst that is used for hydrocracking, this catalyzer contains one or more and is loaded in hydrogenation component on the matrix, said matrix contains the crystal silicon-aluminate zeolite that hydro carbons is had cracking activity, and silica-alumina is scattered in the alumina host.This patentee points out, in order to make the zeolite with required cracking activity, needs to replace basic metal with multivalent metal cation, hydrogen ion or hydrogen ion precursor, and its replacement is finished with ion exchange method usually.Be reduced to alkali metal content less than 5%(heavy), preferably heavy less than 0.5%() (by alkalimetal oxide calculating) obtain the material of remarkable cracking activity.This patentee points out that in hydrocracking catalyst composition, the best zeolite that is used as active ingredient is the y-type zeolite of modification, and the silicon oxide of this y-type zeolite is about 3.5-6.0 with the ratio of aluminum oxide, and surface-area is about 500～700m
2/ g, unit cell dimension is about 24.25～24.35
, that the similar sodium Y zeolite of the ratio of aluminum oxide is compared the water adsorptive power is heavy less than 8%(by zeolite weight with silicon oxide) and (under 4.6mm steam partial pressure and 25 ℃), and ion-exchange capacity is less than 20%.
The United States Patent (USP) 4 that R.D.Bezman and J.A.Rabo obtain, 401,556 disclose a kind of hydrocarbon conversion catalyst that contains super-hydrophobic Y type zeolite (UHP-Y), the feature of this zeolite is that the mol ratio of silicon oxide and aluminum oxide is 4.5～35, basically be the X-ray powder diffraction spectrogram of Y zeolite, ion-exchange capacity is not more than 0.07, and unit cell dimension is 24.20～24.45
, surface-area is 350m at least
2/ g(B-E-T), at 25 ℃ and P/P
0Be that water vapor adsorption ability under 0.1 the situation is heavy less than 5.00%(), and residual butanols test (Residual Butanol Test) value is not more than 0.40%(heavily).
The United States Patent (USP) 4 that J.W.Ward obtains, 517,073 discloses a kind of hydrocracking catalyst that is stated from the active hydrogenation component on the carrier that contains, and the mol ratio that said carrier contains dispersive silica-alumina and silicon oxide and aluminum oxide in aluminum oxide is approximately greater than 6.0 y-type zeolite.In this patentee's method for hydrogen cracking will with catalyzer in used zeolite have the basic crystalline structure of y-type zeolite, contain less than 1.5%(heavy) basic metal (calculating) with total metal monooxide, and unit cell dimension generally is equal to or less than 24.65
The mol ratio of silicon oxide and aluminum oxide is 6～20 preferably, in this mol ratio less than 20 o'clock, the zeolite that this patentee will use is at 25 ℃, 4.6mmHg the water vapor adsorption ability under the steam partial pressure is at least 20%(and weighs) (in anhydrous zeolite weight), and, under 100mmHg and-183 ℃ the most aerobic adsorptive power to be at least 25%(heavy).
Above-mentioned patent description contain the situation of the hydrocracking catalyst of y-type zeolite in the prior art.The y-type zeolite of mentioning in the prior art that is used for hydrocracking is with following several terms, and promptly silicon oxide and alumina molar ratio, unit cell dimension, ion-exchange capacity, surface-area and water adsorptive power characterize.The dual-function catalyst that is used for hydrocracking provides cracking and hydrogenation activity.As everyone knows, in the prior art, the acidity of catalyst component will influence the cracking activity of catalyzer.For example, the paper of Dwyer cited below and Newsam has been discussed the reason and the influence of the acidity of zeolite.Up to the present, although the skilled researchist in hydrocracking field has carried out great effort, directly relevant with the acidity of cracking component (as y-type zeolite) hydroxyl concentration is disregarded optionally influencing in fact to be left in the basket.
Generally, dehydroxylation is not discussed in the literature.To this a exception is to comprise that United States Patent (USP) 4,790,928 that people such as C.D.Chang obtains is at interior serial reference document.This reference relates to the performance of improving ZSM-5 and other medium pore volume zeolite by dehydroxylation optionally.It is pointed out behind the zeolite synthesis catalyzer that obtains, and can be used for the catalytic dewaxing of petroleum fractions ballast oil as usual or vacuum gas oil.Roasting can cause dehydroxylation under 600 ℃ of (1172) anhydrous situations being higher than.
The 140th～147 page of " American Chemical Society's monograph " 171 phase that Jule A.Rabo edits, relevant for the research discussion of the influence of the hydroxy radical content of y-type zeolite and roasting.
The service condition of the low acidity catalyzer of hydrocracking has been discussed in people's such as N.Y.Chen United States Patent (USP) 4,263,129.But it is believed that the document is confined to use resembles ratio with silicon oxide and aluminum oxide greater than the zeolite 12 the ZSM-5.Though steam treatment can reduce acidity, obtain high sodium content and obtain low acidity thereby preferably zeolite and sodium or other basic metal are carried out large-scale ion-exchange.The difference of method of the present invention and this document is with low sodium content, the low silica y-type zeolite with the ratio of aluminum oxide.
The United States Patent (USP) 3,929,672 of J.W.Ward has compared steam treatment and the dried roasting influence to y-type zeolite.And point out that dried roasting causes degree of crystallinity to reduce.
Put it briefly, the invention provides the middle runnings selective hydrocracking method that a kind of use contains the catalyzer of crystallization hydrogen y-type zeolite, the unit cell dimension of said hydrogen y-type zeolite is about 24.20～24.40
, and have the surface hydroxyl of enough low levelss so that NH
3-TPD acidity value is approximately less than 2.00.The most handy dried roasting dehydroxylation of this zeolite.
Feature of the present invention can be the hydrocracking catalyst of production middle runnings optionally, and this catalyzer comprises following component: (1), a kind of hydrogenation component, (2), a kind of salic heat-resistant inorganic oxide matrix and (3), a kind of unit cell dimension are 24.20～24.40
And NH
3-TPD acidity value is less than 1.50 crystallization hydrogen Y type aluminosilicate zeolite.
An object of the present invention is to provide improved hydrocracking catalyst and method for hydrogen cracking.Another object of the present invention provides a kind of presenting to be increased active and improved hydrocracking catalyst optionally to middle cut product.
Have been found that now the hydrogen y-type zeolite that has a lower concentration bonded hydroxy at zeolite surface provides a kind of good hydrocracking catalyst.Find that also (it can use the temperature programmed desorption(TPD) (NH of ammonia to this catalyzer
3-TPD) characterize) very high selectivity is arranged in the method for hydrogen cracking of cut between aborning.
Hydrocracking composition of the present invention contains a kind of crystallization y-type zeolite.This y-type zeolite is generally at United States Patent (USP) 3,130, and is open in 007.Classify reference as in this this patent.
The chemical formula of the Y-zeolite that reaches with the oxide molar numerical table can be written as:
0.9±0.2Na
2O∶Al
2O
3∶WSiO
2∶XH
2O
Wherein W be 3～about 6, X can be the numerical value up to 9.
The standard construction of y-type zeolite is the crosslinked SiO of Sauerstoffatom by sharing
4And AlO
4Tetrahedral three-dimensional framework structure.For example metal ion, rare earth ion, alkalimetal ion, ammonium ion, amine complex and hydrogen ion make it balance to aluminiferous tetrahedral electricity price by the positively charged ion that exists.Void space in the skeleton can be full of by water molecules.Usually, crystalline zeolite self exists or makes alkali metal form.Material resemble the y-type zeolite is to classify based on above-mentioned chemical formula and by the known X-ray diffraction spectrogram that material presents.Y-type zeolite can contain germanium, gallium, phosphorus or boron in its structure, these elements or with traditional silicon oxide and aluminum oxide coexistence or replace traditional silicon oxide and aluminum oxide.
" acidity " of zeolite has been the problem of important research and conjecture.For example acidity is formed in the paper that pass with strength of acid ties up to the John Dwyer on " chemical industrie " published on April 2nd, 1984 the 258th page the influence of catalyst activity and zeolite and is discussed.The evidence that this paper proposes points out that the hydroxyl in the zeolite channels provides Bronsted (Bronsted) active centre.And two types hydroxyl described: surface hydroxyl or terminal hydroxyl and the bridging hydroxyl in macropore.Extensive discussions be acidity, composition, catalyst activity and catalyst selectivity.The feature that should be noted that selectivity of product is by the geometrical shape in hole and size and to the ultimate influence decision in the active centre, inside that is diffused into selection, rather than by the acidity decision or influenced by acidity.
Having stated in one piece of paper delivering on " science " that J.M.Newsam published on March 7th, 1986 (1093 pages of 231 volumes) that the great majority reaction that comprises in catalytic cracking relates to is being positioned at the acid sites of zeolite.Above-mentioned broensted acidity is mainly caused by the bridging hydroxyl.Think this acid sites be determine by the protonated tetrahedral aluminium in rich silicon oxide zeolite framework or cause.
As illustrated by the data of listing below, have been found that HY type zeolite is directly relevant with the strength of acid of zeolite to production middle runnings product selectivity, it also is the hydroxyl concentration of not considering in the zeolite.It all is novel it is believed that the application of so low hydroxyl zeolite hydrocracking catalyst composition and forming.
Because can not directly measure hydroxyl concentration at present, therefore this measurement must be carried out indirectly.The analytical procedure of selecting is to measure the acidity of zeolite.This just thinks directly relevant with hydroxyl concentration.
Temperature programmed desorption(TPD) (the NH of ammonia
3-TPD) be widely used, and be considered to a kind of effective ways of measuring zeolite acidity.(referring to Hidalgo, people's such as C.V. article " measuring the acidity of various zeolites with the temperature programmed desorption(TPD) of ammonia ", catalysis magazine, 85 volume the 362nd～369 page of No.2 (1984).This literary composition is classified reference as at this).Ammonia is a kind of fabulous molecular detection of TPD method.This molecular volume has good especially micropore permeation ability for a short time, and its strong basicity can make it stable rapidly on acid sites.The TPD method is good method, because it is fairly simple, the time of consumption is the shortest, and can repeat exactly.
At this used NH
3-TPD method comprises 0.250 ± 0.001 gram zeolite sample pretreatment, i.e. at first heating 75 minutes in the air of 500 ℃ and 60cc/min flow velocity, heating 15 minutes in the helium of 500 ℃ and 60cc/min flow velocity then.Then with pretreated zeolite in about 20 minutes under helium-atmosphere cool to room temperature.In order to guarantee balance, then with the zeolite sample with saturated 5 times of branch ammonias (condition of normal pressure) such as 10cc.Then saturated zeolite was at room temperature purged 35 minutes with the helium of 60cc/min flow velocity.After this cycle, immediately this air-flow is directly entered gas-chromatography, simultaneously with the temperature programming speed heating of sample, up to 650 ℃ of top temperatures with 8.33 ℃/min.Under 25～500 ℃ temperature, the desorption of ammonia was monitored 75 minutes with register then.
Relevant by the desorption area under a curve that gas chromatograph draws with the total amount of the ammonia of desorption.The mass spectroscopy of exit gas shows the desorption that can ignore impurity in 25～500 ℃ of temperature ranges.In order to make the desorption log normalization, the ammonia of desorption is collected in 10%H
2SO
4In the solution and quantitative with prior art.The ammonia amount that is determined at the per unit area desorption under the desorption curve is 0.038 ± 0.004 mmole/unit surface.
Desorption curvilinear integral between 25～500 ℃ is determined NH
3-TPD acidity value.Then area under a curve be multiply by coefficient 0.038 mmole/unit surface, divided by the weight (0.250 gram) of sample, obtain NH again
3-TPD acidity value, unit are mmole/grams.For example, if the total unit surface of the integration between 25～500 ℃ is 10.0, NH then
3-TPD acidity value will be calculated as 10 unit surfaces * 0.038 mmole NH
3/ unit surface/0.250 gram sample=1.52 mmoles/gram sample.
All NH of the present invention's imagination
3-TPD acidity value all has mmole/this fundamental unit of gram sample.For the sake of simplicity, NH described here
3-TPD value is the unit of marking not all.By NH
3-TPD repeats the acidity data need accurately repeat several Key Experiment parameters, as heat-up rate, sample size, gas flow and equilibrium temperature.Therefore, it usually is difficult the acidity that obtains with different methods being compared.In any case the acidity value that should understand the present invention's imagination not only comprises the above-mentioned NH of using
3Those values that-TPD measures, and comprise those matter of equal value of using other method to obtain to same sample.
The ratio of skeleton silicon oxide and aluminum oxide of y-type zeolite that is applicable to present method is less than 6.0.
The present invention expects that the unit cell dimension offer of the y-type zeolite that uses is 24.20-24.45
, the zeolite unit cell dimension will be 24.20-24.40 preferably
, preferably be about 24.30
It should be noted that,, think irrelevant with this parameter of acidity though the hydrocracking catalyst that prior art openly contains zeolite may be very sensitive to the variation of zeolite unit cell dimension.Along with the reduction acidity of unit cell dimension reduces is because the aluminium content of zeolite reduces, and this result is irrelevant with the different acidity measurement of the zeolite of ratio that identical silicon oxide and aluminum oxide are arranged and/or unit cell dimension.
The y-type zeolite of the present invention expectation should have approximately the NH less than 2.00
3-TPD acidity value.Better be acidity value approximately less than 1.50, better below 1.50, preferably about 0.1～0.70.
Think that the actual path of the hydrogen y-type zeolite that to reduce acidity is not crucial to the present invention.Therefore, the hydrocracking catalyst of expectation can be used in United States Patent (USP) 3,130, and any initial substance of the y-type zeolite with basic X-ray powder diffraction spectrogram described in 007 prepares.Initial substance can improve with the technology that the known any acidity of the prior art that obtains required h-type zeolite reduces.Therefore, resemble hydrothermal treatment consists at high temperature, roasting, dipping or with the improvement technology such as arbitrary combination of the reaction of acidity inhibitory substance, crystallization and these methods all be desired.
Think that for purposes of the invention prepare zeolite and improved method are not main.Any hydrogen y-type zeolite with suitable low hydroxyl concentration all can be used as the zeolite component of hydrocracking catalyst of the present invention.
The method that a kind of acidity reduces is hydrothermal treatment consists more than 500 ℃ at least 0.5 hour.The better method that reduces acidity is roasting at least 0.5 hour in dry air more than 500 ℃.The best method that reaches desired dehydroxylation is under anhydrous basically situation zeolite to be kept more than 704 ℃ 1 hour in temperature at least at least.The use of this special adaptations technology is not thought unique for purposes of the invention.Expection has 2 kinds or multiple different improvement technology to use.
It is heavy that hydrocracking catalyst composition of the present invention should contain 2～20%(), best 2～10%(is heavy) y-type zeolite of the present invention.The 2-98%(that composition of the present invention also contains a kind of carrier that can form the finished product catalyst composition is heavy), best 5～95%(is heavy) the porous heat-resistant inorganic oxide matrix.This matrix can contain any known heat-resistant inorganic oxide such as aluminum oxide, magnesium oxide, silicon oxide, titanium oxide, zirconium white, silica-alumina or the like and their mixture.
Matrix comprises silica-alumina or aluminum oxide preferably.Best matrix comprises the mixture of silica-alumina and aluminum oxide, and 45～90%(that wherein said silica-alumina content accounts for said matrix is heavy).It is heavy to contain 5～45%(approximately) carrier of aluminum oxide also is preferably.
The silica-alumina component can use that one of reasonable several different methods prepares in the prior art relevant with it.These methods comprise the acid treatment of natural clay or sand, by water-sol co-precipitation or phase postprecipitation.These methods usually combine with one or more activation treatment, and these activation treatment comprise that deep fat is aging, steam treatment, drying, oxidation, reduction, roasting etc.Usually the pore structure of the carrier that defines with surface-area, aperture and pore volume can be improved to the scope of regulation with any appropriate means, these methods are included under control acidity or the alkaline condition, the aging water-sol and/or hydrogel under room temperature or comparatively high temps, or under critical pH value gelling carrier or with various inorganic or organic agent treated carriers.
The finished catalyst offer that is applicable to method for hydrogen cracking has 200～700 meters
2The surface-area of/gram has 20～300 approximately
The aperture, have approximately 0.10～0.80 milliliter/gram the pore volume peace treaty 0.50～0.90 gram per centimeter is arranged
3Apparent bulk density.Preferably there are 350 meters
2The surface-area that/gram is above.
The alumina component of catalyzer can be any hydrated aluminum oxide or alumina gel, for example have boehmite structure Alpha-alumina-hydrate, have the Alpha-alumina trihydrate of gibbsite structure, beta-alumina trihydrate with Bayer structure, or the like.A kind of good especially aluminum oxide is called Ziegler (Ziegler) aluminum oxide, and it is at United States Patent (USP) 3,852, the existing introduction in 190 and 4,012,313, it is at the United States Patent (USP) 2,892 of Ziegler, in the Ziegler higher alcohols building-up reactions described in 858 as a kind of by product.Best aluminum oxide can have been bought from Conoco Chemical Division of Continental Oil ComPany at present, and its trade mark is " Catapal ".This material is a kind of Alpha-alumina-hydrate (boehmite) of extreme high purity, proved its roasting at high temperature after, obtain high purity r-aluminum oxide.
Certainly the accurate physical properties of carrier material such as shape and surface-area do not limit within the scope of the invention.For example, catalyzer can sheet, the form of ball, particle, fragment, ball or various specified shape (for example trilobal extrusion) exists, and such catalyzer is arranged in the bed that fixes in the conversion zone.On the other hand, catalyzer can be made into the suitable shape that is used for the moving bed reaction section, in this moving bed reaction section, hydrocarbon feed and catalyzer or adverse current or and stream pass through; Or in the fluidized solids method, raw material upwards passes through the turbulent bed of catalyzer in small, broken bits; Or in suspension method, catalyzer becomes slurry in raw material, and the mixture that forms is sent to conversion zone.Raw material can upwards flow or flow downward and pass through reactor with liquid, steam or mixed phase.
Granules of catalyst can comprise that well-known forming oil column method and pressing method prepare with any method well known in the prior art.In the forming oil column method, can be at first the zeolite powder of selecting be suspended in the suitable colloidal sol and prepares granules of catalyst.Active metal component also can join in the colloidal sol.Collosol intermixture can be fed with droplet form then and remain in the oil bath of certain temperature, and rest in the oil bath till the colloidal sol droplet is frozen into gel ball.Then this spherical particle is taken out from oil bath, the appropriate time that wears out under the condition that improves temperature in suspension medium then then can be with spherical particle drying and roasting.Aluminum oxide or silica-alumina matrix of oxide if desired, then the oil column method can be respectively according to United States Patent (USP) 2,620, and 314 or 3,003,972 finish, and classify reference as at this this two pieces of documents.
The better method that the present invention prepares catalyst composition is to grind the zeolite of aluminum oxide and amorphous silicon oxide-aluminum oxide and selection simultaneously altogether.Before mixing, preferably be broken into the blended component Powdered.During this time also active metal component can be joined in this mixture.After grinding, mixture by the die head of suitable opening such as circle or cloverleaf pattern opening is arranged, is obtained the material of desired shape.It is long to be cut into 1/2～1/4 inch to this extrudate, then drying and roasting under high temperature and the known condition of prior art.
Although hydrogenation component can before forming oil column or the extrusion method or during add, zeolite and the heat-resistant inorganic oxide matter that is preferably in selection is shaped, with pickling process hydrogenation component is cooperated with catalyzer after drying and the roasting.The dipping of metal hydrogenation component in these particles can comprise that evaporation dipping, immersion are flooded, the decompression dipping technique is finished with any method well known in the prior art.Generally, dry and baked particle can contact with one or more solution that contains the required hydrogenation component that is solubilized form.Behind the contact appropriate time, composition grain drying and roasting are obtained the finished catalyst particle.The other guidance for preparing suitable catalyzer can be by comprising United States Patent (USP) 4,588,496 and 4,600,498(classifies reference as at this) in interior many reference, obtain, in these documents relevant for preparation with use the introduction of the hydrogenation catalyst contain Y zeolite.
The hydrogenation component of expectation is those catalytic active component that are selected from VI B family and VIII family metal and their compound.Generally, the amount of the hydrogenation component in the finished catalyst composition is lacked than other above-mentioned amount with its blended component.By element, containing VIII family component usually, to be about 0.1～30%(heavy in the weight of finished catalyst composition), preferably about 1～15%(is heavy), it is heavy to contain the about 0.05～30%(of VI B family component), preferably about 0.5～15%(is heavy).Desired hydrogenation component comprises one or more metals that are selected from molybdenum, tungsten, chromium, iron, cobalt, nickel, platinum, palladium, iridium, osmium, rhodium, rubidium and their mixture.
Roasting back end hydrogenation component exists with oxide form possibly in air, if necessary, can change into sulphided state to hydrogenation component improving under the condition of temperature to contact with the reducing atmosphere that contains hydrogen sulfide, mercaptan or other sulfocompound.This catalyzer can be by contacting vulcanization in situ with the sulfur-bearing raw material, or can vulcanize with immediately composition being exposed in the reducing atmosphere after roasting before any raw material contacts.
When needed, phosphorus component also can be added in the catalyzer.Or before forming particle by carrier substance and P contained compound blended method or be used in that the method for phosphoric acid adds phosphorus in the dipping solution.Usually phosphorus content is heavy at 1～30%(in the catalyzer), it is heavy to be preferably in 3-15%() (with P
2O
5Meter).
In addition, also can there be boron in the catalyst composition.Boron can element or the form of compound and be added in the composition with above-mentioned any method.That is, can form step at particle and add, or boron can for example join the compound existence of the boric acid form in the steeping fluid.Boron also can be added in the skeleton of selected zeolite.Under latter event, the y-type zeolite modification, and formed silica-alumina-borosilicate zeolite.
Catalyzer of the present invention is mainly used in the hydrocarbon feed hydrocracking, obtains more valuable than the harmonic(-)mean boiling point with than the product of low average molecular weight.This catalyzer is particularly useful for producing the middle runnings of boiling point about 300～700 (149～371 ℃) (recording with suitable ASTM methods of test).In addition, above-mentioned catalyzer also can be used for hydrogenation reaction such as hydrodenitrification and hydrogenating desulfurization.In fact general raw material comprises all heavy mineral oils and synthetic oil and cut thereof.For example, resembling raw materials such as straight run gas oil, vacuum gas oil, metal removal oil, atmospheric residue, diasphaltene vacuum residuum, coke oven distilled oil, catalytic cracking distillate, shale oil, tar sand oil, coal liquid all is available.Preferably raw material comprise contain 50%(body at least) boiling point is greater than the gas oil of 700 (371 ℃) components.Hydrocracking raw material can contain nitrogen, and contained nitrogen is usually with organic nitrogen compound form, heavy to 1.0%(with 1ppm) amount exist.Usually raw material can contain sulfocompound, and it is enough to make sulphur content to weigh greater than 0.15%().It also can contain the 80%(body) or more monocycle and/or polycyclic aromatic hydrocarbon compounds.
Used in the method for the invention hydrocracking condition is prior art those conditions commonly used in method for hydrogen cracking.The hydrocracking reaction temperature is 400～1200 °F (204～649 ℃), is preferably 600～950 °F (316～510 ℃).It is about 3 that reaction pressure is that normal pressure arrives, and 500Psig(24 132Kpag), is preferably 200～3000Psig(1379～20,685Kpag).Usually be equivalent to liquid hourly space velocity (LHSV) duration of contact and be about 0.1～15hr
-1, preferably be about 0.2～3hr
-1The hydrogen speed of circulation is 1000～50000 standard cube Foot (scf)/bucket charging (178～8888 standard m
3/ m
3), be preferably 2000～30000scf/ bucket charging (355～5333 standard m
3/ m
3).
Usually the conversion zone effluent is discharged from catalyst bed, carry out partial condensation and separate with vapour-liquid, its various components are reclaimed in fractionation then.Hydrogen (if necessary) and part or all of unconverted heavy material all are recycled in the reactor.
Therefore, the present invention can be referred to as a kind of method for hydrogen cracking of optionally producing intermediate oil, this method comprises and will contain the 50%(body at least), the boiling point hydrocarbon incoming flow that is higher than 371 ℃ component passes through catalyzer, contact with catalyst composition, this catalyzer is the composition of following component: (1) hydrogenation component; (2) contain the heat-resistant inorganic oxide matrix of aluminum oxide and (3) crystallization Hydrogen aluminosilicate zeolite, said zeolite has the X-ray powder diffraction spectrogram of y-type zeolite basically, and its ion-exchange capacity is greater than 0.07, and unit cell dimension is about 24.20～24.40
, NH
3-TPD acidity value is approximately less than 1.50, and said zeolite contacts 2～12 hours at 676～780 ℃ with steam, then at least under 426 ℃ of temperature at least drying and roasting carried out dehydroxylation in 1 hour; Keep this catalyzer simultaneously under hydrocracking condition; Reclaim the product logistics.
The following examples just further specify rather than limit the scope of the invention of the present invention.
Embodiment 1
In this embodiment, compared the effect that reduces by two kinds of different methods of zeolite acidity.In the A part, initial zeolite is heated in the presence of steam, the subsequent drying roasting, and initial zeolite heats in dry air in the B part.The acidity value of these zeolites is with above-mentioned NH
3-TPD tests and measures.The skeleton silicon oxide of these initial zeolites is 5: 1～8: 1 with the ratio of aluminum oxide.Preferably the skeleton silicon oxide is about 6: 1 with the ratio of aluminum oxide." main body (the bulk) " silicon oxide that this ratio non-equivalence proposes in some document and the ratio of aluminum oxide.These zeolites contain less than 0.1%(heavy) sodium.
The A part:
Use the y-type zeolite powdered sample of ammonium exchange, buy from Union Carbide Corporation before this sample, and buy from Praxair Technology, Inc now, and be referred to as LZ-Y82 in this article.With initial NH
3-TPD acidity value is 2.60, unit cell dimension is 24.56
Zeolite be loaded in the heating tube that is equipped with indirect heating equipment.According to desired acidity value, with this zeolite and the purified steam that obtains by softening water, in the 14.7Psia(1 bar absolute pressure) contact 2-12 hour under the temperature of pressure and 1250～1450 (676～788 ℃).When stop the heating period of selecting, stop logical vapour stream, in dry gas stream, in greater than 4 hours time, material temperature is dropped to envrionment temperature.In this step, this zeolite kept 1 hour at least under the temperature of 800 (426 ℃) at least.
Use aforesaid method, preparation five kinds of zeolite samples (A, B, C, D and F) under the listed temperature and time parameter of table I.The assay products sample shown in the table I, is listed characteristic X-ray powdery diffractometry spectrogram, unit cell dimension and the NH of zeolite Y
3-TPD acidity value.
The result shows that the acidity of zeolite can change (reduction) to preset value, and unit cell dimension reaches desired 24.20～24.40 simultaneously.Therefore, NH
3-TPD acidity can be regulated with the method for A part, and it uses the dry air roasting after being included in steam treatment.
The table I
Zeolite steam treatment condition unit cell dimension acidity
Sample time (hr) temperature (℃) (
) mole NH
3/ gram
A 2 1250（676） 24.36 1.50
B 2 1350（732） 24.35 1.13
C 2 1450（788） 24.29 0.65
D 12 1450（788） 24.25 0.14
E - - 24.36 1.30
F 6 1250（676） 24.35 1.25
The B part:
To have NH
3-TPD acidity value be 2.18 and unit cell dimension be 24.37
The y-type zeolite powdered sample (be referred to as LZ-20 usually, buy from Union Carbide Corporation in the past, buy by Praxair Technology, Inc now) of different ammonia exchange be loaded in the retort furnace (not having steam to exist in the method).Think that this starting material is the representative of the zeolite of the prior art optionally middle runnings cracking catalyst (for example United States Patent (USP) 4,419, the sort of catalyzer described in 271) that will be used for having used steam treatment.This zeolite is warmed up to 1300 °F (704 ℃), and under this temperature, kept 1 hour, make its cool to room temperature then.The analysis revealed of product is that X-ray powder diffraction spectrogram, the unit cell dimension of Y zeolite is 24.36
, NH
3-TPD acidity value is 1.30.This zeolite is the sample E that lists in the table I.
The result shows that dried roasting has reduced the NH of zeolite sample E
3-TPD acidity, and to not obviously influence of unit cell dimension.
It should be noted that in the processing of A part the unit cell dimension of initial zeolite and NH
3-TPD acidity value has all become.Yet, in the B part, have only the NH of initial zeolite
3-TPD acidity value reduces, and in fact unit cell dimension remains unchanged (24.37
To 24.36
).
At the relatively dry environment, for example do not add in the nitrogenous gas of steam at mobile, zeolite heat or roasting are proved the effective ways of the hydroxyl concentration that may reduce zeolite.Therefore, when such low acidity of needs and low hydroxyl concentration, this technology can merge in the general method for preparing catalyst.
Be not limited to theory, it is believed that acidity and unit cell dimension are irrelevant, and can be in the combination change acidity that has in the presence of steam and the dry air by various heating.Yet, and do not know to have steam heating and no steam heating respectively to the definite influence of zeolite acidity.
The preparation method obtains having the h-type zeolite of unaltered basically unit cell dimension (with respect to untreated zeolite) preferably.Dried roasting method of the present invention is preferably as the unique method that reduces zeolite acidity and hydroxyl concentration.If use other method, for example, dealuminization or ion-exchange are preferably in dry heat of the present invention and handle use before.Dehydroxylation is preferably in the zeolite that will handle to carry out before being added to the granules of catalyst of formation.
It is believed that in hydrothermal treatment consists, steam often stops " dehydroxylation " of zeolite.Obviously, when the unit cell dimension of needs change zeolite was processing intent, steam needed.The inventive method relates to the application of the zeolite that reduces hydroxyl concentration rather than the application of the zeolite that steam treatment is crossed.
The many zeolites that use in existing catalyzer are characterised in that their adsorptive poweies to water.This characteristic and determination test thereof, the existing introduction in for example former United States Patent (USP) of mentioning 4,401,556.These zeolites characterize adsorptive power of water vapor by their, its 25 ℃ and P/Po value be 0.10 o'clock less than the 5.00%(weight).The substances of test these embodiment of no use of these values is carried out.Yet, tested afterwards by the similar processing material that identical source obtains.Be equivalent to material that has born identical hydrothermal treatment consists such as zeolite C(below be used for catalyzer 3) 2.5%(that has an appointment is heavy) and the water adsorptive power.The initial substance of untreated A part (catalyzer of the numbering 7) 18%(that has an appointment is heavy) the water adsorptive power.Initial substance for the B part does not obtain this class value.As if the water adsorptive power reduce pro rata with the intensity of hydrothermal treatment consists.
The embodiment II
The purpose of present embodiment is to observe unit cell dimension and NH
3-TPD acidity is to the selectivity and the active influence of finished catalyst.
By with zeolite powder and aluminum oxide and silica-alumina refractory oxides substrate mixture, think that to obtain containing 5%(heavy) nonvolatile zeolite and 95%(be heavy) catalyzer of matrix of oxide and the amount selected is mixed, and the preparation catalyst composition.The mixture that obtains is pushed into about 1/16 inch * 1/2 inch (cylindrical bar of 0.16 * 1.27cm).With the extruded material drying, roasting 2 hours in the air of 650 (343 ℃) then.Then that the particle of roasting is heavy in order to be enough to making finished catalyst contain 1.0%() elemental nickel and 10.0%(be heavy) amount of the elemental tungsten ammonium tungstate and the nickelous nitrate (Ni(NO that exist
3)
26H
2O) aqueous solution volatilization is soaked altogether.Then with the catalyzer of dipping in 650 (343 ℃) down roasting 45 minutes, roasting 90 minutes when 1100 (593 ℃) again.With 6 kinds of catalyst compositions of method for preparing, each contains the y-type zeolite of preparation among a kind of embodiment 1.The table II has been enumerated respectively and has been contained the corresponding character of zeolite A to the catalyzer 1-6 of F.
With the method for introducing above, prepare catalyzer with the A of embodiment 1 part and the used initial zeolite material of B part.(unit cell dimension is 24.56 with A initial zeolite partly
, NH
3-TPD is 2.60) preparation No.7 catalyzer, (unit cell dimension is 24.37 with B initial zeolite partly
, NH
3-TPD is 2.18) preparation No.8 catalyzer.The related properties of No.7 catalyzer and No.8 catalyzer also provide in the table II.
The table II
Catalyzer numbering zeolite unit cell dimension NH
3-TPD value
1 A 24.36 1.50
2 B 24.35 1.13
3 C 24.29 0.65
4 D 24.25 0.14
5 E 24.36 1.30
6 F 24.35 1.25
7 A part initial substances 24.56 2.60
8 B part initial substances 24.37 2.18
Above-mentioned each catalyzer is all tested its activity and selectivity in the following method.The vacuum gas oil of the preheating with the chemistry shown in the table III and physical properties is contained the isothermal reactor of having an appointment with 29CC60～80 order quartz sand blended 75CC granules of catalyst in one way by one.Operating parameters is 2000Psig(13,790KPag), 1.0LHSV, hydrogen internal circulating load 10, and 000scf/bbl(1,778 standard rices
3/ rice
3) (hydrogen purity 90～95%), be about 4 days runtime.The conditioned reaction actuator temperature makes the 85%(of raw material heavy) change into the product that boiling point is lower than 700 (371 ℃).Percentage conversion is that the liquid chromatography boiling range analytical calculation by product obtains.
The table III
Vacuum gas oil character
15.6 ℃ 0.9248 of proportion distillation ℃
15.6 ℃ of 21.5 initial boiling point 280 of proportion ° API
Pour point ℃ 26.7 5/10% 340/372
Aniline point ℃ 75.0 20,/30 398/419
Sulphur (LECO) %(is heavy) 2.24 40,/50 439/455
Nitrogen (Kjeldahl-Gunning method (for nitrogen determination)) 60,/70 473/490
ppm 1100 80/90 514/544
Carbon %(is heavy) 85.82 final boiling point 582
Hydrogen %(is heavy) 11.64 yield % 99.0
Bromine valency 5.0
98.9 ℃ of centistokes 6.954 of viscosity
Conradson carbon residue %(is heavy) 0.42
Top test-results is listed in the table IV.Catalyzer 1-4 and 6 is that the A part material by the embodiment I obtains.The data of these five catalyzer show at unit cell dimension hour: (1) activity of such catalysts descends; (2) selectivity increases.
The table IV
Catalyst activity, °F (℃) (at transformation efficiency is NH to selectivity
3-TPD
300 values during numbering (85% 85%(that transforms is weighed)
Temperature of reactor)～700 product %
(weight))
1 774（412） 59 1.50
2 778（414） 59 1.13
3 786（419） 61 0.65
4 797（425） 63 0.14
5 782（417） 60 1.30
6 782（417） 59 1.25
7 761（405） 55 2.60
8 782（417） 56 2.18
These data show that also total comprehensive activity of catalyzer 1-6 of the present invention and the catalyzer 7 and 8 that selectivity ratios contains untreated high acidity catalyzer are far better.Comparison shows that of catalyzer 1-6 and catalyzer 7 and 8 is as the NH of zeolite component
3-TPD acidity value is approximately less than obtaining the result of catalyzer preferably at 2.00 o'clock.More precisely, though catalyzer 7 shows higher activity (761/405 ℃), its selectivity is unacceptable (55%(is heavy)).Yet, it is also noted that the unit cell dimension of contained zeolite is 24.56 in catalyzer 7
, it is in the preferable range 24.20～24.45 of aforesaid United States Patent (USP) 4,401,556
Outside.
But the unit cell dimension of catalyzer 8 its zeolites is 24.37 within this scope
, show similar activity (782/417 ℃), but its selectivity very poor (56%(is heavy)).As seen from the above-described embodiment, the NH of zeolite component
3-TPD acidity value influences the overall performance of hydrocracking catalyst.
As previously mentioned, the zeolite initial substance of B part obviously is within many preferable range of the zeolite introduced in the people's such as prior art references Bezman that quote in front the United States Patent (USP) 4,401,556.This is that commercially available unit cell dimension is 24.37
, and passed through the material of hydrothermal treatment consists.An exception of the zeolite of the present invention in the preferable range of the reference of quoting is that its ion-exchange capacity (determining by people's such as Bezman reference) is 0.171.This material is used in the catalyzer 8.The reference of Bezman points out that ion-exchange capacity should be greater than 0.07.
The material that dried roasting of the present invention will be used for catalyzer 8 changes into the material that is used to prepare catalyzer 5.Catalyzer 5 has better choice under identical activity, and it is a kind of fine catalyzer.Yet the difference of the unit cell dimension of catalyzer 5 and 8 zeolite almost is negligible.Therefore, improve selectivity of catalyst than expecting big many of the selectivity of raising with the inventive method by changing unit cell dimension.The ion-exchange capacity that is used for the zeolite E of high-quality catalyzer 5 is 0.091.This is worth above 28% of people's such as Bezman the described upper limit of reference.
Claims (8)
1, is in 149～371 ℃ the method for hydrogen cracking of middle runnings producing boiling point, under hydrocracking condition, hydrocarbon feed stream fed wherein that (unit cell dimension of this zeolite is 24.20～24.40 with containing heat-resistant inorganic oxide matrix and hydrogen y-type zeolite
) catalyst composition contact; And reclaim product and flow; Improvement part comprises having ion-exchange capacity, bonded hydroxy content greater than 0.07 low as to be enough to make NH
3-TPD acidity value is used as said zeolite less than 2.00 low acidity zeolite.
2, a kind of method for hydrogen cracking of selecting production middle runnings, comprising and will contain the 50%(body at least) boiling point contacts with catalyst composition in the hydrocarbon incoming flow of component more than 371 ℃, keep catalyzer under hydrocracking condition, and reclaim product and flow, said catalyst composition comprises following component: (1) hydrogenation component, (2) contain the heat-resistant inorganic oxide matrix of aluminum oxide, (3) crystallization hydrogen Y type aluminosilicate zeolite, the unit cell dimension of this zeolite is 24.20～24.40
, ion-exchange capacity greater than 0.07, NH
3-TPD acidity value is less than 1.50.
3, according to the method for claim 2, it is heavy that wherein said composition contains 2-20%() said zeolite.
4, according to the method for claim 2, wherein said heat-resistant inorganic oxide matrix comprises the mixture of aluminum oxide and silica-alumina.
5, according to the method for claim 4, it is heavy that wherein said matrix contains 45～90%() silica-alumina, it is heavy also to contain 5～45%() aluminum oxide.
6, according to the method for claim 2, wherein said hydrogenation component is selected from VI B family metal, VIII family metal and their compound.
7, according to the method for claim 2, wherein said VI B family component is selected from molybdenum, tungsten and their compound, and said VIII family metal component is selected from nickel, cobalt and their compound.
8, a kind of middle runnings selective hydrocracking catalyst composition, it comprises following component: (1) hydrogenation component, (2) the basic X-ray powder diffraction spectrogram, ion-exchange capacity that salic heat-resistant inorganic oxide matrix, (3) have a y-type zeolite greater than 0.07, unit cell dimension is 24.20～24.40
And NH
3-TPD acidity value is less than 1.50 crystallization Hydrogen aluminosilicate zeolite.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US316,723 | 1989-02-28 | ||
| US07/316,723 US4894142A (en) | 1987-03-24 | 1989-02-28 | Hydrocracking process employing low acidity Y zeolite |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1053256A true CN1053256A (en) | 1991-07-24 |
| CN1024561C CN1024561C (en) | 1994-05-18 |
Family
ID=23230363
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 90100772 Expired - Lifetime CN1024561C (en) | 1989-02-28 | 1990-01-13 | Middle distillate hydrocracking catalyst employing low acidity Y zeolite |
Country Status (2)
| Country | Link |
|---|---|
| CN (1) | CN1024561C (en) |
| AU (1) | AU624892B2 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1064862C (en) * | 1994-11-09 | 2001-04-25 | 中国石油化工总公司 | Hydrogen cracking catalyst |
| CN100587040C (en) * | 2002-11-08 | 2010-02-03 | 切夫里昂美国公司 | Extremely low acidity USY and homogeneous, amorphous silica-alumina hydrocracking catalyst and process |
| CN100587039C (en) * | 2002-11-08 | 2010-02-03 | 切夫里昂美国公司 | Extremely low acidity ultrastable Y zeolite catalyst composition and process |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5601798A (en) * | 1993-09-07 | 1997-02-11 | Pq Corporation | Process for preparing zeolite Y with increased mesopore volume |
| CN1059846C (en) * | 1994-11-09 | 2000-12-27 | 中国石油化工总公司抚顺石油化工研究院 | Light oil type hydrogen cracking catalyst and preparation method thereof |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4604187A (en) * | 1981-12-04 | 1986-08-05 | Union Oil Company Of California | Hydrocracking with rare earth-containing Y zeolite compositions |
| US4661239A (en) * | 1985-07-02 | 1987-04-28 | Uop Inc. | Middle distillate producing hydrocracking process |
| US4894142A (en) * | 1987-03-24 | 1990-01-16 | Uop | Hydrocracking process employing low acidity Y zeolite |
-
1990
- 1990-01-05 AU AU47720/90A patent/AU624892B2/en not_active Expired
- 1990-01-13 CN CN 90100772 patent/CN1024561C/en not_active Expired - Lifetime
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1064862C (en) * | 1994-11-09 | 2001-04-25 | 中国石油化工总公司 | Hydrogen cracking catalyst |
| CN100587040C (en) * | 2002-11-08 | 2010-02-03 | 切夫里昂美国公司 | Extremely low acidity USY and homogeneous, amorphous silica-alumina hydrocracking catalyst and process |
| CN100587039C (en) * | 2002-11-08 | 2010-02-03 | 切夫里昂美国公司 | Extremely low acidity ultrastable Y zeolite catalyst composition and process |
Also Published As
| Publication number | Publication date |
|---|---|
| AU4772090A (en) | 1991-08-01 |
| AU624892B2 (en) | 1992-06-25 |
| CN1024561C (en) | 1994-05-18 |
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