CN1075551C - Hydrocracking process for producing intermediate distillate - Google Patents

Abstract

A hydrocracking process for producing middle distillate oil, using a high and middle distillate oil type nitrogen-resistant hydrocracking catalyst, the composition of which is Y zeolite 5-40w%, amorphous silicon aluminum 10-50w%, alumina 15-30w% %, Group VIB metal oxides 10-40w%, VIII metal oxides 1-10w%. The hydrocracking process allows high nitrogen feed to the cracking section with high mid-oil selectivity for the production of middle distillates.

Description

A kind of hydrocracking process of producing intermediate oil

The present invention relates to a kind of handiness and produce the hydrocracking process of intermediate oil.

Hydrocracking is a kind of important refining of petroleum means, after the hydrogen source of cheapness is resolved, hydrocracking technology is developed rapidly, the use of zeolite in hydrocracking catalyst is a qualitative leap of hydrocracking technology, it has changed, and amorphous type hydrocracking catalyst activity was low in the past, the shortcoming that running period is short, not only make the stability and the life-span of catalyzer better, and reduced the severity of reaction process, thereby the flexibility of operation of catalyzer is strengthened, and therefore present most hydrocracking full scale plant all uses the catalyzer that contains zeolite.

For middle oil type hydrocracking catalyst, except considering activity, also need consider middle distillates oil selectivity, zeolite facies no doubt can increase the lytic activity of catalyzer to the stronger acid sites of acid sial, but its intensive cracking ability can cause declining to a great extent of middle distillates oil selectivity, how in raising or assurance catalyst activity, but not sacrifice middle distillates oil selectivity in a large number, search out a kind of better balance in active and this a pair of contradiction of middle distillates oil selectivity, be an emphasis of middle oil type hydrocracking catalyst development and exploitation always.

Many hydrocracking technologies of exploitation integrate and say that its technology generally can be divided into one-stage process and two-stage method at present, and operating method mainly can be divided into recycle to extinction and once pass through.Non-noble metal hydrocracking catalyst is except adopting the two-stage method, generally be widely used in the one-stage process technology, but because the zeolite that contains in the catalyzer is to impurity sensitivities such as the sulphur in the charging, nitrogen, easily poison in the acidic cleavage center, so containing the hydrocracking catalyst of zeolite is generally used in the one-stage serial technology, for making the cracking catalyst steady running, generally need under refining section catalyst for refining cooperates, cracking zone feed nitrogen content to be reduced to below the 10ug/g.Compare with two-stage process, do not establish gas in the middle of refining exactly section of so-called one-stage serial and the cracking zone and mention fractionating system, thereby can reduce plant investment and operating cost.The hydrofining section is also referred to as gives processing section, and this section uses does not have a lytic activity and based on the Hydrobon catalyst of hydrogenation activity, be used for material enter remove most sulphur, nitrogen before the cracking zone and carry out hydrogenation saturated.

Along with all over the world the exploitation the oil quality worse and worse, density is more and more heavier, and existing hydroeracking unit is to increasing the requirement of treatment capacity, the hydrocracking process process is faced with new problem, especially harsher requirement has been proposed the hydrocracking catalyst performance of using, therefore need consider to some extent the anti-nitrogen that contains the zeolite hydrocracking catalyst, on the basis that guarantees catalyst activity and middle distillates oil selectivity, make it have high anti-nitrogen, adapting to the variation requirement of catalyzer, thereby has greater flexibility aborning to stock oil and operating procedure.

Shell company had once released a kind of hydrocracking process that allows high nitrogen charging to market, characteristics are that this process is used a kind of commercial anti-nitrogen type hydrocracking catalyst Z-763, this hydrocracking catalyst allows feed nitrogen content 30～50ug/g, but use-pattern is the upper bed layer that is seated in the cracking zone reactor, though this has improved whole hydrocracking process to the adaptability of poor heavy raw material and deal with the ability of harsh reaction conditions, but the catalyzer of filling different performance in the same reactor, the bed temperature difference can appear, for the balancing run of whole technology brings difficulty.Certainly, also have in the prior art by significantly improving the active mode of cracking catalyst and offset catalyzer and deal with the needed temperature compensation of high nitrogen charging, a kind of hydrocracking catalyst with handiness production petroleum naphtha and boat coal of uniting oily company as the U.S. once ran into 100ug/g average feed nitrogen content up and down at full scale plant, though still can steady running, but temperature compensation is very big, about 20～40 ℃, and the naphtha yield height, middle distillates oil selectivity is low.

EP0028938A1 discloses a kind of middle runnings oil type hydrocracking catalyst that contains zeolite, and characteristics have been to use a kind of y-type zeolite UHP-Y, and its preparation process comprises SiO ₂/ Al ₂O ₃Mol ratio is 4.5～9, and lattice constant is 24.20～24.45 * 10 ^-10M, specific surface 350m ²The raw material zeolite of/g, in 0.2～10 normal atmosphere, 725～870 ℃ of following hydrothermal treatment consists, because this zeolite water thermal treatment temp height, thereby the heatproof requirement to High Temperature Furnaces Heating Apparatus is very high in the preparation process, and energy consumption is also high.From the related hydrocracking process of embodiment, the Arabic VGO of hydrocracked, treated, though middle distillates oil selectivity 86v%, transformation efficiency has only 60v%, temperature of reaction is but up to 407 ℃; Handling easily cracked Kuwait VGO, reach the 70v% transformation efficiency, although temperature of reaction decreases, is 397 ℃, and middle distillates oil selectivity is 74v% only, illustrates that catalyst activity and middle distillates oil selectivity can not be well balanced, and relatively poor to the adaptability of different material.

The US4664776 patent disclosure hydrocracking process of oil in a kind of produce, the hydrocracking catalyst that this hydrocracking process relates to has used zeolite component, comprises a kind of modified Y zeolite, its SiO ₂/ Al ₂O ₃Mol ratio is 3.5～6, and lattice constant is 24.25～24.35 * 10 ^-10M, specific surface 500～700m ²/ g, Na ₂O content＜0.5w% is at 25 ℃, P/P ₀Be 0.1 o'clock, water adsorption amount is less than 8w%; And be used a kind of Al ₂O ₃-SiO ₂Dispersion system, general more than 80% though its middle distillates oil selectivity is higher, reach 60v% and transform, by using a kind of 75% high silicon sial that is dispersed with at Al ₂O ₃-SiO ₂Dispersion system, and cooperate the catalyzer contain zeolite, temperature of reaction is minimum also only to drop to 389 ℃, the temperature of reaction of example catalyst is generally at 389～413 ℃, the hydrocracking process of this patent is not mentioned high nitrogen charging yet, and points out preferably hydrodenitrification and/or the hydrogenating desulfurization charging of charging that suit.

Because the characteristics of crude oil in China mainly are the high nitrogen of low-sulfur, domestic refinery relatively abroad more pays close attention to the anti-nitrogen of hydrocracking catalyst, therefore during oil type hydrocracking catalyst is developed in domestic, except the middle distillates oil selectivity that will improve catalyzer, anti-nitrogen more needs to consider, particularly more and more heavier, the quality of the crude oil along with exploitation all over the world worse and worse, enter the nineties after, the anti-nitrogen that contains the zeolite hydrocracking catalyst is also more and more caused investigator's interest.The zeolite component of catalyzer is related very big with the anti-nitrogen ability of catalyzer to the middle oily yield that contains the zeolite hydrocracking catalyst, but the cooperation of support of the catalyst component or synergy also are the comparison keys.Sial is absolutely necessary for the amorphous type hydrocracking catalyst, because sial is the source at acidic cleavage center, though to containing the catalyzer of zeolite, provide main lytic activity by zeolite, not necessarily must use sial, but because the acid sites of acid sial is useful to oily yield in improving, therefore most of catalyzer all uses sial and seeks best of breed with zeolite component.

The object of the present invention is to provide a kind of in oily yield height, active good hydrocracking process, treatment of heavy hydrocarbon material is to produce intermediate oil.The hydrocracking catalyst that hydrocracking process of the present invention is related can allow the high nitrogen charging of cracking zone, to improve the handiness of hydrocracking process process.

The characteristics of hydrocracking process of the present invention are that a kind of activity is good, middle distillates oil selectivity is high by using, the strong catalyzer of anti-nitrogen ability obtains, and the characteristics of this catalyzer depend on its super-hydrophobic Y zeolite that matches in forming and the feature of sial thereof.Said catalyzer has used a kind of super-hydrophobic Y zeolite as the main acidic components of catalyzer, and a kind of amorphous aluminum silicide is as the auxiliary acid component and the carrier component of catalyzer.Catalyzer also contains and is selected from VI B family and VIII family metal is made hydrogenation component.Catalyst specific surface 150～350m that hydrocracking process of the present invention relates to ²/ g, pore volume 0.25～0.45ml/g, infrared acidity 0.25～0.55mmol/g.Best catalyst specific surface 200～300m ²/ g, pore volume 0.30～0.40ml/g, infrared acidity is 0.35～0.45mmol/g.

The catalyzer that hydrocracking process of the present invention relates to use consists of a kind of super-hydrophobic Y zeolite 5～40w%, a kind of amorphous aluminum silicide 10～50w%, alumina adhesive 15～30w%, VI B family metal is selected from Mo and/or W, by containing 10～40w% in the metal oxide compound catalyzer, VIII family metal is selected from Co and/or Ni, by containing 1～10w% in the metal oxide compound catalyzer.Further, the catalyzer that hydrocracking process of the present invention relates to use preferably contains zeolite 10～35w% involved in the present invention, amorphous aluminum silicide 20～40w%, alumina adhesive 15～30w%, the VI B family metal of carrying is selected from Mo and/or W, by containing 15～30w% in the metal oxide compound catalyzer, VIII family metal is selected from Co and/or Ni, by containing 4～8w% in the metal oxide compound catalyzer.

Super-hydrophobic Y zeolite during catalyzer involved in the present invention is formed has following feature: SiO ₂/ Al ₂O ₃Mol ratio is 5.0～25, and lattice constant is 24.25～24.40 * 10 ^～10M,＞20 * 10 ^-10The secondary pore volume of m accounts for more than 40% of total pore volume, specific surface 600～850m ²/ g, infrared acidity 0.20～0.60mmol/g, Na ₂O content＜0.2w%, non-framework aluminum account for 10～50w% of the total aluminium of zeolite, at 25 ℃, and P/P ₀Be 0.1 o'clock, water adsorption amount is less than 5w%, and propyl carbinol adsorption experiment residual value is less than 0.4, loading capacity＜0.07; The further feature of super-hydrophobic Y zeolite involved in the present invention is: SiO ₂/ Al ₂O ₃Mol ratio is 6.0～17, lattice constant 24.25～24.35 * 10 ^-10M,＞20 * 10 ^-10M secondary micropore accounts for more than 50%, specific surface 700～800m ²/ g, infrared acidity 0.25～0.50mmol/g.

Though prior art some modified Y zeolite solid acid amounts be reduced to a certain extent, be not enough to significantly improve middle distillates oil selectivity, and strong acid center is too much, also responsive to nitrogen.Super-hydrophobic Y zeolite during the catalyzer that hydrocracking process of the present invention relates to is formed is that the raw material Y zeolite is carried out pressurized thermal water processing and chemical after-treatment reason again after amine and acid treatment dealuminzation step are taken off in roasting, the sial molecular ratio of its modified Y zeolite improves, and the solid acid amount reduces.Super-hydrophobic Y zeolite during catalyzer involved in the present invention is formed is after deep sealumination modified, and infrared acidity is reduced to 0.2～0.6mmol/g, best 0.25～0.5mmol/g, and zeolite acidity is low, and its cracking is relaxed, and has guaranteed middle distillates oil selectivity; Though zeolite acidity involved in the present invention reduces by a relatively large margin, its strength of acid characteristics make zeolite involved in the present invention have the acid sites of all kinds of intensity of suitable proportion distribution, have just protected the cracking activity to heavy hydrocarbon material.As seen from Table 1, super-hydrophobic Y zeolite during catalyzer involved in the present invention is formed has the acid sites of the different strength of acid of two classes, hydrocracking catalyst is to the active needs of cracking when making this catalyzer can not only satisfy the production intermediate oil, simultaneously less acid site and more weak acid sites have reduced the chance of second pyrolysis and excessive fragmentation generation, guaranteed not only have higher lytic activity in the catalyzer use, also had good middle distillates oil selectivity simultaneously.

Table 1 zeolite NH involved in the present invention ₃-TPD result

The maximum peak temperature (℃) acid site number * 10 ²⁰(individual/g)

N is complete for TM I TM II n I n II

208 385 1.85 1.96 3.95

Zeolite during catalyzer involved in the present invention is formed is the acid site of a kind of ratio, lattice constant and secondary pore with higher crystallinity, specific surface, suitable non-framework aluminum and total aluminium and more medium tenacity and the super-hydrophobic zeolite at weak acid center.We find, at lesser temps (550 ℃～700 ℃), roasting Na under 0.01～1.0MPa water vapour pressure ₂The Y zeolite of O content＜0.2w% can be prepared SiO ₂/ Al ₂O ₃Mol ratio is 5.2～6.0 super-hydrophobic Y zeolite, uses chemical process selectivity dealuminzation again, makes SiO ₂/ Al ₂O ₃Mol ratio is 5.0～25 super-hydrophobic Y zeolite.Compare with the Y zeolite of prior art for preparing, zeolite involved in the present invention has higher degree of crystallinity, specific surface, and zeolite surface has two or more acid hydroxy groups, more middle strong acid and weak acid center simultaneously.

Super-hydrophobic Y zeolite during catalyzer involved in the present invention is formed is the super-hydrophobic Y zeolite of handling through modification, and it has very high absorption property to non-polar hydrocarbon, and poor to the polar water molecules adsorptivity, is commonly referred to the hydrophobic type Y zeolite, and it is at 25 ℃, P/P ₀Be 0.1 o'clock, water regain＜5w%.After zeolite involved in the present invention was handled through modification, its lattice constant was fixed in the extremely narrow scope, and general 24.20～24.45 * 10 ^-10M, best 24.25～24.35 * 10 ^-10M.This zeolite also has tangible secondary pore, and promptly the zeolite mesopore increases after modification is handled, and is accompanied by the increase of specific surface, pore volume, specific surface 600～850m ²/ g, best 700～800m ²/ g; Pore volume 0.2～0.6ml/g, best 0.3～0.5ml/g;＞20 * 10 ^-10The secondary pore pore volume of m accounts for more than 50% of total pore volume.

The high-ratio surface of zeolite involved in the present invention and more secondary pore have reduced the chance that second pyrolysis takes place, accelerated reaction mechanism, help the raising of hydrogenation metal dispersion and hydrogenation activity, this also helps polycyclic aromatic hydrocarbons or the active raising of nitrogenous heterocyclic open loop simultaneously, and help the turnover of reactant and resultant, reduce the possibility of carbon deposit and catalyst deactivation, make it be used for catalyzer involved in the present invention, can bear and the contacting of high nitrogen charging.Therefore, be that the hydrocracking catalyst of acidic components is compared with Y zeolite with prior art for preparing, be that the hydrocracking catalyst of acidic components has high reactivity and high middle distillates oil selectivity with zeolite involved in the present invention.

Amorphous silicon al composition silica content 10～60w% during the catalyzer that hydrocracking process of the present invention relates to is formed, best 20～40w%, other physico-chemical property is characterized as: specific surface 350～600m ²/ g, general 400～550m ²/ g, best 450～500m ²/ g; Pore volume 0.8～1.5ml/g, general 0.9～1.4ml/g, best 1.0～1.3ml/g; Infrared acidity 0.25～0.55mmol/g, general 0.30～0.50mmol/g, best 0.40～0.45mmol/g is a kind of active carrier component, cooperates zeolite component to provide lytic activity for catalyzer, supports the hydrogenation metal component simultaneously.

The amorphous aluminum silicide of prior art is as the acidity of catalyst component, need be dispersed in than high-ratio surface with than the refractory oxide such as the γ-Al of large pore volume ₂O ₃Go up with common carrier as catalyzer, this is because the specific surface and the pore volume of prior art sial are all less, is not enough to carry a large amount metal component.The amorphous silicon al composition preparation process that hydrocracking process of the present invention relates to the catalyzer of use does not resemble some prior art, the too much meeting that the silicon amount is introduced has influence on the size of the finished product specific surface and pore volume strongly, amorphous aluminum silicide involved in the present invention still can obtain high-ratio surface large pore volume amorphous aluminum silicide in a very wide high silicon content scope.Hydrocracking process of the present invention relates to the sial amorphization degree height in the catalyst component, so porous index height such as pore volume, specific surface, also avoided forming more strong acid center under crystallization tendency, these characteristics also all help the raising of the anti-nitrogen performance of catalyzer and the raising of cracking and hydrogenation activity.This sial is used for catalyzer in addition, can guarantee that the pore volume in catalyzer 4～15nm aperture reaches 70% of the total pore volume of catalyzer at least, is more suitable for the treating processes of heavy VGO.

Hydrocracking process of the present invention relates to the moulding of the catalyzer of use can adopt various known routine techniquess, and as balling-up or extrusion, supporting of metal can be adopted coprecipitation method, kneading method, pickling process etc.The first extruded moulding of general employing, the mode of impregnating metal component again, because this method is in the easier realization of industrial production, be about to Y zeolite involved in the present invention by 5～40w% (by catalyzer) and amorphous aluminum silicide 10～50w% (by catalyzer) dry powder blend evenly after, the tackiness agent that adding 15～30w% (by catalyzer) aperture aluminum oxide makes through the nitric acid peptization mixes pinches or is rolled into paste, extruded moulding, be generally garden post bar, diameter 1.2～1.8mm also can adopt special-shaped bar such as trifolium or Herba Galii Bungei type.Behind carrier strip drying, the calcination activation, adopt hole saturation method or excess solution method dipping hydrogenation metal, the hydrogenation metal dipping solution comprises VI B family and VIII family metal, gets finished catalyst after the carrier strip drying behind the carrying metal, the activation.

Because the catalyzer that hydrocracking process of the present invention relates to has used a kind of modification super-hydrophobic Y zeolite, this zeolite has the matrix than demulcent lytic activity and anti-nitrogen, and used a kind of amorphous acid sial of large pore volume high-ratio surface, cooperate the use of zeolite involved in the present invention, the carrying of auxiliary acid and hydrogenation metal and the main space and the specific surface that are used to react are provided, therefore the pore distribution concentration of the catalyzer that relates to of the hydrocracking process of the present invention that obtains, the pore volume in 4～15nm aperture reaches 70% of the total pore volume of catalyzer at least, generally between 70～90%, the best 200～300m of specific surface ²/ g, pore volume 0.30～0.40ml/g, these character all help the performance of catalyst hydrogenation activity, have not only strengthened the anti-nitrogen ability of catalyzer, also make catalyzer that hydrocracking process of the present invention relates to use when activity improves, keep higher middle distillates oil selectivity.Hydrocracking process of the present invention relates to the infrared acidity 0.25～0.55mmol/g of catalyzer of use, have the characteristics of amorphous type and zeolite containing catalyst concurrently, when at utmost keeping amorphous type catalyzer middle distillates oil selectivity height and adapting to the advantage of high nitrogen feed conditions, also has higher activity.The hydrocracking process of the present invention not only adaptability to poor heavy raw material is wider, and has the handiness in the technological operation, this brings more flexibly for oil refining manufacturer in intermediate oil production and select, and as handling worse material, also can deal with the charging under the high nitrogen condition.

The prior art use contains the zeolite hydrocracking catalyst and is used for the one-stage serial hydrocracking process, and this process has two reactors, first section filling Hydrobon catalyst, and second section filling contains the crystal formation hydrocracking catalyst of zeolite.First section interior catalyzer of hydrofining reactor generally is the catalyzer with the inert carrier-supported hydrogenation metal that does not contain zeolite, mainly provide hydrogenation activity with impurity and saturated such as desulfurization, nitrogen, oxide compounds to the hydrogenation of unsaturated hydrocarbons in the stock oil, to improve cracked charge character, reduce the cracking zone load, guarantee that cracking zone contains the active and stable of zeolite hydrocracking catalyst long-term operation.Because zeolite is to the impurity sensitivities such as sulphur oxynitrides in the stock oil, poisoning and deactivation need give refining before stock oil contacts them easily, to remove most of poisonous substance, the cracking zone hydrocracking catalyst is active and stable in the maintenance hydrocracking process.The zeolite hydrocracking catalyst general requirement cracking zone feed nitrogen content that contains of prior art is not more than 10ug/g, otherwise cracking catalyst can rapid inactivation.Hydrocracking process of the present invention makes one-stage serial hydrocracking process of the present invention allow cracking zone nitrogen content 10～50ug/g, even can reach nitrogen content 50～100ug/g owing to relate to the catalyzer of use.Because cracking zone allows high nitrogen charging, therefore can reduce the severity of hydrofining section operation, be unlikely to influence the running period of whole hydrocracking process on the one hand because of tying down of catalyst for refining, can improve the treatment capacity of whole process on the other hand, have higher handiness on the technology, can increase productivity effect.

The characteristics of hydrocracking process of the present invention are that also stock oil adaptability is strong, be particularly suitable for treatment of heavy hydrocarbon material, as gas oil, vacuum distillate, take off pitch prill oil, catalytic cracking turning oil, shale oil, coal tar wet goods, the boiling range scope of heavy hydrocarbon material is at 250～600 ℃, generally at 300～550 ℃.And under the highly active prerequisite of performance, also shown high middle distillates oil selectivity.

The hydrocracking condition of hydrocracking process of the present invention is under the hydrogen existence condition, stock oil is contacted system response pressure 5～20MPa, hydrogen-oil ratio 100～5000, air speed 0.1～5.0hr with catalyzer ^-1, 340～420 ℃ of cracking zone temperature of reaction.Further, hydrocracking process of the present invention is at pressure 7～18MPa, hydrogen-oil ratio 500～2500, air speed 0.5～2.0hr ^-1, 350～410 ℃ of cracking zone temperature of reaction, preferably at pressure 12～15MPa, hydrogen-oil ratio 1000～1500, air speed 0.8～1.5hr ^-1, 360～400 ℃ of temperature of reaction.

The catalyzer that hydrocracking process of the present invention relates to use is used for the production of hydrocracking process intermediate oil, has the characteristics of the high middle distillates oil selectivity of high reactivity.During stock oil that catalyst treatment various types of properties of the present invention differs greatly, keep being not less than the transformation efficiency of 65v%, middle distillates oil selectivity generally is not less than 80%, and temperature of reaction generally is not higher than 385 ℃ (under conventional low nitrogen feed conditions), high nitrogen charging guarantees that temperature of reaction generally is not higher than 400 ℃, the contradiction of balanced well active and middle distillates oil selectivity.Compare with the existing similar catalyst of industrial use, the catalyzer that hydrocracking process of the present invention relates to use all shows better activity or middle distillates oil selectivity.The catalyzer that hydrocracking process of the present invention relates to use also has operational handiness, can take recycle to extinction or once-through operation mode according to product demand, and by adjusting operational condition, coal or diesel oil but the production of maximum ground is navigated.Hydrocracking process of the present invention relates to the good hydrogenation performance and the open-loop performance of catalyzer of use, make it be particularly suitable for processing high aromatic hydrocarbons height and do inferior heavy pledge material, and the hydrocracking product property excellence that is obtained, can produce high smoke point boat coal, high hexadecane value and low aromatics diesel or diesel oil blending component, hold concurrently and produce fine reformer feed and/or preparing ethylene by steam cracking raw material.

Following case description hydrocracking process of the present invention relates to the Preparation of catalysts and the catalytic performance characteristics of use.

Example 1:

Get this. related Y zeolite 19.5g (SiO in the invention scope ₂/ Al ₂O ₃Mol ratio 15, infrared acidity 0.35mmol/g), macropore amorphous aluminum silicide 109.8g (SiO ₂Content 45w%, specific surface 365m ²/ g, pore volume 0.956ml/g, infrared acidity 0.40mol/g), mix with tackiness agent behind the mixing and pinch into paste (tackiness agent wherein is to make by the rare nitric acid peptization 68.5g aperture pseudo-boehmite that is dissolved in 135ml distilled water with 8.2ml 40% nitric acid), behind the post orifice plate extruded moulding of φ 1.7mm garden, 110 ℃ of dryings 10 hours, again through 500 ℃ of activation 3 hours carrier of the present invention.Use ammonium metawolframate 49.8g, the steeping fluid dipping of nickelous nitrate 43.4g preparation got the catalyst A that hydrocracking process of the present invention relates to use in 3 hours through 10 hours, 500 ℃ activation of 110 ℃ of dryings again.Catalyzer consists of WO ₃23.0w%, NiO 7.1w%, hydrophobic Y zeolite 10w%.Catalyst specific surface 228m ²/ g, pore volume 0.388ml/g.

Example 2:

Get related Y zeolite 38.5g (SiO in the scope of the invention ₂/ Al ₂O ₃Mol ratio 12, infrared acidity 0.31mmol/g), macropore amorphous aluminum silicide 88.6g (SiO ₂Content 25w%, specific surface 332m ²/ g, pore volume 0.922ml/g, infrared acidity 0.34mmol/g), mix with tackiness agent behind the mixing and pinch into paste (wherein tackiness agent is to make with rare nitric acid peptization 54.8g aperture pseudo-boehmite that 5.7ml 40% nitric acid is dissolved in 105ml distilled water), behind the post orifice plate extruded moulding of φ 1.7mm garden, 110 ℃ of dryings 10 hours, again through 500 ℃ of activation 3 hours carrier; Use ammonium metawolframate 54g, the steeping fluid dipping of nickelous nitrate 42.1g preparation got the catalyst B that hydrocracking process of the present invention relates to use in 3 hours through 10 hours, 500 ℃ activation of 110 ℃ of dryings again.Catalyzer consists of WO ₃23.2w%, NiO 7.2w%, hydrophobic Y zeolite 20w%.Catalyst specific surface 249m ²/ g, pore volume 0.332ml/g.

Example 3:

Get related Y zeolite 53.3g in the invention scope, macropore amorphous aluminum silicide 60.0g (SiO ₂Content 35w%, specific surface 396m ²/ g, pore volume 0.996ml/g, infrared acidity 0.34mmol/g), the mixed paste (wherein tackiness agent is to make with rare nitric acid peptization 41.1g aperture pseudo-boehmite that 4.7ml 40% nitric acid is dissolved in 85ml distilled water) of pinching into of back and tackiness agent is mixed, behind the post orifice plate extruded moulding of φ 1.7mm garden, got carrier in 10 hours 110 ℃ of dryings; Use by molybdenum oxide 39g, nickelous nitrate 41g, the steeping fluid dipping of phosphoric acid 2.5ml preparation got the catalyzer C that hydrocracking process of the present invention relates to use in 3 hours through 10 hours, 500 ℃ activation of 110 ℃ of dryings again.Catalyzer consists of MoO ₃22.7w%, NiO 7.0w%, hydrophobic Y zeolite 30w%.Catalyst specific surface 263m ²/ g, pore volume 0.311ml/g.Hydrophobic Y zeolite 30w%.Catalyst specific surface 266m ²/ g, pore volume 0.387ml/g.

Comparative example l～2:

Be oil type hydrocracking catalyst in two kinds of existing commerce (the Fushun Petrochemical Company catalyst plant is produced, the industrial trade mark 3901 and 3824), maximum is produced the boat coal and diesel oil is main, wherein 3901 also voluminous diesel oil.Two catalyzer contain zeolite all about 15%.3901 metal group becomes WO ₃22.3w%, NiO7.0w%, catalyst specific surface 241m ²/ g, pore volume 0.289ml/g, numbering D.3824 metal group becomes WO ₃21.1w%, NiO 6.7w%, catalyst specific surface 278m ²/ g, pore volume 0.291ml/g, numbering E.

The evaluating catalyst that above example obtains adopts the 200ml fixed-bed reactor, and one-stage serial once passes through flow process, an anti-Hydrobon catalyst of packing into, the two anti-hydrocracking catalysts of packing into.The evaluation processing condition are: anti-/ two anti-volume space velocity: 1.0/1.5; Hydrogen-oil ratio: 1500: 1; Reaction pressure: 14.7MPa, estimating with stock oil is triumph VGO, its main character sees Table 1, sees that the cyclic hydrocarbon of stock oil and aromaticity content are all higher, belongs to high aromatic hydrocarbons poor heavy raw material.One anti-temperature of reaction determines that according to the requirement that refining section generates oily nitrogen content＜10ug/g two anti-temperature of reaction can be adjusted according to keeping desired per pass conversion.The height of two anti-temperature of reaction is evaluated the activity of hydrocracking catalyst when reaching identical per pass conversion 60w% by contrast, and evaluate selectivity of catalyst according to the difference that product under the given transformation efficiency distributes, it is to obtain divided by the liquid yield that has transformed (summation of petroleum naphtha and intermediate oil) by the intermediate oil yield that middle distillates oil selectivity calculates.Table 2 has provided when handling Iranian VGO, the result of example 1～3 and comparative example 1～2.

Table 1. stock oil character

The stock oil title	The mixed oil of triumph	Saudi Arabia VGO	Iran VGO
				Density, the g/cm boiling range, ℃ carbon residue S, w% N, ppm BMCI value	0.9138 350～560 0.20 0.77 2266 44.6	0.9128 278～565 0.40 2.46 907 44.8	0.9046 268～528 0.07 1.69 1800 44.0

Table 2 technology assessment comparing result catalyst A B C D E temperature of reaction (℃) 380 373 365 375 374 middle distillates oil selectivities, % 84.6 82.9 79.3 83.8 74.5

Catalyzer that table 3 hydrocracking process of the present invention relates to and the contrast of reference catalyst product property

Catalyzer	Catalyst B	Reference catalyst D	Reference catalyst E
				The reformer feed virtue is dived w%	63.6	49.8	63.0
Boat coal aromatic hydrocarbons, w%	1.9	5.6	6.7
				Diesel cetane-number (actual measurement)	63.8	61.2	64.9
Tail oil BMCI value	10.8	16.8	11.0

Table 4 hydrocracking process tail oil of the present invention analytical data of mass spectrum

Stable hydrocarbon 98.7

Paraffinic hydrocarbons 51.3

Naphthenic hydrocarbon 47.4

Aromatic hydrocarbons 1.0

From table 2 comparison result is found out, the catalyzer that hydrocracking process of the present invention relates to use has shown good activity and middle distillates oil selectivity, D compares with reference catalyst, though under the suitable situation of activity, middle distillates oil selectivity is similar, but as seen from Table 3, hydrocracking process of the present invention relates to the petroleum naphtha virtue of the catalyzer acquisition of use and dives high, the diesel cetane-number height, boat coal aromaticity content is low, prove that the catalyzer that hydrocracking process of the present invention relates to use has stronger condensed-nuclei aromatics open loop ability owing to having high hydrogenation activity, thereby impel polycyclic aromatic hydrocarbons to transform to the lower boiling product, the catalyzer tail oil analytical data of mass spectrum that relates to use from the hydrocracking process of the present invention of table 4 as can be seen, it is low that hydrocracking process of the present invention relates to tail oil that the high aromatic hydrocarbons heavy hydrocarbon material of the catalyst treatment of use obtains total naphthenic hydrocarbon and aromaticity content, and corresponding paraffinicity is much higher, the hydrogenation of net product degree of saturation is big, illustrate that the catalyzer that hydrocracking process of the present invention relates to use has high hydrogenation activity and strong open loop ability, the inferior raw material of the high aromatic hydrocarbons of the suitable processing of these characteristics.This catalyzer that illustrates that also hydrocracking process of the present invention relates to use is particularly suitable for adopting and once passes through flow process, hold concurrently simultaneously and produce fine steam cracking system ethylene raw and catalytic reforming feedstock, productivity effect is more much higher than reference catalyst, thereby the handiness of production various objectives product is also just much bigger.And compare with reference catalyst E, the middle distillates oil selectivity of catalyzer that hydrocracking process of the present invention relates to use is high significantly.

Below further describe the characteristics of one-stage serial hydrocracking process of the present invention, comprise adaptability, the handiness of different schemes operation, and the high anti-nitrogen performance of catalyzer different heavy inferior raw materials with the catalyzer of example 2.The processing condition that example 4～6 is adopted are: anti-/ two anti-volume space velocity: 1.0/1.5 (except the example 6); Hydrogen-oil ratio: 1500: 1; Reaction pressure: 14.7MPa.Therefrom find out, hydrocracking process flexible operation mode of the present invention, strong to the adaptability of poor heavy raw material, anti-nitrogen ability is strong.

Example 4:

Choose a kind of domestic refinery and generally believe more unmanageable isolated island VGO and two kinds of import Middle East oil, Saudi Arabia VGO and Iranian VGO (stock oil character sees Table 1) are to investigate the adaptability to raw material of hydrocracking process of the present invention.As seen from Table 5, hydrocracking process of the present invention has good raw material adaptability, handles above-mentioned raw materials oil, has all showed good middle distillates oil selectivity.And when handling Saudi Arabia VGO, the feed nitrogen content that cracking zone bears reaches 35～40ppm.

The adaptability to raw material of table 5 hydrocracking process of the present invention

Stock oil	Isolated island VGO	Saudi Arabia VGO	Iran VGO
				Transformation efficiency, w%	～70	～70	～60
The treated oil nitrogen content, ppm	5～8	35～40	5～8
				Temperature of reaction, ℃	379	384	373
Middle distillates oil selectivity, % (W)	81.2	80.9	82.9

Example 5:

Because hydrocracking process of the present invention relates to the high reactivity of the catalyzer of use, therefore have the handiness that maximum is produced the boat coal, promptly only can maximum produce the boat coal by improving temperature of reaction.The result who handles Iranian VGO from table 6 finds out that the yield of boat coal increases obviously.

The handiness that table 6 hydrocracking process maximum of the present invention is produced the boat coal

Temperature of reaction, ℃	375	380
			Transformation efficiency, w%	～65	～80
Naphtha yield, the w% yield of coal that navigates, w% diesel yield, w%	11.1 33.5 19.6	16.0 41.6 22.0
			Middle distillates oil selectivity, %	82.7	79.9

Example 6:

Be to investigate the service performance under the severe condition of high-speed, the high nitrogen charging of cracking zone of hydrocracking process of the present invention, choose the Iranian VGO (main character: 312～508 ℃ of boiling ranges, sulphur 1.13w%, nitrogen 1200ppm) that another kind of Maoming petro-chemical corporation fetches.As seen from Table 7, hydrocracking process of the present invention still has good active and middle distillates oil selectivity under the average operating environment of feed nitrogen content up to 80ppm, format high throughput.

The service performance under severe condition of table 7 hydrocracking process of the present invention

Stock oil	Maoming Iran VGO
		The cracking zone volume space velocity, hr -1	1.67
The treated oil nitrogen content, ppm	80
		Temperature of reaction, ℃	385
Transformation efficiency, w%	～70
		Middle distillates oil selectivity, %	82.5

Example 7:

Be to investigate the effect of reaction pressure influence, hydrocracking process of the present invention is the Iranian VGO (main character: 312～508 ℃ of boiling ranges, sulphur 1.13w%, nitrogen 1200ppm) that fetches of Maoming petro-chemical corporation of use-case 6 still.Processing condition are: anti-/ two anti-volume space velocity: 1.0/1.5; Hydrogen-oil ratio: 1500: 1; Reaction pressure is respectively: 10.5MPa.As seen from Table 8, hydrocracking process of the present invention also has good active and middle distillates oil selectivity under lower pressure and high nitrogen charging.

The service performance under lower pressure of table 8 hydrocracking process of the present invention

Stock oil	Maoming Iran VGO
		The cracking zone volume space velocity, hr -1	1.5
The treated oil nitrogen content, ppm	100～120
		Temperature of reaction, ℃	389
Transformation efficiency, w%	～70
		Middle distillates oil selectivity, %	84.5

Claims (11)

1. A one-stage serial hydrocracking method for producing middle distillate oil. In the presence of hydrogen, feedstock oil is contacted with a catalyst, the system reaction pressure is 5-20MPa, the hydrogen-oil ratio is 100-5000, and the space velocity is 0.1-5.0hr ^-1 , the reaction temperature in the cracking section is 340-420°C, and it is characterized in that the catalyst used is composed of: (1) 5-40w% modified superhydrophobic Y zeolite; (2) 10-50w% macroporous amorphous silicon-alumina; (3 ) 10-40w% of Group VIB metal oxide and 1-10w% of Group VIII metal oxide; (4) 15-30w% of alumina binder; Among them, the modified superhydrophobic Y zeolite has the following characteristics: the SiO ₂ /Al ₂ O ₃ molar ratio is 5.0-25, the unit cell constant is 24.20-24.45×10 ^-10 m, the pore volume is 0.2-0.6ml/g, >20× The secondary pore volume of 10 ^-10 m accounts for more than 40% of the total pore volume, the specific surface area is 600-850m ² /g, the infrared acidity is 0.20-0.60mmol/g, the Na ₂ O content is less than 0.2w%, and the non-framework aluminum accounts for zeolite 10-80w% of the total aluminum, at 25°C, when P/P ₀ is 0.1, the water adsorption capacity is less than 5w%, the residual value of n-butanol adsorption experiment is less than 0.4, and the ion exchange capacity is less than 0.07. 2. According to the hydrocracking method of claim 1, it is characterized in that said catalyst is composed of: 10-35w% of modified superhydrophobic Y zeolite, 20-40w% of macroporous amorphous silicon-alumina, and 15-30w% of metal oxide of group VIB , 4-8w% of Group VIII metal oxide, 15-30w% of alumina binder. 3. The hydrocracking method according to claim 1, characterized in that the specific surface area of the catalyst is 150-350m ² /g, the pore volume is 0.25-0.45ml/g, and the infrared acidity is 0.25-0.55mmol/g. 4. The hydrocracking method according to claim 1 or 3, characterized in that the specific surface of the catalyst is 200-300m ² /g, the pore volume is 0.30-0.40ml/g, and the infrared acidity is 0.35-0.45mmol/g. 5. According to the hydrocracking method of claim 1, it is characterized in that the characteristics of the superhydrophobic Y zeolite are: the SiO ₂ /Al ₂ O ₃ molar ratio is 6.0 to 17, the unit cell constant is 24.25 to 24.35×10 ^-10 m, and the pores Volume 0.3～0.5ml/g; >20×10 ^-10 m secondary micropores account for more than 50%, specific surface area 700～800m ² /g, infrared acidity 0.25～0.50mmol/g, non-skeleton aluminum accounts for 10% of the total aluminum ~50w%. 6. The hydrocracking method according to claim 1, characterized in that said macroporous amorphous silicon-alumina contains 10-60w% silicon oxide, has a specific surface area of ^350-600m2 /g, a pore volume of 0.8-1.5ml/g, and an infrared acidity of 0.25 ~0.55mmol/g. 7. The hydrocracking method according to claim 1 or 6, characterized in that the macroporous amorphous silicon-alumina contains 20-40w% silicon oxide, has a specific surface area of ^400-550m2 /g, a pore volume of 0.9-1.4ml/g, and is infrared Acidity 0.30 ~ 0.50mmol/g. 8. The hydrocracking method according to claim 1 or 6, characterized in that the specific surface of the macroporous amorphous silicon-alumina is ^450-500m2 /g, the pore volume is 1.0-1.3ml/g, and the infrared acidity is 0.40-0.45mmol/g . 9. The hydrocracking method according to claim 1, characterized in that the group VIB metal is selected from Mo and/or W, and the group VIII metal is selected from Co and/or Ni. 10. The hydrocracking method according to claim 1, characterized in that the hydrocracking conditions are pressure of 7-18 MPa, hydrogen-to-oil ratio of 500-2500, space velocity of 0.5-2.0 hr ^-1 , and reaction temperature of cracking section of 350-410°C. 11. The hydrocracking method according to claim 1 or 10, characterized in that the hydrocracking conditions are pressure of 12-15 MPa, hydrogen-to-oil ratio of 1000-1500, space velocity of 0.8-1.5 hr ^-1 , and reaction temperature of cracking section of 360-400°C.