JP5399705B2 - Fluid catalytic cracking method - Google Patents

Description

  The present invention relates to a fluid catalytic cracking method, and more particularly to a fluid catalytic cracking method of a liquid product mainly composed of hydrocarbons obtained by Fischer-Tropsch synthesis.

  Conventionally, from the viewpoint of reducing the environmental load, clean liquid fuels and petrochemical raw materials that are low in sulfur content and aromatic hydrocarbon content and are environmentally friendly have been demanded. Therefore, in the petroleum industry, a Fischer-Tropsch synthesis method using carbon monoxide and hydrogen as raw materials (hereinafter abbreviated as “FT synthesis method”) is being studied as a method for producing clean liquid fuels and petrochemical raw materials. . According to the FT synthesis method, a liquid fuel base material and a petrochemical raw material having a high paraffin content and no sulfur content can be produced.

  However, the synthetic oil obtained by the FT synthesis method (hereinafter sometimes referred to as “FT synthetic oil”) has a high normal paraffin content and contains oxygen-containing compounds such as alcohol. It is difficult to use as a petrochemical raw material. More specifically, the synthetic oil has insufficient octane number for use as automobile gasoline, and low temperature fluidity for use as diesel fuel. In addition, oxygen-containing compounds such as alcohol adversely affect the oxidation stability of the fuel. Therefore, FT synthetic oil is used as a fuel feedstock or petrochemical feedstock after being subjected to hydrogenation treatment to convert normal paraffin in the synthetic oil to isoparaffin or to convert oxygenated compounds to other substances. Generally used.

Specifically, for example, when producing a diesel fuel base material, a kerosene base material, an aviation fuel base material, etc., a middle distillate rich in isoparaffin obtained by hydrocracking a heavy wax content of FT synthetic oil, In addition, the low temperature fluidity of the fuel base material is improved by appropriately mixing the middle distillate with an increased degree of paraffin isomerization obtained by hydroisomerizing the middle distillate of FT synthetic oil. (See Patent Documents 1 and 2). Also, gas oil and heavy fraction are separated from FT synthetic oil, the heavy fraction is catalytically cracked in a rising reactor using a large pore zeolite catalyst, and the gas oil fraction is recovered from the cracked product, A method of combining with the gas oil is disclosed (see Patent Document 3).
International Patent Publication No. 00/020535 Pamphlet French Patent Publication No. 2826971 International Patent Publication No. 05/118747 Pamphlet

  However, the fluid catalytic cracking treatment of FT synthetic oil by the conventional method has room for improvement in terms of destabilization of the treatment, yield of the resulting cracked product, and practical properties.

  More specifically, for example, in order to achieve heat balance, a coke yield of 5 to 7% is generally required. The decomposition reaction cannot be continued unless the amount of heat is supplemented.

The present invention has been made in view of such circumstances, and even when processing synthetic oil obtained by the Fischer-Tropsch synthesis method, fluid catalytic cracking can be stably processed over a long period of time. It aims to provide a method.

In order to solve the above-mentioned problems, the present invention provides a catalytic cracking method using a fluid catalytic cracking apparatus having a reaction zone, a separation zone, a stripping zone and a regeneration zone, which is a synthetic product obtained by a Fischer-Tropsch synthesis method. In the reaction zone of the fluid catalytic cracking apparatus, the first step of separating the product into a liquid product mainly composed of hydrocarbons and a mixture of unreacted hydrogen and carbon monoxide and a gas product. Using a catalyst containing 10 to 50% by mass of ultra-stable Y-type zeolite as a raw material oil containing the product, reaction zone outlet temperature 550 to 650 ° C., catalyst / oil ratio 10 to 40 wt / wt, reaction pressure 1 In the second step of treatment under the conditions of ~ 3 kg / cm ² G, the contact time of the raw material oil and the catalyst in the reaction zone of 0.1 to 1.0 second, and in the regeneration zone of the fluid catalytic cracking device, the first step A part or all of the mixture of unreacted hydrogen and carbon monoxide and gas products separated in step 1 is supplied as a heat source, and the catalyst used in the second step is converted to a temperature 620 to 690 of the catalyst rich phase in the regeneration zone. And a third step of treating under conditions of a regeneration zone pressure of 1 to 3 kg / cm ² G and an oxygen concentration of 0 to 3 mol% in the exhaust gas at the exit of the regeneration zone. .

  According to the fluid catalytic cracking method of the present invention, the synthesis product obtained by the Fischer-Tropsch synthesis method is a liquid product mainly composed of hydrocarbons, unreacted hydrogen and carbon monoxide, and gaseous production. The separated liquid product is subjected to fluid catalytic cracking. And by performing the fluid catalytic cracking process in the second step and the catalyst regeneration process in the third step, the coke shortage, which was a problem when performing the fluid catalytic cracking process of FT synthetic oil by the conventional method, The resulting process instability can be sufficiently suppressed, and the catalyst activity can be maintained at a high level over a long period of time. Therefore, when the hydrocarbon liquid product obtained by the FT synthesis method is subjected to fluid catalytic cracking, it can be stably treated over a long period of time while maintaining the heat balance.

  In the fluid catalytic cracking method of the present invention, the unreacted hydrogen and carbon monoxide separated in the first step and the gas product mixture are removed to remove the carbon monoxide and gas product mixture. The carbon monoxide and gas product mixture is preferably supplied to the regeneration zone in the third step.

  In the fluid catalytic cracking method of the present invention, the reaction zone is preferably a downward flow reactor.

  Moreover, in the fluid catalytic cracking method of this invention, it is preferable to spray raw material oil in the said reaction zone using the steam which is 2-6 mass% of the said raw material oil.

  In the fluid catalytic cracking method of the present invention, the difference between the temperature of the catalyst rich phase in the regeneration zone and the outlet temperature of the reaction zone is preferably within 150 ° C.

  In the fluid catalytic cracking method of the present invention, the delta coke on the catalyst is preferably 0.2 to 1.0 wt%.

  In the fluid catalytic cracking method of the present invention, the Si / Al ratio of the ultrastable Y-type zeolite is preferably 3 to 20 in terms of atomic ratio.

  The crystal lattice constant of the ultrastable Y-type zeolite of the catalyst is preferably 24.35． or less, and the crystallinity of the ultrastable Y-type zeolite is preferably 90% or more.

  Moreover, it is preferable that the alkali rare earth metal is introduced into the ion exchange site of the ultrastable Y-type zeolite.

  The active matrix of the catalyst preferably further contains silica alumina.

  Moreover, this invention provides the fuel for fuel cells characterized by containing the hydrogen obtained by the fluid catalytic cracking method of the said invention.

  The present invention also provides a gasoline characterized by containing a part or all of a fraction having a boiling point of 25 to 220 ° C. obtained by the fluid catalytic cracking method of the present invention or a hydride thereof.

  Moreover, this invention provides the diesel fuel characterized by including a part or all of the fraction of the boiling point 170-370 degreeC obtained by the fluid catalytic cracking method of the said invention.

  Moreover, this invention provides the liquefied petroleum gas characterized by containing the C3 or C4 hydrocarbon obtained by the fluid catalytic cracking method of the said invention.

  The present invention also provides a synthetic resin comprising propylene obtained by the fluid catalytic cracking method of the present invention as a constituent monomer.

  The present invention also provides a gasoline characterized by containing an ether obtained by reacting isobutylene obtained by the fluid catalytic cracking method of the present invention with methanol or ethanol.

  The present invention also provides a gasoline comprising a reaction product obtained by reacting butylene obtained by the fluid catalytic cracking method of the present invention with isobutane using an alkylation device.

  Moreover, this invention provides the gasoline characterized by containing the dimerization product of butylene obtained by the fluid catalytic cracking method of the said invention.

  ADVANTAGE OF THE INVENTION According to this invention, even when it is a case where the synthetic oil obtained by FT synthesis method is processed, the fluid catalytic cracking method which can be processed stably over a long term is provided.

  Hereinafter, preferred embodiments of the present invention will be described in detail.

  Hereinafter, preferred embodiments of the present invention will be described in detail.

  In the fluid catalytic cracking method of the present invention, first, a synthesis product obtained by a Fischer-Tropsch synthesis method using a synthesis gas mainly composed of hydrogen and carbon monoxide as a raw material is produced in a liquid state mainly composed of hydrocarbons. And a mixture of unreacted hydrogen and carbon monoxide and gaseous products (first step). In the present invention, the “gaseous product” refers to a hydrocarbon and hydrogen corresponding to 2 or less carbon atoms, and the “liquid product” refers to a product other than the gaseous product. . Separation of the liquid product and the gaseous product is generally performed by distillation industrially. Therefore, the liquid product and the gaseous product must be completely separated from each other, for example, the other is mixed into one of the liquid product and the gaseous product. However, in the present invention, the liquid product thus separated can be used without any problem.

As the FT synthesis method, a process known as a reaction process of FT synthesis using synthesis gas mainly composed of hydrogen and carbon monoxide, that is, a process such as a fixed bed, a supercritical fixed bed, a slurry bed, and a fluidized bed is used. be able to. The reaction conditions can be selected according to a conventional method. For example, the hydrogen / carbon monoxide molar ratio is 1.5 to 2.5, the reaction temperature is 200 to 280 ° C., and the gas space velocity is 1000 to 3000 h ⁻¹ . . A known catalyst can be used as the catalyst. For example, a catalyst in which an active metal such as iron or cobalt is supported on silica / alumina can be mentioned.

  In addition, as a method of separating a synthesis product obtained by the FT synthesis method into a liquid product mainly composed of hydrocarbons, and a mixture of unreacted hydrogen and carbon monoxide and a gas product, Distillation equipment used in petroleum refining can be used. The boiling range of the liquid product is preferably −50 ° C. or higher, more preferably 30 ° C. or higher.

  The liquid product mainly composed of hydrocarbons separated from the synthesis product may be used alone as a feed oil for fluid catalytic cracking. In addition to the liquid product, the fluid catalytic cracking feedstock oil may further contain a heavy oil obtained by distilling crude oil. Examples of such heavy oil include atmospheric residual oil, vacuum gas oil obtained by further distilling atmospheric residue, vacuum residual oil, hydrotreated oil, pyrolysis oil, and mixed oil thereof. Etc. The mixing ratio of the heavy oil is arbitrary, but is preferably 10 to 90% by mass, more preferably 30 to 50% by mass based on the total amount of the raw material oil.

Next, in the reaction zone of the fluid catalytic cracking apparatus, the reaction zone in the presence of a catalyst containing 10 to 50% by mass of ultrastable Y-type zeolite for the feedstock oil containing the liquid product mainly composed of hydrocarbons Fluidized catalytic cracking under conditions of an outlet temperature of 550 to 620 ° C., a catalyst / oil ratio of 10 to 40 wt / wt, a reaction pressure of 1 to 3 kg / cm ² G, and a contact time of raw material oil and catalyst of 0.1 to 1.0 second (Second step).

  Here, “fluid catalytic cracking” as used in the present invention refers to bringing a heavy feedstock oil into contact with a catalyst maintained in a fluidized state and decomposing it into light hydrocarbons mainly composed of gasoline and light olefins. Means.

  The fluid catalytic cracking apparatus (referred to as “FCC”) used in the present invention is not particularly limited as long as it has a reaction zone, a separation zone, a stripping zone and a regeneration zone.

  The reaction zone may be either a downflow reactor in which both catalyst particles and feedstock oil flow downward in the pipe, or an upflow reactor in which both catalyst particles and feedstock flow upward in the pipe. However, in the present invention, a downflow reactor is preferably used.

  The catalytic cracking catalyst used in the present invention contains 10 to 50% by mass, preferably 15 to 40% by mass, of ultrastable Y-type zeolite. As the ultrastable Y-type zeolite, those having an Si / Al atomic ratio of 3 to 20 are preferably used. The atomic ratio of Si / Al is more preferably 5 to 20, and further preferably 7 to 15. When the atomic ratio of Si / Al is less than 3, the catalytic activity becomes excessively large, and the amount of gas and LPG generated increases. On the other hand, if the Si / Al atomic ratio exceeds 20, the cost of the zeolite increases, which is not preferable in terms of economy.

  As the ultrastable Y-type zeolite, those having a crystal lattice constant of 24.35 or less and a crystallinity of 90% or more are preferably used. As the ultrastable Y-type zeolite, one obtained by introducing an alkali rare earth metal at the ion exchange site is preferably used.

  As a preferred embodiment of the catalyst used in the present invention, ultra-stable Y-type zeolite is formed into particles with a binder together with a filler which is a secondary active ingredient and can decompose large molecules of heavy oil, and a filler such as kaolin. The thing which was done is mentioned. Silica alumina is preferably used as the matrix component used in the catalyst of the present invention.

  In addition to the ultrastable Y-type zeolite, the catalyst may further contain a crystalline aluminosilicate zeolite having a smaller pore size than that of the Y-type zeolite, silicoaluminophosphate (SAPO), or the like. Examples of such zeolite include ZSM-5, and examples of SAPO include SAPO-5, SAPO-11, and SAPO-34. These zeolites or SAPOs may be contained in the same catalyst particles as the catalyst particles containing ultrastable Y-type zeolite, or may be contained as separate catalyst particles.

  Moreover, the exit temperature of the reaction zone in this invention is 550-650 degreeC as above-mentioned, Preferably it is 560-640 degreeC, More preferably, it is 590-630 degreeC. If the outlet temperature of the reaction zone is less than 550 ° C., the target products such as gasoline and light olefin cannot be obtained in high yield, and sufficient coke yield cannot be obtained. If it exceeds 650 ° C., thermal decomposition becomes prominent and the amount of dry gas generated increases. The “reaction zone outlet temperature” in the present invention is the outlet temperature of the reactor, and is the temperature before the decomposition product is rapidly cooled or separated from the catalyst.

  Further, the catalyst / oil ratio in the present invention is 10 to 40 wt / wt as described above, preferably 15 to 35 wt / wt, and more preferably 20 to 30 wt / wt. By increasing the catalyst / oil ratio to 10 to 40 wt / wt, it is possible to cope with coke shortage during synthetic oil treatment. In addition, when the catalyst / oil ratio is less than 10 wt / wt, a sufficient decomposition rate and coke yield cannot be obtained, and when the catalyst / oil ratio exceeds 40 wt / wt, the amount of catalyst circulation becomes large, and in the regeneration zone The catalyst residence time necessary for catalyst regeneration cannot be secured, and the regeneration of the catalyst becomes insufficient. The “catalyst / oil ratio” referred to in the present invention means the ratio between the catalyst circulation rate (ton / h) and the feed oil supply rate (ton / h).

The reaction pressure in the present invention are as described above 1 to 3 kg / cm ² G, preferably 1.2~2kg / cm ² G. When the reaction pressure is less than 1 kg / cm ² G, the difference from the atmospheric pressure becomes excessively small, and it becomes difficult to adjust the pressure with the control valve. In addition, when the reaction pressure is less than 1 kg / cm ² G, the pressure in the regeneration zone also decreases, and the container must be enlarged to ensure the residence time of the gas necessary for regeneration, which is economical. It is not preferable. On the other hand, when the reaction pressure exceeds 3 kg / cm ² G, the ratio of a bimolecular reaction such as a hydrogen transfer reaction to a decomposition reaction that is a monomolecular reaction increases. The “reaction pressure” in the present invention means the total pressure of the fluidized bed reactor. In addition, the “hydrogen transfer reaction” is a reaction in which olefins receive hydrogen from naphthene or the like and are converted to paraffin, which is a reaction that causes a decrease in the target light olefin, a decrease in the octane number of gasoline, and the like. .

  Moreover, the contact time of the raw material oil and the catalyst in the present invention is 0.1 to 1.0 seconds as described above, and preferably 0.3 to 0.9 seconds. If the contact time is less than 0.1 seconds, sufficient decomposition is not performed. On the other hand, if it exceeds 1.0 seconds, target organisms such as propylene and gasoline decrease due to excessive decomposition and hydrogen transfer. The “contact time between the feedstock and the catalyst” in the present invention refers to the period from the contact between the feedstock and the catalyst at the inlet of the fluidized bed reactor until the reaction product and the catalyst are separated at the outlet of the reactor. Means time.

  In the present invention, when introducing the raw material oil into the reaction zone, it is preferable to spray it using steam. It is preferable that the amount of steam at this time is 2-8 mass% with respect to raw material oil. If the amount of steam is less than 2% by mass relative to the feedstock oil, the particle size of the droplets at the time of spraying will not be sufficiently small, so that the droplets and the catalyst are not sufficiently contacted, and the reaction efficiency tends to decrease. . On the other hand, if it exceeds 8% by mass, the amount of water recovered in the product recovery zone, which will be described later, increases, which is economically undesirable.

  The mixture of the decomposition product, the unreacted material, and the catalyst that have been subjected to the catalytic cracking treatment in the reaction zone is sent to the separation zone, and the catalyst is separated from the mixture in the separation zone. As the separation zone, a gas-solid separation device using a centrifugal force such as a cyclone is preferably used. The catalyst separated in the separation zone is sent to the stripping zone, and most of hydrocarbons such as products and unreacted substances are removed from the catalyst particles in the stripping zone. On the other hand, a part of the raw material becomes heavier carbonaceous matter (coke) during the reaction and adheres to the catalyst, but the catalyst to which coke or heavier hydrocarbons adheres is regenerated from the stripping zone (regeneration zone ( To the regeneration tower).

In the regeneration zone, the catalyst from the stripping zone has a catalyst rich phase temperature of 620 to 740 ° C., a regeneration zone pressure of 1 to 3 kg / cm ² G, and an oxygen concentration of 0 to 3 mol% in the exhaust gas at the exit of the regeneration zone. Process under conditions. At this time, in order to replenish heat in the regeneration zone, a part or all of the unreacted hydrogen and carbon monoxide and gas product mixture separated in the first step is supplied to the regeneration zone as a heat source. As such a heat source, hydrogen is separated from a mixture of unreacted hydrogen and carbon monoxide and a gas product separated from a synthesis product obtained by the FT synthesis method, and then a mixture of carbon monoxide and a gas product is recovered in a regeneration zone. Is preferable because it can further suppress the hydrothermal deterioration of the catalyst.

  As described above, the temperature of the catalyst rich phase in the regeneration zone is 620 to 740 ° C, preferably 650 to 720 ° C, more preferably 660 to 710 ° C. When the regeneration zone liquid temperature is less than 620 ° C., the combustion of coke becomes insufficient. When the temperature exceeds 740 ° C., the deterioration of the catalyst is promoted, and more expensive members for withstanding the temperature of the catalyst rich phase in the regeneration zone need to be used as the material in the regeneration zone, which is economically undesirable.

  Further, the difference between the temperature of the catalyst rich phase in the regeneration zone and the reaction zone outlet temperature is preferably within 150 ° C, more preferably within 100 ° C. If this temperature difference exceeds 150 ° C., heat balance cannot be achieved. In the present invention, the “temperature of the catalyst rich phase in the regeneration zone” refers to the temperature immediately before the catalyst particles flowing in a rich state in the regeneration zone exit the regeneration zone.

The regeneration zone pressure is 1 to 3 kg / cm ² G as described above. When the regeneration zone pressure is less than 1 kg / cm ² G, the residence time of the gas necessary for regeneration is ensured, and the regeneration zone container becomes large, which is not economically preferable. In addition, when the regeneration zone pressure exceeds 3 kg / cm ² G, the pressure in the reaction zone increases accordingly, which is not preferable for an economy such as a hydrogen transfer reaction in the reaction zone.

  The oxygen concentration in the exhaust gas at the outlet of the regeneration zone is 0 to 3 mol%. If the oxygen concentration exceeds 3 mol%, excess air is sent to the regeneration zone using excess power, which is not economically preferable.

  The catalyst subjected to the above oxidation treatment is a regenerated catalyst, and coke and heavy hydrocarbons deposited on the catalyst are reduced by combustion. This regenerated catalyst is continuously circulated through the reaction zone. In some cases, the decomposition products are quenched immediately before or after the separation zone in order to suppress unnecessary thermal decomposition or excessive decomposition. The catalyst is heated by the amount of heat generated by the combustion of the carbonaceous material in the regeneration zone, and the heat is brought into the reaction zone together with the catalyst. The raw oil is heated and vaporized by this amount of heat. Further, since the decomposition reaction is an endothermic reaction, this amount of heat is also used as the heat of decomposition reaction. Thus, balancing the heat generation in the regeneration zone and the heat absorption in the reaction zone is an essential condition for FCC operation.

  As a countermeasure when the heat becomes excessive, there is a method of cooling the catalyst. This method is a method in which a part of the catalyst in the regeneration zone is extracted and heat is used for generating steam to take away the heat of the catalyst. As a countermeasure against heat surplus, there is a method in which the regeneration zone is set to two stages and the first regeneration zone is operated in an oxygen-deficient atmosphere.

  The upper limit of the amount of coke generated by catalytic cracking is generally determined for each FCC. For example, the permissible value of the coke amount is determined by the amount of heat that can be discharged out of the system by the above-described countermeasure for excess heat. In addition, the upper limit value of the amount of carbon dioxide generated by the location of the FCC may be determined, and the allowable value of the coke amount is limited by the numerical value. Normally, the FCC is operated with as much oil flow as possible and as high a decomposition rate as possible, and as a result, operation is performed with the upper limit of the coke amount.

  In the present invention, the amount (% by mass) of coke produced per feedstock is referred to as “coke yield”. The coke yield in this invention becomes like this. Preferably it is 2-10 mass%, More preferably, it is 5-9 mass%, More preferably, it is 6-8 mass%. When the coke yield is less than the above lower limit, the amount of carbon monoxide and gaseous products supplied to the regeneration zone to supply heat necessary for the reaction increases, which is economically undesirable. On the other hand, if the coke yield exceeds the above upper limit, the amount of heat generated in the regeneration zone becomes excessively large, which is not preferable because it is subject to operational restrictions such as a decrease in decomposition rate and a decrease in oil flow rate.

Moreover, the coke yield in the present invention is preferably 0.2 to 1.5 mass%, more preferably 0.3 to 1.0 mass%. If the coke yield is less than 0.2% by mass, the heat required for the reaction tends to be insufficient. On the other hand, if the coke yield exceeds 1.5% by mass, the amount of heat generated in the regeneration zone becomes excessive, which is not preferable because it is subject to operational restrictions such as a reduction in decomposition rate and a reduction in oil flow rate. In the present invention, “delta coke” on the catalyst means a value represented by the following formula.
(Delta coke) = (Amount of coke attached to catalyst before regeneration (mass%)) − (Amount of coke remaining on the regeneration catalyst (mass%))

  The FCC in the present invention preferably further comprises a decomposition product recovery zone. An example of such a product recovery zone is a decomposition product recovery facility that separates and recovers a decomposition product based on a boiling point or the like. The decomposition product recovery equipment includes a plurality of distillation towers, absorption towers, compressors, strippers, heat exchangers and the like. As will be described later, each of the various fuel base materials and petrochemical raw materials can be more reliably recovered by the decomposition product recovery facility.

  As described above, according to the fluid catalytic cracking method of the present invention, even when a synthetic oil (a liquid product containing hydrocarbons as a main component) obtained by the FT synthesis method is treated, it can be stably produced over a long period of time. It becomes possible to process.

  In addition, since the fluid catalytic cracking method of the present invention uses a hydrocarbon liquid product obtained by FT synthesis as a raw material, it is excellent in terms of energy security and carbon dioxide reduction. And is very useful when producing raw materials for petrochemical products.

  For example, hydrogen obtained by the fluid catalytic cracking method of the present invention can be used as a fuel for fuel cells.

  The fraction having a boiling point of 25 to 220 ° C. obtained by the fluid catalytic cracking method of the present invention can be used as a gasoline base material. Here, a fraction having a boiling point of 25 to 220 ° C. may be partially used as a gasoline base material, or all may be used as a gasoline base material, and a fraction having a boiling point of 25 to 220 ° C. may be hydrogenated. The resulting hydride can be used as a gasoline base material.

  Further, a fraction having a boiling point of 170 to 370 ° C. obtained by the fluid catalytic cracking method of the present invention can be used as a diesel fuel base material. Here, the fraction having a boiling point of 170 to 370 ° C. may be partially used as a diesel fuel base material, or may be entirely used as a diesel fuel base material.

  The hydrocarbon having 3 or 4 carbon atoms obtained by the fluid catalytic cracking method of the present invention can be used as a liquefied petroleum gas base material.

  Propylene obtained by the fluid catalytic cracking method of the present invention can be used as a constituent monomer of a synthetic resin.

  In addition, ether obtained by reacting isobutylene obtained by the fluid catalytic cracking method of the present invention with methanol or ethanol can be used as a gasoline base material.

  A reaction product obtained by reacting butylene obtained by the fluid catalytic cracking method of the present invention with isobutane using an alkylation apparatus can be used as a gasoline base material.

  The dimerized butylene obtained by the fluid catalytic cracking method of the present invention can be used as a gasoline base material.

  EXAMPLES Hereinafter, although this invention is demonstrated more concretely based on an Example and a comparative example, this invention is not limited to a following example at all.

[Example 1]
Fischer-Tropsch synthesis is performed using a catalyst in which an active metal such as iron or cobalt is supported on silica / alumina under the conditions of a hydrogen / carbon monoxide molar ratio of 2: 1, a reaction temperature of 300 ° C., and a gas space velocity of 2000 h ^−1. It was. The resulting synthesis product was separated into a hydrocarbon liquid product and a mixture of unreacted hydrogen, carbon monoxide and gaseous products using a distillation apparatus.

  Next, fluid catalytic cracking was performed using the separated hydrocarbon liquid product as a raw material oil. As the fluid catalytic cracking reaction apparatus, an FCC pilot apparatus (manufactured by Xytel) having a reaction zone (adiabatic downflow reactor), a separation zone, a stripping zone and a regeneration zone was used. Moreover, the catalyst prepared as follows was used as a catalytic cracking catalyst.

21550 g of a diluted solution of JIS No. 3 water glass (SiO ₂ concentration = 11.6%) was dropped into 3370 g of 40% sulfuric acid to obtain a silica sol having a pH of 3.0. To this total amount of silica sol, 3000 g of ultrastable Y-type zeolite (manufactured by Tosoh Corporation: HSZ-370HUA) and 4000 g of kaolin were added, kneaded, and spray-dried with hot air at 250 ° C. The spray-dried product thus obtained was washed with 50%, 0.2% ammonium sulfate, dried in an oven at 110 ° C., and calcined at 600 ° C. to obtain a catalyst. The content of ultrastable Y-type zeolite in this catalyst was 30%. At this time, the bulk density of the catalyst particles was 0.7 g / ml, the average particle diameter was 71 μm, the surface area was 180 m ² / g, and the pore volume was 0.12 ml / g.

  The catalyst obtained as described above was quasi-equilibrium by 100% steaming treatment at 800 ° C. for 6 hours before being supplied to the apparatus. At this time, the equipment scale is inventory (total amount of catalyst) 2 kg, feed amount 1 kg / h, fluid catalytic cracking reaction conditions are catalyst / feed oil ratio 20, reaction zone outlet temperature 600 ° C., contact time 0.5 seconds. The gas linear velocity of the downward flow reactor was 4 m / s. In the reaction zone, the feedstock was supplied to the reaction zone by spraying the feedstock using steam corresponding to 5% by mass of the feedstock. According to the reaction heat calculated from the enthalpy difference between the raw material and the product, the amount of coke required for the heat balance was 8.5%. The actual coke yield was 7.5%, and the insufficient heat was compensated as follows. The unreacted hydrogen and carbon monoxide separated from the synthesis product of the FT synthesis and the unreacted hydrogen are removed from the gas product mixture, and the resulting carbon monoxide and gas product mixture is put into the regeneration zone. It was supplied as a heat source.

  Table 1 shows the conversion rate from feedstock to cracked products, yield of cracked products, delta coke, and research octane number of the gasoline obtained in the above catalytic cracking reaction. In Table 2, the yields of the decomposition products are all the mass ratios of the decomposition products with respect to the raw oil, and C1 represents methane gas and C2 represents ethane gas (the same applies hereinafter).

[Example 2]
A catalyst was prepared in the same manner as in Example 1, and this catalyst and a commercially available additive for improving octane number (GRACE Davison: Olefinsmax) were used in combination so as to be 20% of the inventory (total amount of catalyst and additive). The catalytic cracking reaction was carried out in the same manner as in Example 1 except that it was used. Table 1 shows the conversion rate from the raw material oil to the cracked product, the yield of the cracked product, delta coke, and the research octane number of the obtained gasoline.

[Comparative Example 1]
Catalytic cracking was performed in the same manner as in Example 1 except that Middle Eastern desulfurization VGO was used as the raw material oil. Table 1 shows the conversion rate from the raw material oil to the cracked product, the yield of the cracked product, delta coke, and the research octane number of the obtained gasoline.

[Comparative Example 2]
Example 2 except that Middle Eastern desulfurization VGO was used as the feedstock. The catalytic cracking was carried out in the same manner as above. Table 1 shows the conversion rate from the raw material oil to the cracked product, the yield of the cracked product, delta coke, and the research octane number of the obtained gasoline.

[Comparative Example 3]
Using the same equipment scale, catalyst, and feed oil as in Example 1, the catalyst / feed oil ratio in the operating conditions was changed to 5.5, the reaction zone outlet temperature was changed to 500 ° C., and the contact time was changed to 2 seconds. A decomposition reaction was performed. Table 1 shows the conversion rate from the raw material oil to the cracked product, the yield of the cracked product, delta coke, and the research octane number of the obtained gasoline.

  From the results shown in Table 1, in Examples 1 and 2, the FT synthetic oil was decomposed at a high yield by performing decomposition under the above reaction conditions using a catalyst containing ultrastable Y-type zeolite. It can be seen that oil and light olefin are obtained. Moreover, in Example 2, it turns out that a light olefin with a higher added value can be further increased by using a combination of a catalyst containing an ultrastable Y-type zeolite and a commercially available additive for improving octane number. Moreover, the heat balance was able to be maintained by supplying the gas product of FT synthesis to the regeneration tower. Although the temperature of this experimental apparatus can be adjusted by an external heater, the commercial apparatus does not have an external heater. Therefore, if the heat balance is not maintained, the reaction temperature also decreases, and stable operation cannot be maintained.

  Further, compared with Comparative Examples 1 and 2 using Middle Eastern desulfurized VGO, in Examples 1 and 2, the decomposition rate is higher by 10% or more, and the by-product dry gas and coke yield are somewhat suppressed. Moreover, the yields of the target products, light olefins and cracked gasoline, are also high.

  On the other hand, Comparative Example 3 corresponds to the case where the FT synthetic oil is decomposed under the same conditions as those of the conventional FCC in which the catalyst / feed oil ratio is 5.5, the reaction zone outlet temperature is 500 ° C., and the contact time is 2 seconds. In this case, the delta coke was about the same as in Examples 1 and 2, but the coke yield was remarkably low, and in general, about 5 to 7% of coke was required to achieve heat balance. It can be seen that the decomposition reaction cannot be continued under the present reaction conditions unless the amount of heat is compensated. In Comparative Example 3, the output of the electric external heater was adjusted to compensate for the shortage of heat and the operation was continued.

  In addition, compared with Comparative Example 3, it can be seen that the cracked gasoline obtained in Examples 1 and 2 has a high octane number.

Claims (17)

A catalytic cracking method using a fluid catalytic cracking apparatus having a reaction zone, a separation zone, a stripping zone and a regeneration zone,
A first step of separating a synthesis product obtained by the Fischer-Tropsch synthesis method into a liquid product mainly composed of hydrocarbons and a mixture of unreacted hydrogen and carbon monoxide and a gas product;
In the reaction zone, the raw material oil containing the liquid product is converted to a catalyst containing 10 to 50% by mass of ultrastable Y-type zeolite, the outlet temperature of the reaction zone is 550 to 650 ° C., and the catalyst / oil ratio is 10 A second step of treatment under conditions of ˜40 wt / wt, reaction pressure of 1 to 3 kg / cm ² G, and a contact time of 0.1 to 1.0 seconds between the raw material oil and the catalyst in the reaction zone;
In the regeneration zone, a part or all of a mixture of unreacted hydrogen and carbon monoxide and gas products separated in the first step is supplied as a heat source, and the catalyst used in the second step is And a third step of treatment under conditions of a catalyst rich phase temperature of 620 to 690 ° C., a regeneration zone pressure of 1 to 3 kg / cm ² G, and an oxygen concentration of exhaust gas at the regeneration zone outlet of 0 to 3 mol%. A fluid catalytic cracking method characterized by the above.   Unreacted hydrogen and carbon monoxide separated in the first step and a mixture of gas products are removed from the mixture of unreacted hydrogen to obtain a mixture of carbon monoxide and gas products. The fluid catalytic cracking method according to claim 1, wherein a mixture of materials is supplied to the regeneration zone in the third step.   The fluid catalytic cracking method according to claim 1 or 2, wherein the reaction zone is a downward flow reactor.   The fluid catalytic cracking method according to any one of claims 1 to 3, wherein the raw oil is sprayed into the reaction zone using steam corresponding to 2 to 6% by mass of the raw oil.   The fluid contact method according to any one of claims 1 to 4, wherein the difference between the temperature of the catalyst rich phase in the regeneration zone and the outlet temperature of the reaction zone is within 150 ° C.   The catalytic cracking method according to any one of claims 1 to 5, wherein the delta coke on the catalyst is 0.2 to 1.0 wt%.   The fluid catalytic cracking method according to any one of claims 1 to 6, wherein the ultrastable Y-type zeolite has an Si / Al ratio of 3 to 20 in terms of atomic ratio.   The fluid catalytic cracking method according to any one of claims 1 to 7, wherein the ultrastable Y-type zeolite has a crystal lattice constant of 24.35Å or less and a crystallinity of 90% or more. The fluid catalytic cracking method according to any one of claims 1 to 8 , wherein the active matrix of the catalyst further contains silica alumina. A method for producing a fuel base material for a fuel cell, comprising a step of obtaining hydrogen by the fluid catalytic cracking method according to any one of claims 1 to 9 . A process for producing a gasoline base material comprising a step of obtaining a part or all of a fraction having a boiling point of 25 to 220 ° C or a hydride thereof by the fluid catalytic cracking method according to any one of claims 1 to 9. Way . A method for producing a diesel fuel base material, comprising a step of obtaining a part or all of a fraction having a boiling point of 170 to 370 ° C by the fluid catalytic cracking method according to any one of claims 1 to 9 . A method for producing a liquefied petroleum gas base material comprising a step of obtaining liquefied natural gas using a hydrocarbon having 3 or 4 carbon atoms by the fluid catalytic cracking method according to any one of claims 1 to 9. . A method for producing a synthetic resin , comprising: a step of obtaining propylene by the fluid catalytic cracking method according to any one of claims 1 to 9 ; and a step of obtaining a synthetic resin containing the propylene as a constituent monomer. . A gasoline base material comprising: a step of obtaining isobutylene by the fluid catalytic cracking method according to any one of claims 1 to 9 ; and a step of reacting the isobutylene with methanol or ethanol to obtain an ether. Manufacturing method . Obtaining a butylene by fluid catalytic cracking process according to any one of claims 1 to 9 gasoline, characterized in that it comprises a step of Ru and said butylene and isobutane are reacted with alkylation unit A method of manufacturing the material . A method for producing a gasoline base material comprising a step of obtaining a dimerization product of butylene by the fluid catalytic cracking method according to any one of claims 1 to 9 .