JP6719980B2 - Method for reactivating catalyst for fluidized catalytic cracking of iron deposit, reactivating device, fluid catalytic cracking method - Google Patents

Description

The present invention relates to a method for reactivating a fluid catalytic cracking catalyst having iron or nickel deposited on the surface thereof. More specifically, the present invention relates to a method for reactivating a catalyst for iron-based fluidized catalytic cracking that is simple, efficient, and has a small material loss.

In fluid catalytic cracking (hereinafter also referred to as FCC), heavy oil with low added value is contacted with a catalyst at high temperature to cause a cracking reaction and is converted into LPG, gasoline, kerosene, light oil, etc. with high added value. Is a process. As the catalyst used in fluid catalytic cracking (FCC) (hereinafter, also referred to as fluid catalytic cracking catalyst or FCC catalyst), for example, a solid acid catalyst containing zeolite and activated alumina as main components is used.

The FCC uses an upflow reactor (usually called a riser) and the feedstock is fed from the bottom of the reactor along with the FCC catalyst. Then, the fluidized catalyst is circulated between the reaction tower and the regeneration tower, and the catalytic cracking of the feed oil is performed.
The activity of FCC catalysts gradually decreases when used in fluid catalytic cracking, but the mechanism of deterioration is classified next.

1. Coke Degradation Although catalytic cracking reaction occurs in the riser, coke is also formed at the same time as the cracking reaction, and the coke covers the active sites of the catalyst and is rapidly deactivated during the reaction. The catalyst after being used for the reaction is transferred to the regeneration tower, and the coke is burnt and removed in the regeneration tower, so that the catalyst is regenerated and deactivated. For example, Patent Document 1: Japanese Patent Publication No. 2009-520601 discloses a method for improving a regenerating container.

2. Hydrothermal Degradation A high temperature steam atmosphere is generated in the regeneration tower at a high temperature of 650°C or higher, and water is generated when coke is further burned. Zeolite, which is the main active component of the FCC catalyst, loses its activity when exposed to such conditions, because its crystal structure is destroyed. Therefore, the activity of the FCC catalyst decreases as the residence time in the apparatus increases. This type of deactivation is non-renewable.

3. Metal Degradation Heavy feedstocks used in FCC include sodium, calcium, nickel, vanadium contained in crude oil, and metals such as iron and molybdenum mixed in crude oil during transportation and pre-process of FCC. include. Since neither metal can be removed in the regeneration tower and accumulated on the catalyst, the longer the FCC catalyst stays in the apparatus, the larger the amount of metal deposited, which adversely affects the catalyst activity. The main action is that sodium, calcium, vanadium, and molybdenum poison the active sites or destroy the zeolite crystal structure to deactivate it, while nickel and iron are largely distributed on the particle surface of the FCC catalyst and the deposition amount increases. It is to close the pores and reduce the activity.

When fluid catalytic cracking of heavy petroleum is carried out, among the metal deterioration, a phenomenon in which metals such as nickel and iron contained in the feed oil are deposited on the catalyst is particularly remarkable. These metals not only reduce the activity of the catalyst, but also the selectivity of the catalyst. That is, the dehydrogenation reaction of hydrocarbons is promoted, and as a result, the amount of hydrogen gas or coke which is not preferable as a product is increased, and the preferable amount of liquefied petroleum gas, gasoline or kerosene is decreased.

In order to avoid such a decrease in catalytic activity and a decrease in selectivity, in fluid catalytic cracking, a part of the catalyst in the circulation system is usually withdrawn regularly or constantly and exchanged with a fresh catalyst to keep the activity constant. The method of maintaining is adopted. However, when processing a heavy oil or a residual oil having a high metal content, it is necessary to remarkably increase the withdrawal amount of the catalyst, resulting in a very high cost. Further, the disposal of the extracted catalyst (hereinafter referred to as the equilibrium catalyst) becomes industrial waste, resulting in a higher cost for its treatment.

In view of this, a method of magnetically separating a magnetizing catalyst that has become a magnetized product by depositing a large amount of these metals has been proposed, paying attention to the magnetism of metals such as nickel and iron (Patent Document 2: US Patent). No. 5171424, Patent Document 3: Japanese Patent Laid-Open No. 2006-187771).
It has been proposed that the catalyst be slurried with a liquid containing an activator to remove contaminants that have clogged the pores (Patent Document 4: JP-A-2001-506538).

Japanese Patent Publication No. 2009-520601 US Pat. No. 5,171,424 JP, 2006-187771, A Special table 2001-506538 gazette

The method of magnetic separation as in Patent Documents 2 and 3 is a technique of selectively removing particles having a high iron concentration in the FCC catalyst, that is, low activity, by magnetic separation. The iron deposited on the FCC catalyst is not uniformly distributed throughout the catalyst, but is unevenly distributed between particles and within particles. The amount of iron deposited on the catalyst varies depending on the residence time in the apparatus. The longer the residence time of the catalyst particles, the higher the iron concentration, and the shorter the residence time, the lower the iron concentration. In addition, regarding the individual catalyst particles, the iron concentration is higher as it is closer to the particle surface, and the iron concentration is lower as it is closer to the center. That is, the surface is deactivated, but the interior is not deactivated.

Patent Documents 2 and 3 are methods for separating a low-activity catalyst that has stayed for a long time after being put into an actual device. When this method is used, the catalyst particles are separated and removed entirely, so that the inside of the catalyst particles having a low iron concentration is also removed. Therefore, since the effective catalyst portion inside is also discarded, there is a problem that the catalyst resources are wasted and the treatment cost is high because the amount of waste is large.

The inventors of the present invention have conducted intensive studies to solve such a problem, and as a result, during the FCC treatment, iron and nickel adhered to the periphery of pores on the catalyst surface, and the catalyst was deactivated. did.
Then, it was considered that the catalyst could be effectively reactivated and used if the iron and nickel adhering to the pores on the catalyst surface could be removed. However, the method of removing in a liquid using an activator as in Patent Document 4 is inefficient and too expensive because it involves steps such as in-liquid dispersion, solid-liquid separation, and drying.

Therefore, the present inventors have studied to develop a new method for reactivating a catalyst, and as a result, use an updraft to cause the deactivated catalyst particles to flow and bring the particles into contact with each other to abrade the particle surface. By doing so, it was found that iron and nickel existing around the surface pores can be separated and the FCC catalyst can be reactivated, and the present invention has been completed.

The structure of the present invention is as follows.
[1] A method of reactivating a deactivated catalyst by depositing iron on the surface of a fluid catalytic cracking catalyst for fluidization, the method comprising: the volume of the powder layer and V _0, the volume of the fluidized bed is formed when the in flowing the catalyst in updraft as V _M, V _M / V ₀ is 1.5 to 2.5 times range It is characterized in that the catalyst is brought into contact with each other to remove wear of iron accumulated on the surface to obtain a reactivated catalyst by making it flow at a temperature of 800° C. or lower for 0.5 to 30 hours, and obtain a reactivated catalyst. The pore diameter occupying the maximum pore volume in the range of 50 to 500 nm in the Log differential pore volume distribution measured by the mercury intrusion method for the catalyst, the catalyst for fluidized bed catalytic cracking of iron, and the reactivation catalyst is represented by the following formula 1. For reactivating catalysts for fluidized catalytic cracking of iron deposits satisfying the following conditions.
D _E /D _F +0.05 ≤ D _T /D _F ≤ 1.0 ... Formula 1
(A) _DF : Pore diameter (nm) occupying the maximum pore volume of the fresh catalyst
(B) D _E : Pore diameter (nm) occupying the maximum pore volume of the catalyst for fluidized catalytic cracking of iron deposits
(C) D _T : Pore diameter (nm) occupying the maximum pore volume of the reactivating catalyst

[2] For fluidized catalytic cracking of iron according to [1], characterized in that after the catalysts are contacted with each other, fine powder composed of iron deposits separated from the catalyst is collected and separated from the reactivating catalyst. Method for reactivating catalyst.

[3] A container in which a catalyst for fluidized catalytic cracking of iron deposits is filled, a separation part and a collector are provided above the container, and a charging port is provided in the lower part of the container to blow an upward airflow into the container. Ability to perform wear treatment of the catalyst for catalytic cracking of iron deposits in a container, separate the reactivated catalyst obtained and the iron deposits in the separation part, and collect fine powder of iron deposits in a collector For reactivating a catalyst for fluidized catalytic cracking of iron deposits equipped with.

[4] A fluid catalytic cracking apparatus equipped with a reaction tower, a separation unit, a regeneration tower, a catalyst reactivating device and a fractionator is used, and a feed oil and a catalyst for fluid catalytic cracking are charged into the reaction tower to obtain a raw material. After catalytic cracking of the oil, in the separation part, after separating the oil to be treated and the catalyst, the oil to be treated is fractionally fractionated by a fractionator, and the catalyst is regenerated in the regeneration tower by burning and removing coke. In the catalytic cracking method of circulating in the reaction tower,
The volume of the powder layer when the catalyst for fluidized catalytic cracking of iron deposition was filled in a container and the volume of the powder layer when the catalyst for fluidized catalytic cracking of iron deposition was filled in the container was set to V _0, and the catalyst filled from below the container was raised. the volume of the fluidized bed is formed when allowed to flow in a stream as V _M, the range of air updraft of V _M / V ₀ is 1.5 to 2.5 times, at a temperature 800 ° C. or less, 0 By fluidizing for 5 to 30 hours, the catalysts are brought into contact with each other to remove wear of iron deposited on the surface, and a fresh catalyst, a catalyst for fluid catalytic cracking of iron deposition, and the resulting reactivated catalyst are subjected to a mercury injection method. In the measured Log differential pore volume distribution, the reactivation catalyst satisfying the condition that the pore diameter occupying the maximum pore volume in the range of 50 to 500 nm is represented by the following formula 1 is returned to the regeneration tower together with the fresh catalyst, A method for fluid catalytic cracking of a feed oil, which comprises circulating the oil in a reaction tower.
D _E /D _F +0.05 ≤ D _T /D _F ≤ 1.0 ... Formula 1
(A) _DF : Pore diameter (nm) occupying the maximum pore volume of the fresh catalyst
(B) D _E : Pore diameter (nm) occupying the maximum pore volume of the catalyst for fluidized catalytic cracking of iron deposits
(C) D _T : Pore diameter (nm) occupying the maximum pore volume of the reactivating catalyst

By adopting the method of the present invention, it becomes possible to efficiently recover the activity of the catalyst deactivated by the iron deposit, and along with this, the amount of waste catalyst can be reduced and the fresh catalyst newly introduced. The usage amount of can be reduced.

1 shows a schematic diagram of a reactivation device according to the invention. The schematic process drawing of the catalytic cracking reaction of feedstock using the reactivating method according to the present invention is shown. The surface SEM photograph of the fresh catalyst before use is shown. The surface SEM photograph of an iron deposition catalyst is shown. The SEM photograph of the surface of the catalyst after an abrasion process is shown. 4 shows changes in pore volume before and after abrasion treatment.

Hereinafter, embodiments of the present invention will be described.
The method of the present invention is applied to a method for reactivating an iron deposited catalyst for fluid catalytic cracking in a fluid catalytic cracking process.

As a general fluid catalytic cracking process, first, heavy petroleum is contacted with a catalyst kept in a fluidized state in a fluid catalytic cracking unit to crack it, and then a mixture of cracked products, unreacted raw materials and catalyst. After being separated, the catalyst to which the carbonaceous substances and some heavy hydrocarbons adhere is subjected to combustion treatment in the regeneration tower. The catalyst regenerated in the regeneration tower is sent to the reaction tower, whereby the catalytic cracking reaction of the feed oil is continuously performed.

During the fluid catalytic cracking reaction, metals such as nickel, iron, cobalt, vanadium, and copper contained in the feedstock are deposited on the pores on the catalyst surface to close the pores and deactivate the catalyst. These metals come from contact with crude oil or transport storage and processing equipment. The “iron deposit” in the present invention includes deposits of metals such as nickel, cobalt, vanadium, and copper as well as iron.

Examples of the catalyst include commercially available FCC catalysts such as HMR, STW, DCT, ACZ, and CVZ (all are trademarks or registered trademarks of JGC Catalysts & Chemicals Co., Ltd.). The unused new catalyst is called fresh catalyst, and the catalyst extracted from the fluid catalytic cracker is sometimes called equilibrium catalyst.

The FCC catalyst is composed of a porous inorganic oxide containing faujasite-type zeolite, and includes, for example, silica, alumina, silica-alumina, silica-magnesia, alumina-boria, titania, zirconia, silica-zirconia, calcium silicate, calcium aluminum. Refractory oxides such as nates, and clay minerals such as kaolin, bentonite, and halloysite can be mentioned.

The average particle size of the catalyst is in the range of 40 to 100 μm, preferably 50 to 80 μm. If the average particle size of the catalyst is not within the above range, a suitable catalyst fluidized state may not be obtained.

The average particle size of the catalyst is screened at 20, 30, 45, 60, 75, 90, 105, 150 μm by a dry micromesh sieve method using a sieve particle size distribution measuring device (RPS-85EX manufactured by Seishin Enterprise Co., Ltd.). Then, the mass% of each classified sample is obtained, the cumulative mass% is plotted, and the 50 mass% value is taken as the average particle size. The bulk specific gravity of the catalyst is preferably 0.5 to 1.1 g/ml, and more preferably 0.6 to 1.0 g/ml. Even if the bulk specific gravity of the catalyst is not within the above range, a suitable fluidized state may not be obtained. The bulk specific gravity of the catalyst is measured based on UOP Method 254-65.

As a specific measuring method, the catalyst is calcined at 600° C. for 2 hours, cooled, poured into a 25 ml cylinder until the catalyst overflows, the overflowed catalyst is horizontally scraped off from the upper surface of the cylinder, and the mass of the catalyst is measured. Calculate by
Bulk specific gravity (g/ml)=catalyst mass (g)/25 (ml)

Such pores on the surface of the catalyst are clogged with "iron deposits", and the function is deteriorated or deactivated. The amount of iron deposit is appropriately selected according to the size and pore volume of the catalyst, and it can be judged from the composition of the feedstock reactant that is continuously treated whether or not the activity has decreased. Usually, the activity is lowered when the amount of iron deposits in the catalyst exceeds 0.5% by mass.

<1. Reactivation method>
In the present invention, the catalytic cracking catalyst on which iron is deposited is subjected to an abrasion treatment to reactivate the catalytic catalytic cracking iron deposit.

Specifically, the catalyst for iron-deposited fluid catalytic cracking was filled in a container, and the volume of the powder layer when the catalyst for iron-deposited fluid catalytic cracking was filled in the container was V _0, and the powder was filled from below the container. the catalyst volume of the fluidized bed is formed when allowed to flow in updraft as V _M, the rising air flow range of air V _M / V ₀ is 1.5 to 2.5 times, the flow of catalyst Let FIG. 1 also shows the concepts of volume and interface height. When V _M /V ₀ is a value much smaller than 1.5, the fluidity is low, so that the wear of the catalysts is suppressed and the removal efficiency of iron deposits is low, and the value is much larger than 2.5. If so, the catalyst becomes close to a turbulent flow state, and the probability of wear of the catalysts to each other is not preferable because the removal efficiency of iron deposits decreases.

The processing temperature at this time is 800° C. or lower, and the processing time is 0.5 to 30 hours. The lower limit of the temperature is not particularly limited and may be room temperature or lower temperature.
The catalyst filling amount in the container is appropriately selected according to the composition and size/shape of the catalyst and the size and shape of the container. As the container, a reactivating device according to the present invention described later is used.

Also, the volume V ₀ of the powder layer when the catalyst for fluidized catalytic catalytic iron deposition is filled in the container and the volume V _{M of the} fluidized bed formed when the catalyst is fluidized by the ascending air current can be calculated from the shape of the container. And can be calculated from the cross-sectional area of the bottom of the container and the heights of the interfaces between the powder layer/fluidized bed and the gas layer. Further, if there is no conical portion at the bottom of the container and the bottom surface cross-sectional area is constant, V _M /V ₀ can be calculated from the interface height. The interface height can be measured by constructing a part of the container from a transparent material (glass or acrylic) and visually drawing a line at the part of the container corresponding to the interface. The interface of the fluidized bed which is made to flow by the ascending air current is usually clear, but in the case of waviness, the interface height may be set so as to be an average value.

Under such treatment conditions, the catalyst flows and comes into proper contact, and the surface portion is abraded. According to such processing conditions, the catalysts are brought into contact with each other, and the iron deposits deposited in the pores on the surface are separated by wear.

By the abrasion treatment, deposits such as iron attached to the fine pores on the catalyst surface are removed, so that the fine pore diameter increases. As a measure of regeneration, the pore diameter occupying the maximum pore volume in the range of 50 to 500 nm in the Log differential pore volume distribution measured by the mercury intrusion method of the fresh catalyst, the catalyst for fluid catalytic cracking of iron deposition, and the reactivation catalyst is used. When _DF , _DE , and _DT are used, a reactivated catalyst having a pore size in the range represented by the following formula 1 is obtained, and the catalyst has a level of activity that can be used again in the catalytic cracking device. ..

D _E /D _F +0.05 ≤ D _T /D _F ≤ 1.0 ... Formula 1
This formula means that the pore diameter of the reactivated catalyst is obtained by improving the opening ratio of the pores of the iron-deposited catalyst by 5% or more.

The amount of wear is not particularly limited as long as the catalyst is reactivated, but may be in a range that does not exceed the remaining amount in the central portion. The worn portion corresponds to the “surface portion” of the deactivated catalyst, and the rest is the “center portion” of the catalyst.

Further, since a large amount of deposits of iron and the like are deposited in the pores of the surface portion, the iron deposits on the surface portion can be selectively removed when worn by the above method. Therefore, the removal of iron deposits is judged by monitoring the pore size as described above. As a rough guide, it is preferable to remove 1.0 mass% or more, preferably 1.5 mass% or more of iron deposited on the surface, but it is not limited to this because it depends on the pore diameter and the pore volume.

The particle size of the catalyst particles to be reactivated may not be substantially changed or may be slightly reduced by the abrasion treatment, but this is a particular problem because the reactivated catalyst is mixed with the fresh catalyst. There is no. In addition, since the blocked pores are recovered by removing the deposit, the pore distribution returns to the same level as the pore distribution of the fresh catalyst or the catalyst for catalytic cracking that has not been deactivated.

The wear-treated deposit and the catalyst are separated by a classifier such as a cyclone, and the recovered reactivated catalyst is reused as a catalyst for catalytic cracking, and the fine powder of the separated iron deposit is collected. And is separated from the catalyst reactivated by the abrasion treatment.

SEM photographs of the catalyst surface before and after the reactivation treatment are shown in FIGS. These are SEM photographs of the catalyst evaluated in the examples.
FIG. 3 shows a new catalyst (fresh catalyst), and FIG. 4 shows an iron deposited catalyst for catalytic cracking. FIG. 5 shows the reactivated catalyst, and the protrusions as shown in FIG. 4 due to iron deposition are observed in the pores on the surface of FIG. 3, but the protrusion disappears with the reactivation treatment. As a result, pores appear.

<2. Reactivating device>
The reactivating device according to the present invention is provided with a container in which a catalyst for fluidized catalytic cracking with iron accumulated therein is provided, a separating part and a collector in the upper part thereof, and a lower part for blowing an ascending air current into the container. It is equipped with a charging port, wears the catalyst for fluidized catalytic cracking of iron deposits in the container, separates the wear-treated catalyst from the iron deposits in the separation part, and consists of iron deposits in the collector. It has a function to collect fine powder.

A schematic diagram of such a reactivating device is shown in FIG. In the reactivating device of the present invention, the inside of the container in which the catalyst is caused to flow and comes into contact is the abrasion treatment part, and the upper part of the container is composed of the separation part and the collection part.
An inlet for blowing air is provided at the bottom of the container.

An air supply line is provided at the inlet, and if necessary, a compression means such as a compressor for adjusting the air to a predetermined linear velocity, a filter for removing dust and water in the air, and the like. A dryer, a valve, an orifice plate, etc. are provided.

The volume of the container is appropriately selected according to the size of the intended reactor, but the catalyst for iron deposition catalytic cracking is filled in the container, and the volume of the powder layer at that time is V ₀ , and the container is _Assuming that the volume of the fluidized bed formed when the catalyst filled from below is fluidized by an updraft is VM, the V _M /V ₀ is 1.5 to 2.5 times as high as the updraft of the air. There is no particular limitation as long as there is a space in which the catalyst can flow.

The separation part provided in the upper part of the container is configured so that the catalyst subjected to the abrasion treatment and the deposit can be separated by the ascending airflow and gravity, and for example, a cyclone type separation means provided with a predetermined inclination is provided.

A jig or a stopper for holding such a separating means may be provided on the outer surface or bottom of the container.
A publicly known dust collecting device such as a bag filter is used as the collecting portion provided above the separating means. It is also possible to use a dust collector having a magnetism or a charging mechanism. The catalyst reactivated by the abrasion treatment is separated by the separation unit and either stays in the abrasion treatment container as it is, or is recovered from a recovery passage provided separately on the side surface of the separation unit. The fine iron deposits pass through the separating section and are collected by the collecting section due to the ascending air current.

<3. Fluid catalytic cracking method for feedstock>
In the fluid catalytic cracking method for feedstock according to the present invention, the feedstock and the catalyst for fluid catalytic cracking are charged into a reaction tower to carry out catalytic cracking.

As the feedstock, an ordinary hydrocarbon feedstock, for example, hydrodesulfurization vacuum distillation gas oil (DSVGO) or vacuum distillation gas oil (VGO) can be used. Further, atmospheric distillation residue oil (AR), vacuum distillation Residual oils such as residual oil (VR), desulfurized atmospheric distillation residual oil (DSAR), desulfurized vacuum distillation residual oil (DSVR) and deasphalted oil (DAO) can also be used, and these may be used alone or in combination. Can be used. According to the present invention, a heavy oil having a boiling point range of 250° C. or higher at atmospheric pressure can be treated, but a heavy oil partially mixed with a light oil can also be used.

As the fluid catalytic cracking reactor used in the present invention, known ones can be used without particular limitation, and a fluid catalytic cracking apparatus equipped with a reaction tower, a separation part, a regeneration tower, a catalyst reactivating device and a fractionator is used. ..

The schematic process drawing of the catalytic cracking reaction of the heavy oil concerning FIG. 2 is shown.
In the present invention, the feed oil and the catalyst for fluid catalytic cracking are charged into a reaction tower and continuously contacted with the catalyst held in a fluidized state to perform the catalytic cracking of the feed oil.

The mixture of the oil to be treated (cracking products and unreacted substances) and the catalyst is sent to the separation section by catalytic cracking, and the oil to be treated and the catalyst are separated in the separation section, and then the oil to be treated is fractionated by a fractionator. To be done.

On the other hand, the separated catalyst becomes a regenerated catalyst by burning and removing coke in the regeneration tower, and is continuously circulated in the reaction tower. The catalyst separated by the separation unit may be subjected to a stripping treatment (not shown) if necessary.

Further, in FIG. 2, the newly added fresh catalyst is sent from the fresh catalyst hopper to the reaction tower via the regeneration tower, but the supply of the fresh catalyst is not limited to this.
In the present invention, the conditions of the fluid catalytic cracking reaction are not particularly limited and are generally widely used, and the reaction tower temperature, the regeneration tower temperature, the catalyst/oil ratio, the reaction pressure, the contact time and the like are set.

The timing of withdrawing the iron deposition catalytic cracking catalyst from the regeneration tower is determined by monitoring the reaction product composition, the catalyst activity, and the catalyst pore diameter and pore volume.
In the present invention, the iron deposition catalytic cracking catalyst extracted from the regeneration tower is filled in a container, and the volume of the powder layer when the iron deposition fluidized catalytic cracking catalyst is filled in the container from below the container is determined. V ₀ , where V _M /V ₀ is 1.5 to 2.5 times, with V _M being the volume of the fluidized bed formed when the catalyst filled from below the container is made to flow in an upward airflow With the rising airflow of the air, the catalyst is made to flow for 0.5 to 30 hours at a temperature of 800° C. or less to bring the catalysts into contact with each other, and the wear of iron deposits on the surface is removed. The wear removal separates the iron deposits, reactivates the catalyst, and returns it to the regeneration tower and circulates it to the reaction tower, with additional fresh catalyst added as needed. Further, since many deposits of iron and the like are deposited in the pores of the catalyst surface portion, the iron deposits on the surface portion can be selectively removed when worn by the above method. The amount of iron deposits removed is selected depending on the catalyst used, and is adjusted so as to obtain the pore diameter reactivated catalyst having the conditional expression represented by the above-mentioned formula 1.

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples.

[Examples 1 to 4, Comparative Examples 1 to 2]
Method for analyzing composition of metal components contained in catalyst (Fe, RE ₂ O ₃ , Al ₂ O ₃ , Ni, V, etc.)
The composition was determined using a fluorescent X-ray analyzer (RIX-3000, manufactured by Rigaku). A certain amount of sample and a flux are mixed, and this mixture is melted by a melting device to produce a glass disk. This glass disk is set in a fluorescent X-ray analyzer and the X-ray intensities of Ni-Kα and V-Kα are measured. The contents of various elements are measured using a calibration curve of concentration and X-ray intensity prepared in advance.

The average particle diameter of the dry micromesh sieve method of the catalyst, sieved at 20,30,45,60,75,90,105,150Myuemu, calculated the weight percent of each sample was classified, by plotting cumulative weight%, 50 The weight% value was defined as the average particle size.

The specific surface area (SA) of the catalyst specific surface area sample was determined by the BET one-point method using a specific surface area measuring device (Macsorb 1220 manufactured by Mountech Co., Ltd.). The sample was subjected to measurement after firing at 600° C. for 2 hours as a pretreatment. A mixed gas of N ₂ /He=30 vol%/70 vol% was used as a measurement gas, liquid nitrogen (-196° C.) was used to cool the sample cell, and a relative pressure was 0.3.

Bulk Specific Gravity of Catalyst The bulk specific gravity (ABD) of the sample was determined by calcining the catalyst at 600° C. for 2 hours, cooling, pouring the catalyst into a 25 ml cylinder until it overflowed, and scraping the overflowed catalyst horizontally from the top of the cylinder to determine the mass of the catalyst. It is measured and calculated by the bulk specific gravity (g/ml)=catalyst mass (g)/25 (ml).

Preparation Method of Fresh Catalyst A 35% by mass of ultra-stabilized Y-type zeolite (USY), 7.5% by mass of activated alumina as Al ₂ O ₃ , 20% by mass of silicic acid solution as SiO ₂ , and kaolin on a dry basis. After mixing 34.5% by mass, 3% by mass of white carbon as SiO ₂ and pure water to prepare a mixed slurry having a concentration of 30% by mass based on the catalyst, the mixed slurry is spray-dried to form fine spherical particles. Got The obtained fine spherical particles are washed to remove impurities such as sodium, and then ion exchange is performed using an aqueous solution of a rare earth metal (RE) chloride so that RE ₂ O ₃ in the particles is 1.1% by mass. did. After the ion exchange, it was dehydrated and dried at 150° C. to obtain a fresh catalyst A.

Preparation method of fresh catalyst B USY 24%, activated alumina 11% by mass, silicic acid solution 18.5% by mass, kaolin 46.5% by mass, and pure water are mixed, and the concentration is 30% by mass based on the catalyst. A fresh catalyst B was prepared in the same manner as the fresh catalyst A, except that the slurry was spray-dried and ion-exchanged so that the RE ₂ O ₃ content was 1.3% by mass.

Catalytic cracking catalyst for iron deposits Fresh catalyst A used in an FCC unit and extracted was designated as iron deposit catalyst A.
Similarly, the fresh catalyst B was used in the FCC apparatus, and the extracted one was used as the iron deposition catalyst B.

The wear process iron deposition catalytic cracking catalyst A, was charged into a reactivation device container, pouring air to the container, the volume ratio in the container (V _M / V _0), i.e., fluid for powder layer standing The sample was kept at 30° C. for 20 hours (Example 1), 2 hours (Example 2), and 0.25 hours so that the volume ratio (flowing/still standing) of the fluidized bed was 1.8. (Comparative Example 1) The fine powder on the surface portion of the sample which was made to flow and finely divided by abrasion was separated and collected.

FIG. 3 shows a surface SEM photograph of the fresh catalyst before use, FIG. 4 shows a surface SEM photograph of the iron deposition catalytic cracking catalyst, and FIG. 5 shows a surface SEM photograph of the catalyst after the abrasion treatment of Example 1.
In FIG. 3, the particle surface of the catalyst is smooth, and in FIG. 4, since a large amount of iron is deposited, protrusions containing iron as a main component appear on the surface of the catalyst particle. Then, by the abrasion treatment, the protrusions on the catalyst surface as shown in FIG. 5 disappear and the surface becomes smooth.

Further, the iron deposition catalytic cracking catalyst B is similarly filled in a reactivating device container, air is flown into the container, and the volume ratio of the catalyst in the container is the volume ratio of flowing time to stationary time (flowing time/static time). Of the sample that was finely pulverized due to abrasion by allowing the sample to flow for 20 hours (Example 3), 2 hours (Example 4), 0.25 hours (Comparative Example 2) so that the time of standing was 1.8. The fine powder on the surface was separated and collected.

FIG. 6 shows the Log differential pore volume distributions of the fresh catalyst B, the iron deposition catalytic cracking catalyst B, and the catalyst after abrasion treatment (Example 3). The Log differential pore volume distribution was measured by using a fully automatic multi-functional mercury porosimeter (POREMASTER 60-GT manufactured by Quantachrome Co., Ltd.) by a mercury porosimetry method to set about 0.4 g of the catalyst in the mercury porosimeter and degassing in vacuum. Then, the pressure was evaluated by injecting mercury in the range of 20 to 55,000 psi.

Thereby, the pore diameters D _F , D _E and D _T of each catalyst were evaluated.
The following reaction tests were performed using the catalysts reactivated as described above (Examples 1 to 4 and Comparative Examples 1 to 2).

Reaction test A reactor of a catalyst for fluid catalytic cracking test equipment (manufactured by Kayser: ACE-MAT, model R+) was charged with 9 g of the catalyst after abrasion treatment, the temperature inside the reactor was set to 520° C., and desulfurization atmospheric pressure was used as a feed oil. An oil in which the residual oil (DSAR) and the desulfurized vacuum distillation gas oil (DSVGO) were mixed at a ratio of 1:1 was supplied at an oil passage rate of 1.2 g/min for 75 seconds. At this time, the catalyst/feedstock mass ratio (Cat/Oil): 6.0.

Along with the start of the reaction, the product was recovered from the product recovery line, and then N ₂ gas was supplied after the end of the feed of the raw material oil to recover the product on the catalyst. The recovered product was separated and quantified into a product gas and a product oil by a cooler cooled to −15° C., and then each component contained in the product gas and the product oil was separated and quantified. Then, the reactor was heated to 700° C. in an air atmosphere, and while the coke remaining on the catalyst was burned, the coke was quantified by a carbon analyzer (1440D manufactured by Servomex).
The results are shown in Tables 2 and 3.

According to Tables 2 and 3, it is understood that the Fe concentration in the catalyst is lowered and the iron deposits on the catalyst surface are removed by performing the predetermined abrasion treatment. Then, it can be seen that the catalyst having such pore diameters satisfying the predetermined relational expression by such abrasion treatment has a high catalytic activity and a greatly improved gasoline yield.

That is, it was revealed that the activity of the catalyst deactivated by the iron deposit was efficiently recovered by the treatment of the present invention. Along with this, it is expected that the amount of waste catalyst can be reduced and the amount of fresh catalyst that has been newly introduced can be reduced.

Claims (4)

A method of reactivating an inactivated catalyst by depositing iron on the surface of a fluid catalytic cracking catalyst to reactivate the deactivated catalyst. the volume and V _0, the volume of the fluidized bed is formed when the in flowing the catalyst in updraft as V _M, range updraft of V _M / V ₀ is 1.5 to 2.5 times At a temperature of 800° C. or lower, the catalyst is brought into contact with each other for 0.5 to 30 hours to remove wear of iron deposited on the surface to obtain a reactivation catalyst. Conditions under which the pore diameter occupying the maximum pore volume in the range of 50 to 500 nm in the Log differential pore volume distribution measured by the mercury porosimetry of the deposited fluidized catalytic cracking catalyst and the reactivation catalyst is represented by the following formula 1. Method for reactivating a catalyst for fluidized catalytic cracking of iron deposits satisfying the requirements.
D _E /D _F +0.05 ≤ D _T /D _F ≤ 1.0 ... Formula 1
(A) D _F : pore diameter (nm) occupying the maximum pore volume of the fresh catalyst,
(B) D _E : Pore diameter (nm) occupying the maximum pore volume of the catalyst for fluidized catalytic cracking of iron deposits
(C) D _T : Pore diameter (nm) occupying the maximum pore volume of the reactivating catalyst The catalyst for fluidized catalytic cracking of iron deposits according to claim 1, characterized in that after the catalysts are contacted with each other, fine powders of iron deposits separated from the catalysts are collected and separated from the reactivating catalyst. Reactivation method. A vessel for the wear treatment section, which is filled with a catalyst for fluidized catalytic cracking of iron deposits, is equipped with a separation section and a collector above it, and an inlet for blowing updrafts into the vessel is provided at the bottom of the vessel for the wear treatment section. It is provided, and the iron deposition fluidized catalytic cracking catalyst is made to flow in the vessel of the abrasion treatment section to bring the catalysts into contact with each other to perform abrasion treatment on the catalyst surface , and to separate the obtained reactivation catalyst and iron deposits. A reactivation device for a catalyst for fluidized catalytic cracking of iron deposits, which has the function of separating fine particles of iron deposits by a collector and collecting them with a collector. Using a fluid catalytic cracking apparatus equipped with a reaction tower, a separation section, a regeneration tower, the catalyst reactivating apparatus according to claim 3 and a fractionator, a feed oil and a catalyst for fluid catalytic cracking are charged into the reaction tower. Then, the raw oil is catalytically cracked, and the oil to be treated and the catalyst are separated in the separation section, and then the oil to be treated is fractionally distilled by the fractionator, and the catalyst is burned and removed by the regeneration tower. After the regeneration, in the catalytic cracking method of circulating in the reaction tower,
The iron deposition fluid catalytic cracking catalyst was filled in a container of the wear section, the volume of the powder layer when filled with iron deposition fluid catalytic cracking catalyst into the container wear section and V _0, the container _Assuming that the volume of the fluidized bed formed when the catalyst filled from below is fluidized by an updraft is VM, the V _M /V ₀ is 1.5 to 2.5 times as high as the updraft of the air. At a temperature of 800° C. or lower for 0.5 to 30 hours to bring the catalysts into contact with each other to remove wear of iron deposited on the surface, to obtain a fresh catalyst, a catalyst for fluidized catalytic cracking of iron deposition, and the obtained A reactivated catalyst that satisfies the condition that the pore diameter occupying the maximum pore volume in the range of 50 to 500 nm in the Log differential pore volume distribution of the activated catalyst measured by mercury porosimetry satisfies the condition represented by the following formula 1 A method for fluid catalytic cracking of a feed oil, which comprises returning to a regeneration tower together with a catalyst and circulating it in a reaction tower.
D _E /D _F +0.05 ≤ D _T /D _F ≤ 1.0 ... Formula 1
(A) _DF : Pore diameter (nm) occupying the maximum pore volume of the fresh catalyst
(B) D _E : Pore diameter (nm) occupying the maximum pore volume of the catalyst for fluidized catalytic cracking of iron deposits
(C) D _T : Pore diameter (nm) occupying the maximum pore volume of the reactivating catalyst