JPS61235491A - Fluid catalytic cracking of heavy oil - Google Patents

Abstract

PURPOSE:To obtain gasoline and a medium fraction with high selectivity while suppressing lowering in activity of a fluid catalytic cracking catalyst as well as formation of dry gas and coke, by conducting fluid catalytic cracking of a heavy oil containing vanadium and nickel which act as a catalyst poison in the presence of a specific catalyst particle to immobilize the above metals. CONSTITUTION:A heavy oil containing nickel and vanadium in an amount of 0.5ppm in total is subjected to fluid catalytic cracking in the presence of a catalyst particle comprising 41-95wt% generally used fluid catalytic cracking catalyst particle and 5-59wt% alumina-magnesia catalyst particle to capture nickel and vanadium in the alumina-magnesia catalyst particle for immobilization. The magnesia content of the alumina-magnesia catalyst is preferably 2-90wt%. The generally used fluid catalyic cracking catalyst particle includes silica, alumina, amorphous silica, amorphous alumina, zeolite, kaolin, clay mineral, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a method for fluid catalytic cracking of heavy oil, and more specifically, it relates to a method for fluid catalytic cracking of heavy oil. 9 Heavy oil containing 0.5 ppm or more in total amount of both
Fluid catalytic cracking is carried out in the presence of catalyst particles at a constant t%, immobilizing the heavy metals, suppressing the decline in activity of the fluid catalytic cracking catalyst, and suppressing the production of dry gas (hydrogen, methane, ethylene, ethane) and coke. The present invention relates to a method for obtaining gasoline and middle distillates (boiling point range 200-850°C) with good selectivity.

Conventional technology Among the heavy metals contained in heavy oil, vanadium and chloride are the main catalyst poisons, but it has been revealed that there are considerable differences in the effects of these metals on catalysts. There is. That is, nickel is said to hardly reduce catalytic activity, but increases coke and hydrogen yields, and vanadium mainly destroys zeolite and reduces activity. Some catalysts that are resistant to the effects of such heavy metals have also been developed. For example, there is a method to improve vanadium resistance by increasing the zeolite content in the catalyst (Canadian Patent No. 1.089,890), but in this case, the octane number of the produced gasoline decreases due to the high hydrogen transfer reaction activity of the zeolite. There is a drawback that it does. There is also a report that a catalyst using a large pore matrix (US Pat. No. 8,944,482) has excellent vanadium resistance. However, these catalysts are not resistant to the action of nickel. Catalysts containing aluminum phosphate in the matrix (U.S. Pat. No. 4.222
, 896, U.S. Pat. No. 4,228,036) has been reported to have excellent metal resistance, but it has not been put into practical use yet because of its high cost.

Problems to be Solved by the Invention In conventional fluid catalytic cracking, petroleum hydrocarbons are cracked by contacting them with a catalyst to obtain a large amount of light components such as LPG and gasoline and a small amount of cracked light oil, which are then deposited on the catalyst. The resulting coke is removed by combustion with air and the catalyst is recycled and reused. Furthermore, conventionally, so-called distillate oils such as light gas oil (LGO) from atmospheric distillation columns, heavy gas oil (HGO), and vacuum gas oil (VGO) from vacuum distillation columns have been mainly used as feedstock oils. do not have.

However, in recent years, as crude oil has become heavier worldwide and the demand structure has changed in Japan, there has been a tendency for an excess of heavy oils from both the supply and demand perspective. It has become necessary to also target quality oil.

However, heavy oil containing distillation residue contains much higher amounts of metals such as dichloride, vanadium, iron, copper, and sodium than distillate oil, and these metals are not catalytic. is known to significantly inhibit the activity and selectivity of decomposition by depositing on the surface. In other words, as metals accumulate on the catalyst, the decomposition rate decreases, making it practically impossible to achieve the desired decomposition rate, while the amount of hydrogen and coke generated increases significantly, making it difficult to operate the equipment. At the same time,
The problem is that the yield of the desired liquid product is reduced.

Means for Solving the Problems The present invention provides a method for fluid catalytic cracking of heavy oil that solves these problems. When decomposing oil, it immobilizes the heavy metals, suppresses the reduction in activity of the fluid catalytic cracking catalyst due to the accumulation of heavy metals, and also uses dry gas (hydrogen,
The present invention relates to a method for obtaining gasoline and middle distillates (boiling point range 200 to 850°C) with good selectivity by suppressing the production of methane, ethylene, ethane) and coke.

That is, the present invention can process heavy oil containing nickel and vanadium in a total amount of 0.5 ppm or more using commonly used fluidized catalytic cracking catalyst particles of 41 to 95 weight and alumina/magnesia catalyst particles of 5 to 59 weight. The present invention relates to a process for fluid catalytic cracking of heavy oil, in which nickel and vanadium are captured and immobilized in the vanadium-gold-alumina-magnesia catalyst particles in the presence of catalyst particles consisting of a fine amount of 't-%.

The present invention will be explained in more detail below.

Fluid catalytic cracking as used in the present invention refers to a device having a reaction zone, a separation zone, a stripping zone, a catalyst regeneration zone, and a distillation zone. By continuous contact under pressure conditions, it is converted into light fractions such as gasoline and middle distillates (boiling point 200-350°C). - To give an example, the above-mentioned contact may be carried out in a fluidized bed of catalyst, or may employ so-called riser cracking in which both the catalyst particles and the raw material rise entirely in the tube. The mixture of reactants, unreacted raw materials, and catalyst that has undergone the catalytic reaction is generally sent to a stripping zone, where most of the hydrocarbons such as products and unreacted materials are removed. The catalyst with carbonaceous and some heavy hydrocarbons adhering to it is continuously extracted from the IJ wrapping zone and fed into the regeneration zone. In the regeneration zone (regeneration tower), the carbonaceous catalyst is subjected to oxidation treatment. Even in this regeneration zone, the catalyst is maintained in a fluidized state and is usually subjected to combustion treatment using high-temperature air. The catalyst that has undergone this oxidation treatment is a regenerated catalyst, in which carbonaceous substances and hydrocarbons deposited on the catalyst have been reduced. This regenerated catalyst is continuously recycled to the reaction zone. Generally, the operating conditions are reaction temperature 450~
550℃, pressure 0.5-8 kp/cdtG, catalyst regeneration temperature 550-750℃, catalyst/oil ratio 3-20 wt/w
t, 0.5-5 formula, CFR ((new raw material oil + circulating oil)/
new raw material oil) 1.0 to 2.0 vol/vol.

Heavy oil as used in the present invention refers to heavy metals such as nickel, vanadium, iron, and copper, containing at least nickel and vanadium in a total amount of 0.5 ppm J2U,
Preferably it is a hydrocarbon oil containing 5 ppm or more. Examples include crude oil, atmospheric distillation residue oil, vacuum distillation residue oil, solvent deasphalted oil, solvent deasphalted asphalt, sier oil, tar sand oil, and coal liquefied oil. In addition, distillate oil with a normal boiling point of 200°C or higher from atmospheric distillation or vacuum distillation containing 1% by weight or more of any of atmospheric distillation residue oil, vacuum distillation residue oil, solvent deasphalted oil, and solvent deasphalted asphalt, for example,
LGO (boiling point range 200-800℃), HGO (800℃
~500℃) and/or VGO (800~570℃)
A mixed oil can also be exemplified.

As the fluid catalytic cracking catalyst particles used in combination with the alumina/magnesia catalyst particles in the present invention, catalyst particles commonly used for cracking vacuum gas oil, atmospheric residual oil, or a mixture thereof can be used. For example, silica
Examples include catalyst particles made of one kind or a combination of 28i or more clay minerals such as alumina, amorphous silica/alumina, zeolite, and kaolin. The term zeolite herein refers to a natural or synthetic crystalline aluminosilicate or silicoaluminophosphate, and is preferably a porous material having an eight-dimensional framework structure and a uniform pore size within the range of about 4 to about xsA. Natural zeolites include gmelinite, shabasite, dachial dofutuite,
Any of clinoptilolite, faujasite, kiftite, borofluorite, levinite, erionite, sodalite, cancrinite, ferrierite, Brewster fluorite, offretite, nudafluorite, mordenite, etc. may be used, but faujasite is most preferred. Zeolite X and Y are synthetic zeolites.

A, L, ZK-4, B, E%F%HJ, M, Q, T, W
.

Z, 7/l/77, Heta, 28M type, Omega, 5AP
Any of O-type zeolites may be used, but Y-type and X-type zeolites or a mixture thereof are most preferred.

The particle size of the fluid catalytic cracking catalyst particles used in the present invention is 1
A range of 0μ to 200μ, particularly 20μ to 150μ is preferred.

The alumina/magnesia catalyst particles used in the present invention are synthetic products containing alumina (Altos)/magnesia (MgO) as main components or processed products from naturally occurring clay minerals, and have a magnesia content of 2 to 90%. i amount, preferably in the range of 10 to 50''! i%. When the magnesia content in the alumina-magnesia catalyst particles is less than 2 weight percent and when the magnesia content is more than 90 weight percent. None of them exhibits the characteristic effects seen in the present invention.The above alumina-magnesia catalyst particles can be prepared by any method. Examples thereof are as follows.Aluminum salt and Alumina/magnesia hydrogel +7 - is produced by reacting a mixed aqueous solution of magnesium salt with ammonia.
j, form. The type of salt at this time is not particularly limited, but chlorides, nitrates, and sulfates are preferred. Next, the hydrogel slurry is aged, passed through the mouth, washed with sufficient pure water, and dried at, for example, 110°C for a day and night.
Blow-fire at 600°C for 4 to 10 hours. 4 can also be made by the following method. Alumina is impregnated with an aqueous solution of a magnesium salt, filtered, dried at 110°C for a day and night, and then air-calcined at 500-600°C for 4-10 hours. In order to improve the abrasion resistance of the alumina/magnesia catalyst particles obtained in this way, even if one or more of silica sol, alumina sol, and clay minerals are added as a binder during the preparation of alumina/magnesia, the final alumina/magnesia As long as the binder content in the catalyst particles is 50% by weight or less, the effects seen in the present invention are not impaired. Any clay mineral can be used here as long as it has a binder effect, and examples include the following.

Kaolin, metakaolin, kaolinite, halloysite, di, kite, nacrite, montmorillonite, pennite.

The particle size of the alumina/magnesia catalyst particles used in the present invention is preferably in the range of 10 to 200 microns, particularly 20 to 150 microns. Further, the specific surface area of the catalyst particles is 50 to 800 m
'／? , especially 100-250 m'/S', pore volume 0.1-1.2 a:/f, especially 0.5-1. O.C.
t:/L? , the average pore size is 10~2ooXS especially 40
A range of ~150A is preferred.

The catalyst particles used in the method of the present invention are a mixture of commonly used wave catalytic cracking catalyst particles and alumina/magnesia catalyst particles. The mixing ratio of the fluid catalytic cracking catalyst particles and the alumina/magnesia catalyst particles is 41 to
The latter is 95% by weight, preferably 50-80% by weight, and the latter is 5-59% by weight, preferably 20-50% by weight. If the mixing ratio of the alumina/magnesia catalyst particles is less than 5% by weight, heavy metals such as nickel and vanadium contained in heavy oil cannot be sufficiently captured by the alumina/magnesia catalyst particles, and the present invention You can't expect the kind of effect you're seeing. Further, if the mixing ratio of the alumina/magnesia catalyst particles is more than 59% by weight, the alumina/magnesia catalyst particles themselves do not have decomposition activity, so the feedstock oil cannot be sufficiently decomposed, which is not preferable.

Equipment used per K for carrying out the catalytic cracking of the present invention,
That is, the fluid catalytic cracking apparatus having a reaction zone, a separation zone, a stripping zone, a catalyst regeneration zone, and a distillation zone is not particularly limited, but is preferably suitable for substantially cracking heavy oil. For example, the reaction zone is preferably equipped with a riser reaction zone to shorten the contact time between oil and catalyst and reduce the amount of coke produced, and the regeneration zone is preferably equipped with a riser reaction zone.
It is preferable to have equipment that can withstand high temperatures up to about 0°C or equipment that removes heat. Further, the operating conditions of the apparatus are not particularly limited, but for example, the reaction temperature is 450 to 550°C, the pressure is 0.
5-8 ky/cdlG, catalyst regeneration temperature 550-750
°C, catalyst/stop 8-20 virt/wt, contact time 0
．． Formula 5-5, CFR ((new feedstock oil + circulating oil)/new feedstock oil) 1.0-2. A range of Ovol/vol is preferred.

The light distillate as referred to in the present invention is a fraction having a boiling point range of 86 to 350°C, and is a fraction used for gasoline and middle distillates (kerosene, gas oil). The yield of the light fraction is 50
% or more, and K is 70 inches or more. The yield of the light fraction is calculated using the following formula, based on the substances at 850° C. or higher in the raw oil.

Light distillate yield (vol ratio)=The dry gas in the present invention refers to hydrogen and hydrocarbons having 1 to 2 carbon atoms (methane, ethane, ethylene).

The dry gas yield (scf/bbl) is generally 400
It is preferably 250 or less.

Functions and Effects Since the present invention simply mixes the fluidized catalytic cracking catalyst particles and the alumina/magnesia catalyst particles, the zeolite is not poisoned by magnesia and its activity is not reduced. In addition, heavy metals such as nickel and vanadium contained in heavy oil are deposited on both the fluid catalytic cracking catalyst particles and the alumina/magnesia catalyst particles, but the heavy metals deposited on the alumina/magnesia powder are immobilized and immobilized. As a result of activation, the relative amount of heavy metals that poison the fluid catalytic cracking catalyst is reduced, thereby suppressing the increase in hydrogen and coke yield and the decrease in activity due to metals accumulating on the catalyst. This not only reduces the load on the gas compressor, which is part of the cracked product distillation equipment, and the air blower that supplies air for coke combustion over the catalyst, but also increases the selectivity and selectivity of the liquid product. Increase yield.

Although the reason for the immobilization and inactivation of the heavy metals deposited on the alumina/magnesia catalyst particles is not fully clear, the following reasons may be considered. In the reaction tower, the 92 and Kel deposited on the alumina/magnesia catalyst particles become nickel oxide in the regeneration tower, but the ionic radius of nickel at this time is almost equal to the ionic radius of magnesium, so the nickel oxide has a spinel type. It easily penetrates or replaces solid solution in alumina and magnesia, which are oxides. The solid-dissolved nickel oxide is stable and will not be reduced again in the reaction tower, so that the dehydrogenation activity of nickel is lost and the generation of hydrogen and coke is suppressed. Vanadium is similarly oxidized to vanadium pentoxide in the regeneration tower. Vanadium pentoxide has a melting point of 674℃
It is said that the zeolite moves over the catalyst in the regeneration tower and reacts with the zeolite, destroying the crystal structure of the zeolite and reducing the catalytic activity. However, the vanadium pentoxide deposited on the alumina-magnesia catalyst particles reacts with alumina or magnesia to form a stable, high-melting-point composite oxide (for example, 8Mg0-VtOt) and is immobilized.

The specific method of using the present invention is to maintain the ratio of alumina/magnesia catalyst particles in the catalyst present in the fluid catalytic cracking device to be in the range of ~70% by weight, and to keep the amount of metal accumulated on the catalyst within a certain range. Regularly replenish the amount of normal fluid catalytic cracking catalyst, a mixture of normal fluid catalytic cracking catalyst and alumina/magnesia catalyst particles, or alumina/magnesia catalyst particles necessary to maintain the amount lost during operation. It is a good idea to remove the catalyst in use from the equipment. The amount of replenishment depends on the nature of the heavy oil to be treated, the metal content in the heavy oil and the metal accumulation capacity of the catalyst. By using the method of the present invention, it is possible to reduce the amount of metal accumulated on a conventional fluidized catalytic cracking catalyst, thereby reducing the amount of replenishment, which is of great economic benefit.

Example Example 1 Alumina-magnesia catalyst particles were prepared by the following method.

Dissolve 80kt of aluminum nitrate and 14kt of magnesium nitrate in 40kt of pure water.While vigorously stirring the above mixed solution in 4N ammonia water 8502, dissolve about 1.
Add over time. The resulting precipitate was aged at 90° C. for 4 hours under a basic condition of pH 10, filtered and washed, and dried with a spray dryer. This is air-calcined at 600° C. for 3 hours to obtain alumina-magnesia catalyst particles having an average particle size of 70 μm.

The thus obtained alumina/magnesia catalyst particles 3 kp and commercially available fluid catalytic cracking catalyst particles A (zeolite content 135
(weight ratio, silica/alumina matrix) 3 was mechanically mixed and impregnated with a mixed solution of nickel naphthinate and vanadium naphthinate to support 3,000 ppm of nickel and 6,000 ppm of vanadium. After that, steaming was performed at 770° C. for 6 hours (to achieve the same conditions as the equilibrium catalyst). 4 ky of steaming treated catalyst was packed into a circulating flow bench equipment under the following conditions: reaction temperature 490°C, regeneration tower temperature 630°C, normal pressure, catalyst (including alumina/magnesia)/hydraulic pressure 70, and raw material supply rate 700 yd/hr. Catalytic cracking reaction of Arabian Light atmospheric distillation residue oil was carried out. The reaction results are shown in Table 1. Table 2 shows the metal analysis results of Catalyst A and alumina/magnesia after the reaction.

Examples 2 to 3 and Comparative Example 1 A mixture of the alumina/magnesia catalyst particles prepared in Example 1 and Catalyst A at a weight ratio of 1:5 and 1:10 was treated in the same manner as in Example 1. The metal was supported and evaluated using a bench device. For comparison, evaluation was also conducted using only catalyst particles A. The results of these reactions are shown in Table 1.

Table 2 shows the metal analysis results of catalyst particles A and alumina/magnesia after the reaction.

These results show that when using catalyst particles A alone, the catalytic activity decreased significantly due to heavy metal poisoning, but by adding alumina/magnesia catalyst particles, the decrease in activity was suppressed. Based on the results of metal analysis, catalyst particles A
It can be seen that the metal is supported at a higher concentration on the alumina/magnesia catalyst particles.

Table-2 Patent Applicant Heavy Oil Countermeasures Technology Research Association Ceremony San San Patent Attorney Takeshi Saito 1.1,〃
〃 Ryoji Kawase ゛ Pa・−
25・

Claims (3)

[Claims] (1) The total amount of nickel and vanadium is 0.
Heavy oil containing 5 ppm or more is subjected to fluid catalytic cracking in the presence of commonly used catalyst particles consisting of 41 to 95% by weight of fluid catalytic cracking catalyst particles and 5 to 59% by weight of alumina/magnesia catalyst particles to produce nickel and vanadium. Alumina
A fluid catalytic cracking method for heavy oil characterized by trapping and immobilizing it in magnesia catalyst particles. (2) The method according to claim 1, wherein the magnesia content in the alumina-magnesia catalyst particles is 2 to 90% by weight. (3) Claim 1, wherein the commonly used fluid catalytic cracking catalyst particles are one or a mixture of two or more selected from silica, alumina, amorphous silica/alumina, zeolite, kaolin, and clay minerals. Method described.