JPS61127790A - Catalytic cracking of heavy hydrocarbon oil - Google Patents

Abstract

PURPOSE:Heavy hydrocarbon oil is brought into contact with a mixture of a granular catalyst containing crystalline alumina silicate and alumina particles containing phosphorus under cracking conditions to enable long-term high yield of gasolin even from low-quality oil. CONSTITUTION:A particle mixture consisting of (A) cracking catalyst particles containing crystalline aluminosilicate and alumina particles containing phosphorus (preferably the atomic ratio of P/Al is 0.01-0.14, average particle size is 20-80mu and bulk density is 0.5-1.2g/ml) at a weight ratio of 80/20-20/80 is brought into contact with heavy hydrocarbon oil under cracking conditions. The content of the crystalline aluminosilicate is more than 10wt%, preferably 20-40wt% in the particle mixture.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for catalytic cracking of heavy hydrocarbon oils, and more particularly to vanadium.

The present invention relates to a method of catalytically cracking a low-grade heavy hydrocarbon oil containing a large amount of metals such as nickel and iron in the presence of a mixture of crystalline aluminosilicate-containing cracking catalyst particles and phosphorus-containing alumina particles.

Conventionally, catalytic cracking of hydrocarbon oil for the purpose of producing gasoline is carried out using a cracking catalyst consisting of crystalline aluminosilicate dispersed in a matrix. As long as the raw material is a hydrocarbon oil with a relatively small amount of metal contaminants, even when the raw material oil is a heavy hydrocarbon oil, some success has been achieved. However, the worsening oil situation in recent years has created a situation where low-grade heavy hydrocarbon oil containing large amounts of vanadium, nickel, iron, etc. has to be catalytically cracked as is. When targeting heavy hydrocarbon oils, the conventional catalytic cracking methods described above do not necessarily yield good results.

In other words, when a low-grade heavy hydrocarbon oil containing a large amount of metal contaminants is treated with a conventional crystalline aluminosilicate-containing Clarakin catalyst, the cracking activity of the catalyst is only impaired by metal deposition. Instead, the dehydrogenation reaction is promoted due to the increased amount of metal deposited, and as a result, the amount of hydrogen and coke produced increases, resulting in a decrease in gasoline yield. When a large amount of metal is deposited on the catalyst, the crystalline aluminosilicate may undergo crystal destruction, further deteriorating the cracking activity.

For this reason, conventional methods have been used to catalytically crack heavy hydrocarbon oils containing large amounts of metals.

In order to keep the amount of metal deposited per catalyst particle low, methods have been adopted such as increasing the amount of cranking catalyst used, or mixing in used cracking catalyst with a relatively small amount of metal deposited. A method has also been adopted in which an antimony compound is added to the feedstock oil to suppress a decrease in cranking catalyst activity caused by metal deposition. However, these conventional methods are not necessarily successful due to the high conversion costs. Note that increasing the crystalline aluminosilicate content in the catalyst for the purpose of increasing cracking activity is not preferable because it promotes the by-production of coke and gaseous components and reduces the gasoline yield.

The present invention is a method that is different from the conventional methods described above, and is capable of catalytically cracking even low-grade heavy hydrocarbon oil containing a large amount of metal while maintaining a high gasoline yield over a long period of time. This method proposes that when catalytically cracking low-grade heavy hydrocarbon oil containing a large amount of metals, if phosphorus-containing alumina particles are mixed with a conventional cranking catalyst, This is based on the new findings that metal contaminants are preferentially captured by phosphorus-containing alumina particles, and that the cracking catalyst coexisting with these particles is significantly less poisoned by metal contaminants.

Accordingly, in the catalytic cracking method for heavy hydrocarbon oil according to the present invention, cracking catalyst particles containing crystalline aluminosilicate and alumina particles containing phosphorus are mixed in a ratio of 80/20 to 2.
It consists of contacting a particle mixture mixed in a weight ratio of 0/80 with a heavy hydrocarbon oil under cracking conditions.

In the present invention, as the crystalline aluminosilicate-containing cracking catalyst particles, any of various conventional cracking catalysts in which crystalline aluminosilicate is dispersed in a matrix made of a porous inorganic oxide can be used.
Most commonly, catalysts are used in which silica or silica-alumina is dispersed with ammonium ion exchanged or rare earth exchanged faujasite. The amount of crystalline aluminosilicate dispersed in the matrix ranges from 10 to 50% by weight for conventional catalysts, more typically from 20 to 4% by weight.
It is about 0% by weight.

However, in the present invention, since alumina particles are used together with the cranking catalyst, the amount of crystalline aluminosilicate is determined by considering the mixing ratio of both (this will be described later). It is possible to adjust the amount of crystalline aluminosilicate in the cranking catalyst in advance so that it is 10 to 50% by weight, preferably 20 to 40% by weight, based on the mixture.

The average particle diameter and bulk density of the phosphorus-containing alumina particles used together with the cranking catalyst particles are preferably comparable to those of the cranking catalyst used together, and in this sense, the phosphorus-containing alumina particles of the present invention Average particle size is 20~
It is suitable that the diameter is 80μ, preferably in the range of 40 to 70μ, and the bulk density is in the range of 0.5 to 1.2g#nQ. The oil absorption amount is preferably 0.2 cc/g or more. Such phosphorus-containing alumina particles can be produced by impregnating alumina particles with an aqueous solution of phosphorus compounds such as phosphoric acid or phosphates, and in this case, the alumina particles include, for example, an aqueous solution of sodium aluminate. Alumina hydrate is prepared by a neutralization reaction with an aqueous aluminum sulfate solution, by-product salts are removed from it by washing, and if necessary, the alumina hydrate is peptized with acid, and then this is spray-dried. , alumina particles obtained by firing can be used. It is also possible to use alumina particles obtained by firing aluminum hydroxide having an average particle diameter of 20 to 80 μm obtained by the Bayer method, which is advantageous in terms of low manufacturing cost. The amount of the phosphorus component contained in the alumina particles can be adjusted so that the atomic ratio of P/At of the phosphorus-containing alumina particles finally obtained is in the range of 0.01 to 0.14. P/AQj of phosphorus-containing alumina particles! When the A ratio is smaller than 0.01, the effect of phosphorus does not appear, and when the P/AQ atomic ratio is larger than 0.14.

This is not preferable because the amount of phosphorus in the phosphorus-containing alumina particles increases, which reduces the pore volume of the phosphorus-containing alumina particles and reduces oil absorption, and also because the bulk density tends to be larger than that of the cracking catalyst. In addition, when preparing phosphorus-containing alumina particles, if the alumina particles themselves have to be manufactured without using commercially available alumina particles, it is possible to impregnate the alumina particles with a phosphorus component after firing the alumina particles; In the present invention, the mixing ratio of the cranking catalyst and the phosphorus-containing alumina particles is 8 by weight.
It is necessary to be in the range of 0/20 to 20/80.

If the amount of phosphorus-containing alumina particles is less than this range, the metal contaminants in the feedstock cannot be sufficiently captured preferentially by the particles, and conversely, if the amount of cracking catalyst is less than this range, Naturally, the cracking activity decreases and the feedstock oil cannot be sufficiently catalytically cracked. Therefore, when carrying out the method of the present invention, the amount of metal contaminants contained in the feedstock oil must be taken into consideration. If the amount is large, increasing the proportion of phosphorus-containing alumina particles in the mixture of cranking catalyst and phosphorus-containing alumina particles will reduce the decrease in cranking activity that would occur with a relative decrease in the amount of Clarakin catalyst. It is possible to compensate by increasing the amount of crystalline alumina silicate dispersed in the cranking catalyst.

As the cranking conditions, the cranking conditions conventionally used in the art can be employed in the present invention, and typical examples of such cracking conditions are as follows. Reaction temperature: 460-540°C, WHSV
4~20hr-”, cat10il ratio 4~12
゜Also, in the catalytic cracking of hydrocarbons, the cranking catalyst, which has been inactivated by coke precipitation, is usually regenerated by carbon burning and reused in the cranking reaction. The method also uses conventional regeneration equipment and regeneration conditions to regenerate the used cranking catalyst and phosphorus-containing alumina particles, which can then be reused. This regeneration is usually carried out at 600-750°C.

The catalytic cracking method of the present invention is effective even when relatively high-grade heavy hydrocarbon oil with a low content of metal contaminants is used as feedstock oil, but the advantages of the present invention are most evident in the According to the method of the present invention, when low-grade heavy hydrocarbons containing a large amount of metal contaminants are catalytically cracked,
Gasoline can be obtained in high yield from heavy hydrocarbon oil with a total metal content of about 50 pp+m (metal equivalent). To explain this point further, the phosphorus-containing alumina particles used in combination with the cranking catalyst are more likely to contain metals such as vanadium and nickel than the crystalline aluminosilicate, silica, and silica/alumina that are the constituent components of the cracking catalyst. Metals in the feedstock oil are preferentially deposited on the alumina particles, and are inactivated by reacting with the alumina during exposure to high temperatures. Although this effect is also observed in alumina particles that do not contain phosphorus, the phosphorus component of alumina particles that contain phosphorus suppresses the dehydrogenation activity of metals, especially the action of nickel, which has high dehydrogenation activity. Compared to particles, by-products of coke, hydrogen, and other gaseous components can be significantly suppressed. On the other hand, from the perspective of the cranking catalyst, due to the coexistence of phosphorus-containing alumina particles, metal deposition on the catalyst is significantly reduced, thus maintaining the original catalytic activity of the cracking catalyst at a high level for a long period of time. It is possible.

The present invention will now be described in more detail with reference to Examples.

Example [Preparation of Crab King catalyst] Commercially available No. 3 water glass was diluted to give Sin, concentration 12.73vt.
% water-glass solution was prepared. This water-glass solution and concentration 25
% sulfuric acid was poured into the same container for 10 minutes at a rate of 20 Q/min and 5.6 Q/min, respectively, to obtain silica hydrosil. This silica hydrosil is mixed with 30% kaolin based on the weight of the final composition, and a 30vt% aqueous slurry of rare earth-exchanged Y-type zeolite (exchange rate 67%) is added to the silica hydrosil so that the amount of zeolite is 50% based on the weight of the final composition. The mixture was spray-dried, washed and dried to obtain a cracking catalyst A. In addition, by the same method as above, Table 1
A racking catalyst BE was prepared as shown in FIG. The composition and bulk density of each catalyst are shown below, and the average particle size of each catalyst was 57μ.

Table 1 [Preparation of phosphorus-containing alumina particles] Aluminum hydroxide with an average particle size of 70μ obtained by the Bayer method was calcined at 550°C for 3 hours to obtain a bulk density of 0.76g/
m Q, oil absorption 0.42cc/g, specific surface area (BET method) 175n? /g of alumina particles were obtained.

Next, part of this alumina particle was divided into three parts of 102 g each, one with a concentration of 9.7% and the other with a concentration of 34%.
The remaining one was made to absorb 40 g each of H, PO, and aqueous solutions with a concentration of 64%, dried, and then calcined at 550° C. for 3 hours to obtain the following three types of phosphorus-containing alumina particles.

Table 2 (Catalytic Cracking) The particle mixture subjected to the catalytic cracking reaction was conveniently separated into cranking catalyst and phosphorus-containing alumina particles as follows.

The above-mentioned cranking catalyst and phosphorus-containing alumina particles are each sieved to remove particles of 55μ or more for the cranking catalyst, and particles of 55μ or less for the phosphorus-containing alumina particles, and the remainder of each is immersed in 100% steam. 770℃
for 6 hours, and then calcined in air at 600°C for 1 hour. After that.

One type of cranking catalyst and one type of phosphorus-containing alumina particles were mixed at a predetermined ratio, and 4 g of the particle mixture was used to carry out the following catalytic cracking reaction.

to hydrotreated vacuum gas oil (DSVGO).

Nickel and vanadium content is 600ppm each
+ nickel naphthenate and vanadium naphthenate were added as the raw material oil, and the reaction conditions were a reaction temperature of 482°C, a space velocity of 16 hr -'', and a particle mixture/raw oil weight ratio of 3 for 75 seconds. After carrying out the decomposition reaction, the particle mixture in one reaction zone was exposed to air at 630 °C.
The reaction-regeneration operation was repeated 14 times by treating at °C for 50 minutes, then performing the above catalytic cracking reaction again.
Evaluate the catalytic cracking results in the second reaction, and further
At the end of the first reaction, the amount of metal deposited on the particle mixture was measured. The results are shown in Table 3.

Incidentally, the total amount of raw material oil flowed until the end of the 15th reaction was 20 g.

In addition, for comparison, catalytic cracking was carried out under exactly the same conditions and procedures as above, except that the following silica particles, used cranking catalyst, or alumina particles (without phosphorus) were used in place of the phosphorus-containing alumina particles. The reaction was carried out and the results shown in Table 3 were obtained.

[Silica particles]

Sin, a water-glass aqueous solution with a concentration of 12.73vt% and a concentration of 2
Silica hydrosil was prepared by mixing 5% sulfuric acid, which was spray-dried, washed and dried, and then calcined at 550°C for 3 hours to obtain an average particle size of 70μ.

Silica particles having a bulk density of 0.71 g/+mα were obtained. The silica particles were sieved to remove particles of 55 μm or less.

After processing the remainder in 100% steam at 770°C for 6 hours.

It was used in an experiment in which it was fired in air at 600°C for 2 hours.

[Used cranking catalyst]

In an actual device, a used cranking catalyst (average particle size 75 μ, bulk density! 0.81 g/m Q) was heated at 600°C.
It was baked for several hours and used in experiments. This used catalyst (Table 3
(indicated by SC) contained 235 ρpm of nickel and 438 ρPII+ of vanadium.

[Alumina particles]

The alumina particles used in the preparation of the phosphorus-containing alumina particles were sieved without being treated with an aqueous phosphoric acid solution to remove particles of 55 μm or less, and the remaining particles were treated in 100% steam at 770° C. for 6 hours.

It was baked in air for 1 hour and used for experiments.

(The following is a blank space) When evaluating the experimental results shown in Table 3, it should be noted that the total amount of metal deposition was approximately the same in each experiment. That is, in this example, the total amount of particles that come into contact with a total of 20 g of raw material oil is.

Since the amount is 4 g in each experiment, for example, in experiment Ha 6 in which the cranking catalyst and phosphorus-containing alumina particles were mixed at a weight ratio of 75/25, the amount of Ni and V deposited on the cracking catalyst were each 3 g x 1230XIO-' =
3.69mg and 3gX2230XlO-' = 6.6
It is calculated to be 9 mg. On the other hand, the amount of Ni and the amount of V deposited on the phosphorus-containing alumina particles are Lg x 11120, respectively.
0XIO-' = 8.20mg and 聰X5220X10
-'=5.22111g is calculated. Therefore, the total amount of deposited nickel in experiment Nα6 is 11.89 g, and the total amount of deposited vanadium is 11.91+*g, and these values are equal to the Ni amount of 4 in experiment &8 using only the cracking catalyst.
g X 2980XIO-' = 11.92+++g
, and V amount 4 g X 2990 X10-' = L1
．． It matches well with 96+sg.

Similarly, in experimental side 2, the cracking catalyst and phosphorus-containing alumina particles are mixed at a weight ratio of 50,750, so the total amount of deposited nickel and the total amount of deposited vanadium are calculated as follows, and the values are similar to experiment &8. Match.

Ni, 2gX 750X10-” +2gX4
960X10-" = 11.42mgV 2gX1
790X10-'+2gX4100X10-' =1
1.78mgThis relationship is the same in other experimental examples,
Taking this point into account, we note the experimental results shown in Table 3. 1. In the experiments Nci2, 3, 4, 6°7 according to the method of the present invention, the deposition of Ni and V on the cranking catalyst was small, and the deposition of Ni and V on the phosphorus-containing alumina was small. It can be seen that metal is preferentially deposited. Furthermore, the combined use of phosphorus-containing alumina particles did not have any adverse effect on the cracking reaction itself.

Rather, it originates from a decrease in the amount of metal deposited.

It can also be understood from the experimental results in Table 3 that the conversion rate and gasoline yield are improved, and the amount of hydrogen and coke produced is reduced.

Claims (1)

[Claims] 1. Cracking catalyst particles containing crystalline aluminosilicate and alumina particles containing phosphorus in a ratio of 80/2.
A method for catalytic cracking of heavy hydrocarbon oil, in which a mixture of particles mixed in a weight ratio of 0 to 20/80 is brought into contact with heavy hydrocarbon oil under cracking conditions. 2. The method of claim 1, wherein the amount of crystalline aluminosilicate contained in the particle mixture is at least 10%, based on the weight of the particle mixture. 3. The method according to claim 1, wherein the phosphorus-containing alumina particles have a P/Al atomic ratio of 0.01 to 0.14. 4. The average particle diameter of the phosphorus-containing alumina particles is 20
80μ and a bulk density of 0.5 to 1.2 g/ml.