JP3227298B2 - Coal liquefaction method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for liquefying coal, and more particularly to a method for liquefying coal including a hydrogenation step of hydrogenating coal in the presence of a catalyst.

[0002]

2. Description of the Related Art In recent years, there has been a strong demand for the development of liquid fuels that can replace petroleum due to resource and energy situations. In particular, since coal has abundant reserves, it is an important issue to establish a technology to efficiently liquefy coal and obtain liquid fuel. For this reason, various coal liquefaction methods have been proposed in the past, but a typical coal liquefaction method is to mix dried and pulverized coal with a solvent to form a slurry-like mixture, and to form a hydrogen gas under high temperature and pressure. Is added to cause a hydrogenation reaction to liquefy.

[0003] When a hydrogenation reaction (liquefaction reaction) of such coal is caused, a catalyst component contained in coal may be used without adding a catalyst depending on the kind of raw material coal. In order to increase the efficiency of the addition reaction, a method is used in which a catalyst is added to the slurry-like mixture and the mixture is subjected to a hydrogenation reaction, and the coal is hydrogenated in the presence of the catalyst and the solvent.

A catalyst for improving the efficiency of this hydrogenation reaction,
That is, as a catalyst for accelerating coal liquefaction (hereinafter referred to as a catalyst for coal liquefaction), conventionally, various molybdenum-based catalysts, zinc chloride, tin chloride or iron sulfide, iron sulfate, iron oxide, red mud, iron ore, etc. However, none of these catalysts is sufficient as a catalyst for coal liquefaction, and each of them has problems.

That is, the catalyst for coal liquefaction basically needs to be active as a catalyst (that is, excellent in catalytic function of increasing the hydrogenation reaction efficiency as a catalyst). It is necessary to be inexpensive and easy to obtain from an economic point of view, and it is necessary not to cause trouble in the coal liquefaction operation, etc. Among the above-mentioned catalysts, molybdenum-based catalysts are extremely expensive and have resource problems. It has a problem that corrosion of the equipment is apt to occur with a chloride catalyst such as zinc chloride, and it is inexpensive with a catalyst such as iron sulfide, iron sulfate, iron oxide, red mud, iron ore, etc. However, there is a problem that the activity as a catalyst (hereinafter referred to as catalyst activity) is not sufficient.

[0006] Among these catalysts, iron ore has insufficient catalytic activity, but has the advantage of being particularly inexpensive and easily available.
Often used as a catalyst for coal liquefaction. In this case, iron ore mechanically pulverized to reduce the particle size by mechanically pulverizing the iron ore (pulverized iron ore catalyst) is added to the slurry-like mixture as a coal liquefaction catalyst, and the hydrogenation reaction is carried out. And a method of hydrogenating coal in the presence of a crushed iron ore catalyst and a solvent. This is because, by using a pulverized iron ore catalyst having a small particle diameter, the dispersibility of the pulverized iron ore catalyst in a solvent coexisting in the slurry-like mixture is increased, and the contact efficiency with coal is increased, whereby the pulverization is performed. The aim is to increase the catalytic activity of iron ore catalysts.

[0007]

However, in a coal liquefaction method using such a crushed iron ore catalyst as a catalyst for coal liquefaction (hereinafter referred to as a conventional method), iron ore originally has a catalytic activity as described above. Since it is not enough, it is necessary to add a large amount of the pulverized iron ore catalyst to the slurry-like mixture. For example, in the case of the pyrite ore catalyst which is relatively high in the iron ore catalyst and is widely used, it is anhydrous. It is necessary to add an amount of 5 to 10% by weight based on ash coal (ratio to coal weight in terms of anhydrous ashless content). Therefore, the content of the crushed iron ore catalyst in the slurry-like mixture is large,
Therefore, a device that comes into contact with the flowing slurry-like mixture,
There is a problem that erosion is easily generated in the pipe portion, and particularly, damage due to erosion is easily generated in a slurry pump or a pressure reducing valve of a liquefaction reaction system. Furthermore, there is also a problem that the amount of iron ore pulverization required for obtaining a pulverized iron ore catalyst is large and the pulverization processing cost is high.

Here, if the addition amount of the pulverized iron ore catalyst is reduced to such an extent that these problems can be solved, the catalytic activity becomes insufficient, so that the efficiency of the liquefaction reaction is reduced and the yield of the oil component is reduced. There is a problem that it is low and insufficient. Therefore, a technique capable of solving these problems, that is, even if the catalyst addition amount is small enough not to cause the problems such as the erosion, the oil yield is not reduced, and a sufficient oil yield can be secured. The development of a coal liquefaction method is desired.

The present invention has been made in view of such circumstances, and an object of the present invention is to solve the problems of the conventional method (a method for liquefying coal using a pulverized iron ore catalyst as a coal liquefaction catalyst). It is an object of the present invention to provide a coal liquefaction method capable of securing the same oil content yield even with a small amount of catalyst as compared with the conventional method.

[0010]

In order to achieve the above object, a method for liquefying coal according to the present invention has the following configuration. That is, the method for liquefying coal according to claim 1 is a method for liquefying coal including a hydrogenation step of hydrogenating coal in the coexistence of a solvent and a catalyst, wherein coal is used as the catalyst. Liquefaction method.

The coal liquefaction method according to the second aspect is the coal liquefaction method according to the first aspect, wherein elemental sulfur or a sulfur compound is present together with the coal, the solvent, and the catalyst.

[0013] The coal liquefaction method according to claim 3 is the coal liquefaction method according to claim 1, which is used as a catalyst after the iron-manganese heavy stone is subjected to sulfidation treatment.

[0013]

The present invention has been studied to find a catalyst for coal liquefaction having a higher catalytic activity than a crushed iron ore catalyst. As a result, iron manganese heavy stone has a higher catalytic activity than a crushed iron ore catalyst.
The present inventors have obtained a new finding that an equivalent oil yield can be secured even with a small amount of catalyst added, and have been completed based on this finding.

That is, when crushed iron manganese spar (pulverized manganese spar) is used as a coal liquefaction catalyst, the manganese spar can act as a coal liquefaction catalyst.
Its catalytic activity is significantly higher than that of crushed iron ore catalysts, and therefore it is possible to obtain the same oil content yield even with a small amount of catalyst compared to crushed iron ore catalysts. Findings were obtained. Here, the iron-manganese heavy stone is a kind of tungsten ore, and refers to one in which iron heavy stone (FeWO ₄ ) and manganese heavy stone (MnWO ₄ ) form a solid solution.

The method for liquefying coal according to the present invention has been made based on such findings. In the method for liquefying coal including a hydrogenation step of hydrogenating coal in the coexistence of a solvent and a catalyst, in the method for liquefying coal, iron is used as the catalyst. Manganese heavy stone is used (the method for liquefying coal according to claim 1). That is, iron-manganese heavy stone is used as a coal liquefaction catalyst. Therefore, the catalytic activity of this iron manganese heavy stone is remarkably higher than that of the pulverized iron ore catalyst. Even if the amount of the catalyst is added, the same oil yield can be secured.

At this time, as the iron manganese heavy stone, as in the case of the iron ore catalyst, a pulverized one (crushed iron manganese heavy stone catalyst) is usually used as a coal liquefaction catalyst. This is because the catalytic activity of the crushed iron ore catalyst is enhanced when the catalyst is used by increasing the contact efficiency with the coal by increasing the dispersibility of the crushed iron manganese heavy stone catalyst in the solvent coexisting in the slurry mixture. Because it is good.

In the case of using such a crushed wolframite catalyst, the average particle diameter is desirably 10 μm or less. If the average particle diameter exceeds 10 μm, the effective surface area of the catalyst (outer surface area of catalyst particles per catalyst weight) is obtained. This is because the contact efficiency between the catalyst and the coal is low and the catalytic activity tends to decrease. In order to increase the effective surface area of such a catalyst and enhance the catalytic activity, the average particle diameter is 10 μm.
It is better to be smaller than m, and from such a point, it is desirable to be 5 μm or less, and particularly desirable to be 1 μm or less.

The reason why the catalytic activity of wolframite is remarkably higher than that of the crushed iron ore catalyst is not necessarily clear, but from the result of X-ray diffraction analysis of the catalyst, the following is considered. Can be

That is, after using manganese heavy stone as a catalyst for coal liquefaction, X-ray diffraction analysis and the like of the catalyst are performed, and as a result, firstly, heavy iron manganese acts as a catalyst for coal liquefaction in a sulfided state. I found out. Next, the X-ray diffraction patterns of the sulfided state and the sulfided manganese heavy stone show the broad diffraction peak of tungsten disulfide and the diffraction peak of unsulfided manganese heavy stone. The crystallite size of this tungsten disulfide was found to be quite small as estimated from the half width of the diffraction peak. In addition, the peaks of iron sulfide and manganese sulfide are not detected, and it is therefore presumed that there is a strong possibility that they exist in a state where the crystallite size is extremely small.

On the other hand, tungsten disulfide and iron sulfide are known to act as coal liquefaction catalysts.
Generally, the smaller the crystallite size, the higher the catalytic activity of the catalyst.

Based on the above, the reason why the catalytic activity of wolframite is remarkably higher than that of crushed iron ore catalyst is that wolframite is tungsten disulfide and iron sulfide which act as catalysts for coal liquefaction. Therefore, it is considered that the crystallite size becomes small and the catalytic activity becomes high.

The reason why the crystallite size is small as described above is considered as follows. That is, as described above, iron manganese heavy stone is made of iron heavy stone (FeWO ₄ ) and manganese heavy stone (MnWO ₄ ).
Since it is a solid solution with, it is a composite oxide of ternary metals (Fe, W, Mn), and as a result, sulfide (tungsten disulfide, iron sulfide and manganese sulfide) hardly aggregates.
Therefore, it is considered that tungsten disulfide, iron sulfide, and manganese sulfide were each dispersed and formed on the catalyst.

In the present invention, wolframite is sulfided as described above (ie, tungsten disulfide,
Since it acts as a coal liquefaction catalyst (as iron sulfide, manganese sulfide, etc.), it must be sulfided at the time of hydrogenation of coal. Regarding this sulphidation, if a relatively large amount of sulfur or a sulfur compound is contained in the raw coal that coexists with the manganese spar in the slurry mixture, the reaction of the sulfur or the sulfur compound with the sulphide manganese However, in order to sulphide iron manganese more sufficiently, it is preferable to add elemental sulfur or a sulfur compound to the slurry-like mixture and to coexist with the iron manganese heavy stone. Liquefaction method of coal described in 2). On the other hand, when the content of sulfur or the sulfur compound in the raw coal is small, if the elemental sulfur or the sulfur compound is added as described above and coexists with the manganese weighing stone, the manganese weighing stone can be sufficiently sulfided. Liquefaction method of coal described in 2). Furthermore, if the iron manganese spar is preliminarily sulfurized, it is added to the slurry-like mixture to be used as a catalyst, so that it can reliably function as a catalyst for coal liquefaction. Liquefaction method).

As the coal, subbituminous coal and bituminous coal can be used in addition to low-carbonized coal (coal with low carbonization) such as lignite. These are usually used after being dried to a water content of 15% or less, and then pulverized to a particle size smaller than about 60 mesh, whereby coal liquefaction can be advantageously performed.

The hydrogenation reaction conditions in the hydrogenation step are not particularly limited as long as the hydrogenation reaction occurs. Usually, the temperature is 350 to 500 ° C., the hydrogen partial pressure is 7 to 20 MPa, and the reaction time is: Ten
This is carried out under conditions of up to 120 minutes, according to which coal liquefaction can be advantageously carried out. The hydrogenated product obtained by the hydrogenation reaction may be recovered as an oil after separation of a solid such as a catalyst. However, usually, the oil after the separation is sent to a distillation column and a desired target product (heavy Oil, medium oil, light oil, etc.), and a part of the heavy oil is circulated and used as a circulating solvent in a slurry mixture preparation step.

As mentioned above, iron manganese heavy stone has remarkably high catalytic activity as compared with pulverized iron ore catalyst, so that even if a small amount of catalyst is added, the same oil content yield can be secured. When the target value of the yield is constant (same), the amount of catalyst addition required may be small. For example, the catalyst activity is relatively high among iron ore catalysts, and in the case of a frequently used pyrite ore catalyst, as described above, 5 to 5 on an anhydrous ashless coal basis.
Although 10 wt% is required, the addition amount of iron manganese heavy stone required to obtain the same oil yield as in this case is 0.
It may be 5 to 5% by weight.

[0027]

【Example】

(Example 1) First, manganese heavy stone (W: 57.5wt%, Fe: 1)
2.9 wt%, Mn: 2.6 wt%) to obtain a crushed wolframite having an average particle size of 2.6 μm. Then, in an autoclave having an inner volume of 0.3 liter, 60.0 g of 1-methylnaphthalene and 11.4 g of sulfur for sulfidation as a solvent for sulfidation were added, and 17.7 g of the pulverized manganese heavy stone was added, and an initial hydrogen pressure: 10 MPa, Sulfurization treatment of the pulverized manganese heavy stone was performed under the conditions of a reaction temperature: 450 ° C and a reaction time: 60 minutes. After a while
After the reaction product of the sulfidation treatment was filtered and washed with tetrahydrofuran, the residue was dried in vacuo to obtain sulfurized pulverized manganese heavy stone (hereinafter referred to as a pulverized manganese heavy iron sulfide catalyst).

Next, the sulfurizing catalyst and sulfur of the pulverized iron manganese heavy stone were added to Yaloon brown coal in Australia, and a brown coal liquefaction solvent was further added to obtain a slurry mixture. At this time, the amount of the sulfurized catalyst added to the pulverized wolframite was 3.0 wt% based on anhydrous ashless coal, and the amount of sulfur was 0.9 wt% based on anhydrous ashless coal.

The above slurry mixture was introduced into an autoclave (internal volume: 5 liters), and hydrogen initial pressure: 9 MPa,
A hydrogenation reaction (liquefaction reaction) was performed under a reaction temperature of 450 ° C. and a reaction time of 60 minutes. Thereafter, the obtained reaction product (hydrogenated product) was separated, distilled, and oil was separated by boiling range to obtain. As a result, the yield of a liquid fraction (oil) having a boiling point of C ₅ to 420 ° C. was 49.8 wt% based on anhydrous ashless coal.
Met.

Comparative Example 1 For comparison, a natural pyrite ore was pulverized to obtain a pulverized pyrite ore catalyst having an average particle size of 2.6 μm. This crushed pyrite ore catalyst was used in place of the sulfide catalyst of the crushed wolframite, and the preparation of a slurry mixture, coal liquefaction, and the like were performed by the same steps and conditions as in Example 1 except that sulfur was not added. Distillation was performed. As a result, the yield of the liquid fraction having a C ₅ to boiling point of 420 ° C. is as follows:
It was 24.8% by weight based on anhydrous ashless coal.

The catalyst addition amount (content of the pulverized pyrite ore catalyst in the slurry-like mixture) was 3.0 wt% as iron atoms based on anhydrous ashless coal. This is because the amount of the catalyst added is substantially equal to that of the first embodiment.

(Example 2) In preparing a slurry-like mixture, the addition amount of a sulfide catalyst of ground iron manganese deuterite (similar sulfide catalyst obtained under the same conditions as in Example 1) was changed as a parameter. Slurry-like mixtures having different addition amounts were obtained. Except for this point, preparation of a slurry-like mixture, liquefaction of coal, and distillation were performed by the same steps and conditions as in Example 1. Then, the relationship between the amount of the sulfurized catalyst added to the crushed wolframite and the yield of the liquid fraction having a C ₅ to boiling point of 420 ° C. was examined,
The yield of the liquid fraction having a C ₅ to boiling point of 420 ° C. was higher than that of Comparative Example 1.
When the amount of the catalyst added was the same as in the above, the amount of the catalyst added was 0.8 wt% based on anhydrous ashless coal.

From the comparison between Example 1 and Comparative Example 1, it was found that the amounts of the catalysts added were substantially the same (Example 1: 3.0 wt% as manganese heavy stone based on anhydrous ashless coal; Comparative Example 1: anhydrous ashless In the case of using sulfurized catalyst of pulverized iron manganese heavy stone (Example 1) when the sulfur atom is 3.0 wt% as iron atom on the basis of charcoal (Comparative Example 1), It can be seen that the yield of the liquid fraction at C ₅ to boiling point: 420 ° C. is extremely high.

From the comparison between Example 2 and Comparative Example 1, when the sulfurized catalyst of pulverized iron manganese heavy stone was used (Example 2), the sulfurized catalyst of pulverized pyrite ore was used (Comparative Example 1). compared to), C ₅ ~ bp catalytic amount of 420 when ℃ consisting of a yield identical liquid fraction is very small, can ensure the oil yield of the same (equivalent) with a smaller amount of catalyst loading You can see that.

Example 3 A pulverized manganese weighing stone catalyst (a pulverized manganese weighing stone catalyst not subjected to sulfidation treatment) was used in place of the pulverized manganese weighing stone sulfide catalyst to assist in preparing a slurry-like mixture. A relatively large amount of sulfur (2.7 wt% based on anhydrous ashless coal) was added as a catalyst, and a slurry mixture was prepared, coal liquefied, and distilled by the same steps and conditions as in Example 1 except for these points. As a result, the yield of the liquid fraction having a C ₅ to boiling point of 420 ° C. was 49.1 wt.
%Met. From the comparison between Example 3 and Example 1, the case where the crushed wolframite is added to the slurry-like mixture after the sulfurating treatment in advance (Example 1) and the case where the crushed wolframite is added to the slurry-like mixture are shown. In the case of sulfurization with the cocatalyst after the addition (Example 3), the yields of the liquid fractions are equal, and therefore, the degree of sulfidation and the degree of catalytic activity of both pulverized manganese heavy stones are equal. It is considered that

[0036]

According to the coal liquefaction method of the present invention,
Compared to the conventional method (a method for coal liquefaction using a pulverized iron ore catalyst as a catalyst for coal liquefaction), an oil yield equivalent to that of the conventional method can be secured even with a small amount of added catalyst. or,
When the catalyst addition amount is the same as the conventional method, the oil yield can be increased as compared with the conventional method.

Therefore, the liquefaction operation of coal having a high oil yield can be performed without causing problems such as erosion and a large amount of pulverization of the catalyst material, which are problems in the conventional method.

Continuing on the front page (73) Patent holder 000105567 Cosmo Oil Co., Ltd. 1-1-1, Shibaura, Minato-ku, Tokyo (72) Inventor Takao Kaneko 2-26-12 Moridai, Atsugi-shi, Kanagawa Prefecture (72) Inventor Koyama Tohru 124-1-101 Minori, Kakogawa-cho, Kakogawa-shi, Hyogo (72) Inventor Kazuharu Tazawa 385 Shinnobe, Beppu-cho, Kakogawa-shi, Hyogo (72) Inventor Jun Jun Imai 2-1-1, Satsukidaira, Misato-shi, Saitama (56) References JP-A-54-63103 (JP, A) JP-A-56-72079 (JP, A) JP-A-3-131683 (JP, A) JP-A-59-166586 (JP, A) Kaisho 59-155495 (JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) C10G 1/06 B01J 23/85 B01J 27/047

Claims (3)

(57) [Claims] 1. A coal liquefaction method comprising a hydrogenation step of hydrogenating coal in the coexistence of a solvent and a catalyst, wherein a manganese heavy stone is used as the catalyst. 2. The coal liquefaction method according to claim 1, wherein elemental sulfur or a sulfur compound is present together with said coal, solvent and catalyst. 3. The coal liquefaction method according to claim 1, wherein the manganese deuterite is used as a catalyst after the sulfidation treatment.