JPS6183288A - Liquefaction of coal - Google Patents

Abstract

PURPOSE:To increase catalystic activity of iron ore and liquefy coal with a high conversion rate at a lower temp. and under a lower pressure than in the conventional process, by using as catalyst for coal liquefaction, a low grade iron ore washed with water or immersed in water for a long time and dried. CONSTITUTION:A low grade iron ore contg. 0.3-3wt% Ni, 10-50wt% Fe and 0.5-10wt% Cr and having an Al2O3/SiO2 ratio of below 3 and a specific surface area of about 50-100m<2>/g (pref., e.g., laterite) is washed with water or immersed in water for a long time, followed by drying. The treated low grade iron ore which is free from deleterious substances and has increased catalytic activity is used as catalyst for hydrocracking of coal in a solvent at high temp. and under high pressure in the presence of hydrogen. The method makes it possible to perform liquefaction of coal with a high conversion ratio at a lower temp. and under lower pressure than in conventional processes and prevent lowering of quality of product, for use of sulphur as cocatalyst is not required at all or its amount can be minimized.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for liquefying coal by hydrocracking it by adding hydrogen to the coal in a solvent at high temperature and pressure under a coal liquefaction catalyst.

(Prior art) Coal liquefaction is a method in which coal is thermally decomposed by adding hydrogen under high temperature and high pressure, thereby obtaining liquid hydrocarbons. Along with using water,
This creates harsh reaction conditions.

Conventionally, various catalysts have been used to alleviate the reaction conditions, and the above reaction has been carried out under the catalyst. The catalyst used for this purpose is desired to have liquefaction activity, be inexpensive, and be able to be supplied in large quantities, but no conventional catalyst can satisfy all of these requirements.

For example, the H-coal method is a method in which 1 to 10 times of a Co-Mo catalyst is added to coal, but this catalyst is expensive and therefore poses an economical problem.

A method of using iron ore as an iron-based catalyst is also known. □This method has the advantage of being able to supply a large amount of catalyst because iron ore is inexpensive, but on the other hand, this catalyst was said to have low liquefaction activity. Therefore, in order to increase the liquefaction activity, sulfur or its compounds are added as promoters. However, when sulfur or its compounds are used in large amounts, the sulfur content is contained in the liquefied oil, causing problems such as deterioration of its quality.

(Objective of the Invention) The present invention improves the liquefaction activity of an inexpensive iron ore catalyst, and improves the liquefaction of coal by using a lower temperature and pressure condition than the conventional method, without using a co-catalyst, or using a small amount of co-catalyst. An object of the present invention is to provide a method for liquefying coal that can liquefy coal at a high conversion rate.

(Structure of the Invention) In order to achieve this object, the present invention provides a method for hydrocracking coal by adding hydrogen at high temperature and high pressure in the presence of a coal liquefaction catalyst. It is characterized by using low-grade iron ore that has been soaked in water for a long time.

(Detailed Description of the Invention) The present invention provides a catalyst for coal liquefaction made of low-grade iron ore which is prepared by subjecting low-grade iron ore to the treatment described below to sufficiently remove poisonous substances, and by applying this treatment to low-grade iron ore. In this method, hydrogen is added to coal in the presence of a solvent under high temperature and pressure to hydrocrack it and liquefy it.

The low-grade iron ore according to the present invention has a nickel content of 0.
Contains 3-3% by weight, iron content 10-50% by weight, chromium content 0.5-10%,
A material having a ratio of 3 or less and a specific surface area of 50 to 100 m279, such as laterite ore, is preferred. The reason why low-grade iron ore with such properties is used as a catalyst is as follows. Iron, nickel, and chromium act as catalysts to show activity in the hydrogenation reaction of aromatic compounds. In iron ore, as the nickel content increases, the iron content tends to decrease, and when the nickel content is 0.5 to 3% by weight, the iron content is 50 to 10% by weight. According to experiments conducted by the present inventors, it has been found that the above-mentioned hydrogenation reaction activation effect is significant when the amount is within this range. Regarding the chromium content, if it is less than 0.5% by weight, the above-mentioned effect cannot be obtained,
Further, even when the content exceeded 10% by weight, no particular improvement in the above-mentioned effects appeared. From this, it was found that a material containing nickel, iron, and chromium in the above-mentioned ranges is suitable.

In addition, At203,5IO2 has the effect of exhibiting catalytic activity as an acid, but when the At203/5iO2 ratio exceeds 3, the catalytic activity decreases, and alumina (At20
3) changes into a compound with metals and a spinel structure, and its activity decreases. From this, At203/510
It is preferable that the ratio of 2 to 3 is 3 or less.

The specific surface area is an important factor in physically increasing the activity of iron ore as a catalyst, and the specific surface area is 50 m”711
If it is less than that, the desired iron ore activity cannot be obtained. - As a result of experiments conducted by the present inventors, it was found that when the force specific surface area exceeds 100 m%, the catalytic activity decreases. Therefore, the specific surface area is 5
A range of 0 to 100 m4 is suitable.

In the present invention, the low-grade iron ore is not directly used as a catalyst, but is washed with water or immersed in water for a long time (for example, about 100 hours) and then dried. use. That is, iron ore contains poisonous substances such as alkali metal salts and alkaline earth metal salts.

For example, laterite ore contains MgO + CaO, Na2O
+ contains 3 to 10% by weight of 20 and the like. By the treatment of the present invention, when iron ore is washed with water or immersed in water for a long time, poisonous substances such as water-soluble alkali metal salts and alkaline earth metal salts are eluted and removed, and iron ore becomes a catalyst. Can increase activity. An example of removing alkali metal salts and the like by washing with water is shown in the table below. The numbers in this table indicate the amount contained in iron ore.

Further, when washed with water or immersed in water for a long time, the specific surface area increases, and from this, the catalytic activity of iron ore can be increased. For example, one with a specific surface area of 60 to 70 degrees before washing with water is 9
It can be improved to about 0frL''/jE.

It is preferable that the iron ore be washed with water or immersed for a long period of time, for example, until the pH of the iron ore washing or immersion solution reaches 7. This is because it is expected that when the pH is 7, the alkali metal salts and alkaline earth metal salts have been sufficiently removed.

The low-grade iron ore subjected to such treatment is added in an amount of 1 to 10 parts by weight per 100 parts by weight of coal.

This makes it possible to obtain the desired catalytic effect, and the amount added is smaller than the amount added in the conventional method using low-grade iron ore as a catalyst.

If necessary, sulfur or a sulfur compound is added as a cocatalyst. In the present invention, coal can be liquefied at a high conversion rate without using any sulfur, etc.;
It is also possible to further increase the conversion rate by adding 0.1 to 10 parts by weight.

In the present invention, these coals, low-grade iron ore catalysts, etc. are mixed together with a solvent. The type and amount of solvent added is the same as in the conventional coal liquefaction method using iron ore as a catalyst, such as sb, for example, 100 parts by weight of a solvent such as creosote oil per 100 parts by weight of coal.
It is preferable to add about 200 parts by weight.

Next, hydrogen is added to this mixture under high temperature and pressure,
Coal is hydrocracked and liquefied. Both the temperature and pressure conditions during hydrocracking can be lower than in conventional coal liquefaction methods. For example, in the conventional method, the temperature is 45
In the present invention, the temperature was 400°C and the initial hydrogen pressure was 1009/c, which was carried out under the conditions of 0°C and initial hydrogen pressure of 250ψ9.
It can be as low as r&.

(Effects of the Invention) According to the present invention, when using low-grade iron ore as a catalyst, it is washed with water or immersed in water for a long time and then dried before use, so that poisonous substances are removed. , increase the catalytic activity of iron ore. As a result, coal can be liquefied under conditions of low pressure and temperature, and at a high conversion rate, compared to conventional methods.

Coal can be liquefied without using a large amount of sulfur as a cocatalyst, and deterioration in quality can be prevented.

Example 1 Coal with a particle size of 60 mesh or less and properties shown in Table 1 was used, and low-grade iron ore with a particle size of 200 mesh or less was used.
The components and specific surface areas shown in Table 2 at 100% below were immersed in distilled water for 100 hours, washed with water, and then dried under reduced pressure.

This coal 50F, low grade iron ore 1.5F and sulfur 0.3
2 was thoroughly mixed with creosote oil 75F, and then charged into an I-no shaking autoclave. Then, the initial pressure of hydrogen is 1
After reaction treatment under the conditions of 00 kll/d, temperature of 400° C., and reaction time of 30 minutes, an extraction test and gas analysis of the contents were performed.

As a result, as shown in Table 3, tetrahydro 7 run (T
The conversion rate after HF) extraction was 79.7%.

Note that the conversion rate here indicates the proportion of gas and THF-soluble substances (for example, oil sphalaltenes; glare sphalaltenes) in the hydrocracked products of coal anhydrous and ashless pastes.

Table 3 Example 2 Coal was liquefied using the same coal and iron ore catalysts as in Example 1, without adding sulfur, and under the same conditions as in Example 1 except for the addition of sulfur. The results are shown in Figure 4.

Table 4 Comparative Examples The coal used in Example 1 was used, the iron ore used was one with the components and specific surface area shown in Table 2, and was washed with water, and the other conditions were the same as in Example 1. The liquefaction treatment was carried out. The results are shown in Table 5.

Table 5 Applicant's agent Patent attorney Takehiko Suzue Procedural amendment □, Tei 9. Ij,, 12.3 Manabu Shiga, Commissioner of the Patent Office1, Indication of the case, Japanese Patent Application No. 59-2042372, Name of the invention, Coal liquefaction method 3, Person making the amendment, Relationship with the case, Patent applicant (412) Nippon Kokan Co., Ltd. 4, Agent 5, Voluntary amendment 7, Contents of amendment (1) In the 20th line of page 1 of the specification, the word "water" is corrected to "hydrogen."

Claims (1)

[Claims] In a method of hydrocracking coal by adding hydrogen to coal in a solvent at high temperature and high pressure in the presence of a coal liquefaction catalyst, the above liquefaction catalyst may be washed with water or immersed in water for a long period of time and then dried. A method for liquefying coal, characterized by using low-grade iron ore.