JP6920952B2 - Catalysts for producing hydrocarbons from syngas, methods for producing catalysts, and methods for producing hydrocarbons from syngas - Google Patents

Description

The present invention relates to a catalyst for producing a hydrocarbon from a so-called synthetic gas containing carbon monoxide and hydrogen as main components, a method for producing the same, and a method for producing a hydrocarbon using the catalyst.

In recent years, environmental problems such as global warming have become apparent, H / C is higher than other hydrocarbon fuels, coal, etc., carbon dioxide emissions, which are the causative substances of global warming, can be suppressed, and reserves are available. The importance of abundant natural gas has been reassessed, and its demand is expected to increase in the future. Under such circumstances, infrastructure such as pipelines and LNG plants was found in remote areas in Southeast Asia and Oceania, but the recoverable reserves required huge investment. There are many small and medium-sized gas fields that are left undeveloped, and it is hoped that their development will be promoted. As one of the effective development means, after converting natural gas into synthetic gas, a lamp with excellent transportability and handleability is used by using the Fischer-Tropsch (FT, Fischer-Tropsch) synthesis reaction from the synthetic gas. The development of technology for converting to liquid hydrocarbon fuel such as light oil is being vigorously carried out in various places.

This FT synthesis reaction is an exothermic reaction that converts syngas into hydrocarbons using a catalyst, but it is extremely important to effectively remove the heat of reaction for stable operation of the plant. Reaction types that have been proven to date include a gas phase synthesis process (fixed bed, jet bed, fluid bed) and a liquid phase synthesis process in an organic solvent (slurry bed), each of which has its own characteristics. However, in recent years, the slurry bed-liquid phase synthesis process, which has high heat removal efficiency and does not cause accumulation of the generated high boiling point hydrocarbon on the catalyst and the accompanying blockage of the reaction tube, has attracted attention and has been energetically developed. I'm here.

In general, it goes without saying that the higher the activity of the catalyst, the more preferable it is, but especially in the slurry bed, there is a limitation that the slurry concentration must be kept below a certain value in order to maintain a good slurry flow state. Due to its presence, high catalyst activation is a very important factor in expanding the degree of freedom in process design.

The activity of various FT synthesis catalysts reported to date is at most 1 (hydrocarbon productivity) in the productivity of liquid hydrocarbons having 5 or more carbon atoms, which is a general index of productivity (hydrocarbon productivity). It is about kg-hydrocarbon / kg-catalyst / hour), which is not always sufficient from the above viewpoint (see Non-Patent Document 1). Here, the productivity of the liquid hydrocarbon is the production rate of the liquid product per unit mass of the catalyst, and is used as an index for evaluating the activity of the catalyst.

It has been reported that reducing the sodium content in silica used as a carrier is effective as one of the methods for improving the activity of the catalyst (see Non-Patent Document 2), but the sodium content is 0.01. Only the ones with less than mass% and the ones with about 0.3% by mass were compared, and there was no specific description as to how much the sodium content was reduced to achieve the effect.

In addition, as a result of detailed examination of the effects of impurities such as alkali metals and alkaline earth metals on the activity of the catalyst, by setting the impurity concentration to a catalyst within a certain range, the activity is greatly improved compared to conventional catalysts. (See Patent Document 1).

Further, in general, the smaller the particle size of the FT synthesis reaction catalyst is, the more preferable it is from the viewpoint of reducing the possibility that heat or diffusion of a substance becomes rate-determining. However, in the FT synthesis reaction using a slurry bed, high-boiling hydrocarbons among the produced hydrocarbons are accumulated in the reaction vessel, so that a solid-liquid separation operation between the catalyst and the product is absolutely necessary. If the particle size of the catalyst is too small, there arises a problem that the efficiency of the separation operation is greatly reduced. Therefore, the catalyst for the FT synthesis reaction in the slurry bed has an optimum particle size range, and it is generally said that the particle size is preferably about 20 to 250 μm and the average particle size is about 40 to 150 μm. However, as shown below, care must be taken as the catalyst may be destroyed or pulverized during the reaction, resulting in a smaller particle size.

That is, in the FT synthesis reaction on the slurry bed, the catalyst particles are often operated at a considerably high raw material gas superficial velocity (0.1 m / sec or more), and the catalyst particles collide violently during the reaction. If the strength and abrasion resistance (powder resistance) are insufficient, the catalyst particle size may decrease during the reaction, which may cause inconvenience in the separation operation. Further, in the FT synthesis reaction, a large amount of water is produced as a by-product, but when a catalyst having low water resistance and easily causes strength decrease, destruction, and pulverization by water is used, the catalyst particle size becomes fine during the reaction. This causes inconvenience in the separation operation as described above.

Further, in general, the catalyst for the FT synthesis reaction on the slurry bed is often pulverized so as to have the optimum particle size as described above, the particle size is adjusted, and the catalyst is put into practical use. However, such a crushed catalyst often has pre-cracks or sharp protrusions, and is inferior in mechanical strength and wear resistance. Therefore, when a crushed catalyst is used for the FT synthesis reaction on the slurry bed, the catalyst is destroyed and fine powder is generated, and it is extremely difficult to separate the generated high boiling point hydrocarbon from the catalyst. It had the drawback of becoming. Further, it is widely known that a catalyst having relatively high activity can be obtained by using porous silica as a catalyst carrier for the FT synthesis reaction. However, when the particle size is adjusted by crushing, it is described above. For these reasons, not only the strength of the catalyst is lowered, but also silica has low water resistance and is often destroyed and pulverized by the presence of water, which has often been a problem especially in a slurry bed.

In a reaction atmosphere in which a large amount of water by-produced by the FT reaction is present (particularly in an atmosphere with a high CO conversion rate), cobalt silicate is formed mainly at the interface between the supported cobalt, which is an active metal, and the silica carrier. This has been a problem because the catalyst activity may decrease due to the fact that the supported cobalt itself is oxidized or syntaring occurs. In addition, this phenomenon leads to the promotion of the deterioration rate of the catalyst over time, that is, the reduction of the catalyst life, which has been a factor of increasing the operating cost. These series of problems can be described as "low water resistance" of the active cobalt particles.
The above-mentioned decrease in catalytic activity is remarkable because the deterioration rate of the catalyst increases as the partial pressure of the by-product water increases, particularly in an atmosphere where the CO conversion rate is high. However, even in an atmosphere where the CO conversion rate is not high, such as 40 to 60%, the catalyst deteriorates at a relatively small rate according to the partial pressure of the by-product water, and the catalytic activity decreases. Therefore, from the viewpoint of catalyst life, it is important to improve the water resistance even under the condition that the CO conversion rate is relatively low.
It is said that the addition of zirconium is effective for suppressing the formation of cobalt silicate and improving the activity as described above, but in order to exert the effect, a large amount of zirconium, which is about half the mass of cobalt, is required. However, the effect was not sufficient even when a large amount of zirconium was added (see Patent Document 2).

In addition to the above, carbon precipitation on the surface of cobalt or at the interface between the supported cobalt and the silica carrier can be mentioned as a factor for reducing the catalytic activity. By covering the cobalt surface with the carbon component, the surface area of cobalt that can come into contact with the raw material gas is reduced, and the catalytic activity is reduced. In addition, poisoning by sulfur components, nitrogen components, etc. in the raw material gas and sintering in which cobalt metal aggregates during the reaction are generally known as factors for reducing catalytic activity.

Japanese Unexamined Patent Publication No. 2004-322805 U.S. Pat. No. 6,740,621

R. Oukaci et al., Applied Catalysis A: Genaral, 186 (1999) 129-144 J. Chen, Cuihua Xuebao, Vol.21, 2000, P169-171

According to the present invention, when hydrocarbons are produced from syngas using a catalyst, the activity of the catalyst is considered to be caused by the generation of sintering and carbon precipitation at the interface between the supported cobalt and the silica carrier, and the generation of by-product water. The purpose is to suppress the decrease. That is, the subject of the present invention is to obtain hydrocarbons from synthetic gas, which can be stably used under conditions where a large amount of by-product water is generated, particularly under conditions of high CO conversion rate, and has a long catalyst life. It provides a catalyst to be produced, a method for producing the catalyst, and a method for producing a hydrocarbon using the catalyst.

When producing a hydrocarbon from a synthetic gas using the FT synthesis reaction, the present inventors use a carrier containing silica as a main component, which is a cobalt metal and a titanium oxide, or a cobalt metal and a cobalt oxide, and a titanium. When a catalyst having a small amount of impurities supporting an oxide is used, a catalyst having a small amount of impurities, which supports a cobalt metal or a cobalt metal and a cobalt oxide, but does not support a titanium oxide, is used as compared with the case where a catalyst having a small amount of impurities is used. The water resistance of the catalyst is significantly improved under the condition where a large amount of by-product water is generated, especially under the condition of high CO conversion rate, the catalyst can be stabilized, and the catalyst life is also maintained under the condition of relatively low CO conversion rate. We found that the number of catalysts increased, and came to the present invention.
The impurities in the catalyst referred to in the present invention also include impurities in the catalyst carrier containing silica as a main component. More details are as described below.

(1) A catalyst for producing hydrocarbons from syngas, in which a catalyst carrier containing silica as a main component is supported with a cobalt metal and a titanium oxide, or a cobalt metal, a cobalt oxide and a titanium oxide. , The total content of each of sodium, potassium, calcium, and magnesium in the catalyst as a metal equivalent or less is 0.070% by mass or less. The catalyst to be manufactured.
(2) The total content of each simple substance of sodium, potassium, calcium, and magnesium in the catalyst and each compound in terms of metal is 0.030% by mass or less (1). A catalyst for producing hydrocarbons from the syngas described.
(3) The carrying ratio of the cobalt metal in the catalyst, or the carrying ratio of the cobalt metal and the cobalt oxide in the catalyst is 5 to 50% by mass in terms of cobalt metal, and the carrying ratio of the titanium oxide in the catalyst. The molar ratio (Ti / Co) of the amount to the supported amount of the cobalt metal in the catalyst or the supported amount of the cobalt metal and the cobalt oxide in the catalyst is 0.03 to 0.6. A catalyst for producing a hydrocarbon from the synthetic gas according to (1) or (2).
(4) A catalyst for producing a hydrocarbon from the synthetic gas according to any one of (1) to (3), wherein the catalyst carrier is spherical.

(5) A method for producing a catalyst for producing a hydrocarbon from a synthetic gas according to any one of (1) to (4), wherein a catalyst carrier containing silica as a main component is used as a cobalt precursor and a titanium precursor. Using the body, a cobalt compound and a titanium compound are supported separately by an impregnation method, and after each of the compounds is supported, a drying treatment, a drying treatment and a baking treatment, or a drying treatment, a baking treatment and a reduction treatment are performed. A method for producing a catalyst for producing a hydrocarbon from a synthetic gas, which is characterized by producing the catalyst.
(6) The invention according to (5), wherein when the cobalt compound and the titanium compound are supported by using the impregnation method, the titanium compound is first supported and then the cobalt compound is supported. A method for producing a catalyst for producing a hydrocarbon from syngas.
(7) The method for producing a catalyst for producing a hydrocarbon from the synthetic gas according to (5) or (6), wherein the cobalt precursor used in the impregnation method is cobalt acetate.
(8) The total content of each simple substance of sodium, potassium, calcium, and magnesium contained in the catalyst carrier and each compound in terms of metal is 0.080% by mass or less. (5) A method for producing a catalyst for producing a hydrocarbon from the synthetic gas according to any one of (7).
(9) The item according to any one of (5) to (8), wherein the content of the simple substance of sodium and the compound contained in the catalyst carrier in terms of metal is 0.030% by mass or less. A method for producing a catalyst for producing a hydrocarbon from the synthetic gas of.
(10) When producing the catalyst carrier containing silica as a main component, a silica sol produced by mixing an alkaline silicate aqueous solution and an acid aqueous solution is gelled, and after at least one of acid treatment and water washing treatment is performed, the silica sol is subjected to at least one of acid treatment and water washing treatment. The method for producing a catalyst for producing a hydrocarbon from a synthetic gas according to any one of (5) to (9), which is produced by firing.
(11) In at least one of the acid treatment and the washing treatment after gelation of the silica sol, the total content of each simple substance of sodium, potassium, calcium and magnesium and each compound in terms of metal is 0.06 mass. The method for producing a catalyst for producing a hydrocarbon from the synthetic gas according to (10), which comprises using water having a percentage of% or less.
(12) The gelation of the catalyst for producing a hydrocarbon from the synthetic gas according to (10) or (11) is characterized in that the silica sol is sprayed into a gas medium to form a spherical shape. Production method.
(13) The catalyst carrier containing silica as a main component is washed with at least one of ion-exchanged water, acid and alkali to reduce the concentrations of sodium, potassium, calcium and magnesium, and then the cobalt compound. The method for producing a catalyst for producing magnesium from the synthetic gas according to any one of (5) to (12), which comprises supporting the titanium compound.

(14) Hydrocarbons from syngas, which are characterized by producing hydrocarbons from syngas by a liquid phase reaction on a slurry bed using the catalyst according to any one of (1) to (4). How to manufacture.

According to the present invention, a catalyst having high stability and a long life even under conditions where a large amount of by-product water is generated, especially under a high CO conversion rate condition, and a method for producing the catalyst and a synthetic gas using the catalyst are used for hydrocarbonization. A method for producing hydrogen can be provided.

Hereinafter, an embodiment of a catalyst for producing a hydrocarbon from a synthetic gas of the present invention, a method for producing the catalyst, and a method for producing a hydrocarbon from a synthetic gas will be described in more detail. First, a catalyst for producing a hydrocarbon from the synthetic gas according to the present embodiment will be described.

The catalyst in the present embodiment is a cobalt-based catalyst having activity in the FT synthesis reaction, and serves as a catalyst carrier containing silica as a main component (hereinafter, also simply referred to as a carrier), a cobalt metal as an active catalyst, and a co-catalyst. It has a titanium oxide. The cobalt component, which is an active catalyst, mainly exists as a metal carrier (cobalt metal), but a part of it may exist as an oxide (cobalt oxide). That is, the catalyst in the present embodiment is formed by supporting a cobalt metal and a titanium oxide or a cobalt metal, a cobalt oxide and a titanium oxide on a catalyst carrier containing silica as a main component.

Cobalt metal is mainly responsible for the activity for the FT synthesis reaction. As described below, the cobalt metal and cobalt oxide are once supported on the carrier in a mixed state, but after being reduced in a hydrogen stream at a high temperature of about 500 ° C. to obtain most of the cobalt metal. It is subjected to the FT synthesis reaction.

As a carrier that supports a cobalt metal or a cobalt oxide, a carrier containing silica as a main component is selected and used. The carrier containing silica as a main component may contain a composite oxide such as alumina or magnesia in addition to silica. The mass ratio of silica in the carrier containing silica as a main component is 50% or more.
The carrier of the present embodiment includes a carrier containing a small amount of impurities unavoidably mixed in the manufacturing process of the silica carrier as a component other than silica, or a composite oxidation with alumina or zeolite when an acid point is desired to be introduced. It also includes the carrier, which has been made into a product. (Hereinafter, a carrier containing silica as a main component is also simply referred to as a "silica carrier").

Further, as will be described in detail later, the impurities in the silica carrier of the present embodiment refer to simple substances and compounds of sodium, potassium, calcium and magnesium, and limit the content of these impurities. These impurities are unavoidably contained in the starting material of the silica carrier or the washing water used in the manufacturing process of the silica carrier, or by being directly mixed from the reaction apparatus used in the manufacturing process. Impurities that can be contained in the silica and affect the catalytic capacity. Further, in the manufacturing process in which the cobalt metal and the titanium oxide, or the cobalt metal, the cobalt oxide and the titanium oxide are supported on the silica carrier, they can be inevitably mixed in the same manner as described above.

Impurities that can generally be unavoidably contained in each of the above-mentioned manufacturing steps include iron and aluminum in addition to sodium, potassium, calcium and magnesium. However, most of the impurity element aluminum is aluminum oxide contained in silica sand, which is the starting material of the silica carrier, and exists in the form of alumina or zeolite in the silica carrier, so that it does not affect the catalytic ability in the present invention. .. It is known that iron itself has FT reaction activity, and the amount of iron mixed in each manufacturing process as described above has almost no effect on FT reaction activity.
From the above, in the present embodiment, the content of each simple substance of sodium, potassium, calcium, magnesium and each compound is reduced. Hereinafter, in the present embodiment, when simply described as an impurity, it refers to sodium, potassium, calcium, and magnesium.

Impurities such as sodium, potassium, calcium and magnesium are mainly present in the form of compounds, particularly in the form of oxides, but may also be present in small amounts in the form of elemental metals or non-oxides. In order to exhibit good catalytic activity, longevity and high water resistance, the total amount of impurities in the catalyst is 0.070% by mass or less in terms of metal (however, the total mass of the catalyst including the silica carrier is 100%. (Mass not converted to metal)) must be suppressed. If it exceeds this amount, the activity is greatly reduced, which is a significant disadvantage. Particularly preferably, the total amount of impurities in the catalyst is 0.030% by mass or less in terms of metal. However, reducing the amount of impurities more than necessary is costly and uneconomical in improving purity, so the total amount of impurities in the catalyst is preferably 0.01% by mass or more in terms of metal.

As a method for measuring the impurity concentration, a method of ICP emission spectroscopic analysis may be used after dissolving the carrier and the catalyst with hydrofluoric acid. In order to measure the impurity concentration in the entire catalyst, the entire catalyst may be dissolved with hydrofluoric acid, and then each impurity component may be analyzed by ICP emission spectroscopic analysis. Moreover, since the catalyst manufacturing process has multiple stages, it is preferable to analyze impurities at each stage. For example, by first performing an impurity analysis only on the carrier to be used, then performing an impurity analysis at the stage where the titanium oxide is supported, and then performing an impurity analysis at the stage where the cobalt metal is supported, the amount of impurities only on the carrier can be determined. It is possible to estimate the amount of increase in impurities due to supporting titanium oxide on the carrier, the amount of increase in impurities due to supporting cobalt metal, and the like.
In the analysis method, the concentration in terms of metal is obtained regardless of whether sodium, potassium, calcium, or magnesium is in an oxide state or in a metal state. Therefore, in the present invention, the impurity concentration is defined by a metal conversion value.

The catalyst in the present embodiment is a catalyst containing a carrier containing silica as a main component and carrying a cobalt metal and a titanium oxide, or a cobalt metal and a cobalt oxide and a titanium oxide, and has a small amount of impurities. As described above, by reducing impurities and using titanium oxide as a co-catalyst, the improvement of water resistance, which is a problem of the catalyst for FT synthesis, is remarkably improved as compared with the catalyst without titanium oxide. Can be used as a catalyst.
The effects of improving water resistance are as follows: (1) The presence of titanium oxide on the silica carrier reduces the interface between the active cobalt particles and the silica carrier, thereby accelerating the formation of cobalt silicate by by-product water. The formation is suppressed, and (2) the interaction between the titanium oxide and the active cobalt particles is larger than the interaction between the silica carrier and the active cobalt particles. It is presumed that syntaring is relatively unlikely to occur between the cobalt particles exhibiting the activity of the above, and it is considered that the water resistance is improved even in an atmosphere in which by-product water in which syntaring is likely to occur is present. It is considered that the effect of extending the life of the catalyst is due to the fact that the catalyst structure exhibiting the activity can be maintained for a longer period of time by the above-mentioned improvement of water resistance and suppression of sintering.

With a catalyst containing a large amount of impurities, the amount of titanium added required to sufficiently exhibit the effects of improving water resistance and extending the catalyst life was extremely large, which was uneconomical or the effects could not be sufficiently obtained. It has been found that the catalyst of the present embodiment has a sufficient and high effect even if a small amount of titanium is added. It is presumed that this is because the complex compound of the silica carrier and titanium is easily formed homogeneously due to the small amount of impurities in the catalyst, and the characteristics of the surface of the silica carrier can be efficiently changed even with a small amount of titanium.

The appropriate range of the cobalt carrying rate is at least the minimum amount for developing the activity, and at least the supporting amount at which the dispersity of the carried cobalt is extremely lowered and the proportion of cobalt that cannot contribute to the reaction increases. All you need is. Specifically, it is preferably 5 to 50% by mass in terms of cobalt metal (however, the mass of the entire catalyst including the silica carrier is 100% (mass not converted to metal)), and more preferably 10 to 40% by mass. .. If it is less than this range, the activity cannot be sufficiently expressed, and if it exceeds this range, the dispersity is lowered and the utilization efficiency of the carried cobalt is lowered, which is uneconomical, which is not preferable. The cobalt support rate referred to here refers to the ratio of the mass of metallic cobalt to the total catalyst mass when it is considered that the supported cobalt is 100% reduced because it is not always 100% reduced. .. The carrying ratio of cobalt can be analyzed by using the method of ICP emission analysis as well as impurities.

The appropriate range of the amount of titanium supported together with cobalt is at least the minimum amount for exhibiting the effect of improving water resistance, the effect of extending the life of the catalyst, the effect of improving activity, and the effect of promoting regeneration, and the degree of dispersion of the carried titanium is extremely high. The proportion of titanium added that does not contribute to the manifestation of the effect becomes high, and the amount of titanium added may be less than or equal to the amount supported, which is uneconomical. Specifically, it is preferable to adjust the carrying amount of titanium so that the molar ratio of the carrying amount of the cobalt metal and the cobalt oxide to the carrying amount of titanium is Ti / Co = 0.03 to 0.6. More preferably, Ti / Co = 0.05 to 0.3. If it is less than this range, the effect of improving water resistance and the effect of extending the life cannot be sufficiently exhibited, and if it exceeds this range, the utilization efficiency of the carried titanium is lowered and it becomes uneconomical, which is not preferable. The amount of titanium supported can also be analyzed by using the method of ICP emission analysis.

As described above, in the present embodiment, it is important to reduce the content of impurities in the catalyst. According to the present inventors, it was found that the impurities in the catalyst composed of sodium, potassium, magnesium and calcium are mainly derived from the washing water used in the manufacturing process of the silica carrier and the starting material of the carrier. From this, the total content of each simple substance of sodium, potassium, magnesium, and calcium in the carrier and each compound is 0.080% by mass or less in terms of metal (however, the mass of the silica carrier is 100%). ), More preferably 0.06% by mass or less in terms of metal, further preferably 0.04% by mass or less in terms of metal, and particularly preferably 0.030% by mass or less in terms of metal. However, similarly here, it is uneconomical to reduce the content of sodium, potassium, magnesium, and calcium in the carrier more than necessary, so even if the content is contained within a range that does not adversely affect the catalytic activity. I do not care. If the total content of sodium, potassium, magnesium, and calcium in the carrier is reduced to about 0.01% by mass in terms of metal, a sufficient effect can be obtained. Therefore, sodium, potassium, magnesium, and calcium in the carrier can be obtained. It is preferable that the total content of calcium is 0.01% by mass or more in terms of metal from the viewpoint of cost.

It was also found that sodium has a more adverse effect on catalytic performance than potassium, magnesium and calcium. The content of sodium as a simple substance and a compound in the carrier is preferably 0.030% by mass or less in terms of metal, more preferably 0.02% by mass or less in terms of metal, and even more preferably 0.% by mass in terms of metal. It is 01% by mass or less. Here as well, since it is uneconomical to reduce the sodium content in the carrier more than necessary, the sodium content may be contained within a range that does not adversely affect the catalytic activity. The content of sodium in the carrier is preferably 0.002% by mass or more in terms of metal, from the viewpoint of cost.

The catalyst used in the FT synthesis reaction method is required to have the above-mentioned physical strength and abrasion resistance (powder resistance). In general, the catalyst for the FT synthesis reaction on the slurry bed is often pulverized to have the optimum particle size as described above, the particle size is adjusted, and the catalyst is put into practical use. However, such crushed catalysts often have pre-cracks or sharp protrusions, and are inferior in mechanical strength and wear resistance. Therefore, they are not crushed carriers but spherical. A catalyst using a carrier is preferable.

Next, the method for producing the catalyst of the present embodiment will be described.
In the method for producing a catalyst of the present embodiment, a cobalt precursor and a titanium precursor are used on a catalyst carrier containing silica as a main component, and a cobalt compound and a titanium compound are supported separately or simultaneously by an impregnation method. After each compound is supported, it is produced by performing a drying treatment, a drying treatment and a baking treatment, or a drying treatment, a baking treatment and a reduction treatment.

The method of supporting cobalt metal and titanium oxide, or cobalt metal and cobalt oxide and titanium oxide is the usual impregnation method or one of them, the Incipient Wetness method, or the precipitation method or ion exchange method. Etc. As a cobalt compound or a titanium compound which is a raw material (precursor) used in the support, a counter ion (for example, Co (CH ₃ COO) _{2 in the case of acetate) is used during the reduction treatment, the calcination treatment and the reduction treatment after the support.} The inside (CH ₃ COO)) volatilizes and decomposes, and there is no particular limitation as long as it dissolves in a solvent. For example, acetates, nitrates, carbonates, chlorides, organic compounds, etc. can be used, but it is safer to use a water-soluble compound that can use an aqueous solution when carrying out the carrying operation. It is preferable for securing a manufacturing work environment. Specifically, cobalt acetate, cobalt nitrate, cobalt chloride, titanium chloride and the like are preferable because they are easily changed to cobalt oxide or titanium oxide at the time of firing, and the subsequent reduction treatment of cobalt oxide is also easy. Of these, cobalt acetate is more preferable as a precursor because it can be supported on a carrier containing silica as a main component in a highly dispersed manner and has high stability. The reason for the high stability is that the interaction between the cobalt particles formed by the production of the catalyst and the carrier becomes strong, and the decrease in activity such as sintering, which is considered to be promoted by the contact with the by-product water, is suppressed. It is presumed to be due.

The support of the cobalt compound and the titanium compound on the carrier containing silica as the main component can be performed by the above-mentioned supporting method, and the timing of supporting the cobalt compound and the titanium compound can be performed separately or simultaneously. , It is preferable to support them separately.

When a cobalt compound and a titanium compound are supported at the same time, a mixed solution of the cobalt compound and the titanium compound is prepared and supported. After the support, a drying treatment (for example, 100 ° C-1h in air) is performed as necessary, followed by a reduction treatment (for example, 450 ° C-15h in normal pressure hydrogen flow) or a firing treatment (for example, 450 ° C-15h in air). ) And reduction treatment. By performing such a treatment, all of the cobalt compound is metallized, or a part of the cobalt compound is metallized and the rest is oxidized, and the titanium compound is oxidized. However, it has been clarified that when the cobalt compound and the titanium compound are supported at the same time, the water resistance may be lowered as compared with the catalyst which does not support the titanium compound. This is because in a catalyst that simultaneously supports a cobalt compound and a titanium compound, the active cobalt particles and titanium oxide take an unstable form in which the surface area of the active cobalt particles decreases due to contact with by-product water. It is presumed that this is the case.

When supporting the cobalt compound and the titanium compound separately, a solution of the cobalt compound and a solution of the titanium compound are prepared respectively, and one of the solutions is first supported on a carrier containing silica as a main component and dried. , Subsequent reduction treatment, or calcining treatment and reduction treatment are carried out, and then the other solution is further supported on the carrier. After the support, a drying treatment is performed as necessary, followed by a reduction treatment, a firing treatment, and a reduction treatment. By performing such a treatment, all of the cobalt compound is metallized, or a part of the cobalt compound is oxidized and the rest is metallized, and the titanium compound is oxidized.

In the above reduction treatment, some cobalt compounds may remain without being reduced to cobalt metal, but in order to exhibit good activity, the cobalt compound reduced to cobalt metal is not reduced to cobalt. More than a compound is preferable. This can be confirmed by the chemisorption method.

The catalyst after the reduction treatment must be handled so that it will not be oxidatively deactivated by contact with the atmosphere. However, if the surface of the cobalt metal on the carrier is stabilized from the atmosphere, it will be handled in the atmosphere. It is possible and suitable. In this stabilization treatment, a so-called passivation (passivation treatment) is performed in which nitrogen, carbon dioxide, or an inert gas containing a low concentration of oxygen is brought into contact with the catalyst to oxidize only the polar surface layer of the cobalt metal on the carrier. When the FT synthesis reaction is carried out in a liquid phase, there is a method of immersing it in a reaction solvent or molten FT wax to block it from the atmosphere. good.

Further, as a result of diligent studies by the present inventors, when the cobalt compound and the titanium compound are separately supported, it is preferable to sequentially support the titanium compound and the cobalt compound in this order. On the contrary, it was clarified that the catalyst in which the cobalt compound and the titanium compound were supported in this order had a lower life extension effect and a water resistance improvement effect as compared with the former. It is presumed that the catalyst structure in which the titanium oxide is present on the silica carrier and the cobalt particles exhibiting activity are present on the titanium oxide is preferable.

As a specific preparation method, the drying treatment is carried out even if a drying treatment (for example, 100 ° C.-1h in air) is carried out after the support of the cobalt compound and then a firing treatment (for example, 450 ° C.-5h in air) is carried out. The cobalt impregnation carrier, which is the next step, may be carried out only by itself. In order to prevent the addition efficiency of titanium from being lowered due to the titanium compound being incorporated into the cobalt compound during the cobalt impregnation loading operation, a firing treatment is performed after the drying treatment to convert it into a titanium oxide. It is good.
Then, after impregnating and supporting the cobalt compound, if necessary, a drying treatment is performed, and then the cobalt compound on the carrier surface is reduced to a cobalt metal (for example, 450 ° C.-15 h in a normal pressure hydrogen stream) to obtain a catalyst. can get. After the impregnation of the cobalt compound is supported, the reduction treatment may be carried out after calcination to change into an oxide, or the reduction treatment may be carried out directly without calcination.

As one of the methods for obtaining a catalyst having less impurities, the amount of impurities contained in a cobalt compound and a titanium oxide, for example, cobalt acetate, cobalt nitrate, cobalt chloride, titanium chloride, etc., which are raw materials (precursors) used in the above-mentioned carrier. It is effective to reduce. Specifically, it is effective to suppress the total content of each element of sodium, potassium, calcium, and magnesium in these raw materials (precursors) to 5% by mass or less in terms of metal.

Another method of effectively reducing impurities in the catalyst is to prevent impurities from entering in the manufacturing process of the silica-based carrier.

Generally, the method for producing a silica carrier is roughly classified into a dry method and a wet method. The dry method includes a combustion method, an arc method, and the like, and the wet method includes a precipitation method, a gel method, and the like, and it is possible to produce a catalyst carrier by any of the production methods. However, in the above methods other than the gel method, it is technically and economically difficult to form the catalyst carrier into a spherical shape. Therefore, the silica sol is sprayed in a gas medium or a liquid medium to easily form the gel into a spherical shape. The gel method is preferable.

The gel is formed by spraying a silica sol produced by mixing an aqueous acid aqueous solution of silicate and an aqueous acid solution in a gas medium or a liquid medium to form a spherical shape, and then at least one of acid treatment and water washing treatment. After that, it becomes a silica carrier by firing.

When producing a silica carrier by the above gel method, a large amount of washing water is usually used, but if washing water containing a large amount of impurities such as industrial water is used, a large amount of impurities will remain in the carrier. , The activity of the catalyst is significantly reduced, which is not preferable. However, by using a washing water having a low impurity content or containing no impurities such as ion-exchanged water, it is possible to obtain a good silica carrier having a low impurity content. In this case, the total content of impurities sodium, potassium, calcium, and magnesium in the washing water is preferably 0.06% by mass or less in terms of metal, and if it exceeds this, the impurity content in the silica carrier increases. This is not preferable because the amount of the catalyst increases and the activity of the catalyst after preparation is greatly reduced. Ideally, it is preferable to use ion-exchanged water, and in order to obtain ion-exchanged water, it may be manufactured using an ion-exchange resin or the like, but silica gel generated as a nonstandard product on the silica carrier production line is used. It can also be manufactured by performing ion exchange using it.

Abrasion resistance and strength are required for a catalyst for an FT synthesis reaction using a slurry bed (FT synthesis catalyst). Further, in the FT synthesis reaction, since a large amount of water is produced as a by-product, if a catalyst or carrier that is destroyed or pulverized in the presence of water is used, the above-mentioned inconvenience will occur. Be careful. Therefore, a catalyst using a spherical carrier is preferable to a crushed carrier that is likely to have pre-cracks and has sharp corners that are easily broken and peeled off. When producing a spherical carrier, it may be formed into a spherical shape by using a spraying method such as a general spray-drying method based on the gel method. In particular, when producing a spherical silica carrier having a particle size of about 20 to 250 μm, the spraying method is suitable, and a spherical silica carrier having excellent wear resistance, strength, and water resistance can be obtained.

A method for producing such a silica carrier is illustrated below.
A silica sol generated by mixing an aqueous alkali silicate solution and an aqueous acid solution under a condition of pH 2 to 10.5 is sprayed into a gas medium such as air or an organic solvent insoluble in the sol to gel. Then, acid treatment, washing with water, and drying. Here, as the alkali silicate, an aqueous solution of sodium silicate is preferable, _{the molar ratio of Na 2} O: SiO ₂ is 1: 1 to 1: 5, and the concentration of silica is preferably 5 to 30% by mass. As the acid to be used, nitric acid, hydrochloric acid, sulfuric acid, organic acid and the like can be used, but sulfuric acid is preferable from the viewpoint of preventing corrosion to the container during production and leaving no organic matter. The acid concentration is preferably 1 to 10 mol / L, and if it is below this range, the progress of gelation is remarkably slowed down, and if it exceeds this range, the gelation rate is too fast and its control becomes difficult, so that the desired physical property value is obtained. It is not preferable because it becomes difficult to obtain. Further, when a method of spraying into an organic solvent is adopted at the time of gelation, kerosene, paraffin, xylene, toluene or the like can be used as the organic solvent.

When the impurities in the silica carrier can be reduced by performing pretreatment such as washing with water, washing with acid, washing with alkali, etc. without significantly changing the physical and chemical properties of the catalyst carrier. , These pretreatments are extremely effective in improving the activity of the catalyst.

For example, for cleaning the silica carrier, it is particularly effective to clean it with an acidic aqueous solution such as nitric acid, hydrochloric acid, or acetic acid, or with ion-exchanged water. When it becomes an obstacle that a part of the acid remains in the carrier after the washing treatment with these acids, it is effective to further wash with clean water such as ion-exchanged water.

Further, in the production of the silica carrier, a firing treatment for the purpose of improving the particle strength and the surface silanol group activity is often performed. However, if firing is performed with a relatively large amount of impurities in the carrier, when the silica carrier is washed to reduce the impurity concentration, the impurity element is incorporated into the silica skeleton to reduce the impurity content. Becomes difficult. Therefore, when it is desired to wash the silica carrier to reduce the impurity concentration, it is preferable to use uncalcined silica gel.

The reason why silica captures impurities in the washing water is that hydrogen in silanol on the surface of silica exchanges ions with sodium, potassium, calcium, and magnesium ions. Therefore, even if the washing water contains a small amount of impurities, by adjusting the pH of the washing water to a low level, it is possible to prevent the trapping of impurities to some extent, and it is possible to suppress a decrease in the activity of the catalyst. In addition, since the amount of ion exchange (impurity contamination) is proportional to the amount of washing water used, reducing the amount of washing water, in other words, increasing the efficiency of water use until the end of washing with water, also increases the amount of impurities in the silica carrier. Can be reduced.

The impurity concentration in the carrier as a raw material in the manufacturing process can be evaluated by ICP emission analysis of the carrier before supporting the cobalt metal or the like. Further, by measuring the impurity concentration in the carrier before and after washing, the effect of reducing impurities in the carrier by washing the carrier can be evaluated.

In order to keep the dispersity of the metal high and improve the efficiency of contributing to the reaction of the supported active metal, it is preferable to use a carrier having a high specific surface area. However, in order to increase the specific surface area of the carrier, it is necessary to reduce the pore diameter and increase the pore volume, but if these two factors are increased, the wear resistance and strength will decrease. , Not preferable. As the physical properties of the carrier, a carrier having a pore diameter of 8 to 50 nm, a specific surface area of 80 to 550 m ² / g, and a pore volume of 0.2 to 1.5 mL / g at the same time is used as a carrier for a catalyst. Suitable. It is more preferable that the pore diameter is 8 to 30 nm, the specific surface area is 150 to 450 m ² / g, and the pore volume is 0.3 to 1.2 mL / g at the same time. It is more preferable if the amount is 200 to 400 m ² / g and the pore volume is 0.4 to 1.0 mL / g at the same time. The specific surface area can be measured by the BET method, and the pore volume can be measured by the mercury intrusion method or the water droplet determination method. The pore diameter can be measured by a gas adsorption method or a mercury intrusion method using a mercury porosimeter, but it can also be calculated from the specific surface area and the pore volume.

In order to obtain a catalyst exhibiting sufficient activity for the FT synthesis reaction, the specific surface area of the catalyst carrier ^{needs to be 80 m 2} / g or more. If it is less than this specific surface area, the dispersity of the supported metal is lowered, and the efficiency of contribution of the active metal to the reaction is lowered, which is not preferable. Further, when the specific surface area of the catalyst carrier is ^{more than 550 m 2} / g, it is difficult for the pore volume and the pore diameter to satisfy the above ranges at the same time, which is not preferable. Therefore, the specific surface area of the catalyst carrier ^{is preferably 80 to 550 m 2} / g.

The smaller the pore diameter of the catalyst carrier, the larger the specific surface area, but if it is less than 8 nm, the gas diffusion rate in the pores differs between hydrogen and carbon monoxide, and the deeper the pores, the more hydrogen. This is not preferable because a large amount of light hydrocarbons such as methane, which can be said to be a by-product, is produced in the FT synthesis reaction, which results in an increase in the partial pressure. In addition, the diffusion rate of the produced hydrocarbon in the pores is also reduced, and as a result, the apparent reaction rate is reduced, which is not preferable. Further, when comparison is performed with a constant pore volume, the specific surface area decreases as the pore diameter increases. Therefore, when the pore diameter exceeds 50 nm, it becomes difficult to increase the specific surface area and the dispersity of the active metal decreases. This is not preferable. Therefore, the pore size of the catalyst carrier is preferably 8 to 50 nm.

The pore volume of the catalyst carrier is preferably in the range of 0.2 to 1.5 mL / g. If the pore volume is less than 0.2 mL / g, it is difficult for the pore diameter and the specific surface area to satisfy the above ranges at the same time, which is not preferable, and if the pore volume is more than 1.5 mL / g, It is not preferable because the strength is extremely reduced.

By using the catalyst according to the present embodiment as described above, the FT synthesis reaction can be carried out with high efficiency and low cost, and hydrocarbons can be stably produced. That is, when the FT synthesis reaction is carried out by a liquid phase reaction using a slurry bed using the catalyst obtained in the present embodiment, the selectivity of the main product, a liquid product having 5 or more carbon atoms, is high. In addition, the production rate (hydrocarbon productivity) of the liquid product per unit mass of the catalyst is also extremely high. Further, the catalyst of the present embodiment has a feature that the catalyst life is long because the degree of catalyst pulverization during use (during the synthesis reaction) and the decrease in activity due to by-product water and the like are very small. These features make it possible to carry out the FT synthesis reaction with high efficiency and low cost.

Further, if a hydrocarbon is produced from a synthetic gas using the catalyst according to the present embodiment, the decrease in activity due to by-product water or the like is very small, and high catalytic activity can be exhibited for a long period of time. A good FT synthesis reaction can be stably carried out under the condition that the partial pressure of water becomes very high, particularly under the condition that the one-pass CO conversion rate is 60 to 95%. The one-pass CO conversion rate referred to here is different from the one in which the gas containing the unreacted raw material gas discharged from the reactor is supplied to the reactor again, and the CO conversion rate is determined by passing the raw material gas through the reactor only once. It is what I asked for. Even when the one-pass CO conversion rate is relatively low at 40 to 60%, the decrease in activity due to by-product water or the like is very small, so that the catalyst life is extended and the catalyst cost can be reduced. When the one-pass CO conversion rate is 40% or less, the equipment cost of the tail gas recycling facility increases, so it is common to operate at 40% or more.

As the synthetic gas used for the FT synthesis reaction in the hydrocarbon production method of the present embodiment, a gas in which the total amount of hydrogen and carbon monoxide is 50% by volume or more of the total is preferable from the viewpoint of productivity. In particular, it is desirable that the molar ratio of hydrogen to carbon monoxide (hydrogen / carbon monoxide) is in the range of 0.5 to 4.0. This is because when the molar ratio of hydrogen to carbon monoxide is less than 0.5, the abundance of hydrogen in the raw material gas is too small, so that the hydrocarbonation reaction of carbon monoxide (FT synthesis reaction) does not proceed easily. This is because the productivity of liquid hydrocarbons does not increase. On the other hand, when the molar ratio of hydrogen to carbon monoxide exceeds 4.0, the abundance of carbon monoxide in the raw material gas is too small, and the catalytic activity. This is because the productivity of liquid hydrocarbons does not increase regardless.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these Examples.

The catalysts according to Examples 1 to 13 and Comparative Examples 1 to 5 were produced by the following methods.
The silica carrier supporting Ti and Co (Comparative Examples 1 to 3 carry only Co) is manufactured by Fuji Silysia Chemical Ltd.
Specifically, first, a silica sol produced by mixing an aqueous alkali silicate solution and an aqueous acid solution is prepared, and then sprayed in a gas to obtain a spherical dry sol having an average particle size of 100 μm, washed with water, and then calcined. By doing so, it becomes a silica carrier. However, in Comparative Examples 4, other Comparative Examples other than Comparative Example 5, and Examples, the total content of sodium, potassium, calcium, and magnesium during the water washing treatment before firing was 0.06 mass in terms of metal. A lot of silica carriers washed with water using ion-exchanged water of% or less was obtained. In Comparative Example 4 and Comparative Example 5, the water washing treatment was carried out using water having a total content of sodium, potassium, calcium and magnesium of 0.08% by mass and 0.09% by mass in terms of metal, respectively.

After dissolving the carrier using hydrofluoric acid before supporting a cobalt metal or the like, the contents of impurities Na, K, Ca, and Mg were analyzed using the technique of ICP emission spectroscopic analysis (Table). Described as the concentration of each element in the carrier inside).

As the metal solution for support, cobalt nitrate and titanium chloride were dissolved in ion-exchanged water to prepare an aqueous solution of cobalt nitrate and an aqueous solution of titanium chloride. In Example 13, it was prepared using cobalt acetate instead of cobalt nitrate. In Example 4, a metal solution of cobalt nitrate and titanium chloride was prepared using water having a total content of sodium, potassium, calcium, and magnesium of 0.1% by mass in terms of metal, instead of ion-exchanged water. ..

The silica carrier was washed with ion-exchanged water as a pretreatment for supporting, except for Examples 2 and 3. In Example 2, after washing with a 3% aqueous nitric acid solution, further washing with ion-exchanged water was performed. Further, in Example 3, after washing with a 3% potassium hydroxide aqueous solution, further washing with ion-exchanged water was performed.
After washing, Ti was first supported by an impregnation method, and a drying treatment (100 ° C-1h in air) and a firing treatment (450 ° C-5h in air) were performed. Next, Co is further supported by the impregnation method, and drying treatment (100 ° C-1h in air), firing treatment (450 ° C-5h in air), reduction treatment (450 ° C-15h in normal pressure hydrogen stream), and passivation. To prepare a catalyst. The Co carrying ratio is 20 to 30% by mass, and Ti / Co = 0 to 0.6.

The content of the metal component in the obtained catalyst is evaluated by dissolving the catalyst with hydrofluoric acid and then using the method of ICP emission spectroscopic analysis to obtain Co, Ti, Na, K, Ca and Mg. It was performed by analyzing the content of (listed as the concentration of each element in the catalyst in the table).

The catalytic activity was evaluated as follows.
Using an autoclave with an internal volume of 300 mL, 1 g of the above catalyst and 50 mL of n-C ₁₆ (n-hexadecane) were charged, and then the stirrer was rotated ^{at 800 min -1 under the conditions of 230 ° C. and 2.0 MPa-G.} _{Adjust F (synthetic gas (H 2} / CO = 2 (molar ratio)) flow rate) so that W (catalyst mass) / F (synthetic gas flow rate) = 1.5 (g · h / mol). Then, the synthetic gas was circulated. Then, during the synthesis reaction, the compositions of the supply gas and the autoclave outlet gas were determined by gas chromatography, and the CO conversion rate, CH ₄ selectivity, CO ₂ selectivity, and hydrocarbon with 5 or more carbon atoms were determined by the following formula (1). The catalytic activity was evaluated by obtaining the productivity (hydrocarbon productivity) of.

In addition, the following experiments were carried out to evaluate the water resistance of the catalyst.
After charging 2 g of the above catalyst and 50 mL of n-C ₁₆ (n-hexadecane), the conditions of 2.0 MPa-G, W (catalyst mass) / F (synthetic gas flow rate) = 3 (g · h / mol). Syngas (H ₂ / CO = 2 (molar ratio)) is circulated underneath, and the reaction temperature is adjusted so that the CO conversion rate is about 70% while rotating the ^{stirrer at 800 min -1, and F.} -T synthesis reaction was carried out.
When 20 hours had passed from the start of the reaction, stirring was stopped and held for ¹ hour, and then the stirrer was held again for 7 hours while rotating at 800 min -1. After that, stirring was stopped and held for 1 h, stirring was restarted and held for 7 hours was repeated, and these operations were performed 6 times during the test. ^{After resuming stirring at 800 min -1} from the 6th stirring stopped state, the reaction was stopped by holding for 7 hours in the same manner. During the reaction, the compositions of the supply gas and the autoclave outlet gas were determined by gas chromatography to obtain the CO conversion rate.

While the stirring is stopped, the inside of the reactor is not in a mixed state, and the catalyst particles settle to the bottom. The FT synthesis reaction proceeds on the cobalt metal, which is the active metal of the catalyst, and water is by-produced together with the hydrocarbon. Since the by-produced water is immediately mixed with the reducing raw material gas in the agitated state, the local moisture pressure in the vicinity of the active metal is not high, but the water stays in the vicinity of the active metal while the agitation is stopped. Therefore, the local water pressure becomes high. Under such circumstances, cobalt metal, which is an active metal, easily undergoes oxidation, aggregation, and coalescence.
The CO conversion rate before and after repeating the stirring stop operation 6 times, that is, the CO conversion rate when stirring is stopped 20 hours after the start of the reaction (CO conversion rate at 20 hours), and each operation of stirring and stopping is repeated 6 times. Water produced as a by-product by comparing with the CO conversion rate (CO conversion rate after repeating stirring stop 6 times) and the degree of change in CO conversion rate (variation in catalytic activity) with the passage of time. It is possible to compare the resistance of catalysts under conditions of high partial pressure.
The activity retention rate was calculated by the following formula (1). It can be said that the higher the activity retention rate of the catalyst, the more the decrease in activity is suppressed. It can be evaluated as a possible catalyst.

Hereinafter, the effects of the present invention will be shown with reference to Examples and Comparative Examples.

(Example 1)
When the FT synthesis reaction was carried out using the catalyst shown in Table 1A, the CO conversion rate was 42.5%, the CH ₄ selectivity was 6.8%, the CO ₂ selectivity was 0.2%, and the hydrocarbon having 5 or more carbon atoms. The productivity was 1.28 (kg-hydrocarbon / kg-catalyst / hour) and the activity retention rate was 66.5%.

(Example 2)
When the FT synthesis reaction was carried out using the catalyst shown in Table 1B, the CO conversion rate was 48.1%, the CH ₄ selectivity was 5.9%, the CO ₂ selectivity was 0.3%, and the hydrocarbon having 5 or more carbon atoms. The productivity was 1.47 (kg-hydrocarbon / kg-catalyst / hour) and the activity retention rate was 70.4%.

(Example 3)
When the FT synthesis reaction was carried out using a catalyst as shown in C in Table 1, the CO conversion rate was 48.8%, the CH ₄ selectivity was 5.9%, the CO ₂ selectivity was 0.2%, and the hydrocarbon having 5 or more carbon atoms. The productivity was 1.49 (kg-hydrocarbon / kg-catalyst / hour) and the activity retention rate was 72.9%.

(Example 4)
When the FT synthesis reaction was carried out using a catalyst as shown in D in Table 1, the CO conversion rate was 45.5%, the CH ₄ selectivity was 6.5%, the CO ₂ selectivity was 0.2%, and the hydrocarbon had 5 or more carbon atoms. The productivity was 1.37 (kg-hydrocarbon / kg-catalyst / hour) and the activity retention rate was 68.2%.

(Example 5)
When the FT synthesis reaction was carried out using a catalyst as shown in E in Table 1, the CO conversion rate was 49.5%, the CH ₄ selectivity was 5.8%, the CO ₂ selectivity was 0.2%, and the hydrocarbon had 5 or more carbon atoms. The productivity was 1.51 (kg-hydrocarbon / kg-catalyst / hour) and the activity retention rate was 75.6%.

(Example 6)
When the FT synthesis reaction was carried out using a catalyst as shown in F in Table 1, the CO conversion rate was 51.4%, the CH ₄ selectivity was 5.5%, the CO ₂ selectivity was 0.2%, and the hydrocarbon had 5 or more carbon atoms. The productivity was 1.56 (kg-hydrocarbon / kg-catalyst / hour) and the activity retention rate was 74.0%.

(Example 7)
When the FT synthesis reaction was carried out using a catalyst as shown in G in Table 2, the CO conversion rate was 65.1%, the CH ₄ selectivity was 4.9%, the CO ₂ selectivity was 0.4%, and the hydrocarbon having 5 or more carbon atoms. The productivity was 1.98 (kg-hydrocarbon / kg-catalyst / hour) and the activity retention rate was 70.5%.

(Example 8)
When the FT synthesis reaction was carried out using a catalyst as shown in H in Table 2, the CO conversion rate was 59.0%, the CH ₄ selectivity was 5.6%, the CO ₂ selectivity was 0.2%, and the hydrocarbon having 5 or more carbon atoms. The productivity was 1.78 (kg-hydrocarbon / kg-catalyst / hour) and the activity retention rate was 75.1%.

(Example 9)
When the FT synthesis reaction was carried out using the catalyst shown in Table 2 I, the CO conversion rate was 73.0%, the CH ₄ selectivity was 4.5%, the CO ₂ selectivity was 0.6%, and the hydrocarbon had 5 or more carbon atoms. The productivity was 2.24 (kg-hydrocarbon / kg-catalyst / hour) and the activity retention rate was 71.9%.

(Example 10)
When the FT synthesis reaction was carried out using a catalyst as shown in J in Table 2, the CO conversion rate was 72.7%, the CH ₄ selectivity was 4.7%, the CO ₂ selectivity was 0.6%, and the hydrocarbon had 5 or more carbon atoms. The productivity was 2.22 (kg-hydrocarbon / kg-catalyst / hour) and the activity retention rate was 72.6%.

(Example 11)
When the FT synthesis reaction was carried out using a catalyst as shown in K in Table 2, the CO conversion rate was 65.0%, the CH ₄ selectivity was 5.3%, the CO ₂ selectivity was 0.3%, and the hydrocarbon had 5 or more carbon atoms. The productivity was 1.97 (kg-hydrocarbon / kg-catalyst / hour) and the activity retention rate was 71.6%.

(Example 12)
When the FT synthesis reaction was carried out using the catalyst shown in L in Table 2, the CO conversion rate was 65.1%, the CH ₄ selectivity was 4.9%, the CO ₂ selectivity was 0.5%, and the hydrocarbon having 5 or more carbon atoms. The productivity was 1.98 (kg-hydrocarbon / kg-catalyst / hour) and the activity retention rate was 67.1%.

(Example 13)
When the FT synthesis reaction was carried out using a catalyst as shown in M in Table 2, the CO conversion rate was 49.5%, the CH ₄ selectivity was 5.8%, the CO ₂ selectivity was 0.3%, and the hydrocarbon having 5 or more carbon atoms. The productivity was 1.49 (kg-hydrocarbon / kg-catalyst / hour) and the activity retention rate was 78.8%.

(Comparative example 1)
When the FT synthesis reaction was carried out using a catalyst as shown in Table 3 N, a CO conversion rate of 48.7%, a CH ₄ selectivity of 5.9%, a CO ₂ selectivity of 0.3%, and a hydrocarbon having 5 or more carbon atoms. The productivity was 1.49 (kg-hydrocarbon / kg-catalyst / hour) and the activity retention rate was 58.1%.

(Comparative example 2)
When the FT synthesis reaction was carried out using the catalyst shown in O in Table 3, the CO conversion rate was 66.1%, the CH ₄ selectivity was 4.9%, the CO ₂ selectivity was 0.4%, and the hydrocarbon having 5 or more carbon atoms. The productivity was 2.02 (kg-hydrocarbon / kg-catalyst / hour) and the activity retention rate was 59.9%.

(Comparative example 3)
When the FT synthesis reaction was carried out using the catalyst shown in P of Table 3, the CO conversion rate was 71.3%, the CH ₄ selectivity was 4.7%, the CO ₂ selectivity was 0.2%, and the hydrocarbon having 5 or more carbon atoms. The productivity was 2.15 (kg-hydrocarbon / kg-catalyst / hour) and the activity retention rate was 60.8%.

(Comparative example 4)
When the FT synthesis reaction was carried out using the catalyst shown in Q of Table 3, the CO conversion rate was 39.8%, the CH ₄ selectivity was 6.9%, the CO ₂ selectivity was 0.3%, and the hydrocarbon having 5 or more carbon atoms. The productivity was 1.17 (kg-hydrocarbon / kg-catalyst / hour) and the activity retention rate was 59.6%.

(Comparative example 5)
When the FT synthesis reaction was carried out using the catalyst shown in R of Table 3, the CO conversion rate was 57.3%, the CH ₄ selectivity was 6.2%, the CO ₂ selectivity was 0.4%, and the hydrocarbon having 5 or more carbon atoms. The productivity was 1.72 (kg-hydrocarbon / kg-catalyst / hour) and the activity retention rate was 57.3%.

Claims (14)

A catalyst that produces hydrocarbons from syngas
A catalyst carrier containing silica as a main component is supported by a cobalt metal and a titanium oxide, or a cobalt metal and a cobalt oxide and a titanium oxide.
Hydrocarbons are produced from synthetic gases characterized in that the total content of each simple substance of sodium, potassium, calcium, and magnesium in the catalyst and each compound in terms of metal is 0.070% by mass or less. Catalyst. The synthesis according to claim 1, wherein the total content of each simple substance of sodium, potassium, calcium, and magnesium in the catalyst and each compound in terms of metal is 0.030% by mass or less. A catalyst that produces hydrocarbons from gas. The carrying ratio of the cobalt metal in the catalyst, or the carrying ratio of the cobalt metal and the cobalt oxide in the catalyst is 5 to 50% by mass in terms of cobalt metal, and the carrying amount of the titanium oxide in the catalyst. The claim is characterized in that the molar ratio (Ti / Co) of the supported amount of the cobalt metal in the catalyst or the supported amount of the cobalt metal and the cobalt oxide in the catalyst is 0.03 to 0.6. A catalyst for producing a hydrocarbon from the synthetic gas according to 1 or 2. The catalyst for producing a hydrocarbon from the synthetic gas according to any one of claims 1 to 3, wherein the catalyst carrier is spherical. The method for producing a catalyst for producing a hydrocarbon from a synthetic gas according to any one of claims 1 to 4, wherein a cobalt precursor and a titanium precursor are used as a catalyst carrier containing silica as a main component. By the impregnation method, a cobalt compound and a titanium compound are supported separately, and after each of the compounds is supported, a drying treatment, a drying treatment and a firing treatment, or a drying treatment, a firing treatment and a reduction treatment are performed to produce the compound. A method for producing a catalyst for producing a hydrocarbon from a characteristic synthetic gas. The synthetic gas according to claim 5, wherein when the cobalt compound and the titanium compound are supported by using the impregnation method, the titanium compound is first supported and then the cobalt compound is supported. A method for producing a catalyst for producing a hydrocarbon. The method for producing a catalyst for producing a hydrocarbon from a synthetic gas according to claim 5 or 6, wherein the cobalt precursor used in the impregnation method is cobalt acetate. Claim 5 is characterized in that the total content of each simple substance of sodium, potassium, calcium, and magnesium contained in the catalyst carrier and each compound as a metal equivalent is 0.080% by mass or less. A method for producing a catalyst for producing a hydrocarbon from the synthetic gas according to any one of Items to 7. The synthetic gas according to any one of claims 5 to 8, wherein the content of the simple substance of sodium and the compound contained in the catalyst carrier as a metal equivalent is 0.030% by mass or less. A method for producing a catalyst for producing hydrogen. When producing the catalyst carrier containing silica as a main component, the silica sol produced by mixing an alkaline alkali silicate aqueous solution and an acid aqueous solution is gelled, subjected to at least one of acid treatment and water washing treatment, and then calcined. The method for producing a catalyst for producing a hydrocarbon from a synthetic gas according to any one of claims 5 to 9, wherein the catalyst is produced. In at least one of the acid treatment and the washing treatment after gelation of the silica sol, the total content of each simple substance of sodium, potassium, calcium and magnesium and each compound as a metal equivalent is 0.06% by mass or less. The method for producing a catalyst for producing a hydrocarbon from a synthetic gas according to claim 10, wherein a certain water is used. The method for producing a catalyst for producing a hydrocarbon from a synthetic gas according to claim 10 or 11, wherein the gelation is formed by spraying the silica sol into a gas medium and forming it into a spherical shape. The silica-based catalyst carrier is washed with at least one of ion-exchanged water, acid, and alkali to reduce the concentrations of sodium, potassium, calcium, and magnesium, and then the cobalt compound and the titanium. The method for producing a catalyst for producing magnesium from a synthetic gas according to any one of claims 5 to 12, wherein the compound is supported. A method for producing a hydrocarbon from a synthetic gas, which comprises producing a hydrocarbon from a synthetic gas by a liquid phase reaction on a slurry bed using the catalyst according to any one of claims 1 to 4.