RU2487159C2 - Method of conducting fischer-tropsch process at low pressure - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention relates to versions of a method of conducting a Fischer-Tropsch process for producing liquid hydrocarbons mainly containing diesel fuel or a diesel mixture to obtain a liquid hydrocarbon product containing less than 10 wt % wax (>C23) and more than 65% of the (C9-C23) diesel fraction. One of the versions of the method includes the following steps: carrying out operations at pressure below 200 pounds per square inch (absolute); and using a cobalt catalyst having a Fischer-Tropsch support with cobalt metal crystallites on it, wherein the cobalt metal crystallites have average diameter greater than 16 nm.

EFFECT: invention is used to obtain a diesel fraction without further processing of the product.

38 cl, 8 tbl, 12 ex, 11 dwg

Description

FIELD OF THE INVENTION

In General, this invention relates to a method for implementing the Fischer-Tropsch process at low pressure to convert carbon monoxide and hydrogen into diesel fuel or a mixture of diesel fuel.

State of the art

The Fischer-Tropsch (FT) process for converting carbon monoxide and hydrogen into liquid motor fuel and / or wax has been known since 1920.

During World War II, synthetic diesel fuel was produced in Germany by gasifying coal and producing a mixture of hydrogen and carbon monoxide in a 1: 1 ratio to convert it into liquid fuel. Later in South Africa, due to trade sanctions and a lack of natural gas, a method was developed for gasifying coal into synthesis gas and using the Fischer-Tropsch iron catalyst in a fixed bed. Iron catalysts are very active in the water-gas shift reaction, in which the gas composition shifts from a hydrogen deficiency to an approximate optimum H ₂ / CO ratio of about 2.0. After large reserves of natural gas were discovered, steam and autothermal reforming units began to be used to produce synthesis gas, a feedstock for FT reactors with a suspended layer of cobalt or iron catalyst.

At gas-to-liquid conversion plants (GTL), a trade-off must be sought between the yield of the liquid product and the operational and capital costs. For example, if there is an electricity market, then you can choose a steam reforming unit, because this technology gives a large amount of heat: from the heat of fuel gas, you can get electricity using the “economizer” and a steam turbine. If preserving the source of natural gas and low capital costs are more important, then autothermal reformers or reformers of partial oxidation are preferred.

Another factor when choosing the most suitable type of reformer is the nature of the hydrocarbon feed. If the gas is enriched in CO ₂ , this is an advantage because the necessary H ₂ / CO ratio can be provided directly in the gas from the reforming unit without removing excess hydrogen, and part of the CO _{2 can be} converted to CO, which increases the potential amount of liquid hydrocarbons that can be obtained. In addition, the required volume of water vapor is reduced, which also reduces the technological energy costs.

The market for the implementation of the Fischer-Tropsch (FT) process is concentrated in large “world-class” plants with a natural gas supply rate of more than 200 million cubic feet per day. due to significant savings on a large scale production. These plants operate at high pressure, approximately 450 psi. inch, and exhaust gas recycle to the FT reactor is widely used. For example, at the Norsk Hydro plant, the recirculation ratio is approximately 3.0. The focus is on achieving maximum wax output. In terms of product composition, these large plants focus on the maximum yield of FT waxes in order to minimize the formation of C ₁ -C ₅ products. Then the waxes are hydrocracked and fractions of primary diesel fuel and gasoline are obtained. Unfortunately, light hydrocarbons are also formed. Reforming plants usually use some types of autothermal reforming with oxygen, which is obtained from the air in a cryogenic manner, which is very expensive in terms of capital and operating costs. A large-scale economy dictates the use of high working pressure, oxygen reforming of natural gas, a significant recycling of the exhaust gas to the FT reactor to increase the conversion of synthesis gas, regulation of heat removal and hydrocracking of the resulting wax. The project of an economical FT plant for small-tonnage production with a capacity of less than 100 million cubic feet / day. still not been developed.

The Fischer-Tropsch synthesis is usually called the catalytic hydrogenation of carbon monoxide to form a set of products from methane to heavy hydrocarbons (up to C ₈₀ or more), as well as oxygenated hydrocarbons. The resulting high molecular weight hydrocarbons are primarily normal paraffins that cannot be directly used as motor fuel, as they are not suitable for engines operating at low temperatures. After further hydrotreatment, the resulting hydrocarbons from the Fischer-Tropsch synthesis can be converted into more valuable products, such as diesel fuel, jet fuel or kerosene. Therefore, it is desirable to obtain directly the maximum amount of high-value liquid hydrocarbons so as not to carry out further component separation or hydrocracking.

As the Fischer-Tropsch catalysts, catalytically active elements of group VIII are used, in particular iron, cobalt and nickel; the most common catalyst systems are cobalt / ruthenium. In addition, the catalyst usually contains a support or carrier, as well as a promoter, for example rhenium.

Disclosure of invention

According to one embodiment of the invention, there is provided a method for carrying out the Fischer-Tropsch (FT) process in the presence of a cobalt catalyst with crystallites with an average diameter of more than 16 nm. In this case, liquid hydrocarbons are obtained containing less than 10 wt.% Wax (> C ₂₃ ) and more than 65% diesel fuel (C _9-23 ). In this method, a FT catalyst carrier is used, which is selected from the group consisting of alumina, zirconium oxide and silicon oxide. The cobalt catalyst contains more than 10 wt.% Cobalt. The operating pressure in the proposed method for implementing the Fischer-Tropsch process may be below 200 psi. inch (abs). In this case, promoters that are selected from the group consisting of ruthenium, rhenium, rhodium, nickel, zirconium, titanium and mixtures thereof can be used. To reduce the yield of the gasoline fraction, a single distillation is carried out. The method uses a FT reactor without recycle of exhaust gas. The method also uses a reforming unit in which the source of oxygen is air. The reactor may be a fixed bed FT reactor or a suspended catalyst bed reactor.

According to another embodiment of the invention, a FT method is provided at a pressure below 200 psi. inch (abs) using an air autothermal reformer with a CO conversion of at least 65% and a diesel yield of more than 60 wt.% in a single-pass FT reactor in the presence of a cobalt catalyst. The catalyst contains cobalt metal in an amount of more than 5 wt.% And rhenium in an amount of less than 2 wt.% On a support selected from the group consisting of alumina, zirconium oxide and silicon oxide. The cobalt catalyst consists of crystallites with an average diameter of more than 16 nm. The carrier for FT catalysts may be alumina. In this method, selective membranes or molecular sieves are used to remove hydrogen from the feed gas. Alternatively, the cobalt content of the catalyst may be more than 6 wt.% And the working pressure below 100 psi. inch (abs). In addition, the reactor may include a promoter that is selected from the group consisting of ruthenium and rhenium and mixtures thereof.

According to another embodiment of the invention, there is provided a FT method operating at a pressure below 200 psi. inch (abs) using an oxygen autothermal reforming unit with a CO conversion of at least 65% and a diesel yield of more than 60 wt.% in a FT reactor using a cobalt catalyst. The catalyst contains cobalt metal in an amount of more than 5 wt.% And rhenium less than 2 wt.% On a support selected from the group consisting of alumina, zirconia and silicon oxide. The cobalt catalyst consists of crystallites with an average diameter of more than 16 nm. The carrier for the FT catalyst may be alumina. In the method, the exhaust gas of the reforming unit is formed, which is partially returned to the reformer. Selective membranes or molecular sieves are used to remove hydrogen from the feed gas. Alternatively, the cobalt content of the catalyst may be more than 6 wt.% And the working pressure below 100 psi. inch (abs). In addition, the reactor includes a promoter that is selected from the group consisting of ruthenium or rhenium or mixtures thereof.

According to another embodiment of the invention, there is provided a FT method operating at a pressure below 200 psi. inch (abs), using an oxygen steam reforming unit with a CO conversion of at least 65% and a diesel yield of more than 60 wt.% in a FT reactor with a cobalt catalyst in which more than 5 wt.% cobalt metal and rhenium are present less than 2 wt.% on a carrier which is selected from the group consisting of alumina, zirconia or silica, or mixtures thereof. The cobalt catalyst consists of crystallites with an average diameter of more than 16 nm. The carrier for the FT catalyst may be alumina. Selective membranes or molecular sieves are used to remove hydrogen from the feed gas. In the method, off-gas from a reforming unit is generated, which is partially or completely burned to provide heat to the reforming unit. Alternatively, the cobalt content of the catalyst may be more than 6 wt.% And the working pressure may be below 100 psi. inch (abs). In addition, the reactor contains a promoter that is selected from the group consisting of ruthenium or rhenium or mixtures thereof.

According to another embodiment of the invention, there is provided a FT method operating at a pressure below 200 psi. inch (abs) using an air or oxygen partial oxidation reforming unit with a CO conversion of at least 65% and a diesel yield of more than 60 wt.% in a FT reactor with a cobalt catalyst containing more than 5 wt.% cobalt metal and rhenium in an amount of less than 2 wt.% on a FT catalyst support, which is selected from the group consisting of alumina, zirconia and silicon oxide. The cobalt catalyst consists of crystallites with an average diameter of more than 16 nm. The carrier for the FT catalyst may be alumina. Selective membranes or molecular sieves are used to remove hydrogen from the feed gas. In the method, off-gas from the reforming unit is generated, which is partially or completely burned to supply heat to the reforming unit. Alternatively, the cobalt content of the catalyst may be more than 6 wt.% And the working pressure may be below 100 psi. inch (abs). In addition, the reactor contains a promoter that is selected from the group consisting of ruthenium or rhenium or mixtures thereof.

Brief Description of the Drawings

The figure 1 presents a block diagram of a method according to one of the variants of the present invention;

Figure 2 is a block diagram of a single separation of a gasoline fraction and diesel hydrocarbons as a subsequent Fischer-Tropsch synthesis step;

Figure 3 represents the distribution of C5 + hydrocarbons by the number of carbon atoms for the catalyst of Example 3 (trefoils) at 190 ° C;

Figure 4 represents the effect of pressure on the activity of the catalyst of example 4;

Figure 5 represents the distribution of C5 + hydrocarbons by the number of carbon atoms for the catalyst of Example 7 at 190 ° C., 70 psi. inch (abs);

Figure 6 represents the distribution of C5 + hydrocarbons by the number of carbon atoms for the catalyst of Example 8a (LD-5) at 200 ° C, 70 psi. inch (abs);

Figure 7 represents the distribution of C5 + hydrocarbons by the number of carbon atoms for the catalyst of Example 9 (F-220) at 190 ° C., 70 psi. inch (abs);

Figure 8 represents the distribution of C5 + hydrocarbons by the number of carbon atoms for the catalyst of Example 10 using the ruthenium promoter;

Figure 9 represents the distribution of C5 + hydrocarbons by the number of carbon atoms for the catalyst of Example 11 (Aerolyst 3038 silica);

Figure 10 represents the wax content in the C5 + hydrocarbons FT method, depending on the size of the cobalt crystallites in the catalyst; and

Figure 11 represents the distribution of hydrocarbons by the number of carbon atoms obtained on the catalyst of example 9 in comparison with the expected dependence for the traditional Anderson-Schulz-Flory distribution.

* In all figures with the distribution of hydrocarbons by the number of carbon atoms, the gasoline fraction is indicated by large squares, diesel fuel by rhombuses and light waxes by small squares.

The implementation of the invention

Introduction

The activity of supported cobalt catalysts in the Fischer-Tropsch reaction depends on various parameters, including the size and shape of cobalt crystallites. The size of metal crystallites determines the number of active centers available for reduction (dispersion), and the degree of reduction.

Under certain conditions of pretreatment and activation, as a result of strong interaction between cobalt metal and an oxide support, undesirable cobalt compounds are formed with the support, for example cobalt aluminate, which is reduced only at high temperatures. A high reduction temperature can lead to sintering of cobalt crystallites and the formation of larger clusters of metallic cobalt. Heat treatment, the nature of the metal precursor and the metal content, as well as metal promoters, affect the size of cobalt crystallites. At a low content of metallic cobalt, the dispersion of the metal is large and the crystallites are small in size, but the interaction of the metal with the support is enhanced, which leads to a low degree of reduction and low activity of the catalyst.

The activity of supported cobalt catalysts in the hydrogenation of carbon monoxide increases in proportion to the number of available cobalt atoms. Therefore, an increase in the dispersion of metallic cobalt naturally increases the catalytic activity and selectivity for C5 + hydrocarbons. However, small cobalt crystallites strongly interact with the oxide carrier and form non-reducible cobalt-carrier systems. A strong correlation between the crystallite size of cobalt metal and their reduction ability affects the catalytic activity, so that undesired reaction products can form as a result. Under typical conditions of the Fischer-Tropsch reaction, cobalt crystallite sizes in the range (9-200 nm) and dispersion in the range (11-0.5%) have a weak effect on the selectivity for C5 + hydrocarbons. However, smaller cobalt crystallites are noticeably deactivated. In 2000, Barbie et al. Studied the correlation between the deactivation rate and cobalt crystallite size and found a peak at 5.5 nm.

Variants of the invention

The following embodiments of the invention relate to a method for carrying out the Fischer-Tropsch process at low pressure and to a catalyst that achieves a high yield of diesel fraction. The pressure may be below 200 psi. inch (abs). The catalyst is cobalt deposited in an amount of more than 5 wt.% On gamma-alumina, optionally together with rhenium or ruthenium in an amount of 0.01-2 wt.%, And contains crystallites with an average diameter of more than 16 nm. It was found that this catalyst is very effective at low pressures in the conversion of synthesis gas to diesel fuel with a high yield, and liquid hydrocarbons contain less than 10 wt.% Wax (> C ₂₃ ) more than 65% of diesel fuel (C ₉ -C ₂₃ ) . The proposed options are particularly suitable for the conversion at low pressure of gases containing low molecular weight hydrocarbons into liquid FT products. Examples include landfill biogas, associated petroleum gas and low pressure gas from pressure relief gas fields. In all cases, in traditional FT plants it is necessary to carry out multi-stage compression of gas and air. The high efficiency of the proposed catalyst FT provides a high conversion of CO and gives a product stream containing up to 90 + wt.% Diesel fuel in one pass. By using air in a natural gas reforming unit, synthesis gas containing about 50% nitrogen is obtained, which facilitates the removal of heat from the heat-sensitive FT reactor and increases the gas velocity and heat transfer efficiency, so that gas recycling becomes unnecessary. The gasoline fraction can be partially separated from hydrocarbons by a low-cost single distillation operation to produce cleaner diesel fuel. This also provides some cooling of the reaction product. The resulting liquid hydrocarbons are quite suitable for mixing with petroleum diesel fuel in order to increase the cetane number and reduce the sulfur content.

The proposed options can be used both at world-wide plants for converting gas to liquid, and at small FT plants with a capacity of less than 100 million cubic feet per day. Regarding the application of FT to such small installations, the proposed embodiments are intended to optimize the economy, with emphasis on simplifying technology and minimizing capital costs, possibly due to efficiency. The existing FT technologies are compared with the proposed option for small FT installations:

Existing FT Technologies Suggested Options Large plants> 25 million Small plants <100 million cubic foot / day cubic foot / day High pressure> 200 psi Low pressure <200 inch (abs) psi inch (abs) Reformer oxygen supply Reformer air supply High recycling rate in No recirculation FT reactor or reformer ("Single pass" method) Low FT conversion of CO in one High conversion in one pass (<50%) pass (> 65%) Intentional significant less than 10% wax production getting wax Hydrocracking Waxes No hydrocracking FT multi-pass reactors FT single pass reactor Low diesel yield High diesel output (<50%) fuel (55-90% of liquid hydrocarbons)

To ensure high conversion in the FT method, when supplying synthesis gas from an oxygen reformer, a significant off-gas recycle was usually maintained with a circulation ratio of 3.0 or higher, based on fresh gas supply. The advantage of the proposed method is that the fresh gas supplied is diluted with carbon monoxide, which reduces the rate of heat removal from the FT reactor, reduces the possibility of formation of superheat points in the reactor and improves the composition of the reaction products. In contrast, off-gas recycling requires high capital costs and energy. The release of oxygen from the air is also very energy consuming and expensive.

In the proposed method, air is supplied to the reformer, therefore, the synthesis gas contains about 50% of an inert diluent, nitrogen, which eliminates the need for recycle exhaust gas and reduces the requirements for heat removal from the FT reactor. In other cases, the use of synthesis gas after air purging in the FT method reached the desired high values of CO conversion in complex serial FT reactors, which requires large capital costs and complex control. In the proposed method, a high conversion of CO is achieved in a simple single-pass reactor with a high yield of diesel fraction due to the use of a special catalyst, which is discussed in more detail below.

In one embodiment, the catalyst comprises a support — alumina — at a high cobalt concentration and low rhenium concentration to facilitate catalyst recovery. At high cobalt concentrations, catalytic activity increases and a high conversion of synthesis gas is achieved in one pass. The catalyst is prepared in such a way that it contains relatively large cobalt crystallites, which provides high selectivity for diesel fuel.

The Anderson-Schulz-Flori theory predicts that FT hydrocarbons contain carbon atoms in a wide range from 1 to 60, while diesel is the most desirable product (C ₉ -C ₂₃ , Chevron definition). To reduce the consumption of CO for the formation of C ₁ -C ₅ hydrocarbons, the general approach is to obtain as much wax as possible in the FT reactor and then, at a separate stage, carry out hydrocracking of the wax with the formation of mainly diesel fuel and gasoline fraction. The authors unexpectedly found that the proposed method and the catalyst according to the proposed options allow to obtain diesel fuel with a high yield (up to 90 wt.%) Directly in the FT reactor, which eliminates the need for expensive and complex hydrocracking.

Due to the ability to exclude oxygen purification, compression to high pressure, off-gas recycle and hydrocracking, this method can be economically applied on smaller scale plants than in the previously proposed FT technology options.

The figure 1 shows the flowchart of the FT method according to the present embodiment, in which the letters AK mean the following:

A - raw gas containing hydrocarbons

B - hydrocarbon gas processing equipment

C - reformer

D - water

E - oxidizing gas F Refrigerator G Separator

H — hydrogen removal (optional)

I - Fischer-Tropsch reactor

J - back pressure regulator

K - cooling and isolation of products (2 positions)

The letter A indicates the supplied hydrocarbon feed. It can be obtained from various sources: for example, it can be natural gas, biogas from landfills, associated gas from oil refining, etc. Gas pressure for this method can vary over a wide range from atmospheric pressure to 200 psi. inch (abs) or higher. Depending on the pressure source and the required operating pressure, one-stage or two-stage compression may be required. For example, biogas pressure is usually close to atmospheric and blowers are used to pump gas to the combustion apparatus. Associated gas, which is usually burned, should also be compressed to the desired operating pressure. There are also many long-exploited and nearly depleted natural gas fields with too low a pressure to pump it through pipelines as raw materials for the present process. The pressure in other sources of natural gas, which may or may not be removed from existing pipelines, may be the same or higher than the required working pressure for this method, and therefore they can also be considered suitable sources. Another candidate is natural gas, which contains too much inert component such as nitrogen, which does not correspond to the operating conditions of pipelines.

The letter B indicates the equipment for processing hydrocarbon gas. The gas must be cleaned to remove components that could interfere with the operation of the reforming unit or FT catalyst. Examples include mercury, hydrogen sulfide, silicones, and organic chlorides. Organic chlorides that may be present in biogas form hydrochloric acid in the reformer, which causes significant corrosion. Silicones form a continuous silicon dioxide film on the catalyst that blocks pores. Hydrogen sulfide is a strong poison for FT catalyst, and is usually removed to a content of 1.0 ppm. or less. Some gases do not require treatment (purification).

The concentration of hydrocarbons in the feed determines the economics of the process, since less hydrocarbons are formed from the same amount of feed. However, this method can work at a methane concentration of 50% or lower, for example, using biogas. There may be reasons why the method must be applied even with financial losses; for example, to solve the problem of greenhouse gases or to develop corporate standards for emissions. The method can work on raw materials containing only methane or liquid natural gas, using known reforming technologies. The presence of carbon dioxide in the feed has a positive effect.

The letter C denotes a reforming unit, which can be of several types, depending on the composition of the raw material. A significant advantage of low pressure operation is the reduced Brouard reaction rate and reduced metal dust formation.

Partial oxidation reforming units typically operate at very high pressures, such as 450 psi. inch (abs) or higher, which is not optimal for the FT process at low pressure. This reaction is energetically inefficient and can easily lead to the formation of soot, however, it does not require water and produces synthesis gas with a H ₂ / CO ratio close to 2.0, which is optimal for FT catalysts. The partial oxidation reforming units may be used in the present process.

The steam reforming units of the road cost and for maximum efficiency of large enterprises require the removal of heat from fuel gas. Since synthesis gas contains an inert gas such as nitrogen at a relatively low concentration, it is difficult to control the temperature in the FT reactor unless recirculation of part of the off-gas to the FT reactor is applied. However, due to the low concentration of inert gas, it is possible to recycle part of the exhaust gas into the side pipe of the reformer through which the source of natural gas is supplied, or into a jacket for supplying heat. Bearing in mind that FT exhaust gas should in any case be burned before purging, this energy can be used to generate electricity or, even better, to supply heat to the reforming unit, which is otherwise obtained by burning natural gas. For small FT plants, steam reforming plants are a good choice. Steam reforming units can be used in the present process.

Autothermal reforming is quite effective at a relatively moderate capital cost. At medium temperatures and low concentrations of water vapor, it converts gaseous raw materials with a low CO ₂ content into a soot-free synthesis gas with an H ₂ / CO ratio of about 2.5, which is closer to the desired ratio than in the case of steam reforming. However, it is still necessary to remove part of the hydrogen from many sources of natural gas. If the feed contains more than about 33% CO ₂ , as in the case of biogas, then a H ₂ / CO ratio of 2.0 can be achieved without recycling flows and water consumption can also be reduced. This type of reformer is most suitable for the proposed low pressure FT methods.

The letter D indicates optional water that is supplied to the reforming unit in the form of water vapor. All reforming technologies, with the exception of partial oxidation, require steam to be supplied.

The letter E denotes an oxidizing gas, which may be air, oxygen, or oxygen enriched air.

The letter F denotes a refrigerator to reduce the temperature at the outlet of the reforming unit from above 700 ° C to close to room temperature. Cooling can be carried out in several stages, but it is preferable to do this in one step. You can cool using shell, tubular, plate or frame heat exchangers. Cooling can be combined with the use of the resulting energy to preheat the gas supplied to the reforming unit, as is well known in the industry. Another method of cooling the exhaust gas of a reforming unit is to directly supply water to a stream passing through water in a vessel.

The letter G denotes a separator for separating synthesis gas from the reforming unit from condensed water to minimize the amount of water entering the subsequent apparatus.

The letter H indicates optional hydrogen removal equipment, such as hydrogen-selective Prism ™ membranes from Air Products or cynara membranes from Natco.

Some reforming methods produce synthesis gas that is excessively enriched with hydrogen, which must be partially removed to achieve optimal FT reactor operation. The ideal H ₂ / CO ratio is 2.0-2.1, while in the raw synthesis gas this ratio can be 3.0 or higher. A high concentration of hydrogen leads to increased CO losses for the formation of methane instead of the desired motor fuel or a precursor of motor fuel such as a gasoline fraction.

The letter I denotes typical FT reactors, which are fixed bed reactors or bubbled bed reactors, and both types of such reactors can be used. However, in small installations, a fixed bed reactor is preferred because of its ease of regulation and ease of scaling.

The letter J denotes a back pressure regulator that maintains the desired pressure in the flow chart. It can be placed elsewhere, depending on the location of the products and the possible methods of partial separation of products.

The letter K indicates the cooling of reaction products and their isolation. Products are usually cooled by heat exchange with cold water and use heat to preheat the water used in the FT installation. The separation is carried out in a separator for the separation of oil and water. However, an alternative is the rapid cooling of the FT reactor to the specified refrigerator-separator, as shown in figure 2. This has two objectives: firstly, to lower the temperature of the reaction products and, secondly, to partially separate the gasoline fraction from the obtained products, enriching the remaining liquid with components diesel fuel.

The figure 2 shows a diagram of a method with a single separation of the gasoline fraction and diesel fuel, in which:

1 - fixed-bed Fischer-Tropsch reactor;

2 - a mixture of gases, water, oil fraction, diesel fuel and light waxes at about 190-240 ° C and pressure above atmospheric;

3 - overpressure valve;

4 - stream 2 at a reduced temperature as a result of gas expansion and at a pressure of 14.7 psi. inch (abs);

5 - evaporation vessel;

6 - vapor phase, which consists of stream 2 and does not contain diesel fuel and light waxes;

7 - refrigerator;

8 - stream 6 with a gasoline fraction and water in the liquid phase;

9 - a vessel for storing gasoline fraction and water;

10 - exhaust gas stream, consisting mainly of inert gases and light hydrocarbons.

The flow of FT reaction products at number 2 passes through the overpressure valve 3 into the evaporation vessel 5. Inert gases and low boiling hydrocarbons, water and oil fraction enter the overhead as it evaporates from the evaporation vessel through the refrigerator 7. Diesel fuel and light waxes are collected in the vessel 5. Water and gasoline fraction are condensed in the refrigerator 7 and collected in the vessel 9. The remaining gases are released in the overhead stream in stream 10 and are usually burned, sometimes with the release of energy, or used to generate electricity.

EXAMPLES

Used media for catalysts

Table 1 Physical Characteristics of Catalyst Carriers Alumina (supplier data) Alcoa LD-5 Alcoa CSS-350 Alcoa F-220 Sasol Shamrock Degussa Aerolyst 3038 The value of the surface, m ² / g 300 min 350 360 248 270 The average particle size, microns different 2120 2000 1670 × 4100 2500 Pore volume, cm ³ / g 0.63 0.57 0.5 0.82 0.9-1.0 Bulk density, g / cm ³ 0.645 0.72 0.769 0.42 0.40-0.46 A1 ₂ O ₃ , wt.% different 99.6 93.1 different <500 ppm SiO ₂ , wt.% 0.40 max. 0.02 0.02 0.015 > 99.8 Fe ₂ O ₃ , wt.%, Max. 0.04 " 0.02 0.015 <30 ppm Na ₂ O, wt.%, Max. 0.2 0.35 0.3 0.05 - LO1 (250-1100 ° C), wt.% 23-30 3.5 6.5 - -

Example 1

The catalyst was prepared by a method well known in the art. The catalyst carrier was an alumina extrudate in the form of a trefoil from Sasol Germany GmbH (hereinafter referred to as “trefoil”). The extrudate was 1.67 mm in diameter and 4.1 mm in length. The carrier was calcined in air at 500 ° C for 24 hours. A mixed solution of cobalt nitrate and rhenium acid was added to the carrier in terms of moisture capacity; the final catalyst contained 5 wt.% metallic cobalt and 0.5 wt.% metallic rhenium (catalyst 1). The catalyst was oxidized in three stages:

Stage 1: the catalyst was heated to 85 ° C and held for 6 hours;

Stage 2: the temperature was increased to 100 ° C at a rate of 0.5 ° C per minute and held for 4 hours;

Stage 3: the temperature was increased to 350 ° C at a rate of 0.3 ° C per minute and held for 12 hours.

The drying rate of the wet catalyst depends on the particle size of the catalyst. Smaller particles dry out much faster than larger ones, and the size of the crystals formed in the pores depends on the rate of crystallization. The oxidized catalyst with a volume of 29 cm ^{3 was} loaded into tubes with an external diameter of 14 inches and an annular external space through which pressure water flows to control the temperature, which removes the heat of reaction. The FT reactor is a tubular heat exchanger, in the inner tubes of which there is a catalyst. The incoming gas and water have a predetermined temperature for the reaction. The catalyst recovery is carried out as follows:

The flow rate of the reducing gas (cm ³ / min) / N ₂ in nitrogen (%) / temperature (° C) / time (hour):

1) 386/70/200/4, stage pre-heating;

2) 386/80 / to 325/4, the stage of slow heating;

3) 386/80/325/30, stage constant temperature.

During the catalysis of the Fischer-Tropsch reaction, the total gas flow rate into the FT reactor was determined by the GHSV value of 1000 hours 1. The gas composition corresponded to the gas composition of the air autothermal reformer: 50% nitrogen, 33.3% H ₂ and 16.7% CO. To reduce the formation of methane, the catalyst was kept at a reactor temperature of 170 ° C for the first 24 hours. Apparently, this method leads to carbonylation of the cobalt surface and increases the activity of the FT catalyst. The conversion of CO and the yield of liquid products were determined at different temperatures in the range from 190 to 220 ° C.

Example 2

In this example, the same catalyst (catalyst 2) was used as in example 1, except that the content of cobalt metal was 10 wt.%.

Example 3

In this example, the same catalyst (catalyst 3) was used as in example 1, except that the content of metallic cobalt was 15 wt.%.

Example 4

In this example, the same catalyst (catalyst 4) was used as in example 1, except that the content of metallic cobalt was 20 wt.%.

Example 5

In this example, the same catalyst (catalyst 5) was used as in example 1, except that the content of metallic cobalt was 26 wt.%.

Example 6

In this example, the same catalyst (catalyst 6) was used as in example 1, except that the content of cobalt metal was 35 wt.%.

Example 7

In this example, the same catalyst (catalyst 7) was used as in example 1, except that the alumina support was CSS-350 from Alcoa and the cobalt content was 20% by weight. The carrier had the form of spherical particles with a diameter of 1/16 inch.

Examples 8a. 8b. 8s and 8d

In this example, the same catalysts (catalysts 8a, 8b, 8c and 8d) were used as in example 1, with the exception of the following: catalyst 8a was identical to catalyst 1 except that the carrier was LD-5 alumina from Alcoa containing cobalt 20 wt.%. This carrier is a spherical particle with an average particle size of 1963 microns. Example 8a used a mixture of particles with different sizes. Part of the initial particles was crushed to smaller particles: catalysts 8b, 8c and 8d were prepared from particles with diameters of 214, 359 and 718 μm, respectively. The cobalt content in examples 8b, 8c and 8d was the same as in catalyst 8a.

Example 9

In this example, the same catalyst (catalyst 9) was used as the catalyst in example 1, except that the alumina support was Alcoa grade F-220 with a cobalt content of 20% by weight. The carrier F-220 consists of spherical particles with a sieve size distribution of 7/14.

Example 10

In this example, the same catalyst (catalyst 10) was used as catalyst 4, except that the promoter was ruthenium and not rhenium.

Example 11

In this example, the same catalyst (Catalyst 11) was used as Catalyst 3, except that instead of alumina, silica was used - carrier Aerolyst 3038 from Degussa.

Example 12

In this example, the same catalyst (catalyst 12) was used as catalyst 8d, with the same support, particle size and catalyst content, except that the oxidation took two times longer than the synthesis of the catalyst. The temperature was maintained for 12, 8, and 24 hours in 3 oxidation stages, respectively, as described for catalyst 1. The oxidation rate of catalyst 12 with small particles was reduced in order to obtain larger cobalt crystallites (21.07 nm) in the pores of small support particles compared to crystallite sizes obtained during faster crystallization of catalyst 8d (15.72). The method used here to control the drying rate and sizes of cobalt crystallites in the catalyst does not mean abandoning any other method for producing larger crystallites. For example, you can control the drying speed of the catalyst and, consequently, the size of the cobalt crystallites by varying the relative humidity or pressure in the drying chamber.

Catalyst Characterization

For these catalysts, the average crystallite size (d (Co0), dispersion (D%) and degree of reduction (DOR) were determined on a Chembet 3000 TPV / turbojet analyzer (Quantachrome Instruments). The catalyst was restored at 325 ° C in a stream of H ₂ and cobalt dispersion was calculated assuming that one molecule of hydrogen falls into two at the surface of the cobalt atom. Identified oxygen chemisorption using a series of pulses (O ₂ / He) supplied to the catalyst at a temperature of 380 ° C after reduction of the catalyst at 325 ° C. Determine the number of moles of absorbed sour ode and the calculated degree of reduction in the assumption that all the cobalt metal has been oxidized in a CO ₃ O _4, cobalt crystallite size was calculated using the formula.:

d (Co0) = (96 / D%) DOR

D%: Dispersion

FT catalyst evaluation

(i) Effect of cobalt content

The effect of Co content on the catalytic activity was studied in examples 1-6, and the results are shown in table 2.

table 2 The effect of cobalt content on the activity of the catalyst in examples 1-6 (trefoil) at 70 psi. inch (abs) Cobalt, wt.% (Example number) 8 (1) 10 (2) 15 (3) 20 (4) 26 (5) 35 (6) Optimum temperature, ° С 220 210 205 200 200 200 The rate of production of liquid hydrocarbons, ml / hour 0.09 0.54 0.74 1.03 0.77 0.86 Gasoline fraction, wt. about. 6.4 8.8 13.9 17.9 16.4 15.8 Diesel fraction, wt.% 92.8 89.8 78.3 75.3 76.8 76.8 Light wax, wt.% 1.1 8.4 7.8 6.9 6.6 7.4 Receiving diesel fuel, ml / hour 0.08 0.45 0.58 0.78 0. 59 0.66 The conversion of CO, mol. % 19.4 42.0 61.2 86.1 82.8 83.1 Selectivity for C5 +,% 28.6 80.6 71.3 68.0 65.1 64.3 Cetane number 81 79 77 76 74 75

In each of examples 1-6, experiments were carried out at different temperatures and the temperature was determined at which the greatest amount of hydrocarbons was obtained. Obviously, 5% cobalt is not enough to produce a significant amount of liquid hydrocarbons: the best concentration was 20 wt.% Co, at which 1.03 ml / h of liquid hydrocarbons were obtained. The concentration of the diesel fraction in the obtained hydrocarbons was 75.3-92.5% with a cobalt content of 10 wt.% Or higher. The highest diesel production rate (0.78 ml / hr) was achieved on a trefoil carrier with a cobalt content of 20% and a pressure of 70 psi. inch (abs).

The data on the activity of catalyst 1 at 202.5 ° C are given in table 8. The wax concentration (> C ₂₃ ) in C5 + liquid hydrocarbons was only 6.8%, and the diesel fraction was 73.5% (C ₉ -C ₂₃ ). It was found that on all the studied catalysts with an average crystallite diameter of more than 16 nm received less than 10 wt.% Wax in the composition of C5 + hydrocarbons, which allows the product to be used directly as a diesel fuel mixture.

The figure 3 shows the distribution of the number of carbon atoms on the catalyst 3 (trefoil) in example 3 at 190 ° C. The reaction product has a very narrow hydrocarbon distribution and does not contain heavy wax. The yield of diesel fuel was 90.8%, gasoline fraction 6.1% and light waxes 3.1%. The cetane number was very high and reached 88. On all the graphs of the distribution by the number of carbon atoms, the gasoline fraction is indicated by large squares, diesel fuel by rhombuses and light waxes by small squares.

Pressure effect

The catalyst 4 in example 4 was tested under standard conditions, as described above, at a temperature of 202.5 ° C and various pressures. The results presented in table 3 and figure 4 show that the performance of the catalyst for liquid hydrocarbons was significant at low pressures, up to 70 psi, and optimal results were obtained in the range of 70-175 psi (abs). Preferred are pressures of 70-450 psi (abs) and most preferred are 70-175 psi (abs). The output of the diesel fraction in this pressure range was almost constant at the level of 70.8-73.5 wt.%. As shown in table 8, the product obtained on catalyst 4 with 20 wt.% Cobalt, an average crystallite size of 22.26 nm and a C5 + fraction with wax in an amount of 6.8 wt.%, Can be used in a mixture for diesel fuel.

Table 3 The effect of pressure on the activity of the catalyst (catalyst 4, 202.5 ° C) Pressure, psi inch (abs) 40 70 one hundred 125 140 175 200 The rate of production of liquid hydrocarbons, ml / hour 0.405 1.047 1.082 1.034 1.046 1.079 0.805 Gasoline fraction, wt.% 8.5 19.7 24.7 23.5 23.9 26.6 23.9 Diesel fraction, wt.% 77.8 73.5 71.9 73.1 73.4 70.8 74.1 Light wax, wt.% 13.7 6.8 3.4 3.4 2.7 2.6 2.0 Receiving diesel fuel, ml / hour 0. 32 0.77 0.78 0.76 0.77 0.76 0.60 The conversion of CO, mol. % 59.4 90.2 84.1 83.8 74.8 73.4 65.8 Selectivity for C5 +,% 76.6 58.1 54.4 52.5 61.3 57.7 52.0

Catalyst 7

As can be seen in table 4, the maximum speed of diesel fuel was achieved at 215 ° C and 70 psi. inch (abs). Compared with catalyst 4 on catalyst 7, the rate of production of diesel fuel at the optimum temperature (215 ° C) was lower, but with an increased yield of the fraction of diesel fuel. Figure 5 shows a narrow range of the distribution of liquid products by the number of carbon atoms at 190 ° C, and the range for diesel fuel was 89.6%. The cetane number was 81. However, as shown in table 8, the crystallite size was 18.2 6 nm, and the wax fraction was 7.2%, which allows the product to be used as a diesel fuel mixture.

Table 4 Catalyst 7 Performance at Different Temperatures (CSS-350) Temperature ° C 190 200 210 215 220 The rate of production of liquid hydrocarbons, ml / hour 0.55 0.58 0.64 0.70 0.68 Gasoline fraction, wt.% 5.4 15,2 13.4 15.4 14.3 The fraction of diesel fuel, wt.% 89.6 76.8 82.0 77.4 81.3 Light wax, wt.% 5.0 8.0 4.6 7.2 4.4 Receiving diesel fuel, ml / hour 20.1 47.2 45.2 53.8 49.5 Average molecular weight 194.9 170.2 171.2 164.8 168.2 The conversion of CO, mol.% 47.8 53.4 81.6 93.8 100.0

Catalysts 8a, 8b. 8 s and 8d

The test results are shown in table 5. It was found that the dispersion of metallic Co in catalysts 8b, 8c and 8d is higher than in catalyst 8a. On catalysts containing Co ⁰ crystallites with average sizes of less than 16 nm, a large wax fraction in the amount of 17.6–19.3 wt% is formed in FT products, while on catalyst 8a and catalyst 12 containing Co ⁰ crystallites more than 16 nm, less C5 + liquid products form less wax at 6.6 and 7.8 wt.%, respectively, which allows the product to be used in a mixture of diesel fuel. It was noted that catalysts 8a and 12 contain particles of different sizes, but the yields of the wax fraction on them are equally low. This shows that the parameter controlling the production of low concentrations of wax is the crystallite size, not the particle size.

Table 5 Catalyst Performance 8a-8d 12 at 70 psi inch (abs) Catalyst 8a 12 8b * 8 s * 8d * The average particle size, microns 1963 718 274 359 718 The average crystallite size, nm 06/23 07/21 9.19 14.76 15.72 Dispersion,% 4.16 4.56 10.45 6.5 6.11 Fischer-Tropsch test temperature, ° С 200 205 200 200 200 The composition of the fraction C5 +, wt.% Gasoline fraction (number of carbon atoms C ₆ -C ₈ ) 9.3 16.7 10.1 10.4 11.4 Diesel fuel (number of carbon atoms C ₉ -C ₂₃ ) 84.1 76.5 70.9 72 69.3 Wax (number of carbon atoms
> C ₂₃ ) 6.6 7.8 19.0 17, 6 19.3 Average molecular weight, AMU 182 160 195 190 193 Conversion% 62.7 51.2 68.8 72.7 69.3

* Not included in this application

Catalyst 9

Catalyst 9 was tested at a pressure of 70 psi. inch (abs). As shown in table 6 and figure 7, the hydrocarbons obtained at 190 ° C. contained 99.1% of the “gasoline fraction plus diesel fuel”. The amount of diesel fuel itself was 93.6%. Received very little wax. The cetane number is 81. As shown in table 8, the crystallite size was 22.22 nm and the wax fraction was 2.3%, which allows the resulting product to be used directly as diesel fuel.

Table 6 Catalyst 9 (F-220) Performance at Different Temperatures (70 psi (Abs) Pressure) Temperature ° C 190 200 210 215 The rate of production of liquid hydrocarbons, ml / hour 0.465 0.757 0.8 0.733 Gasoline fraction, wt.% 5.5 9.2 20.1 21.5 Diesel fraction, wt.% 93.6 88.5 77.0 74.7 Light wax, wt.% 0.9 2.3 2.9 3.8 Receiving diesel fuel, ml / hour 0.41 0.62 0.53 0.47 Average molecular weight 188.2 181.4 157.7 154.1 The conversion of CO, mol. % 50.0 72.2 94.7 92.2 Cetane number 81.0 76.0 67.0 65.0

Catalyst 10

The data in table 7 and figure 8 show that the use of a ruthenium promoter in the catalyst instead of rhenium also leads to a narrow distribution of hydrocarbons with a diesel yield of 74.42% and a total cetane number of 78. As shown in table 8, the crystallite size was 20.8 9 nm and the content of the wax fraction 3.73%, which allows the use of the product in a mixture of diesel fuel.

Table 7. The operation of the catalyst 10 (ruthenium promoter, carrier aluminum oxide LD-5).

Temperature, ° C / Pressure, psi inch (abs) 215 Conversion% 94.64 The rate of production of liquid products C5 +, ml / hour 73 Diesel production rate, ml / hour 0.54 Fraction C5 +, wt.%: Gasoline fraction (C ₆ -C ₈ ) 21.86 Diesel fuel (C ₉ -C ₂₃ ) 74.42 Wax (> C ₂₃ ) 3.73 Cetane number 78 Average molecular weight 164

Catalyst 11

The rate of production of liquid hydrocarbons on catalyst 11 was 0.55 ml / h at 210 ° C. The distribution curve of the number of carbon atoms shown in figure 9 showed a narrow distribution with a large fraction of the fraction of diesel fuel. As shown in table 8, the crystallites had a size of 33.1 nm and the wax fraction was 5.2%, which allows the product to be used as a diesel fuel mixture, possibly after distillation of the gasoline fraction.

Table 8 The effect of cobalt crystallite size on the concentration of wax in the C5 + fraction Catalyst number four 7 9 10 eleven 12 Mark Trilist
Nick CSS-I
350 F-220 LD-5 / Ru Aerolyst
3038 LD-5 The average crystallite size, nm 22.26 18.26 22.22 20.89 33.10 07/21 Dispersion,% 4.31 5.26 4.32 4.60 2.90 4.56 Test temperature FT, ° С 202.5 215 200 215 200 205 Fraction C5 +, wt.%: Gasoline fraction (C ₆ -C ₈ ) 19.7 15.4 9.2 21.9 20.7 157 Diesel fuel (C ₉ -C ₂₃ ) 73.5 77.4 88.5 74,4 74.1 76.5 Wax (> C ₂₃ ) 6.8 7.2 2.3 3.7 5.2 7.8 Average molecular weight, AMU 165 165 181 164 147 160 CO conversion,% 90.2 93.8 72.2 92.6 57 51.2

Testing of catalysts 1-12 (with the exception of catalysts 8b, c and d) showed that a narrow hydrocarbon distribution, mainly in the diesel fraction region, with a low wax content (<10 wt.%), Is achieved when the FT catalyst contains cobalt crystallites larger than 16 nm, as shown in figure 10 (large squares are not part of this option). In the case of small catalyst particles (for example, in catalyst 12), to achieve the desired crystallite size, it is necessary to control the crystallization rate. In FIG. 11, this result was compared with the distribution by the number of carbon atoms expected by the Anderson-Schulz-Flory equation (A-SF) based on carbon chain length. The distribution of A-S-F assumes only 50 wt.% Of the diesel fraction, while in the proposed options obtained> 65 wt.%.

Liquid hydrocarbons obtained on these catalysts are more valuable than products with a wide distribution of type A-S-F, because they can be used directly as a diesel fuel mixture without hydrocracking, which is usually carried out to increase the cetane number and reduce the sulfur content in petroleum diesel fuel. Since the proposed method uses a simple single-pass technology, it requires a relatively small capital cost.

Although this description illustrates preferred embodiments of the invention, it should be understood that the present invention is not limited to these specific options. Specialists in this field will see possible variations and modifications. For a full description of the invention and its prospects, you should refer to the essence of the invention and the attached formula, together with a description and figures.

Claims (38)

1. A method of implementing the Fischer-Tropsch process for producing liquid hydrocarbons containing mainly diesel fuel or a diesel mixture, to obtain a liquid hydrocarbon product containing less than 10 wt. % wax (> C23) and more than 65% of the diesel fraction (C9-C23), including the stages:
operations at pressures below 200 psi. inch (abs); and
the use of a cobalt catalyst comprising a Fischer-Tropsch catalyst carrier with crystallites of metal cobalt on it, and crystallites of metal cobalt have an average diameter of more than 16 nm. 2. The method of claim 1, wherein said Fischer-Tropsch catalyst carrier is selected from the group consisting of alumina, gamma alumina, zirconia, titanium oxide, silicon oxide, and mixtures thereof. 3. The method according to p. 1, in which the cobalt catalyst contains cobalt metal and the content of metallic cobalt in the cobalt catalyst is at least 15 wt.%. 4. The method according to p. 1, in which the conversion of CO in the feed gas is at least 60%. 5. The method according to any one of paragraphs. 1-4, in which a promoter is used and said promoter is selected from the group consisting of ruthenium, rhenium, rhodium, nickel, zirconium, titanium and mixtures thereof. 6. The method according to any one of paragraphs. 1-4, in which a single distillation is carried out to reduce the cracking of light hydrocarbons having a lower boiling point than the diesel fraction. 7. The method of claim 1, wherein the Fischer-Tropsch reactor is used without off-gas recycle. 8. The method according to any one of paragraphs. 1-4 or 7, in which a reforming unit with air is used as an oxygen source. 9. The method according to any one of paragraphs. 1-4 or 7, in which the Fischer-Tropsch reactor used in the specified method is a fixed-bed Fischer-Tropsch reactor or a suspended Fischer-Tropsch bubble reactor. 10. A method of implementing the Fischer-Tropsch process with operations at a pressure below 200 psi. inch (abs) using an aerial autothermal reforming unit with a CO conversion of at least 60% and a diesel yield of more than 65 wt.% in a Fischer-Tropsch single pass reactor, comprising the step of using a cobalt catalyst containing at least 15 cobalt metal wt. % and rhenium in an amount of less than 2 wt. %, said cobalt catalyst comprising a catalyst support material selected from the group consisting of alumina, zirconia, silicon oxide and mixtures thereof, and contains crystallites of metallic cobalt on it with an average diameter of more than 16 nm. 11. The method of claim 10, wherein the Fischer-Tropsch catalyst carrier is gamma alumina. 12. The method of claim 10, wherein selective membranes or molecular sieves are used to remove hydrogen from the Fischer-Tropsch feed gas. 13. The method of claim 10, wherein the operating pressure is at least 40 psi. inch (abs), and the temperature in the Fischer-Tropsch reactor is at least 190 ° C. 14. The method of claim 10, wherein the operating pressure is less than 100 psi. inch (abs). 15. The method of implementing the Fischer-Tropsch process according to claim 10, wherein said cobalt catalyst further comprises a promoter selected from the group consisting of ruthenium, rhenium and mixtures thereof. 16. A method of implementing the Fischer-Tropsch process with a CO conversion of at least 60% and a diesel fraction of more than 65 wt.% In a Fischer-Tropsch reactor, comprising the steps of:
operations at pressures below 200 psi. inch (abs);
the use of an air refinery reforming plant; and
the use of a cobalt catalyst with a metal cobalt content of at least 15 wt. % and rhenium less than 2 wt. % on a Fischer-Tropsch catalyst carrier selected from the group consisting of alumina, zirconia, silicon oxide and mixtures thereof, said cobalt catalyst being in the form of cobalt metal crystallites with an average diameter of more than 16 nm. 17. The method of claim 16, wherein the Fischer-Tropsch catalyst carrier is alumina. 18. The method of claim 16, wherein the exhaust gases of the Fischer-Tropsch reforming unit are partially recycled to the reforming unit. 19. The method of claim 16, wherein selective membranes or molecular sieves are used to remove hydrogen from the source gas fed to the Fischer-Tropsch reactor. 20. The method according to p. 16, in which the operating pressure is at least 40 psi. inch (abs), and the temperature in the Fischer-Tropsch reactor is at least 190 ° C. 21. The method according to p. 16, in which the operating pressure is not more than 100 psi. inch (abs). 22. The method of implementing the Fischer-Tropsch process according to claim 16, wherein said reactor further includes a promoter that is selected from the group consisting of ruthenium, rhenium and mixtures thereof. 23. A method of implementing the Fischer-Tropsch process in a Fischer-Tropsch reactor, comprising the steps of:
operations at pressures below 200 psi. inch (abs);
use of an oxygen steam reforming unit;
providing a CO conversion of at least 60% and a diesel fraction yield of more than 65 wt.%; and
the use of a cobalt metal catalyst with a metal cobalt content of at least 15 wt. % and rhenium less than 2 wt. % on the carrier of the Fischer-Tropsch catalyst, which is selected from the group consisting of alumina, zirconium oxide, silicon oxide and mixtures thereof, said carrier containing cobalt metal crystallites with an average diameter of more than 16 nm. 24. The method of claim 23, wherein the Fischer-Tropsch catalyst carrier is gamma alumina. 25. The method according to any one of paragraphs. 23, in which selective membranes or molecular sieves are used to remove hydrogen from the feed gas fed to the Fischer-Tropsch reactor. 26. The method according to any one of paragraphs. 23-25, in which the exhaust gas of the reforming unit is partially or completely burned to produce heat for the reforming unit. 27. The method according to any one of paragraphs. 23-25, in which the operating pressure is at least 40 psi. inch (abs) and the temperature is at least 190 ° C. 28. The method according to any one of paragraphs. 23-25, in which the operating pressure is less than 100 psi. inch (abs). 29. The method of implementing the Fischer-Tropsch process according to any one of paragraphs. 23-25, in which the specified reactor further includes a promoter that is selected from the group consisting of ruthenium, rhenium and mixtures thereof. 30. A method of implementing the Fischer-Tropsch process with a CO conversion of more than 60% and a diesel fraction yield of more than 65 wt. %, including stage:
operations at pressures below 200 psi. inch (abs), use of a reformer with incomplete oxidation by air or oxygen; and
the use of a Fischer-Tropsch reactor with a cobalt catalyst containing cobalt metal in an amount of more than 15 wt. % and rhenium in an amount of less than 2 wt. % on the carrier of the Fischer-Tropsch catalyst, which is selected from the group consisting of alumina, zirconia and silicon oxide and mixtures thereof, said cobalt catalyst being in the form of metal crystallites with an average diameter of more than 16 nm. 31. The method of claim 30, wherein the Fischer-Tropsch catalyst carrier is alumina. 32. The method according to PP. 30 or 31, in which selective membranes or molecular sieves are used to remove hydrogen from the feed gas fed to the Fischer-Tropsch reactor. 33. The method of claim 30, wherein the operating pressure is at least 40 psi. inch (abs) and a temperature of at least 190 ° C. 34. The method according to p. 30, in which the operating pressure is less than 100 psi. inch (abs). 35. The method of implementing the Fischer-Tropsch process according to claim 30, wherein said reactor further includes a promoter that is selected from the group consisting of ruthenium, rhenium and mixtures thereof. 36. The method according to any one of paragraphs. 1, 10, 16, 23 or 30, in which the temperature in the Fischer-Tropsch reactor is at least 190 ° C. 37. The method according to any one of paragraphs. 1, 10, 16, 23 or 30, in which the temperature in the Fischer-Tropsch reactor is at least 190 ° C., the operating pressure is at least 40 psi. inch (abs), wherein the method uses a promoter that is selected from the group consisting of ruthenium, rhenium, rhodium, nickel, zirconium, titanium, and mixtures thereof; and in which the conversion of CO exceeds 65%. 38. The method according to p. 37, in which the conversion of CO exceeds 65%.

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