Method for passivating a Fischer-Tropsch catalyst
The method addresses solvent use and exothermic risks in Fischer-Tropsch catalyst passivation by controlling gas temperature and oxygen content, ensuring safe and efficient catalyst discharge.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2024-04-25
- Publication Date
- 2026-03-19
AI Technical Summary
Existing methods for passivating Fischer-Tropsch catalysts involve the use of solvents, leading to environmental impact and potential exothermic oxidation risks due to incomplete hydrocarbon removal and oxygen contact.
A method involving controlled temperature and oxygen content adjustment of an inert gas flow through a Fischer-Tropsch reactor to strip and oxidize hydrocarbons on the catalyst surface without solvents, ensuring safe catalyst discharge.
This method effectively removes hydrocarbons from the catalyst surface, preventing dangerous oxidation and fire hazards while being environmentally friendly and cost-effective.
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Figure 2026509465000001_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a method for deactivating a Fischer-Tropsch catalyst.
Background Art
[0002] One well-known process for producing hydrocarbons on an industrial scale is the Fischer-Tropsch process, in which a mixture of carbon monoxide and hydrogen is reacted in a reactor in the presence of a catalyst to produce a reaction product containing hydrocarbons.
[0003] These reactions occur in the presence of a metal catalyst, typically at a temperature of 150 to 300 °C and a pressure of 1 to several tens of atmospheres. The Fischer-Tropsch process ideally involves a series of chemical reactions that produce various hydrocarbons having the formula (C n H 2n+2 ). A more useful reaction is to produce alkanes as follows: (2n + 1)H2 + nCO → C n H 2n+2 + nH2O <了 The formation of methane (n = 1) is undesirable. Most of the useful alkanes produced tend to be straight-chain liquids suitable as fuels. In addition to alkane formation, competing reactions result in small amounts of alkenes, as well as alcohols and other oxygenated hydrocarbons. The Fischer-Tropsch reaction is a highly exothermic reaction because the standard reaction enthalpy (ΔH) is -165 kJ / mol of CO in total.
[0004] WO 2012 / 146903 discloses a process for converting syngas to higher hydrocarbons by contacting a gas stream containing syngas with a particulate Fischer-Tropsch catalyst, the process being carried out in a tubular reactor, the reactor comprising one or more tubes in which one or more supports for the particulate catalyst are disposed.
[0005] After the Fischer-Tropsch reaction, at some point the catalyst needs to be removed from the reactor for regeneration or reprocessing. However, this can be a safety issue because catalysts are usually coated with hydrocarbons such as wax, which are susceptible to exothermic oxidation in air, posing a potential fire hazard. Therefore, the hydrocarbons must be removed from the catalyst before it can be removed from the reactor, and the catalyst must be at least partially oxidized to passivate the reactive metal components of the Fischer-Tropsch catalyst.
[0006] Methods for in-situ passivation of Fischer-Tropsch catalysts are described in International Publication No. 2012085227(A1), International Publication No. 2010069978(A1), U.S. Patent No. 9556570(B2), and German Patent No. 2222531(A). Such methods require the use of a solvent to remove hydrocarbons from the catalyst and then contacting the catalyst with a stream of oxygen at high temperatures. The use of a solvent increases the environmental impact of the method and results in a waste stream that requires treatment or disposal. Furthermore, unless substantially all hydrocarbons are removed from the catalyst, contacting the catalyst with a stream of oxygen can result in exothermic oxidation, which can raise the catalyst temperature to dangerously high levels.
[0007] The present invention aims to address at least some of the problems related to the prior art, or to provide at least a commercially acceptable alternative solution. [Overview of the project]
[0008] One aspect of this disclosure relates to a method for passivating a Fischer-Tropsch catalyst in a catalyst support placed in a Fischer-Tropsch reactor, the method being: The present invention provides a Fischer-Tropsch catalyst in a catalyst support arranged within a Fischer-Tropsch reactor, wherein the Fischer-Tropsch reactor has an inlet and an outlet, the catalyst support is positioned between the inlet and the outlet, and the Fischer-Tropsch catalyst has hydrocarbons on its surface. The Fischer-Tropsch catalyst is brought into contact with the gas by passing a gas flow through an inlet, through a catalyst support, and then out through an outlet, wherein the gas passed through the inlet has a first oxygen content. While maintaining the gas flow, The temperature of the Fischer-Tropsch catalyst is adjusted to a first temperature of 100-280°C to strip hydrocarbons from the surface of the Fischer-Tropsch catalyst, The stripped hydrocarbons are removed from the catalyst support and the Fischer-Tropsch reactor, Adjusting the temperature of the Fischer-Tropsch catalyst to a second temperature of 100-180°C, To increase the oxygen content of the gas passed through the inlet to the second oxygen content, Cooling the catalyst support to below 40°C, This includes increasing the oxygen content of the gas passed through the inlet to a third oxygen content, Here, The gas passed through the inlet having the first oxygen content is an inert gas. The first oxygen content is less than 0.1 mol% oxygen. The second oxygen content is 0.1 to 15 mol% oxygen, and The third oxygen content is greater than 15 mol% oxygen. [Brief explanation of the drawing]
[0009] [Figure 1] This is a diagram of one embodiment of a system to which the method of the present invention can be applied. [Figure 2] This chart shows the passivation of a cobalt-containing catalyst in a support, indicating the mole percentages of oxygen and carbon dioxide, as well as the catalyst temperature during the passivation process. [Modes for carrying out the invention]
[0010] This disclosure relates to a method for passivating a Fischer-Tropsch catalyst in a catalyst support placed in a Fischer-Tropsch reactor, the method being: The present invention provides a Fischer-Tropsch catalyst in a catalyst support arranged within a Fischer-Tropsch reactor, wherein the Fischer-Tropsch reactor has an inlet and an outlet, the catalyst support is positioned between the inlet and the outlet, and the Fischer-Tropsch catalyst has hydrocarbons on its surface. The Fischer-Tropsch catalyst is brought into contact with the gas by passing a gas flow through an inlet, through a catalyst support, and then out through an outlet, wherein the gas passed through the inlet has a first oxygen content. While maintaining the gas flow, The temperature of the Fischer-Tropsch catalyst is adjusted to a first temperature of 100-280°C to strip hydrocarbons from the surface of the Fischer-Tropsch catalyst, The stripped hydrocarbons are removed from the catalyst support and the Fischer-Tropsch reactor, Adjusting the temperature of the Fischer-Tropsch catalyst to a second temperature of 100-180°C, To increase the oxygen content of the gas passed through the inlet to the second oxygen content, Cooling the catalyst support to below 40°C, This includes increasing the oxygen content of the gas passed through the inlet to a third oxygen content, Here, The gas passed through the inlet having the first oxygen content is an inert gas. The first oxygen content is less than 0.1 mol% oxygen. The second oxygen content is 0.1 to 15 mol% oxygen, and The third oxygen content is greater than 15 mol% oxygen.
[0011] Each aspect or embodiment defined herein may be combined with any other aspect or embodiment unless expressly indicated otherwise. Specifically, any feature indicated as preferred or advantageous may be combined with any other feature indicated as preferred or advantageous.
[0012] Advantageously, in contrast to conventional methods, the method of the present invention can remove hydrocarbons from the catalyst without using a solvent. The Applicant has found that it is not necessary to wash the hydrocarbons from the pores of the catalyst in order to achieve satisfactory catalyst deactivation prior to discharge from the Fischer-Tropsch reactor. Thus, in contrast to conventional methods, the method of the present invention can be more environmentally friendly and / or less costly and may not require the treatment and / or disposal of solvent waste streams.
[0013] Surprisingly, although hydrocarbons may remain within the pores of the catalyst, by using an inert gas to strip the hydrocarbons from the catalyst surface, the stripped catalyst can become free-flowing. This can make it easier to remove the stripped catalyst from the catalyst support.
[0014] This method involves deactivating a Fischer-Tropsch catalyst. Fischer-Tropsch catalysts are known in the art. The Fischer-Tropsch catalyst can be in the form of catalyst particles. The Fischer-Tropsch catalyst can include a catalytically active metal and optionally a promoter supported on a catalyst support material. The catalyst support material can include a metal oxide, preferably a porous metal oxide.
[0015] In the present invention, the Fischer-Tropsch catalyst is provided within a catalyst support. Suitable catalyst supports are known in the art. The catalyst support can be in the form of a container, for example, as described in International Publication No. WO 2012 / 146903 or International Publication No. WO 2016 / 050520. The catalyst support can be formed from, for example, steel, preferably stainless steel.
[0016] The catalyst support is disposed within a Fischer-Tropsch reactor. Fischer-Tropsch reactors are known in the art. The Fischer-Tropsch reactor has an inlet and an outlet, and the catalyst support is disposed between the inlet and the outlet. By being disposed within the catalyst support, the catalyst is in fluid communication with both the inlet and the outlet.
[0017] Hydrocarbons on the surface of a Fischer-Tropsch catalyst are typically solid or liquid at room temperature and pressure. These hydrocarbons typically include waxes. Such hydrocarbons are typically produced during the Fischer-Tropsch reaction.
[0018] This method involves bringing a Fischer-Tropsch catalyst into contact with a gas by passing a gas flow through an inlet, through a catalyst support, and then out through an outlet. As understood, the catalyst support has an inlet and an outlet for allowing the gas to pass through it.
[0019] The gas introduced into the inlet has a first oxygen content. Preferably, the first oxygen content of the gas is maintained until the oxygen content increases to a second oxygen content.
[0020] This method includes steps in which the gas flow is maintained. "Maintained" means that the gas continues to flow during these steps. The flow rate is preferably substantially constant during such "maintenance," but it does not need to be constant.
[0021] This method involves adjusting the temperature of the Fischer-Tropsch catalyst to a first temperature of 100-280°C, which is sufficient for the gas flow to strip hydrocarbons from the surface of the Fischer-Tropsch catalyst. Lower temperatures may be insufficient to melt hydrocarbons, such as wax, which means that undesirable high levels of wax remain on the catalyst. Higher temperatures are unnecessary and may cause the wax to volatilize, which means that it is more difficult to remove from the Fischer-Tropsch reactor using conventional methods such as the use of a gas-liquid separator.
[0022] This method involves removing the stripped hydrocarbons from the catalyst support and the Fischer-Tropsch reactor. This can avoid oxidation of the stripped hydrocarbons as the oxygen content of the gas subsequently increases. This can reduce the risk of fire and / or the risk of the catalyst temperature reaching dangerously high levels. The stripped hydrocarbons can then be discarded or subjected to separation and / or purification processes.
[0023] This method involves adjusting the temperature of the Fischer-Tropsch catalyst to a second temperature of 100-180°C, and then increasing the oxygen content of the gas passed through the inlet to a second oxygen content. Temperature adjustment preferably involves cooling the Fischer-Tropsch catalyst to the second temperature. This increase in oxygen content to a second oxygen content can result in controlled oxidation of the reactive components of the catalyst and any hydrocarbons remaining on the catalyst. Thus, the catalyst can then be safely discharged from the catalyst support and / or Fischer-Tropsch reactor. If the temperature is too low, passivation may be insufficient. If the temperature is too high, it may result in undesirable high levels of oxidation, which can raise the temperature of the catalyst and / or catalyst support to dangerously high levels. The second temperature is preferably lower than the first temperature.
[0024] This method further includes cooling the catalyst support to below 40°C, for example, to room temperature. This may allow for the safe removal of the catalyst and / or catalyst support from the Fischer-Tropsch reactor.
[0025] This method further includes increasing the oxygen content of the gas introduced into the inlet to a third oxygen content. The higher the oxygen content, the greater the level of catalyst passivation, thereby preventing dangerously high levels of oxidation of the catalyst during or after discharge from the Fischer-Tropsch reactor.
[0026] The gas passed through the inlet having the first oxygen content is an inert gas. This can avoid significant oxidation of the catalyst and / or combustion of hydrocarbons at the first temperature. The term “inert gas” has its usual meaning in the art and may include gases that are substantially free of oxygen or oxidizing gases, for example, gases with less than 0.1 mol% oxygen or oxidizing gases. The gas may be inert to such an extent that it does not result in a significant level of oxidation of the catalyst and / or combustion of hydrocarbons at the first temperature. Suitable inert gases are known to those skilled in the art and include nitrogen and argon.
[0027] The first oxygen content is less than 0.1 mol% oxygen. If the oxygen content is high, oxidation of the catalyst and / or combustion of hydrocarbons may reach a significant level at the first temperature.
[0028] The second oxygen content is 0.1 to 15 mol% oxygen. If the oxygen content is too low, the level of catalyst passivation at the second temperature may be minimal. If the oxygen content is too high, oxidation may be severe, which is undesirable.
[0029] The third oxygen content is greater than 15 mol% oxygen.
[0030] Preferably, this method further includes measuring the oxygen content of the gas passed through the inlet and the gas discharged from the outlet, and increasing the oxygen content of the gas passed through the inlet to a second oxygen content is done in increments of 2 mol% or less, and the second and subsequent increments are postponed until the oxygen content of the gas passed through the inlet is substantially equal to the oxygen content of the gas discharged from the outlet. This results in controlled oxidation or passivation of the catalyst and can prevent the catalyst temperature from rising to dangerously high levels.
[0031] The first increment preferably increases the oxygen content to 0.1–0.4 mol%, more preferably 0.2–0.3 mol%. This results in controlled oxidation of the catalyst and can prevent the catalyst temperature from rising to dangerously high levels.
[0032] Increasing the oxygen content of the gas introduced into the inlet to the second oxygen content is done in increments of 0.2–0.8 mol% oxygen, preferably 0.4–0.6 mol%, up to an intermediate oxygen content of 4–6 mol%, and then in increments of 0.7–1.7 mol% oxygen, preferably 0.9–1.1 mol%, from the intermediate oxygen content to the second oxygen content. This results in controlled oxidation of the catalyst and can avoid the catalyst temperature rising to dangerously high levels. Larger increments with higher oxygen content can accelerate the process without risking dangerously high catalyst temperatures.
[0033] The Fischer-Tropsch catalyst preferably contains cobalt. This method may be particularly suitable for passivating a cobalt-containing Fischer-Tropsch catalyst.
[0034] This method is preferably carried out at a pressure of 2 to 10 barg. Lower pressures may result in insufficient oxidation or passivation of the catalyst and / or insufficient stripping of hydrocarbons from the catalyst. Higher pressures may be economically undesirable and / or may result in an undesirablely high rate of catalyst oxidation.
[0035] This method preferably involves 500 to 3000 hours. -1 The process is carried out at a gas space-time velocity. A low gas space-time velocity may result in insufficient oxidation or passivation of the catalyst, and / or insufficient stripping of hydrocarbons from the catalyst. Higher gas space-time velocities may be economically undesirable.
[0036] Preferably, the inert gas contains nitrogen, and / or the inert gas consists essentially of nitrogen. Nitrogen is sufficiently inert to avoid substantial oxidation of the catalyst and / or combustion of hydrocarbons at the first temperature. Furthermore, nitrogen is low-cost, widely available, and easy to handle.
[0037] The hydrocarbons preferably include wax. This method may be particularly suitable for stripping wax from Fischer-Tropsch catalysts.
[0038] When the hydrocarbon contains wax, removing the stripped hydrocarbon from the catalyst support and the Fischer-Tropsch reactor preferably involves using a first gas-liquid separator downstream of the Fischer-Tropsch reactor. The gas-liquid separator may be particularly effective in separating the wax from the gas supplied to the Fischer-Tropsch reactor. Gas-liquid separators are known in the art.
[0039] The method preferably further includes maintaining a first temperature until substantially no more wax is collected in the first gas-liquid separator, more preferably until no more wax is collected in the first gas-liquid separator. This may result in a catalyst having only very low levels of wax, and the catalyst surface may be substantially free of or contain no wax before the catalyst is subjected to a second temperature. This may avoid significant combustion of wax when the catalyst is subjected to a second temperature and a second oxygen content.
[0040] The first oxygen content is preferably 0.01 mol% or less of oxygen. Such an oxygen content may be particularly suitable for avoiding significant levels of oxidation of the catalyst and / or combustion of hydrocarbons at the first temperature.
[0041] The first temperature is preferably 150°C to 250°C. Such a temperature is particularly suitable for melting the wax while avoiding its volatilization.
[0042] The second temperature is preferably 110°C to 130°C. This can result in particularly controlled oxidation or passivation of the catalyst.
[0043] The second oxygen content is preferably 8 to 12 mol% oxygen. This can result in particularly controlled oxidation or passivation of the catalyst.
[0044] Preferably, the method further includes increasing the oxygen content of the gas passed through the inlet to a second oxygen content, and then maintaining the second temperature for at least 2 hours, preferably until no further exothermic oxidation is observed, before cooling the catalyst support to below 40°C. This ensures that a desirable high level of oxidation or passivation of the catalyst is achieved.
[0045] The third oxygen content is preferably 20-22 mol% oxygen. Such an oxygen content is similar to that of air. This ensures that substantially no further oxidation of the catalyst occurs during or after the catalyst is discharged.
[0046] The gas is preferably recirculated from the outlet to the inlet. This can reduce the amount of gas required by the method, thereby lowering costs and avoiding the need to dispose of large quantities of gas.
[0047] Providing a Fischer-Tropsch catalyst in a catalyst support preferably involves cooling the Fischer-Tropsch catalyst from its operating temperature to a first temperature. In a typical Fischer-Tropsch process, the operating temperature of the catalyst is typically higher than the first temperature.
[0048] Increasing the oxygen content of a gas preferably involves introducing air into the inert gas. The air contains an appropriate amount of oxygen, and the remaining components are sufficiently inert. Using air is less costly than using other oxygen-containing gases such as pure oxygen.
[0049] The Fischer-Tropsch catalyst surface is preferably substantially free of hydrocarbons (more preferably hydrocarbon-free) before adjusting the temperature of the Fischer-Tropsch catalyst to a second temperature. This helps to avoid combustion of hydrocarbons at the second temperature, which could raise the catalyst temperature to dangerously high levels.
[0050] In a further embodiment, the present invention provides a Fischer-Tropsch catalyst passed through a method described herein. Such a catalyst can advantageously exhibit a high level of passivation and / or be particularly free-flowing. [Examples]
[0051] Referring to Figure 1, a diagram of one embodiment of a system to which the method of the present invention can be applied is shown.
[0052] Those skilled in the art will understand that the drawings are schematic and that commercial plants may require additional equipment such as raw material drums, pumps, vacuum pumps, compressors, gas recirculation compressors, temperature sensors, pressure sensors, pressure relief valves, control valves, flow controllers, level controllers, holding tanks, and storage tanks. The provision of such ancillary equipment does not form part of the present invention and follows conventional chemical engineering practices.
[0053] In Figure 1, a synthesis gas production unit 10 produces a refined synthesis gas mixture consisting essentially of hydrogen and carbon monoxide under high temperature and pressure. The synthesis gas is supplied from the synthesis gas production unit 10 via line 12 and combined with a recirculation flow in line 14 to produce a reaction gas mixture. This reaction gas mixture is supplied via line 16 to a Fischer-Tropsch reactor 18, which contains multiple catalyst supports including a cobalt Fischer-Tropsch catalyst in a reaction tube 20. Tube 20 is cooled by pressurized boiling water supplied to the reactor via line 22, which is supplied by a steam drum 24. Steam is recovered from the Fischer-Tropsch reactor 18 via line 26 and returned to the steam drum 24. The steam drum is supplied with a flow of boiler feedwater (not shown), and steam is recovered from the steam drum via line 28. An auxiliary steam supply line 30 is provided in line 22. Hydrocarbons are compounds resulting from the reaction of hydrogen and carbon monoxide on the Fischer-Tropsch catalyst. The product mixture is recovered from the Fischer-Tropsch reactor 18 via line 32 and fed to a first gas-liquid separator 34, where the liquid wax product is separated from the product gas and unreacted gas and recovered via line 36 for optional further processing. The gaseous product and unreacted gas are fed from the first gas-liquid separator 34 via line 38 to one or more heat exchangers 40, where they are cooled to condense a mixture of co-produced water and condensable hydrocarbon products. The cooled mixture formed in one or more heat exchangers 40 is fed via line 42 to a second gas-liquid separator 44, where the condensed water and hydrocarbons are separated and recovered via line 46 for further processing. The unreacted gas mixture, including hydrogen, carbon monoxide, and optionally carbon dioxide, and / or non-condensable hydrocarbons, is recovered from the second gas-liquid separator 44 via line 48 and compressed in a circulating compressor 50 to form a recirculating gas flow 14. The purge line 52 is drawn from the unreacted gas mixture line 48 upstream of the compressor 48.
[0054] To operate the passivation process, the synthesis gas feed in line 12 is shut off using valve 54, and the Fischer-Tropsch reaction is quiesced in the reaction tube 20. An inert gas, such as nitrogen gas, is supplied to line 48 upstream of the circulating compressor 50 via line 56 by opening valve 58. The inert gas may be preheated. The temperature of the Fischer-Tropsch catalyst in the catalyst support can be controlled using auxiliary steam supplied to reactor 18 via line 30. The inert gas is preferably circulated through the reactor until the flow of hydrocarbon wax to the first gas-liquid separator 34 is stopped and recovered via line 36.
[0055] At this point, a flow of dry air, preferably plant air or instrument air, is supplied to line 48 via line 60 upstream of the inert gas supply line 56 by opening valve 62. The relative flow rates of the inert gas in line 56 and the air in line 60 are controlled to provide an initial O2 concentration of 0.25%. The heat generated by oxidation in the reactor caused by the addition of O2 is monitored by thermocouples (not shown), and the vapor flow via line 30 is adjusted as needed to maintain the temperature during oxidation. The amount of air is gradually increased by adjusting valves 58 and 62.
[0056] Once no further heat generation is observed, increase the air circulation and stop the inert gas flow by closing valve 58.
[0057] The passivated catalyst in the support can then be recovered from the reaction tube 20.
[0058] An example of the passivation method carried out using the process shown in Figure 1 was performed by cooling the catalyst in the catalyst support from the Fischer-Tropsch reaction temperature to 120°C while purging the synthesis gas from the reactor loop with nitrogen gas. The reactor pressure was reduced to 10 barg and the circulator was operated to deliver the maximum gas flow at the operating pressure. The temperature of the Fischer-Tropsch reactor was raised to 180°C at a rate of 10°C / h and held for 6 hours. The Fischer-Tropsch reactor was cooled to obtain an average catalyst temperature of 120°C. Air was introduced from the air supply to increase the oxygen content at the Fischer-Tropsch reactor inlet to 0.5 mol%. The introduction of low concentrations of air limits the oxidant content in the loop and allows for good temperature control when the cobalt in the catalyst is oxidized. The operating temperature of 120°C increases the reaction rate of oxidation but is low enough to minimize combustion of organic matter. The temperature was monitored to ensure that there was no undesirable rise in catalyst temperature indicating combustion of organic matter. Carbon dioxide and oxygen levels were measured at the reactor inlet and outlet to confirm the absence of combustion. The oxygen content was gradually increased in 0.5 mol% increments toward 10 mol% in the Fischer-Tropsch reactor and held for 4 hours. Passivation at 120°C and a final oxygen concentration of 10 mol% ensures sufficient oxidation of cobalt to guarantee no thermal runaway at ambient temperature when exposed to air.
[0059] This procedure ensures that the catalyst in the carrier is handled safely when discharged from the reactor and that the catalyst flows freely when discharged from the carrier.
[0060] Figure 2 shows the catalyst temperature, carbon dioxide, and oxygen concentrations at the inlet to the Fischer-Tropsch reactor as passivation progresses. This chart shows that temperature control within the safety limits by the method of the present invention was achieved without hydrocarbon combustion, as indicated by the low carbon dioxide levels observed.
[0061] The detailed description above is provided for illustrative and illustrative purposes only and is not intended to limit the scope of the appended claims. Many modifications of the currently preferred embodiments shown herein will be obvious to those skilled in the art and remain within the scope of the appended claims and their equivalents.
Claims
1. A method for passivating a Fischer-Tropsch catalyst in a catalyst support placed in a Fischer-Tropsch reactor, wherein the method is: The present invention provides a Fischer-Tropsch catalyst in a catalyst support arranged within a Fischer-Tropsch reactor, wherein the Fischer-Tropsch reactor has an inlet and an outlet, the catalyst support is positioned between the inlet and the outlet, and the Fischer-Tropsch catalyst has hydrocarbons on its surface. The Fischer-Tropsch catalyst is brought into contact with the gas by passing a gas flow through the inlet, through the catalyst support, and then out through the outlet, wherein the gas passed through the inlet has a first oxygen content. While maintaining the aforementioned gas flow The temperature of the Fischer-Tropsch catalyst is adjusted to a first temperature of 100 to 280°C to strip hydrocarbons from the surface of the Fischer-Tropsch catalyst, The stripped hydrocarbons are removed from the catalyst support and the Fischer-Tropsch reactor, The temperature of the Fischer-Tropsch catalyst is adjusted to a second temperature of 100 to 180°C, To increase the oxygen content of the gas passed through the inlet to a second oxygen content, The catalyst support is cooled to below 40°C, This includes increasing the oxygen content of the gas passed through the inlet to a third oxygen content, Here, The gas passed through the inlet having the first oxygen content is an inert gas. The first oxygen content is less than 0.1 mol% oxygen, The second oxygen content is 0.1 to 15 mol% oxygen, and The third method wherein the oxygen content is greater than 15 mol% of oxygen.
2. The method according to claim 1, further comprising measuring the oxygen content of the gas passed through the inlet and the oxygen content of the gas discharged from the outlet, wherein the oxygen content of the gas passed through the inlet is increased to the second oxygen content in increments of 2 mol% or less, and the second and subsequent increments are postponed until the oxygen content of the gas passed through the inlet is substantially equal to the oxygen content of the gas discharged from the outlet.
3. The method according to claim 2, wherein the first increment increases the oxygen content to an oxygen content of 0.1 to 0.4 mol%, preferably 0.2 to 0.3 mol%, of oxygen.
4. Increasing the oxygen content of the gas passed through the inlet to the second oxygen content means Up to an intermediate oxygen content of 4-6 mol%, the process is carried out in increments of 0.2-0.8 mol% oxygen, preferably 0.4-0.6 mol% oxygen. The method according to claim 2 or claim 3, wherein the reduction from the intermediate oxygen content to the second oxygen content is carried out in increments of 0.7 to 1.7 mol% oxygen, preferably 0.9 to 1.1 mol% oxygen.
5. The method according to any one of claims 1 to 4, wherein the Fischer-Tropsch catalyst comprises cobalt.
6. The method according to any one of claims 1 to 5, wherein the method is performed at a pressure of 2 to 10 barg.
7. The above method is 500 to 3000 h －１ The method according to any one of claims 1 to 6, performed at the gas spacetime velocity.
8. The method according to any one of claims 1 to 7, wherein the inert gas comprises nitrogen and / or the inert gas is essentially nitrogen.
9. The method according to any one of claims 1 to 8, wherein the hydrocarbon includes wax.
10. The method according to claim 9, wherein removing the stripped hydrocarbons from the catalyst support and the Fischer-Tropsch reactor includes using a first gas-liquid separator downstream of the Fischer-Tropsch reactor.
11. The method according to claim 10, further comprising maintaining the first temperature until substantially no wax is collected in the first gas-liquid separator.
12. The method according to any one of claims 1 to 11, wherein the first oxygen content is 0.01 mol% or less of oxygen.
13. The method according to any one of claims 1 to 12, wherein the first temperature is 150°C to 250°C.
14. The method according to any one of claims 1 to 13, wherein the second temperature is 110°C to 130°C.
15. The method according to any one of claims 1 to 14, wherein the second oxygen content is 8 to 12 mol% oxygen.
16. The method according to any one of claims 1 to 15, further comprising increasing the oxygen content of the gas passed through the inlet to a second oxygen content, and then maintaining the second temperature for at least two hours, preferably until no further oxidative heat is observed, before cooling the catalyst support to below 40°C.
17. The method according to any one of claims 1 to 16, wherein the third oxygen content is 20 to 22 mol% oxygen.
18. The method according to any one of claims 1 to 17, wherein the gas is recirculated from the outlet to the inlet.
19. The method according to any one of claims 1 to 18, wherein providing a Fischer-Tropsch catalyst in a catalyst support comprises cooling the Fischer-Tropsch catalyst from an operating temperature to a first temperature.
20. The method according to any one of claims 1 to 19, wherein increasing the oxygen content of the gas includes introducing air into the inert gas.
21. The method according to any one of claims 1 to 20, wherein the Fischer-Tropsch catalyst is substantially free of hydrocarbons before adjusting the temperature of the Fischer-Tropsch catalyst to the second temperature.
22. A Fischer-Tropsch catalyst passed through according to the method described in any one of claims 1 to 21.