Fischer-Tropsch Catalyst Activation

Abstract

The present disclosure relates generally to methods for activating a Fischer-Tropsch synthesis catalyst. In particular, the present application relates to a method for activating a Fischer-Tropsch synthesis catalyst, the method comprising: (i) contacting the catalyst with a first gaseous composition comprising at least 80% N2 at a pressure in the range of 2 barg to 20 barg and a temperature of 150°C or less; (ii) contacting the catalyst with a second gaseous composition comprising at least 80% H2 to form a H2 / N2 gaseous composition having a H2:N2 molar ratio in the range of 0.2:1 to 2:1, resulting in a pressure in the range of 10 barg to 30 barg. (iii) increasing the temperature to a range of 220° C. to 260° C.; and (iv) maintaining the catalyst under the conditions of step (iii) for a holding period in the range of 2 hours to 96 hours.

Description

[Technical field]

[0001] The present disclosure relates to the Fischer-Tropsch process, and in particular to techniques for activating Fischer-Tropsch catalysts, and uses thereof. [Background technology]

[0002] The conversion of synthesis gas to hydrocarbons via the Fischer-Tropsch process has been known for decades, but historically has lagged in performance compared to other hydrocarbon synthesis techniques. As alternative energy sources grow in importance, there has been a resurgence of interest in the Fischer-Tropsch (FT) process, as it enables a direct and environmentally acceptable route to high quality fuels and feedstock chemicals.

[0003] The FT process is known to produce linear hydrocarbons for use in fuels, as well as oxygenates that serve as valuable feedstock chemicals. Hydrocarbon fuels derived from the FT process can better meet increasingly stringent environmental regulations compared to fuels produced in conventional refineries, since FT-derived fuels typically have lower sulfur, nitrogen, and aromatics content that contribute to the emission of powerful pollutants such as SO2, NOx, and particulates. Alcohols derived from the FT process often have higher octane numbers than hydrocarbons and therefore burn more completely, thereby reducing the environmental impact of such fuels. The resulting alcohols and other oxygenates can also be used as reagents in other processes, such as the synthesis of lubricants.

[0004] Various transition metals have been identified as catalytically active in the conversion of synthesis gas to hydrocarbons and their oxygenated derivatives. In particular, cobalt, nickel, and iron have been investigated, often in combination with support materials, the most common of which are alumina, silica, and carbon.

[0005] In a typical preparation of a supported cobalt-containing FT synthesis catalyst, a solid support material is contacted with a solution of a soluble cobalt compound, such as cobalt nitrate. The impregnated support is then calcined and / or oxidized to form cobalt oxides, typically one or more of CoO, Co2O3, or Co3O4. However, such oxides typically have low FT catalytic activity and must be reduced to form the preferred catalytically active species of cobalt metal.

[0006] Efficient catalyst reduction and activation is an ongoing challenge. In large-scale reactors, competing factors such as temperature, pressure, GHSV (gas space velocity), and activation gas composition must be balanced according to system tolerances, equipment design limitations, and energy considerations. Therefore, there is a need to develop improved protocols for the activation of Fischer-Tropsch catalysts. Summary of the Invention [Problem to be solved by the invention]

[0007] The present inventors have developed a method for activating Fischer-Tropsch synthesis catalysts with increased energy and material efficiency.

[0008] Thus, in one aspect, the present disclosure provides a process for activation of a Fischer-Tropsch synthesis catalyst, the process comprising: (i) contacting the catalyst with a first gaseous composition comprising at least 80% N2 at a pressure in the range of 2 barg to 20 barg and at a temperature up to 250°C; (ii) introducing a second gas composition into the first gas composition at less than 175°C, the second gas composition comprising at least 80% H, forming a H2 / N2 gas composition having a H2:N2 molar ratio in the range of 0.2:1 to 2:1, and providing a pressure in the range of 10 barg to 30 barg; (iii) increasing the temperature to a range of 220°C to 260°C at a heating rate of 20°C / hr or less and a GHSV in the range of 2000 hr-1 to 8000 hr-1. (iv) maintaining the catalyst under the conditions of step (iii) for a holding period ranging from 2 hours to 96 hours. (v) cooling the catalyst to a temperature of 150° C. or less;

[0009] In another aspect, the disclosure provides a process as otherwise described herein, the process further comprising monitoring the water concentration of the H2 / N2 gas composition during steps (ii)-(v).

[0010] Other aspects of the present disclosure will be apparent to those of skill in the art in view of the following description. [Brief description of the drawings]

[0011] [Figure 1] FIG. 1 is a schematic diagram of a reactor suitable for use in the processes described herein. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] The present disclosure relates to a method for activating a Fischer-Tropsch catalyst. Typical activation known in the art involves high temperatures in excess of 300°C and the use of pure hydrogen gas. However, the inventors have found that such simple activation protocols are not well suited for large scale reactors utilizing large amounts of catalyst and reducing gas. At large scale, pressures in excess of 10 barg and up to 5000 Nm 3 / m 3 Compressors capable of handling pressures in excess of 1.5 kPa are utilized. In absolute terms, a typical reactor or 1000 reactor tubes would require 20 m 3Catalysts in excess of 10 ... Furthermore, catalytic reduction often generates large amounts of water, which must be economically removed to avoid premature catalyst deactivation.

[0013] The inventors have surprisingly found that high performance preparations of Fischer-Tropsch catalysts can only be found by satisfying a balance between activation pressure, temperature, H2%, and GHSV. On an industrial scale, the gas is introduced by use of a high capacity compressor. In certain embodiments described elsewhere herein, the compressor has a pressure of at least 5000 Nm 3 / m 31.hr volume. Use of such compressors poses significant design challenges not found in smaller scale studies. For example, we have found that there is a tension between GHSV and %H2: a high GHSV is needed to remove the excess water that is produced as a reduction by-product. However, it is very difficult and inefficient to operate industrial compressors at high GHSV with low density gases like H2. GHSV is difficult to achieve primarily due to the low pressure required for activation, but also the effect of low molecular weight H2 gas lowering the generated head of the machine, and therefore the flow rate must also be reduced to keep the machine head in balance with the loop pressure drop.

[0014] In addition, using very high H2 content adds design complexity and cost to the compressor, both from metallurgical issues with high impeller tip speeds leading to high temperatures, and other issues related to designing equipment for high hydrogen content, such as seal systems. However, a certain amount of H2 is required to act as a reactant for the reduction reaction. Therefore, it is desirable to provide a mixture of N2 and H2, as described elsewhere herein.

[0015] As another example, high GHSV using industrial compressors is only possible by utilizing high pressure. High pressure is also favorable for driving the reduction reaction through increased H2 partial pressure. However, high operating pressures result in ineffective water removal, as the inventors have found that high operating pressures result in water being trapped within the catalyst pores. Thus, the pressure ranges described herein reflect the critical ranges that balance these competing factors.

[0016] As a further example, temperature must also be carefully controlled. Higher temperatures favor more complete reduction and also favor water removal. However, above a certain temperature (e.g., in some embodiments, above 260°C), reactor metallurgy can become unstable and susceptible to damage. Thus, maintaining low temperatures advantageously avoids capital expenditures associated with building reactors that can withstand extreme temperatures. Mechanical limitations are due to the desirability of generating reduced pressure using steam sparging of the shell. For example, a reduction temperature of 250°C corresponds to just below the manageable 40 bara saturation pressure for the steam drum associated with the FT converter. Higher temperatures require higher steam pressure and higher pressure ratings for the shell, but also thicker tubes to withstand the additional external pressure, resulting in increased capex.

[0017] Thus, in one aspect, the present disclosure provides a method for activation of a Fischer-Tropsch synthesis catalyst, the method comprising: (i) contacting the catalyst with a first gaseous composition comprising at least 80% N2 at a pressure in the range of 2 barg to 20 barg and at a temperature up to 250°C; (ii) contacting the catalyst with a second gaseous composition comprising at least 80% H to form a H2 / N2 gaseous composition having a H2:N2 molar ratio in the range of 0.2:1 to 2:1 and providing a pressure in the range of 10 barg to 30 barg; (iii) increasing the temperature to a range of 230°C to 260°C at a heating rate of 20°C / hr or less and a GHSV in the range of 2000 hr-1 to 8000 hr-1. (iv) maintaining the catalyst at the conditions of step (iii) for a holding period ranging from 3 hours to 72 hours. (v) cooling the catalyst to a temperature of 150° C. or less;

[0018] In another aspect, the disclosure provides a process as otherwise described herein, wherein step (i) either comprises a stand-alone catalyst drying step prior to step (i) or includes a drying step together with step (i) as part of the first gaseous composition treatment.

[0019] As described in more detail below, various reaction systems can be used in carrying out the processes described herein, and those skilled in the art will adapt conventional systems as necessary. As known to those skilled in the art, suitable means for controlling reactor temperature during activation and start-up can be used, including electrical heating, direct heating of the reactor tubes with steam, or indirect heating with steam via an eductor or jet pump arrangement to heat a circulating water circuit around the reactor tubes. An example of a reaction system for use in carrying out the process of the present disclosure is shown in the schematic diagram of FIG. 1. The reactor 110 is charged with catalyst 120. Gas (e.g., the first or second gaseous composition, or a combination thereof) is introduced through inlet 101 and optionally flows in a once-through configuration, exiting the system at 104. Unreacted gas is optionally removed through recycle outlet 102 and is optionally recycled back to inlet 101 through recycle feed 103 and moisture removal dryer 130.

[0020] The processes described elsewhere herein can be operated in a Fischer-Tropsch reactor to perform the activation in situ, or one skilled in the art may choose to activate the catalyst in a dedicated reactor and then transfer the activated catalyst, desirably under inert conditions, to a Fischer-Tropsch reactor for carrying out the Fischer-Tropsch synthesis.

[0021] As mentioned above, the process described elsewhere herein, in certain embodiments, includes contacting the catalyst with mostly N2 gas at relatively low temperatures and pressures. Surprisingly, the inventors have discovered that the initial pressurization of step (i) is advantageously performed with mostly nitrogen gas, as opposed to high H2 gas. Without being bound by theory, the inventors have found that pressurizing the reactor with a heavier gas, such as N2, is much more efficient than pressurizing with H2 or a gas containing large amounts of H2. This is because, at an industrial scale, gas containing large amounts of H2 is difficult to pressurize, given the constraints of industrial compressors. Thus, the first gaseous composition advantageously includes mostly N2 gas. In certain embodiments described elsewhere herein, the first gaseous composition includes at least 85% N2, such as at least 90% N2, or at least 95% N2. 2, or at least 99% N2. In certain embodiments described elsewhere herein, the first gaseous composition comprises 10% or less H2, e.g., 5% or less H2, or 3% or less H2, or 1% or less H2, or 0.1% or less H2, or 0.01% or less H2. In certain embodiments, the first gaseous composition is substantially free of H2.

[0022] In certain embodiments described elsewhere herein, the pressure during the contacting of step (i) is in the range of from 4 barg to 20 barg, e.g., from 4 barg to 15 barg, or from 4 barg to 12 barg, or from 4 barg to 10 barg, or from 4 barg to 8 barg, or from 5 barg to 20 barg, or from 6 barg to 20 barg, or from 8 barg to 20 barg, or from 10 barg to 20 barg. In certain embodiments described elsewhere herein, the temperature during the contacting of the catalyst in step (i) is no greater than 140° C., or no greater than 135° C. In certain embodiments described elsewhere herein, the temperature during the contacting of the catalyst in step (i) is at least 80° C., e.g., at least 100° C., or at least 110° C., or at least 120° C.

[0023] The second gaseous composition is introduced into the reaction zone to adjust the H2:N2 molar ratio to a desired level. Thus, in certain embodiments as described elsewhere herein, the second gaseous composition comprises at least 85% H2, e.g., at least 90% H2, or at least 95% H2.2, or at least 99% H2. In certain embodiments as described elsewhere herein, the second gaseous composition comprises 10% or less N2, e.g., 5% or less N2, or 3% or less N2, or 1% or less N2, or 0.1% or less N2, or 0.01% or less N2. In certain embodiments, the second gaseous composition is substantially free of N2.

[0024] As described elsewhere herein, the H2 / N2 gas composition formed during step (ii) may be advantageously adjusted to a desired molar ratio of H2 and N2 by a second gas composition. Thus, in certain embodiments described elsewhere herein, the H2 / N2 gas composition formed during step (ii) has an H2:N2 molar ratio in the range of 0.3:1 to 2:1 (e.g., in the range of 0.4:1 to 2:1, or 0.5:1 to 2:1, or 0.6:1 to 2:1, or 0.7:1 to 2:1, or 0.8:1 to 2:1, or 0.2:1 to 1.8:1, or 0.2:1 to 1.6:1, or 0.2:1 to 1.4:1, or 0.2:1 to 1.2:1, or 0.4:1 to 1.4:1, or 0.6:1 to 1.4:1, or 0.6:1 to 1.2:1, or 0.8:1 to 1.2:1).

[0025] The introduction of the second gaseous composition into the reaction zone may result in an increase in pressure as additional gas is added. As H2 is consumed in the reduction process to form water, it may be optionally replenished by the addition of further amounts of the second gaseous composition to maintain the target molar ratio of H2 and N2. Thus, in certain embodiments described elsewhere herein, the pressure resulting from step (ii) is in the range of 12 barg to 30 barg, e.g., 14 barg to 30 barg, or 14 barg to 30 barg, or 14 barg to 24 barg, or 14 barg to 22 barg, or 14 barg to 20 barg, or 20 barg to 30 barg, or 22 barg to 30 barg, or 24 barg to 30 barg, or 24 barg to 28 barg.

[0026] During step (iii), as described elsewhere herein, in certain embodiments, the pressure may be increased to adjust the activation conditions. Thus, in certain embodiments described elsewhere herein, step (iii) further comprises increasing the pressure to a pressure in the range of 20 barg to 50 barg, such as 20 barg to 45 barg, or 20 barg to 40 barg, or 20 barg to 35 barg. The pressure increase may be achieved by the introduction of a first gaseous composition, the introduction of a second gaseous composition, or a mixture thereof.

[0027] It is advantageous to increase the temperature at a relatively slow rate to protect the catalyst. Thus, in certain embodiments described elsewhere herein, the temperature is increased at a ramp rate in the range of 1° C. to 20° C. / hour, e.g., in the range of 3° C. to 20° C. / hour, or in the range of 5° C. to 20° C. / hour.

[0028] As described elsewhere herein, the temperature during step (iii) is increased to a temperature effective for efficient activation to occur. Thus, in certain embodiments described elsewhere herein, the temperature during step (iii) is increased to a range of 230°C to 260°C, e.g., 240°C to 260°C.

[0029] During step (iv), as described elsewhere herein, the catalyst is maintained at the final conditions of step (iii), as described elsewhere herein, for a holding period sufficient for catalyst activation to occur. Thus, in certain embodiments, as described elsewhere herein, the catalyst is maintained at the conditions of step (iii) for a holding period ranging from 2 hours to 96 hours, e.g., from 2 hours to 72 hours, or from 2 hours to 48 hours, or from 3 hours to 96 hours, or from 3 hours to 72 hours, or from 3 hours to 48 hours, or from 4 hours to 72 hours, or from 4 hours to 48 hours, or from 6 hours to 48 hours.

[0030] Following activation, the catalyst is cooled as part of step (v), as described elsewhere herein. In certain embodiments, the catalyst is cooled while the catalyst is in contact with the H2, N2, or H2 / N2 gas composition. For example, in certain embodiments described elsewhere herein, the H2 / N2 gas composition of step (v) has a H2:N2 molar ratio that is substantially the same as the H2:N2 molar ratio of the H2 / N2 gas composition of step (ii), e.g., within 30% (e.g., within 20%, or within 10%) of the H2:N2 molar ratio of the H2 / N2 gas composition of step (ii).

[0031] As discussed above, the inventors have discovered that gaseous water concentration is a critical parameter during activation and must be carefully monitored. This is likely measured at the reactor outlet or reactor inlet to indicate the water level released from the reduction process, as well as the effectiveness of the dryer on the recycle gas stream. If the water concentration in the effluent gas is too low, insufficient reduction may be occurring. Conversely, if the water concentration is too high, there is a risk of damage to the Fischer-Tropsch catalyst. Thus, in certain embodiments described elsewhere herein, the method further comprises monitoring the water concentration of the H2 / N2 gas composition during steps (ii)-(v). In certain embodiments described elsewhere herein, the method further comprises adjusting the temperature ramp rate to slow the reduction ramp if the water concentration exceeds a certain threshold level until the water concentration returns to the target range.

[0032] After activation and cooling, the catalyst may be contacted in the reaction zone with a gaseous reaction mixture comprising both H2 and CO in a H2:CO volume ratio ranging from 1:1 to 3:1. One skilled in the art will select the desired ratio based on, inter alia, the H2:CO volume ratio desired for use in the final FT synthesis process at steady state. For example, in various embodiments described elsewhere herein, the gaseous reaction mixture comprises H2 and CO in a H2:CO volume ratio ranging from 1:1 to 2.5:1, or 1:1 to 2:1, or 1.5:1 to 3:1, or 1.5:1 to 2.5:1, or 1.5:1 to 2:1, or 2:1 to 3:1, or 2:1 to 3:1. In various embodiments described elsewhere herein, the gaseous reaction mixture comprises H2 and CO in a H2:CO volume ratio ranging from 1.5:1 to 2.5:1.

[0033] The gaseous reaction mixture may also contain other inert gases, for example, the gaseous reaction mixture may contain carbon dioxide, methane, N2 or light hydrocarbon gases in an amount greater than 30%, such as greater than 20%, or greater than 10%.

[0034] In various embodiments described elsewhere herein, the gaseous reaction mixture comprises at least 20% by volume H2 and CO (i.e., the combined percentage of H2 and CO is at least 20% by volume). For example, in various embodiments described elsewhere herein, the gaseous reaction mixture comprises at least 30% by volume H2 and CO (e.g., at least 35% by volume H2 and CO). In various embodiments described elsewhere herein, the gaseous reaction mixture comprises at least 40% by volume H2 and CO (e.g., at least 45% H2 and CO).

[0035] Nitrogen gas can be used as an inert gas in the gaseous reaction mixture. In certain embodiments described elsewhere herein, the gaseous reaction mixture further comprises N2 in an amount of up to 80% by volume, e.g., up to 70% by volume, or up to 60% by volume, or up to 50% by volume. For example, in certain embodiments, the gaseous reaction mixture comprises N2 in an amount ranging from 20% by volume to 80% by volume, e.g., from 20% by volume to 70% by volume, or from 20% by volume to 60% by volume, or from 30% by volume to 80% by volume, or from 30% by volume to 70% by volume, or from 30% by volume to 60% by volume, or from 40% by volume to 80% by volume, or from 40% by volume to 70% by volume, or from 40% by volume to 60% by volume.

[0036] The total amount of reactive feed gases (such as H2, CO and olefins) in the gaseous reaction mixture of the processes described elsewhere herein is desirably high, for example, at least 90% by volume, or at least 80% by volume, or at least 75% by volume, or at least 70% by volume.

[0037] The gaseous reaction mixture may contain other gaseous components, such as water, methane and other saturated and / or unsaturated light hydrocarbons, preferably present in a total concentration of less than 30% by volume.

[0038] Once the temperature at which the Fischer-Tropsch reaction begins is reached (typically about 150-180° C.), a hydrocarbon product composition begins to form in the reaction zone, and once the Fischer-Tropsch reaction reaches its steady state operation (e.g., under the conditions of steps (iv) and (v)), the hydrocarbon product composition continues to form to advantageously provide the desired products.

[0039] Subject to the limitations set forth herein, one of skill in the art can adapt conventional Fischer-Tropsch processes to arrive at the methods of the present disclosure. For example, the temperature of the Fischer-Tropsch synthesis may suitably range from 200 to 400°C, e.g., 200 to 300°C, or 210 to 400°C, or 210 to 300°C, or 220 to 400°C, or 220 to 300°C. In various embodiments described elsewhere herein, the temperature of the Fischer-Tropsch synthesis may range from 200 to 250°C, e.g., 200 to 240°C, or 200 to 230°C, or 200 to 220°C, or 210 to 250°C, or 210 to 240°C, or 210 to 230°C, or 220 to 250°C, or 220 to 240°C, or 230 to 250°C. The pressure of the reaction may suitably be in the range of from 10 to 45 barg, for example, from 20 to 40 barg, or from 30 to 45 barg, or from 30 to 40 barg, or from 30 to 35 barg, or from 35 to 45 barg, or from 35 to 40 barg, or from 40 to 45 barg.

[0040] The Fischer-Tropsch synthesis reaction may be carried out in any suitable type of reactor, for example, a fixed bed reactor, a slurry bed reactor, or a CANS™ reactor (US8906970, US8722747, US8906970, US10252236, US10654018). With particular reference to CANS reactors, the passivated catalyst materials described herein may be packaged (e.g., off-site and then transported to the reactor site) into modular catalyst containers suitable for use in the reactor tubes of a CANS reactor.

[0041] The hydrocarbon composition may vary based on changes in process conditions as known in the art. In certain embodiments, the hydrocarbon composition comprises hydrocarbons (e.g., linear, branched, saturated or unsaturated) and oxygenated derivatives thereof. Examples of the oxygenated derivatives include hydrocarbons having one or more functional groups of alcohols, aldehydes, ketones, carboxylic acids, esters, and combinations thereof. In certain embodiments described elsewhere herein, the hydrocarbon composition comprises at least one of alkanes, alkenes, and alcohols.

[0042] Those skilled in the art will be able to adapt suitable catalyst materials for use in the processes described herein. In various preferred embodiments of the processes described herein, the catalyst comprises cobalt and optionally one or more other metals or reaction modifiers disposed on a support. Supported cobalt-based materials are well known in the art and can generally be adapted for use in the processes and materials described herein.

[0043] The catalytic materials described herein include various forms of cobalt, a support, and optionally other metals or reaction modifiers. Supported cobalt-based materials are well known in the art and can generally be adapted for use in the processes and materials described herein.

[0044] In various embodiments described elsewhere herein, the catalytic materials described herein include cobalt in the range of 5% to 35% by weight, calculated as cobalt(0). For example, in certain embodiments described elsewhere herein, cobalt can be present in the range of 7 to 35% by weight, or 10 to 35% by weight, or 5 to 25% by weight, or 7 to 25% by weight, or 10 to 25% by weight, or 5 to 20% by weight, or 7 to 20% by weight, or 10 to 20% by weight.

[0045] The catalytic materials described herein can include other metal species, e.g., as promoters. For example, in certain embodiments described elsewhere herein, the catalytic materials include manganese in an amount ranging from, e.g., 15 wt.% or less, e.g., 12 wt.% or less, or 10 wt.% or less, or 7 wt.% or less, calculated as manganese(0). In certain such embodiments, the catalytic materials include manganese in an amount ranging from 0.1 to 15 wt.%, e.g., 0.5 to 12 wt.%, or 0.5 to 10 wt.%. Of course, in other embodiments, manganese is substantially absent (e.g., less than 0.1 wt.% or less than 0.5 wt.% manganese is present).

[0046] The methods described herein provide an efficient means of reducing Fischer-Tropsch catalysts. Thus, in certain embodiments described elsewhere herein, prior to step (i), at least a portion of the cobalt is present as cobalt oxide and / or cobalt hydroxide. For example, the cobalt may be present as cobalt oxide (e.g., CoO, Co3O4, or Co2O3, or a combination thereof) or cobalt hydroxide (e.g., Co(OH)2 or Co(OH)3, or a combination thereof), or a combination of cobalt oxide and cobalt hydroxide. The catalyst may be prepared using methods conventional in the art. In certain embodiments, the cobalt is introduced onto the support by introducing a solution containing a soluble cobalt salt (e.g., cobalt nitrate) to the support, and the combination is calcined and / or oxidized to provide insoluble cobalt particles (e.g., as cobalt oxide) on the support. For example, the cobalt may be a cobalt oxide (e.g., CoO, Co3O4, or Co2O3, or a combination thereof), or a cobalt hydroxide (e.g., Co(OH)2 or Co(OH)3, or a combination thereof), or a combination of cobalt oxide and cobalt hydroxide.

[0047] In various embodiments of the present disclosure, after the activation process described herein, at least a portion of the cobalt is present as cobalt(0). Thus, in certain embodiments described elsewhere herein, the cobalt of the catalyst after step (v) comprises at least 50% cobalt as cobalt(0), e.g., at least 75%, or at least 90%, based on the total amount of cobalt.

[0048] A variety of support materials are known in the art and can be selected based on the exact requirements of the FT reactor or other chemical, mechanical or economic requirements. In certain embodiments described elsewhere herein, the support comprises at least one of titanium oxide, zirconium oxide, cerium oxide, aluminum oxide, silicon oxide, and zinc oxide. In certain embodiments, the support comprises exactly one of titanium oxide, zirconium oxide, cerium oxide, aluminum oxide, silicon oxide, and zinc oxide. For example, in certain embodiments as described elsewhere herein, the support is titanium oxide (titania).

[0049] (Example) The following examples illustrate certain embodiments of the disclosed method and various uses thereof. They are provided for illustrative purposes only and should not be construed as limiting the scope of the disclosure.

[0050] Example 1 A Fischer-Tropsch reactor was loaded with catalyst containing 10% Co and 1% Mn on an elemental basis based on TiO2. The catalyst was dried in N2 at 130°C for 2 hours. N2 gas was then introduced into the reactor to reach an initial pressure of 10 barg. Subsequently, H2 was introduced to reach a total pressure of 20 barg, H2:N2 molar ratio of 1:1, and GHSV of 5000 hr-1. The temperature was then increased from an initial temperature of 130°C to a temperature of 250°C at a ramp rate of 10°C / hr and held for 24 hours to form the reduced catalyst. During this time, the water concentration was monitored and maintained below 5000 ppm. The catalyst was then cooled to a temperature of 130°C and synthesis gas was introduced at a H2:CO molar ratio of 1.8:1. The temperature was increased to 220°C and the Fischer-Tropsch synthesis was started. Example 2

[0051] The activation protocol of Example 1 was repeated, except that the initial pressure under N2 was 15 barg and the total pressure after H2 introduction was 30 barg. Comparative Example 1

[0052] The catalyst was reduced by ramping to 1 barg under 100% H2 and heating to 300 °C for 15 h, then cooled and subjected to Fischer-Tropsch synthesis conditions as in Example 1.

[0053] The results of Examples 1 and 2 and Comparative Example 1 are summarized in Table 1.

[0054] [Table 1]

[0055] As seen in Table 1, despite the increased %H2 and increased temperature, which should aid in catalyst activation according to conventional catalyst activation protocols, Comparative Example 1 resulted in undesirably low C5+ selectivity and high CH4 selectivity compared to Examples 1 and 2. Furthermore, the lower activation temperatures of Examples 1 and 2 save energy and result in lower operating costs.

[0056] Example 3 A Fischer-Tropsch reactor was loaded with catalyst containing 10% Co and 1% Mn on an elemental basis based on TiO2. The catalyst was dried under N2 gas at a GHSV of 2000 hr-1 and a temperature of 130 °C for 2 hours. N2 gas was then introduced into the reactor to reach an initial pressure of 13 barg. Subsequently, H2 was introduced to achieve a total pressure of 26 barg and a H2:N2 molar ratio of 1:1 with a GHSV of 6700 hr-1. The temperature was then increased from an initial temperature of 130 °C to a temperature of 250 °C at a ramp rate of 10 °C / hr and held for 24 hours to form the reduced catalyst. During this time, the water concentration was monitored and maintained below 5000 ppm. The catalyst was then cooled to a temperature of 130 °C and synthesis gas was introduced at a H2:CO molar ratio of 1.8:1 with 51% N2 and a GHSV of 8795 hr-1. The temperature was increased from 130 °C to 190 °C at a ramp rate of 10 °C / hr, then further increased from 190 °C to 210 °C at a ramp rate of 1 °C / hr, and the pressure was increased to 30 barg for the Fischer-Tropsch synthesis. After the allotted on-stream time, the temperature was further increased to the second temperature (see Table 2 below).

[0057] Example 4 The Fischer-Tropsch reactor and catalyst were prepared as in Example 3, except with an activation residence time of 48 hours.

[0058] Example 5 Example 4 A Fischer-Tropsch reactor and catalyst were prepared as in Example 3, except that the activation pressure was 16 barg and the GHSV during activation was 4300 hr-1.

[0059] Example 6 Example 4 A Fischer-Tropsch reactor and catalyst were prepared as in Example 3, except that the activation pressure was 16 barg, the GHSV during activation was 4300 hr-1, and the activation residence time was 48 hours.

[0060] Example 7 The Fischer-Tropsch reactor and catalyst were prepared as in Example 3, except that the initial activation pressure was 16 barg, the GHSV during activation was 24 hours, after which the pressure was increased to 26 barg, the GHSV was 6700 hr-1, and the catalyst was held for an additional 24 hours.

[0061] Example 8 Example 8 A Fischer-Tropsch reactor and catalyst were prepared as in Example 7, except that the temperature ramp rate after drying to 250 °C was 3 °C / hr.

[0062] The results of Examples 3-8 are summarized below in Table 2. Note that the lower Fischer-Tropsch synthesis temperatures do not allow direct comparisons with previous examples.

[0063] [Table 2]

[0064] Various exemplary embodiments of the present disclosure include, but are not limited to, the enumerated embodiments listed below, which can be combined in any number and in any combination that is not technically or logically inconsistent.

[0065] (Embodiment 1) A method for activating a Fischer-Tropsch synthesis catalyst, (i) contacting the catalyst with a first gaseous composition comprising at least 80% N2 at a pressure in the range of 2 barg to 20 barg and at a temperature up to 250°C; (ii) introducing a second gas composition into the first gas composition at less than 175°C, the second gas composition comprising at least 80% H, forming a H2 / N2 gas composition having a H2:N2 molar ratio in the range of 0.2:1 to 2:1, and providing a pressure in the range of 10 barg to 30 barg; (iii) increasing the temperature to a range of 220°C to 260°C at a heating rate of 20°C / hr or less and a GHSV in the range of 2000 hr-1 to 8000 hr-1. (iv) maintaining the catalyst under the conditions of step (iii) for a holding period ranging from 2 hours to 96 hours. (v) cooling the catalyst to a temperature of 150° C. or less;

[0066] (Embodiment 2) 2. The method of embodiment 1, wherein the first gaseous composition comprises 10% or less H2 (e.g., 5% or less H2, or 3% or less H2, or 1% or less H2, or 0.1% or less H2, or 0.01% or less H2).

[0067] (Embodiment 3) 3. The method of claim 1 or claim 2, wherein the first gaseous composition is substantially free of H2.

[0068] (Embodiment 4) Embodiment 4: The process of any one of embodiments 1-3, wherein the second gaseous composition comprises 10% or less N2 (e.g., 5% or less N2, or 3% or less N2, or 1% or less N2, or 0.1% or less N2, or 0.01% or less N2).

[0069] (Embodiment 5) The method of any of embodiments 1-4, wherein the second gaseous composition is substantially free of N2.

[0070] (Embodiment 6) Embodiment 6. The method of any of embodiments 1-5, wherein the H2 / N2 gas composition formed during step (ii) has a H2:N2 molar ratio in the range of 0.3:1 to 2:1 (e.g., in the range of 0.4:1 to 2:1, or 0.5:1 to 2:1, or 0.6:1 to 2:1, or 0.7:1 to 2:1, or 0.8:1 to 2:1, or 0.2:1 to 1.8:1, or 0.2:1 to 1.6:1, or 0.2:1 to 1.4:1, or 0.2:1 to 1.2:1, or 0.4:1 to 1.4:1, or 0.6:1 to 1.4:1, or 0.6:1 to 1.2:1, or 0.8:1 to 1.2:1).

[0071] (Embodiment 7) Embodiment 7: The process of any of embodiments 1-6, wherein the pressure resulting from step (ii) is in the range of from 12 barg to 30 barg, such as from 14 barg to 30 barg, or from 16 barg to 30 barg, or from 16 barg to 24 barg, or from 26 barg to 30 barg.

[0072] (Embodiment 8) 8. The method of any of embodiments 1-7, wherein the temperature in step (iii) is increased at a ramp rate in the range of 1° C. to 20° C. / hour, such as in the range of 3° C. to 20° C. / hour, or in the range of 5° C. to 20° C. / hour.

[0073] (Embodiment 9) 9. The method of any of the preceding claims, wherein the temperature during step (iii) is increased to a range of 230°C to 260°C, such as to a range of 240°C to 260°C.

[0074] (Embodiment 10) Embodiment 10: The method of any one of embodiments 1 to 9, wherein step (iii) further comprises increasing the pressure to a pressure in the range of 30 barg to 50 barg.

[0075] (Embodiment 11) Embodiment 11. The method of any of embodiments 1 to 10, wherein step (v) is carried out while the catalyst is in contact with the H2 / N2 gas composition.

[0076] (Embodiment 12)

[0031] Embodiment 12: The method of any one of embodiments 1 to 11, wherein the catalyst comprises cobalt in an amount ranging from 5% to 20% by weight on an elemental basis.

[0077] (Embodiment 13) The method of embodiment 12, wherein prior to step (i), at least a portion of the cobalt is cobalt oxide and / or cobalt hydroxide.

[0078] (Embodiment 14) Embodiment 14. The method of any one of embodiments 1 to 13, wherein the catalyst comprises manganese in an amount ranging from 0.5% to 10% by weight.

[0079] (Embodiment 15) Embodiment 15: The method of any one of embodiments 1 to 14, wherein the catalyst is a supported catalyst, and the support is titanium oxide, zirconium oxide, cerium oxide, aluminum oxide, silicon oxide, and zinc oxide.

[0080] (Embodiment 16) The method of embodiment 15, wherein the carrier is titanium oxide.

[0081] (Embodiment 17) Pressurization is achieved by a compressor, the compressor having a pressure of at least 1000 Nm 3 / m 3 The method of any of the preceding embodiments, wherein the mixture has a volume of .hr.

[0082] (Embodiment 18) Embodiment 18: The method of any of embodiments 1-17, further comprising monitoring the water concentration of the H2 / N2 gas composition at the reactor outlet during steps (ii)-(v).

[0083] (Embodiment 19) 19. The process of embodiment 18, further comprising adjusting the temperature gradient to slow down the reduction process by stopping or slowing down if the water concentration exceeds 2000 ppm.

[0084] Embodiment 20. The method of any one of embodiments 1 to 19, further comprising conducting a Fischer-Tropsch synthesis by contacting the catalyst in the reaction zone with a gaseous reaction mixture comprising H2 and CO in a ratio ranging from 1:1 to 3:1.

[0085] (Embodiment 21) 21. The process of embodiment 20, wherein H2 and CO are present in the gaseous reaction mixture in a H2:CO ratio in the range of 1:1 to 2.5:1, or 1:1 to 2:1, or 1.5:1 to 3:1, or 1.5:1 to 2.5:1, or 1.5:1 to 2:1, or 2:1 to 3:1, or 2:1 to 3:1.

[0086] (Embodiment 22) 22. The method of embodiment 20 or embodiment 21, wherein H2 and CO are present in the gaseous reaction mixture in a H2:CO ratio ranging from 1.5:1 to 2.5:1.

[0087] (Embodiment 23) Embodiment 23. The method of any of embodiments 20-22, wherein the reaction zone is at a temperature of at least 200° C. and a pressure in the range of 10 barg to 45 barg.

[0088] Embodiment 24. The method of embodiment 23, wherein the Fischer-Tropsch synthesis is carried out at a temperature in the range of 200 to 250°C, for example, or 200 to 240°C, or 200 to 230°C, or 200 to 220°C, or 210 to 250°C, or 210 to 240°C, or 210 to 230°C, or 220 to 250°C, or 220 to 240°C, or 230 to 250°C.

[0089] (Embodiment 25) Embodiment 25. The method of embodiment 22 or embodiment 24, wherein the Fischer-Tropsch synthesis is carried out at a pressure in the range of 30 to 45 barg, for example, 30 to 40 barg, or 30 to 35 barg, or 35 to 45 barg, or 35 to 40 barg, or 40 to 45 barg.

[0090] (Embodiment 26) 26. The method of any one of the preceding claims, wherein the activation gas is recycled through the gas drying bed from the outlet to the inlet of the reactor, and optionally mixed with fresh gas of composition 1 or composition 2 to maintain the conditions.

[0091] The details shown in this specification are presented as examples and for the purpose of illustrative discussion of certain embodiments of the present disclosure only, and are presented to provide what is believed to be the most useful and easily understood explanation of the principles and conceptual aspects of various embodiments of the present disclosure. In this regard, no attempt is made to show details related to the methods of the present disclosure in more detail than is necessary for a basic understanding of the methods described herein, and the explanation given together with the examples will make clear to those skilled in the art how some forms of the methods of the present disclosure can be embodied in practice. Thus, before the disclosed processes and devices are described, it should be understood that the aspects described herein are not limited to specific embodiments, devices, or configurations, and therefore may, of course, vary. It should also be understood that the terms used herein are intended to describe certain aspects only, and are not intended to be limiting unless specifically defined herein.

[0092] As used in the context of describing the methods of the present disclosure (particularly in the context of the embodiments and claims that follow), the terms "a," "an," "the," and similar referents are to be construed to encompass both the singular and the plural, unless otherwise indicated in the specification or clearly contradicted by context.

[0093] All methods described herein can be carried out in any suitable order of steps, unless otherwise indicated herein or clearly contradicted by context. Any and all examples provided herein, or the use of exemplary language (e.g., "etc.") are intended merely to better illuminate the methods of the present disclosure, and do not impose limitations on the scope of the present disclosure. No language in this specification should be construed as indicating any non-claimed element essential to the practice of the methods of the present disclosure.

[0094] Unless the context clearly dictates otherwise, throughout this specification and the claims, words like "comprise," "comprising," and the like are to be construed in an inclusive sense, i.e., "including, but not limited to," and not in an exclusive or exhaustive sense. Words using the singular or plural also include the plural and singular, respectively. Furthermore, the words "herein," "above," and "below," and words of similar import, when used in this application, shall refer to this application as a whole and not to any particular portions of this application.

[0095] As will be understood by one of ordinary skill in the art, each embodiment disclosed herein can comprise, consist essentially of, or consist of its particular described elements, steps, ingredients, or components. As used herein, the transitional phrases "comprise" or "comprises" mean including, but are not limited to, and allow for the inclusion of unspecified elements, steps, ingredients, or components, even if in large amounts. The transitional phrase "consisting of" excludes any unspecified elements, steps, ingredients, or components. The transitional phrase "consisting essentially of" limits the scope of the embodiment to the specified elements, steps, ingredients, or components, and those that do not materially affect the embodiment.

[0096] All percentages, ratios and proportions herein are by weight unless otherwise specified.

[0097] Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the disclosure are approximations, the numerical values ​​set forth in the specific examples are reported as precisely as possible, however, any numerical value inherently contains certain errors necessarily resulting from the standard deviation found in their respective testing measurements.

[0098] Grouping of alternative elements or embodiments of the present disclosure should not be interpreted as limiting. Each group member may be referred to and claimed individually or in any combination with other members of the group or other elements found herein. It is anticipated that one or more members of a group may be included in or deleted from a group for reasons of convenience and / or patentability. When any such inclusion or deletion occurs, the specification is deemed to include the modified group and thus fulfill the written description of all Markush groups used in the appended claims.

[0099] Several embodiments of the various aspects of the present disclosure are described herein, including the best mode known to the inventors for carrying out the methods described herein. Of course, variations of these described embodiments will become apparent to those skilled in the art upon reading the foregoing description. Those skilled in the art may use such variations as necessary, and thus the methods of the present disclosure may be carried out in ways other than those specifically described herein. Accordingly, the scope of the present disclosure includes all modifications and equivalents of the subject matter described in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the present disclosure unless otherwise indicated herein or clearly contradicted by context.

[0100] As used herein, the phrase "at least a portion" is used to mean that at least a partial amount, up to the entire possible amount, is required.

[0101] Finally, it should be understood that the various embodiments herein are illustrative of the methods of the present disclosure. Other modifications that may be employed are within the scope of the present disclosure. Thus, by way of example, and not of limitation, alternative configurations of the methods may be utilized in accordance with the teachings of the present disclosure. Thus, the methods of the present disclosure are not limited to that precisely as shown and described.

Claims

1. A method for activating a Fischer-Tropsch synthesis catalyst comprising: (i) subjecting the catalyst to a nitrogen atmosphere containing at least 80% N at a pressure in the range of 2 barg to 20 barg and at a temperature of up to 250°C. 2 and contacting the first gaseous composition comprising: (ii) introducing a second gas composition into the first gas composition at less than 175° C., the second gas composition being at least 80% H 2 H in the range of 0.2:1 to 2:1 2 :N 2 H with molar ratio 2 / N 2 forming a gas composition and providing a pressure in the range of 10 barg to 30 barg; (iii) increasing said temperature to a range of 220°C to 260°C at a heating rate of 20°C / hr or less and a GHSV in the range of 2000 hr-1 to 8000 hr-1; (iv) maintaining the catalyst under the conditions of step (iii) for a holding period ranging from 2 hours to 96 hours; (v) cooling said catalyst to a temperature below 150°C.

2. The first gaseous composition comprises 10% or less H 2 (For example, 5% or less H 2 , or 3% or less H 2 , or 1% or less H 2 , or 0.1% or less H 2 or 0.01% or less H 2 2. The method of claim 1, comprising:

3. The second gaseous composition comprises 10% or less N 2 (For example, less than 5% N 2 , or 3% or less N 2 , or 1% or less of N 2 , or 0.1% or less N 2 , or 0.01% or less N 2 3. The method of claim 1 or claim 2, comprising:

4. The H formed during step (ii) 2 / N 2 The gas composition is in the range of 0.3:1 to 2:1 (e.g., in the range of 0.4:1 to 2:1, or 0.5:1 to 2:1, or 0.6:1 to 2:1, or 0.7:1 to 2:1, or 0.8:1 to 2:1, or 0.2:1 to 1.8:1, or 0.2:1 to 1.6:1, or 0.2:1 to 1.4:1, or 0.2:1 to 1.2:1, or 0.4:1 to 1.4:1, or 0.6:1 to 1.4:1, or 0.6:1 to 1.2:1, or 0.8:1 to 1.2:1). 2 :N 2 The method according to any one of claims 1 to 3, wherein the molar ratio is

5. 5. The process according to any one of claims 1 to 4, wherein the temperature during step (iii) is increased to the range of from 230°C to 260°C, such as to the range of from 240°C to 260°C.

6. 6. The method of any one of claims 1 to 5, wherein step (iii) further comprises increasing the pressure to a pressure in the range of 30 barg to 50 barg.

7. Step (v) is reacting the catalyst with H 2 / N 2 The method of any one of claims 1 to 6, carried out whilst maintaining in contact with a gaseous composition.

8. 8. The method of claim 1, wherein the catalyst comprises cobalt in an amount in the range of 5% to 20% by weight on an elemental basis.

9. 9. The process of claim 8, wherein prior to step (i), at least a portion of the cobalt is cobalt oxide and / or cobalt hydroxide.

10. 10. The method according to any one of claims 1 to 9, wherein the catalyst comprises manganese in an amount ranging from 0.5% to 10% by weight.

11. The process according to any one of claims 1 to 10, wherein the catalyst is a supported catalyst, the support being titanium oxide, zirconium oxide, cerium oxide, aluminium oxide, silicon oxide and zinc oxide.

12. The method of claim 11 , wherein the support is titanium oxide.

13. The pressurization is achieved by a compressor, the compressor having a pressure of at least 1000 Nm 3 / m 3 13. The method of any one of claims 1 to 12, having a volume of .hr.

14. The method further comprises the steps of: during steps (ii) to (v), 2 / N 2 The method of any one of claims 1 to 13, further comprising monitoring the water concentration of the gas composition.

15. 15. The method of claim 14, further comprising adjusting the temperature ramp to stop or slow down the rate to slow the reduction process if the water concentration exceeds 2000 ppm.

16. The catalyst in the reaction zone is heated with H 2 and CO in a ratio in the range of 1:1 to 3:

1.

17. 17. The process of claim 16, wherein the reaction zone is at a temperature of at least 200° C. and a pressure in the range of 10 barg to 45 barg.

18. 18. The method according to any of claims 1 to 17, wherein the activation gas is recycled from the outlet of the reactor through a gas drying bed to the inlet, optionally mixed with fresh gas of composition 1 or composition 2 to maintain conditions.

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