EA044090B1 - METHOD FOR PRODUCING METHANOL WITH HIGHER CARBON RECYCLING DUE TO CO2 RECYCLING - Google Patents

Description

Field of technology

The present invention relates to methods for producing methanol, and more particularly to methods for producing methanol from synthesis gas produced by the catalytic partial oxidation of hydrocarbons such as methane.

Field of technology

Synthetic gas (syngas) is a mixture containing carbon monoxide (CO) and hydrogen (H2), as well as small amounts of carbon dioxide (CO2), water (H2O) and unreacted methane ( _CH4 ). Synthesis gas is commonly used as an intermediate in the production of methanol and ammonia, and as an intermediate in the creation of synthetic petroleum for use as a lubricant or fuel.

Syngas is typically produced by steam reforming natural gas (steam methane reforming or SMR), although other hydrocarbon sources can be used to produce syngas, such as refinery off-gases, naphtha feedstocks, heavy hydrocarbons, coal, biomass, etc. PRM is an endothermic process and requires significant energy input to promote the reaction. Traditional endothermic technologies, such as PRM, produce synthesis gas with a hydrogen content greater than that required for methanol synthesis. Typically, the PRM produces synthesis gas with an M ratio ranging from 2.6 to 2.98, where the M ratio is a molar ratio defined as (H ₂ -CO ₂ )/(CO+CO ₂ ).

In the autothermal reforming (ATR) process, a portion of natural gas is burned as fuel to promote the conversion of natural gas to synthesis gas, resulting in relatively low concentrations of hydrogen and relatively high concentrations of CO2. Conventional methanol plants use combined reforming (CR) technology, which combines ATR with autothermal reforming (ATR) to reduce the amount of hydrogen present in the synthesis gas. ATP produces synthesis gas with a hydrogen content below that required for methanol synthesis. Typically, ATP produces synthesis gas with an M ratio ranging from 1.7 to 1.84. According to the CR technology, the volumetric flow rate of natural gas supplied to the PRM and ATP can be adjusted to achieve an M ratio of total synthesis gas from 2.0 to 2.06. In addition, the KR synthesis gas has a hydrogen content greater than that required for methanol synthesis. Moreover, PFP is a highly endothermic process, and the endothermic nature of PFP technology requires fuel combustion to promote syngas synthesis. Consequently, the PRM technology reduces the energy efficiency of the methanol synthesis process.

Synthesis gas can also be produced (non-commercially) by catalytic partial oxidation (CPO (CPO) or CPOk (CPOx)) of natural gas. The COC process uses partial oxidation of hydrocarbon feedstock to synthesis gas containing CO and H2. The CPO process is exothermic, which eliminates the need for external heat input (unlike PRM). However, the composition of the commonly produced synthesis gas is not suitable for methanol synthesis, for example due to the molar ratio of hydrogen to CO. Conventional CPR processes can result in the formation of coke deposited on the catalyst bed, which can also lead to catalyst deactivation and reactor pressure fluctuations, making continuous reactor operation difficult. Thus, there is a continuing need to develop methods for producing syngas from COC.

Brief description of the drawing

For a detailed description of preferred aspects of the disclosed methods, reference is made to the accompanying drawing.

The drawing shows a system diagram of a method for producing methanol.

Detailed description

The invention describes methods for the production of methanol, including (a) reacting, through a catalytic partial oxidation (CPO) reaction, a mixture of CPO reagents in a CPO reactor to produce synthesis gas; where the mixture of CPO reagents contains hydrocarbons and oxygen; where the CPO reactor contains one reaction zone, and one reaction zone contains the CPO catalyst; and wherein the synthesis gas contains hydrogen (H ₂ ), carbon monoxide (CO), carbon dioxide (CO ₂ ), water (H ₂ O) and unreacted hydrocarbons; (b) introducing at least a portion of the synthesis gas (eg, after cooling and removing water from the synthesis gas and/or after adjusting the pressure and/or temperature of the synthesis gas) into the methanol reactor to obtain a methanol reactor effluent stream; wherein the methanol reactor effluent contains methanol, water, hydrogen, carbon monoxide, carbon dioxide and hydrocarbons; (c) separating at least a portion of the methanol reactor effluent stream into a crude methanol stream, a hydrogen stream, a CO2 stream, and a purge gas stream; wherein the crude methanol stream contains methanol and water; wherein the purge gas stream contains carbon monoxide and hydrocarbons; and wherein the CO2 stream comprises at least a portion of the CO2 effluent of the methanol reactor; and (d) recycling at least a portion of the CO2 stream to the CPO reactor. Hydrocarbons used to produce synthesis gas may include methane, natural gas, liquefied natural gas, petroleum field gas, associated gas, enriched gas, waxes, shale gas, shale fluids, fluid catalytic cracking (FCC) offgas , process gases from oil refining, flue gases, fuel gas from the fuel gas collector, etc. or combinations thereof.

Except for working examples or other indications, all numbers or expressions referring to quantities of ingredients, reaction conditions, etc., used in the description and claims are to be understood as modified in all cases by the term approximately. The invention discloses different numerical intervals. Because these intervals are continuous, they include every value between the minimum and maximum values. The endpoints of all intervals that list the same characteristic or component can be combined independently to include the specified endpoint. Unless specifically stated otherwise, the various numerical ranges given in this application are approximate. The endpoints of all intervals that refer to the same component or property include the endpoint and are combined independently. The term greater than 0 to an amount means that the named component is present in an amount greater than 0 and up to and including said higher amount.

The terms a, an and the do not denote a limitation in quantity, but rather denote the presence of at least one of the mentioned elements. As used here, the singular forms a an and the include references to the plural.

As used herein, combinations thereof include one or more of the listed elements, optionally together with a similar element that is not listed, for example, includes a combination of one or more named components, optionally with one or more other components not specifically named, which essentially have the same function. As used herein, the term combination includes mixtures, alloys, reaction products, and the like.

Reference in the description to an aspect, another aspect, other aspects, some aspects, and so on means that the particular element (e.g., feature, structure, property and/or characteristic) described in connection with the aspect is included in at least the aspect described herein and may or may not be present in other aspects. In addition, it should be understood that the described element(s) can be combined in any suitable manner in various aspects.

As used herein, the terms inhibition, or reduction, or prevention, or elimination, or any variation of these terms include any measurable reduction or complete inhibition to achieve a desired result.

As used herein, the term effective means adequate to achieve the desired, expected or intended result.

As used herein, the terms containing (and any form of content such as contain and includes), having (and any form of having such as have and has), including (and any form of inclusion such as include and includes) or consisting of (and any form of composition such as consist of and consists of) are inclusive and open-ended and do not exclude additional, unlisted elements or method steps.

Unless otherwise defined, technical and scientific terms used herein have the same meanings as commonly understood by one skilled in the art.

The compounds are described in the invention using standard nomenclature. For example, any position unsubstituted by any specified group is understood to have its valence filled by a bond or hydrogen atom. A dash (-) that is not between two letters or symbols is used to show the attachment point for a substituent. For example, the CHO group is attached through the carbon atom of the carbonyl group.

As used herein, the terms C _x hydrocarbons and C _x are used interchangeably and refer to any hydrocarbon having x number of carbon atoms (C). For example, both the terms C ₄ hydrocarbons and C ₄ refer to any hydrocarbons having exactly 4 carbon atoms, such as n-butane, isobutane, cyclobutane, 1-butene, 2-butene, isobutylene, butadiene, etc., or their combinations.

As used herein, the term C _x+ hydrocarbons refers to any hydrocarbon having equal to or greater than x number of carbon atoms (C). For example, the term C2 ₊ hydrocarbons refers to any hydrocarbons having 2 or more carbon atoms, such as ethane, ethylene, _C3 , _C4 , _C5 , etc.

With respect to the figure, the figure discloses a methanol production system 1000. The methanol production system 1000 typically includes a catalytic partial oxidation reactor (CPR or CPR) 100; methanol reactor 200; gas-liquid separator 300; distillation unit 400; hydrogen extraction unit (H ₂ ); and a carbon dioxide (CO2) separator 600. As will be appreciated by one skilled in the art and with the aid of this description, the components of the methanol production system shown in the figure may be in fluid communication with each other (as illustrated by the connecting lines indicating the direction of fluid flow) through any suitable conduits (eg pipes, streams, etc.).

In one aspect, the method for producing methanol described in the invention may include the step of reacting, through a CPO reaction, a mixture of CPO reactants 10 in a CPO reactor 100 to produce synthesis gas (eg, the effluent from a CPO reactor 15); where the mixture of reagents KCHO 10 contains hydrocarbons, oxygen and optionally water vapor; where the KChO 100 reactor contains one reaction

- 2 044090 zone, with one reaction zone containing a CPO catalyst; and wherein the synthesis gas 15 contains hydrogen, carbon monoxide, carbon dioxide, water and unreacted hydrocarbons.

Typically, the CPR reaction is based on the partial combustion of fuels such as various hydrocarbons, and in the case of methane, the CPR can be represented by equation (1):

CH ₄ +1/2O ₂ 2CO+2H ₂ (1)

Without intending to be bound by any theory, it should be noted that side reactions may occur along with the COC reaction depicted in equation (1); and such side reactions can produce carbon dioxide (CO2) and water (H2O), for example through the combustion of hydrocarbons, which is an exothermic reaction. As will be appreciated by one skilled in the art and by use of this description, and without intending to be bound by any theory, the CPO reaction represented by equation (1) can produce synthesis gas with a molar ratio of hydrogen to carbon monoxide (H2/ CO), having a theoretical stoichiometric limit of 2.0. Without intending to be bound by any theory, it should be noted that the theoretical stoichiometric limit of 2.0 for the _H2 /CO molar ratio means that the CCO reaction represented by equation (1) produces 2 mol H2 for every 1 mol CO, i.e. , the H ₂ /CO molar ratio (2 mol H ₂ /mol CO) is 2. As will be appreciated by one skilled in the art and from this description, the theoretical stoichiometric limit is 2.0 for the H 2 /CO molar ratio in the CPO reaction practically cannot be achieved, since reactants (eg hydrocarbons, oxygen) as well as products (eg H2, CO) undergo side reactions under the conditions used for the CPO reaction. As will be appreciated by one skilled in the art and by this description, and without intending to be bound by any theory, in the presence of oxygen, CO and H ₂ can be oxidized to CO ₂ and H ₂ O, respectively. The relative amounts (eg composition) of CO, H ₂ , CO ₂ and H ₂ O can be further altered by shifting the equilibrium of the water gas shift (WGS) reaction, which will be discussed in more detail later. Side reactions that may occur in the KCHO 100 reactor can have a direct effect on the M ratio of the synthesis gas produced, where the M ratio is a molar ratio defined as (H ₂ -CO ₂ )/(CO+CO ₂ ). In the absence of any side reaction (theoretically), the CPO reaction represented by equation (1) results in synthesis gas with an M ratio of 2.0. However, the presence of side reactions (in practice) reduces _H2 and increases _CO2 , resulting in synthesis gas with an M ratio below 2.0.

Additionally, without intending to be bound by any theory, it should be noted that the CPO reaction shown in equation (1) is an exothermic heterogeneous catalytic reaction (i.e., a moderately exothermic reaction) and it occurs in a single reactor unit (e.g. at one stage of the process in one reaction zone), such as the KChO 100 reactor (as opposed to more than one reactor block, as is the case with traditional synthesis gas production processes, such as combinations of steam methane reforming (SMR) and autothermal reforming (ATR) )). Although it is possible to carry out partial oxidation of hydrocarbons as a homogeneous reaction in the absence of a catalyst, the process of homogeneous partial oxidation of hydrocarbons entails excessive temperatures, long residence times, and excessive coke formation, which greatly reduces the controllability of the partial oxidation reaction and may not produce the desired synthesis gas quality in one reactor unit (for example, at one process stage in one reaction zone).

In addition, without intending to be bound by any theory, it should be noted that the CPO reaction is quite resistant to chemical poisoning, and as such it allows the use of a wide range of hydrocarbon feedstocks, including some sulfur-containing hydrocarbon feedstocks; this can in some cases increase catalyst life and performance. In contrast, traditional ATP processes have more stringent feedstock requirements, for example, in terms of the content of impurities in the feedstock (for example, APR feedstock is desulfurized) as well as hydrocarbon composition (for example, CH4-rich feedstock is predominantly used in ATP).

In one aspect, hydrocarbons suitable for use in the CSF reaction described herein may include methane (CH4), natural gas, liquefied natural gas, oil field gas, associated gas, rich gas, waxes, shale gas, shale fluids, off-gas fluid catalytic cracking (FCC) gas, oil refining process gases, flue gases, fuel gas from the fuel gas header, etc. or combinations thereof. Hydrocarbons may include any suitable hydrocarbon source and may include C ₁ -C ₆ hydrocarbons as well as some heavier hydrocarbons.

In one aspect, the reactant mixture CCO 10 may comprise natural gas. Typically, natural gas consists predominantly of methane, but may also contain ethane, propane and heavier hydrocarbons (e.g. isobutane, n-butane, iso-pentane, n-pentane, hexanes, etc.), as well as very small amounts of nitrogen , oxygen, carbon dioxide, sulfur compounds and/or water. Natural gas may be provided from a number of sources, including, but not limited to, gas fields, oil fields, coal fields, hydraulic fracturing fields, biomass, landfill gas, and the like, or combinations thereof. In some aspects, the CCHO 10 reagent mixture may contain CH4 and O2.

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Natural gas may contain any suitable amount of methane. In some aspects, natural gas may contain biogas. For example, natural gas may contain about 45 to 80 mole% methane, about 20 to 55 mole% carbon dioxide, and about less than mole% nitrogen.

In one aspect, the natural gas may contain CH ₄ in an amount equal to or greater than about 45 mole%, or equal to or greater than about 50 mole%, or equal to or greater than about 55 mole%, or equal to or greater than about 60 mol.%, or equal to or greater than about 65 mol.%, or equal to or greater than about 70 mol.%, or equal to or greater than about 75 mol.%, or equal to or greater than about 80 mol.%, or equal to or greater than about 82 mol.%, or equal to or greater than about 84 mol.%, or equal to or greater than about 86 mol.%, or equal to or greater than about 88 mol.% .%, or equal to or greater than about 90 mol.%, or equal to or greater than about 91 mol.%, or equal to or greater than about 92 mol.%, or equal to or greater than about 93 mol.% , or equal to or greater than about 94 mol.%, or equal to or greater than about 95 mol.%, or equal to or greater than about 96 mol.%, or equal to or greater than about 97 mol.%, or equal to or greater than about 98 mol.%, or equal to or greater than about 99 mol.%

In some aspects, hydrocarbons suitable for use in the CPO reaction described herein may contain C ₁ -C ₆ hydrocarbons, nitrogen (for example, from about 0.1 to 15 mol.%, or from about 0.5 to 11 mol.%, or about 1 to 7.5 mol.%, or about 1.3 to 5.5 mol.%), and carbon dioxide (for example, about 0.1 to 2 mol.% , or about 0.2 to 1 mol.%, or about 0.3 to 0.6 mol.%). For example, hydrocarbons suitable for use in the CPO reaction described herein may contain Ci hydrocarbon (about 89 to 92 mol%); C ₂ hydrocarbons (about 2.5 to 4 mol.%); C3 hydrocarbons (about 0.5 to 1.4 mol%); C ₄ hydrocarbons (about 0.5 to 0.2 mol%); C ₅ hydrocarbons (approximately 0.06 mol.%), and C ₆ hydrocarbons (approximately 0.02 mol.%); and optionally nitrogen (about 0.1 to 15 mol.%), carbon dioxide (about 0.1 to 2 mol.%), or both nitrogen (about 0.1 to 15 mol.%) and carbon dioxide ( approximately 0.1 to 2 mol.%).

The oxygen used in the KCHO 10 reagent mixture may contain 100% oxygen (essentially pure O ₂ ), oxygen gas (which can be produced through a membrane separation process), industrial oxygen (which may contain some air), oxygen-enriched air , oxygen-containing gaseous compounds (for example, NO), oxygen-containing mixtures (for example, O ₂ /CO ₂ , O ₂ /H ₂ O, O ₂ /H ₂ O ₂ /H ₂ O), oxy-radical generators (for example, CH3OH, CH2O), hydroxyl radical generators, etc., or combinations thereof.

In one aspect, the CCO reactant mixture 10 may have a carbon to oxygen (C/O) molar ratio of less than about 3:1, or less than about 2.6:1, or less than about 2.4:1, or less than about 2.2:1, or less than about 2:1, or less than about 1.9:1, or equal to or greater than about 2:1, or equal to or greater than about 2.2 :1, or equal to or greater than about 2.4:1, or equal to or greater than about 2.6:1, or from about 0.5:1 to 3:1, or from about 0.7:1 to 2.5:1, or from about 0.9:1 to 2.2:1, or from about 1:1 to 2:1, or from about 1.1:1 to 1.9:1 , or about 2:1 to 3:1, or about 2.2:1 to 3:1, or about 2.4:1 to 3:1, or about 2.6:1 to 3:1, where the C/O molar ratio refers to all moles of carbon (C) hydrocarbons in the reactant mixture divided by all moles of oxygen (O2) in the reactant mixture.

For example, when the only source of carbon in a mixture of CCO 10 reagents is CH4, the _CH4 / _O2 molar ratio is the same as the C/O molar ratio. As another example, when a mixture of CCHO 10 reagents contains carbon _sources other than _CH4 , such as ethane ( _C2H6 ), propane (C3H8), butanes ( _C4H10 ), etc., the C/O molar ratio takes into account the moles of carbon in each component (for example, 2 mol C in 1 mol C ₂ H ₆ , 3 mol C in 1 mol C3H8, 4 mol C in 1 mol C ₄ H ₁₀ , etc.). As will be appreciated by one skilled in the art and by reference to this description, the C/O molar ratio in the CPO 10 reactant mixture can be adjusted along with other reactor process parameters (e.g., temperature, pressure, flow rate, etc.) to obtain synthesis gas with the desired composition (for example, synthesis gas with the desired H2/CO molar ratio). The C/O molar ratio of the CPO reactant mixture can be adjusted to provide a reduced amount of unreacted hydrocarbons in the synthesis gas. The C/O molar ratio of the CPO reactant mixture 10 can be adjusted based on the temperature of the CPO effluent stream to reduce (eg, minimize) the unreacted hydrocarbon content of the produced synthesis gas. As will be appreciated by one skilled in the art and with the help of this description, the C/O molar ratio can be adjusted in conjunction with other reactor process parameters (eg, temperature, pressure, flow rate, etc.) to provide synthesis gas of the desired composition (for example, synthesis gas with the desired molar ratio

_H2 /CO).

The KCHO 10 reactant mixture may also contain water vapor, and the ratio of water vapor to carbon in the reactant mixture will be discussed in more detail below.

The CPO reaction is an exothermic reaction (eg, heterogeneous catalytic reaction; exothermic heterogeneous catalytic reaction) which is typically carried out in the presence of a CPO catalyst containing a catalytically active metal, that is, a metal active in catalyzing the CPO reaction. The catalytically active metal may comprise a noble metal (eg, Pt, Rh, Ir, Pd, Ru, Ag, etc., or combinations thereof); base metal (for example, M, Co, V, Mo, P, Fe, Cu, etc., or combinations thereof); rare earth elements (eg La, Ce, Nd, Eu, etc., or combinations thereof); their oxides; and so on.; or combinations thereof. Generally, a noble metal is a metal that is resistant to corrosion and oxidation in a water-containing environment. As will be appreciated by one skilled in the art and with the help of this description, the components of the CPO catalyst (eg, metals, such as noble metals, base metals, rare earth elements) can be phase separated or combined in the same phase.

In one aspect, CPO catalysts suitable for use in the present invention may be supported catalysts and/or unsupported catalysts. In some aspects, supported catalysts may comprise a support, where the support may be catalytically active (eg, the support may catalyze a CPO reaction). For example, the catalytically active support may include metal fabric or wire mesh (eg, Pt fabric or wire mesh); catalytically active metal monolithic catalyst; and others. In other aspects, supported catalysts may comprise supports where the support may be catalytically inactive (eg, the support cannot catalyze the CPO reaction), such as SiO2, silicon carbide (SiC), alumina, catalytically inactive monolithic support; and others. In yet other aspects, supported catalysts may comprise a catalytically active support and a catalytically inactive support.

In some aspects, the CPO catalyst may be thinly coated on a support, wherein the support may be catalytically active or inactive, and where the support may be a monolith, foam, irregularly shaped catalyst particles, etc.

In some aspects, the CPO catalyst may be a monolith, foam, powder, particle, etc. Non-limiting examples of shapes for CPO catalyst particles suitable for use in the present invention include cylindrical, disk-shaped, spherical, plate-shaped, ellipsoidal, equal-area, irregular, cubic, needle-shaped, etc., or combinations thereof.

In some aspects, the support comprises an inorganic oxide, alpha, beta or theta aluminum oxide (Al ₂ O ₃ ), activated Al ₂ O ₃ , silicon dioxide (SiO2), titanium dioxide (TiO2), magnesium oxide (MgO), oxide zirconium (ZrO2), lanthanum (III) oxide (La2O ₃ ), yttrium (III) oxide (Y ₂ O ₃ ), cerium (IV) oxide (CeO ₂ ), zeolites, ZSM-5, perovskite oxides, hydrotalcite oxides, etc. .p., or combinations thereof.

CSF processes, CSF reactors, CSF catalysts, and CSF catalyst bed configurations suitable for use in the present invention are described in more detail in US Provisional Patent Application No. 62/522910, filed June 21, 2017 (International Application No. PCT/IB2018/054475 , filed June 18, 2018) entitled Improved Reactor Designs for Heterogeneous Catalytic Reactions, and in US Provisional Patent Application No. 62/521831, filed June 19, 2017 (International Application No. PCT/1B2O18/O5447O, filed June 18, 2018 d) entitled An Improved Process for Syngas Production for Petrochemical Applications, each of which is incorporated herein by reference in its entirety.

In one aspect, a CPO reactor suitable for use in the present invention (e.g., a CPO 100 reactor) may include a tubular reactor, a continuous flow reactor, an isothermal reactor, an adiabatic reactor, a fixed bed reactor, a fluidized bed reactor, a bubble bed reactor , circulating bed reactor, fluidized bed reactor, rotary kiln type reactor, etc., or combinations thereof.

In one aspect, the KCHO reactor 100 contains a single reaction zone (as opposed to multiple reaction zones). As will be appreciated by one skilled in the art and by reference to this description, the methanol production process disclosed herein uses a single-step process (which occurs in a single reaction zone) to produce synthesis gas (as opposed to a multi-step process for producing synthesis gas). gas, where a multi-stage process occurs in two or more reaction zones). In one aspect, the methanol production method disclosed in the invention eliminates the use of a multi-step synthesis gas production process. Moreover, as will be appreciated by one skilled in the art and by reference to this description, the synthesis gas 15 recovered from the CPO reactor 100 is not further subjected to further oxidation or partial oxidation; and the synthesis gas 15 recovered from the CPO reactor 100 is suitable for introduction into the methanol reactor 200 without the need to subject it to further oxidation or partial oxidation.

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In some aspects, the CPO reactor 100 may be characterized by at least one CPO operating parameter selected from the group consisting of CPO reactor temperature (eg, CPO catalyst bed temperature); CSC supply temperature (for example, the temperature of the CSC reagent mixture), target temperature of the CSC outlet stream; pressure of the reactor (for example, the pressure in the reactor of the reactor); CWC contact time (for example, contact time in the CWC reactor); molar C/O ratio in the mixture of CCHO reagents; the molar ratio of water vapor to carbon (P/C) in a CWC reactant mixture, where the molar ratio P/C means the total moles of water (H2O) in the reactant mixture divided by the total moles of carbon (C) hydrocarbons in the reaction mixture; and their combinations. As used herein, the temperature of the CPO effluent stream is the temperature of the synthesis gas (e.g., the synthesis gas effluent stream) measured at the point where the synthesis gas leaves the CPO reactor (CPO 100 reactor), e.g., the temperature of the synthesis gas measured at exit from the KChO reactor, temperature of the outlet synthesis gas stream, temperature of the outlet of the outlet synthesis gas stream. For purposes of the present disclosure, the CSF effluent temperature (eg, the target CSF effluent temperature) is considered an operating parameter. As will be understood by one skilled in the art and with the help of this description, the selection of operating parameters for the CSF reactor, such as CSF feed temperature, CSF pressure, CSF contact time, C/O molar ratio in the CSF reactant mixture, P/ molar ratio C in the mixture of CPO reactants, etc., determines the temperature of the CPO reactor effluent (for example, synthesis gas), as well as the composition of the CPO reactor effluent (for example, synthesis gas). In addition, as one skilled in the art will appreciate and with the help of this description, monitoring the temperature of the CSF effluent stream can provide feedback for changes in other operating parameters (e.g., CSF feed temperature, CSF pressure, CSF contact time, C molar ratio /O in the mixture of CSC reagents, the P/C molar ratio in the mixture of CSC reagents, etc.) as necessary, so that the temperature of the CSC effluent stream coincides with the target temperature of the CSC effluent stream. Moreover, as one skilled in the art will appreciate and with the help of this description, the target CSF effluent temperature is the desired CSF effluent temperature, and the CSF effluent temperature (e.g., the measured CSF effluent temperature, the actual effluent temperature) CCHO flow) may or may not coincide with the target temperature of the CCHO outlet stream. In aspects where the temperature of the CSF effluent stream differs from the target temperature of the CSF effluent stream, one or more operating parameters of the CSF (e.g., CSF supply temperature, CSF pressure, CSF contact time, C/O molar ratio of the CSF reagent mixture, P/M molar ratio C in the mixture of CSC reagents, etc.) can be adjusted (for example, changed) so that the temperature of the CSC outlet stream corresponds to (for example, is the same, coincides with) the target temperature of the CSC outlet stream. The KCHO 100 reactor can be operated at any suitable operating parameters that can provide synthesis gas of the desired composition (eg, synthesis gas with a desired H ₂ /CO molar ratio).

The CPO 100 reactor may have a CPO feed temperature of about 25 to 600°C, or about 25 to 500°C, or about 25 to 400°C, or about 50 to 400°C, or about from 100 to 400°C. In aspects where the CSC reactant mixture includes steam, the CSC feed temperature may reach about 600°C, or about 575°C, or about 550°C, or about 525°C. In aspects where the CPO reactant mixture does not contain steam, the CPO feed temperature may reach about 450°C, or about 425°C, or about 400°C, or about 375°C.

The CSF reactor 100 may be characterized by a CSF effluent temperature (e.g., a target CSF effluent temperature) equal to or greater than about 300°C, or equal to or greater than about 600°C, or equal to or greater than about 700°C , or equal to or greater than about 750°C, or equal to or greater than about 800°C, or equal to or greater than about 850°C, or from about 300 to 1600°C, or from about 600 to 1400°C, or approximately 600 to 1300°C, or approximately 700 to 1200°C, or approximately 750 to 1150°C, or approximately 800 to 1125°C, or, on the other hand, approximately from 850 to 1100°C.

In one aspect, the CPO reactor 100 can be characterized by any suitable reactor temperature and/or catalyst bed temperature. For example, the CPO reactor 100 may have a reactor temperature and/or catalyst bed temperature equal to or greater than about 300°C, or equal to or greater than about 600°C, or equal to or greater than about 700°C, or equal to or greater than about 750°C, or equal to or greater than about 800°C, or equal to or greater than about 850°C, or from about 300 to 1600°C, or from about 600 to 1400°C, or from about 600 to 1300°C, or from about 700 to 1200°C, or from about 750 to 1150°C, or from about 800 to 1125°C, or, on the other hand, from about 850 to 1100 °C.

The KCHO 100 reactor can be operated at any suitable temperature that can provide synthesis gas of the desired composition (for example, synthesis gas with a desired molar ratio

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H2/CO). The KChO 100 reactor can operate under adiabatic conditions, non-adiabatic conditions, isothermal conditions, nearly isothermal conditions, etc. As used herein, the term non-adiabatic conditions refers to process conditions in which the reactor is subjected to external heat exchange or heat transfer (eg, the reactor is heated or the reactor is cooled), which may be direct heat exchange and/or indirect heat exchange. As will be appreciated by one skilled in the art and from this description, the terms direct heat transfer and indirect heat transfer are known to one skilled in the art. In contrast, the term adiabatic conditions refers to process conditions in which the reactor is not subject to external heat exchange (eg, the reactor is not heated or the reactor is not cooled). Typically, external heat exchange refers to an external heat exchange system (eg, cooling system, heating system) that requires energy input and/or output. As one skilled in the art will appreciate and with the benefit of this description, external heat transfer can also result from heat loss from the catalyst (or reactor) bed due to radiative heat transfer, conduction, convection heat transfer, and the like, or combinations thereof. For example, the catalyst bed may participate in heat exchange with the external environment and/or with the reactor zones upstream and/or downstream of the catalyst bed.

As used herein, the term isothermal conditions refers to process conditions (e.g., CPO operating parameters) that allow the temperature of the reactor and/or catalyst bed to be maintained substantially constant (e.g., isothermal temperature), which can be defined as a temperature that varies approximately less than by ±10°C, or by approximately less than ±9°C, or by approximately less than ±8°C, or by approximately less than ±7°C, or by approximately less than ±6°C, or by approximately less than ±5°C, or by approximately less than ±4°C, or by approximately less than ±3°C, or by approximately less than ±2°C, or by approximately less than ±1°C throughout the reactor and/or catalyst bed, respectively.

Additionally, as used herein, the term isothermal conditions refers to process conditions (e.g., CPO operating parameters) effective to produce synthesis gas of the desired composition (e.g., desired H2/CO molar ratio, desired CO2 content, etc.) where isothermal conditions include a temperature change of approximately less than ±10°C throughout the reactor and/or catalyst bed.

The KCHO 100 reactor can be operated at any suitable operating parameters that can provide isothermal conditions.

As used herein, the term near-isothermal conditions refers to process conditions (e.g., CPO operating parameters) that allow the temperature of the reactor and/or catalyst bed to be maintained nearly constant (e.g., near-isothermal temperature), which can be defined as a temperature that varies approximately less than ±100°C, or approximately less than ±90°C, or approximately less than ±80°C, or approximately less than ±70°C, or approximately less than ±60° C, or approximately less than ±50°C, or approximately less than ±40°C, or approximately less than ±30°C, or approximately less than ±20°C, or approximately less by less than ±10°C, or by approximately less than ±9°C, or by approximately less than ±8°C, or by approximately less than ±7°C, or by approximately less than ±6°C, or by approximately less than ±5°C, or approximately less than ±4°C, or approximately less than ±3°C, or approximately less than ±2°C, or approximately less than ±1°C the entire reactor and/or catalyst bed, respectively. In some aspects, near-isothermal conditions allow a temperature variation of less than about ±50°C, or less than about ±25°C, or less than about ±10°C throughout the reactor and/or catalyst bed . Additionally, as used herein, the term near-isothermal conditions should be understood to include isothermal conditions.

Additionally, as used herein, the term near-isothermal conditions refers to process conditions (e.g., CPO operating parameters) effective to produce synthesis gas of the desired composition (e.g., desired H2/CO molar ratio, desired CO2 content, etc.) , where near isothermal conditions include a temperature change of approximately less than ±100°C throughout the reactor and/or catalyst bed.

In one aspect, the method disclosed herein may include conducting a CPO reaction under near-isothermal conditions to produce synthesis gas, wherein the near-isothermal conditions include a temperature change of approximately less than ±100°C throughout the reactor and/or catalyst bed.

The KCHO 100 reactor can be operated at any suitable operating parameters that can provide near isothermal conditions.

The KChO 100 reactor can be characterized by the KChO pressure (for example, the reactor pressure, from

- 7 044090 measured at the exit or discharge from the reactor), equal to or greater than approximately 1 bar(g), or equal to or greater than approximately 10 bar(g), or equal to or greater than approximately 20 bar(g). ), or equal to or greater than about 25 barg, or equal to or greater than about 30 barg, or equal to or greater than about 35 barg, or equal to or greater than about 40 barg, or equal to or greater than about 50 barg, or less than about 30 barg, or less than about 25 barg, or less than approximately 20 bar(g), or less than approximately bar(g), or approximately 1 to 90 bar(g), or approximately 1 to 40 bar(g), or approximately 1 to 30 bar(g), or approximately 1 to 25 bar(g), or approximately 1 to 20 bar(g), or approximately 1 to 10 bar(g), or approximately 20 to 90 bar(g), or approximately 25 to 85 bar(g) or, on the other hand, approximately 30 to 80 bar(g).

The CCO reactor 100 may have a CCO contact time of about 0.001 milliseconds (ms) to 5 seconds (s), or about 0.001 ms to 1 s, or about 0.001 to 100 ms, or about 0.001 to 10 ms , or approximately 0.001 to 5 ms or, on the other hand, approximately 0.01 to 1.2 ms. Typically, contact time in a reactor containing a catalyst refers to the average amount of time that a compound (e.g., a molecule of that compound) spends in contact with the catalyst (e.g., a catalyst bed), e.g., the average amount of time it takes a compound (e.g., a molecule of this compound) to pass through the catalyst bed. As used herein, contact times of less than about 5 ms may be referred to as millisecond mode (MSR); and the CSF method or CSF reaction described herein, characterized by a contact time of less than about 5 ms, may be referred to as a millisecond mode CSF method or reaction (MCR-MCR), respectively.

In some aspects, the CPO reactor 100 may have a contact time of about 0.001 to 5 ms, or, alternatively, about 0.01 to 1.2 ms.

All operating parameters of the CFC disclosed in the invention are applicable in all embodiments disclosed in the invention, unless otherwise indicated. As one skilled in the art will appreciate and with the help of this description, each operating parameter of the CPR can be adjusted to produce a desired quality of synthesis gas, such as a synthesis gas of a desired composition (for example, a synthesis gas with a desired H ₂ molar ratio /CO). For example, the operating parameters of the CPR can be adjusted to ensure a lower CO2 content in the synthesis gas. As another example, the operating parameters of the CPO can be adjusted to provide increased H2 content in the synthesis gas. As another example, the operating parameters of the CPO can be adjusted to produce a reduced content of unreacted hydrocarbons (eg, unreacted CH ₄ ) in the synthesis gas.

When an excess of hydrocarbons (e.g. methane) is present, some of the hydrocarbons may undergo a thermal decomposition reaction, for example, as represented by equation (2):

CH ₄ C + 2H ₂ (2).

The decomposition reaction of hydrocarbons such as methane is enhanced at elevated temperatures and increases the hydrogen content of the synthesis gas 15. As will be appreciated by one skilled in the art and by this description and without intending to be bound by any theory, although the percentage hydrocarbons in a KChO 10 reagent mixture that undergoes a decomposition reaction (for example, the decomposition reaction represented by equation (2)) increases with increasing C/O molar ratio in the KChO 10 reagent mixture, some of the hydrocarbons may undergo a decomposition reaction to carbon (C) and H2 even at relatively low C/O molar ratios in the KCHO 10 reagent mixture (eg, the C/O molar ratio in the KCHO 10 reagent mixture is approximately less than 2:1). Carbon generated during the decomposition of hydrocarbons, for example, as represented by equation (2), can be deposited on the CPO catalyst in the form of coke.

In one aspect, the CPO reagent mixture 10 may further comprise a diluent such as water and/or steam. The KCHO 100 reactor can be operated at any suitable operating parameters that can produce synthesis gas of the desired composition (eg, synthesis gas with a desired H ₂ /CO molar ratio); for example, the KCHO reactor 100 can operate by introducing water and/or steam into the KCHO reactor 100.

Typically, the diluent is inert to the COC reaction, for example, the diluent does not participate in the COC reaction (eg, the COC reaction represented by equation (1)). However, as one skilled in the art will appreciate and with the help of this description, some diluents (e.g., water, steam, etc.) may undergo chemical reactions other than the CPO reaction within the CPO reactor 100, and may change the composition of the resulting synthesis gas (for example, synthesis gas 15). As will be appreciated by one skilled in the art and by reference to this description, water and/or steam can be used to change the composition of the synthesis gas produced. Water vapor can react with methane, for example, as shown in equation (3):

- 8 044090

CH4 + H ₂ O o CO + ZN ₂ (3)

In one aspect, a diluent containing water and/or steam can increase the hydrogen content of the resulting synthesis gas (eg, synthesis gas 15). For example, in aspects where the reactant mixture of CPO 10 includes the diluent water and/or steam, the resulting synthesis gas (e.g., synthesis gas 15) may be characterized by a molar ratio of hydrogen to carbon monoxide, which increases when compared with the molar ratio of hydrogen to carbon monoxide in synthesis gas produced by an otherwise similar process carried out with a mixture of reagents containing hydrocarbons and oxygen, without the diluent of water and/or steam.

In addition, in the presence of water and/or steam in the reactor KCHO 100, carbon monoxide can react with water and/or steam to form carbon dioxide and hydrogen through a water gas shift (WGS) reaction, for example, as represented by equation (4):

CO + H ₂ O θ CO ₂ + H ₂ (4)

The WGS reaction can increase the H2/CO molar ratio in the synthesis gas 15.

When carbon is present in the reactor (for example, coke; C produced by the decomposition reaction represented by equation (2)), dilute water and/or steam can react with the carbon and produce additional amounts of CO and H2, for example, as represented by equation ( 5):

C+H ₂ O θ CO+H ₂ (5)

In addition, since oxygen is present in the reactant mixture of KCHO 10, carbon present in the reactor (for example, coke; C produced by the decomposition reaction represented by equation (2)) can also react with oxygen, for example, as represented by equation (6 ):

C+O ₂ CO ₂ (6)

As will be appreciated by one skilled in the art and by reference to this description, although the chemical reactions represented by Equations (5) and (6) may consume the first portion of carbon produced in the CPO reactor, the second portion of carbon may be deposited as coke on a KCHO catalyst.

Additionally, CO2 can react with carbon (such as coke; C produced by the decomposition reaction represented by equation (2)), for example, as represented by equation (7):

C+CO ₂ o 2CO (7), thereby reducing the amount of coke deposited on the CCHO catalyst. As will be appreciated by one skilled in the art and by reference to this description, although the reactions represented by equations (4) and (6) may produce CO2 in the CPO reactor 100, such CO2 may not completely prevent coke deposition on the CPO catalyst due in part to for CO ₂ participating in reactions other than the reaction represented by equation (7).

For example, CO ₂ can react with methane in a dry reforming reaction, for example, as represented by equation (8):

CH4+CO2 o 2СО+2Н ₂ (8), thereby increasing the amount of CO and H2 in the resulting synthesis gas (for example, synthesis gas 15). Without intending to be bound by any theory, it should be noted that the dry reforming reaction (eg, represented by equation (8)) is an endothermic reaction. Dry reforming can remove some of the process heat (eg, heat from an exothermic CPO reaction, such as that represented by equation (1)).

In one aspect, the CPO reactor 100 can be operated under near-isothermal conditions, where the near-isothermal conditions include a temperature change of less than approximately ±100°C throughout the CPO reactor and/or its catalyst bed, where the catalyst bed contains the CPO catalyst, and where one reaction the zone contains a catalyst layer. In one aspect, the CPO reactor 100 can be operated under isothermal conditions, where the isothermal conditions include a temperature change of approximately less than ±10°C throughout the CPO reactor and/or its catalyst bed, where the catalyst bed contains the CPO catalyst, and where one reaction zone contains catalyst layer. In some aspects, near isothermal conditions and/or isothermal conditions can be achieved by removing process heat from the CPO reactor 100. In such aspects, removing heat from the CPO reactor 100 may include removing heat through an endothermic dry reforming reaction (e.g., represented by equation (8) ) between carbon dioxide and methane.

In one aspect, the CPO reactor 100 can be operated at a molar ratio of steam to carbon (S/C) in the CPO reactant mixture of less than about 2.4:1, or less than about 2:1, or less than about 1.5 :1, or less than about 1:1, or less than about 0.8:1, or about 0.01:1 to less than 2.4:1, or about 0.05:1 to 2:1, or from approximately 0.1:1 to 1.5:1, or from approximately 0.15:1 to 1:1 or, on the other hand, from approximately 0.2:1 to 0, 8:1, where the P/C molar ratio means the total moles of water (H2O) in the reactant mixture divided by the total moles of carbon (C) hydrocarbons in the reactant mixture. As will be appreciated by one skilled in the art and by reference to this description, the water vapor that is introduced into the reactor for use as a diluent in the CPO reaction disclosed in the invention is present in significantly smaller quantities than the water vapor used in steam reforming processes (e.g., SRP), and as such, the synthesis gas production process disclosed herein can produce synthesis gas with lower amounts of hydrogen compared to the amounts of hydrogen in synthesis gas produced by steam reforming .

The P/S molar ratio of the CPO reactant mixture 10 can be adjusted based on the desired CPO effluent temperature (eg, the target CPO effluent temperature) to increase (eg, maximize) the H2 content of the resulting synthesis gas. As will be appreciated by one skilled in the art and from this description, reaction (3) which consumes water vapor in the CPO 100 reactor is preferred over the water gas shift (WGS) reaction (4) in the CPO 100 reactor. since reaction (3) increases the H2 content of the resulting synthesis gas as well as the M ratio of the resulting synthesis gas, where the M ratio is a molar ratio defined as (H2-CO2)/(CO +CO2).

In one aspect, the amount of methane that reacts according to reaction (3) in the CPO 100 reactor is less than the amount of methane that reacts according to reaction (1) in the CPO 100 reactor. In one aspect, it is less than about 50 mol.%, or about less than 40 mol.%, or approximately less than 30 mol.%, or less than approximately 20 mol.%, or less than approximately 10 mol.% hydrocarbons (for example, methane) react with water vapor in the KCHO 100 reactor.

Without intending to be bound by any theory, it is believed that the presence of water and/or steam in the KCHO 100 reactor changes the flammability of the KCHO 10 reactant mixture, thereby providing a wider practical range of C/O molar ratios in the KCHO 10 reactant mixture. In addition, It is believed, without intending to be bound by theory, that the presence of water and/or steam in the KCHO 100 reactor allows the use of lower C/O molar ratios in the KCHO 10 reactant mixture. Moreover, without intending to be bound by any theory, it is believed that that the presence of water and/or water vapor in the KChO 100 reactor allows the KChO 100 reactor to be operated at relatively high pressures.

As will be appreciated by one skilled in the art and from this description, the introduction of water and/or steam into the CPO reactor 100 may result in an increase in the amount of unreacted hydrocarbons in the synthesis gas 15. Additionally, as will be appreciated by one skilled in the art technology, and by this description, methanol production processes typically allow limited amounts of unreacted hydrocarbons in the synthesis gas.

In some aspects, synthesis gas 15 may contain less than about 7.5 mole%, or less than about 5 mole%, or, alternatively, less than about 2.5 mole% hydrocarbons (e.g., unreacted hydrocarbons , unreacted CH ₄ ). In such aspects, synthesis gas 15 can be produced in a CPO process that uses water and/or steam. In such aspects, synthesis gas 15 can be used to synthesize methanol.

In one aspect, synthesis gas 15 may have a CO2 content of less than about 5 mole%, or less than about 4 mole%, or less than about 3 mole%, or less than about 2 mole%, or or about less than 1 mol.%, or about 0.1 to 5 mol.%, or about 0.25 to 4 mol.%, or, on the other hand, about 0.5 to 3 mol.% % Synthesis gas 15 advantageously can be produced with a CO2 content of less than about 5 mol.%, although CO ₂ (for example, CO2 stream 13) is introduced into the reactor 100. The rather low CO2 content of synthesis gas 15 may result in a crude stream methanol 40 having a fairly low water content (for example, less than about 10 wt.%, or less than about 8 wt.%, or less than about 6 wt.%, or less than about 4 wt.%, or less than about 3 wt.%, or less than about 2 wt.%, or, on the other hand, less than about 1 wt.% based on the total weight of the crude methanol stream 40). The benefits of a fairly low CO2 content in the synthesis gas 15 and/or a fairly low water content in the crude methanol stream 40 are described in more detail in co-pending U.S. Provisional Patent Application No. 62/794,783, filed Jan. 21, 2019, entitled Methanol Production Process, and No. 62/787598, filed Jan. 2, 2019, entitled Methanol Production Process, each of which is incorporated herein by reference in its entirety.

In one aspect, synthesis gas 15 can be recovered from CPO reactor 100, wherein synthesis gas 15 contains hydrogen, carbon monoxide, water, carbon dioxide, and unreacted hydrocarbons.

In some aspects, synthesis gas 15 (for example, after cooling and removing water from the synthesis gas and/or after adjusting the pressure and/or temperature of the synthesis gas) can be used in a downstream process (for example, in the production of methanol) without further processing to increasing the hydrogen content of the synthesis gas 15 (eg, the synthesis gas 15 is not further processed to increase the hydrogen content). The synthesis gas 15 disclosed in the invention may have a H ₂ /CO molar ratio of greater than about 1.7, or greater than about 1.8, or greater than about 1.9, or greater than about 2. 0, or approximately 10 044090 greater than 2.1. In some aspects, synthesis gas 15 disclosed herein can be characterized by an H ₂ /CO molar ratio of about 1.7 to 2.3, or about

1.8 to 2.2 or, on the other hand, approximately 1.9 to 2.1.

In one aspect, the synthesis gas 15 can be characterized by a molar ratio M of from about 1.2 to 1.8, or from about 1.6 to 1.78, or, on the other hand, from about 1.7 to 1.78, where the ratio M is a molar ratio defined as (H ₂ -CO ₂ )/(CO+CO ₂ ).

In other aspects, the synthesis gas 15 may be further processed before using the synthesis gas 15 in a downstream process, such as methanol production. Synthesis gas 15 may be processed to enrich it in hydrogen content, for example, by contacting synthesis gas 15 with additional (eg, makeup) hydrogen (eg, hydrogen stream 51).

As will be appreciated by one skilled in the art and by reference to this description, although synthesis gas 15 may be characterized by a H2/CO molar ratio greater than about 1.8, which may be acceptable for methanol synthesis, synthesis gas 15 may be Redesigned to further increase hydrogen content. In addition, as one skilled in the art will appreciate and with the benefit of this description, synthesis gas 15 can be subjected to minimal processing, such as recovery of unreacted hydrocarbons, diluent, water, etc., without significantly changing the H2/CO molar ratio synthesis gas KCHO 15. For example, water can be condensed and separated from the synthesis gas 15, for example, in a condenser.

In one aspect, the methanol production method described in the invention may further comprise (i) recovering at least a portion of the unreacted hydrocarbons from the synthesis gas 15 to produce recovered hydrocarbons, and (ii) recycling at least a portion of the recovered hydrocarbons to the CPR reactor 100. As will be appreciated by one skilled in the art and with the benefit of this description, although fairly high conversions can be achieved in CPR processes (e.g., conversions equal to or greater than approximately 90%), unreacted hydrocarbons can be recovered and recycled back to the reactor KCHO 100.

In aspects where synthesis gas 15 has an M ratio of about 1.8 to 2.2, synthesis gas 15 can also be used to produce methanol.

In one aspect, a method for producing methanol disclosed herein may include the step of introducing at least a portion of the synthesis gas 15 into a methanol reactor 200 to produce a methanol reactor effluent 30; wherein the effluent stream of methanol reactor 30 contains methanol, water, hydrogen, carbon monoxide, carbon dioxide and hydrocarbons. The methanol reactor 200 may be any reactor suitable for the synthesis reaction of methanol from CO and H ₂ , such as, for example, an isothermal reactor, an adiabatic reactor, a thin trickle bed reactor, a fluidized bed reactor, a slurry reactor, a loop reactor, etc. etc., cooled multi-tube reactor, etc., or combinations thereof.

Typically, CO and H2 can be converted to methanol (CH ₃ OH), for example, as represented by equation (9):

CO+H ₂ o CH ₃ OH (9)

Also CO2 and _H2 can also be converted into methanol, for example, as represented by equation (10):

CO ₂ + ZN ₂ θ CH ₃ OH + H ₂ O (10)

The synthesis of methanol from CO, CO ₂ and H ₂ is a catalytic process and is most often carried out in the presence of copper-based catalysts. Methanol reactor 200 may contain a catalyst for the production of methanol, such as any suitable commercial catalyst used for the synthesis of methanol.

Non-limiting examples of methanol production catalysts suitable for use in the methanol reactor 200 in the present invention include Cu, Cu/ZnO, Cu/ThO ₂ , Cu/Zn/Al ₂ O ₃ , Cu/ZnO/Al ₂ O ₃ , Cu/ Zr, etc., or combinations thereof.

In one aspect, a method for producing methanol disclosed herein may include the step of separating at least a portion of the effluent stream of methanol reactor 30 into a crude methanol stream 40 and a steam stream 50; wherein the crude methanol stream 40 contains methanol and water; wherein the steam stream 50 contains hydrogen, carbon monoxide, carbon dioxide and hydrocarbons. The effluent stream of methanol reactor 30 may be separated into a crude methanol stream 40 and a vapor stream 50 in a gas-liquid separator 300, such as a vapor-liquid separator, a flash drum, a gas separator, a condensate collector, a compressor suction separator, etc.

In one aspect, the crude methanol stream 40 may contain water in an amount of less than about 10 wt.%, or less than about 8 wt.%, or less than about 6 wt.%, or less than about 4 wt.%, or less than about 3 wt.%, or less than about 2 wt.%, or, on the other hand, less than about 1 wt.% based on the total weight of the crude methanol stream 40.

In one aspect, the crude methanol stream 40 may contain methanol in an amount equal to or greater than about 90 weight percent, or equal to or greater than about 92 weight percent, or

- 11 044090 equal to or greater than approximately 94% by weight, or equal to or greater than approximately 96% by weight, or equal to or approximately greater than 97% by weight, or equal to or approximately greater than 98% by weight or, on the other hand, equal to or greater than about 99 wt.% of the total mass of the crude methanol stream 40.

In one aspect, a method for producing methanol disclosed herein may include the step of separating at least a portion of a crude methanol stream 40 in a distillation unit 400 into a methanol stream 45 and a water stream 46, wherein the distillation unit 400 includes one or more distillation columns. Water stream 46 contains water and residual methanol. Typically, one or more distillation columns may separate components of the crude methanol stream 40 based on their boiling points.

In one aspect, methanol stream 45 may contain methanol in an amount equal to or greater than about 95 weight percent, or equal to or greater than about 97.5 weight percent, or equal to or greater than about 99 weight percent, or, with on the other hand, equal to or greater than about 99.9 wt.% based on the total weight of the methanol stream 45.

In one aspect, a method for producing methanol disclosed herein may include the step of separating at least a portion of the steam stream 50 into a hydrogen stream 51 and a tail gas stream 52, wherein the hydrogen stream 51 contains at least a portion of the hydrogen of the steam stream 50, wherein the tail gas stream gas 52 contains carbon monoxide, carbon dioxide and hydrocarbons. The steam stream 50 may be divided into a hydrogen stream 51 and a residual gas stream 52 in a hydrogen recovery unit 500, such as a PSA unit, a membrane separation unit, a cryogenic separation unit, and the like, or combinations thereof.

In one aspect, at least a portion 51a of the hydrogen stream 51 may be recycled to the methanol reactor 200, for example, via synthesis gas 15.

In one aspect, the methanol production method described in the invention may include the step of separating at least a portion of the tail gas stream 52 in a CO ₂ separator 600 (eg, a CO ₂ scrubber) into a CO 2 stream 13 and a purge gas stream 60; wherein the CO2 stream 13 contains at least a portion of the CO ₂ tail gas stream 52; and wherein the purge gas stream 60 contains carbon monoxide and hydrocarbons.

The CO2 separator 600 may include CO2 removal by amine (e.g. monoethanolamine) absorption (e.g. amine scrubbing), pressure swing adsorption (PSA), temperature swing adsorption, gas separation membranes (e.g. porous inorganic membranes, palladium membranes, polymer membranes, zeolites, etc.), using cryogenic separation, etc., or combinations thereof. In one aspect, the CO2 separator 600 may include removing CO2 by amine absorption. As will be appreciated by one skilled in the art, and from this description, CO2-depleted synthesis gas has a higher M ratio than CO2-rich synthesis gas, since the lower the CO2 content of the synthesis gas, the higher M ratio of synthesis gas.

In some aspects, at least a portion of the purge gas stream 60 may be removed. In other aspects, at least a portion of the purge gas stream 60 may be used as a fuel, for example, to preheat the reactant mixture of the CCO 10.

In one aspect, at least a portion of the CO ₂ stream 13 can be recycled to the CPO reactor 100, for example, after adjusting the temperature and/or pressure of the CO 2 stream 13 to desired values. CO2 introduced into the CPO reactor via the CO2 stream 13 may provide CO2, which can further reduce or eliminate coke deposits on the CPO catalysts, for example, by participating in the reaction represented by equation (7). In one aspect, the amount of carbon deposited on the CPO catalyst may be less than the amount of carbon deposited on the catalyst in an otherwise similar process in which the CO2 stream is not recycled to the CPO reactor.

In addition, CO2 introduced into the reactor CPO 100 via the CO2 stream 13 may provide CO2, which can be converted into useful synthesis gas components such as CO and _H2 , for example, by participating in the dry reforming reaction represented by equation ( 8).

As will be appreciated by one skilled in the art and from this description, the reactions represented by equations (7) and (8) reduce the amount of CO ₂ that will be present in the synthesis gas 15. Moreover, as will be appreciated by one skilled in the art In the art, and through this description and without intending to be bound by any theory, the H ₂ /CO molar ratio of synthesis gas takes into account the amounts of hydrogen and CO present in the synthesis gas; in this case, the M ratio of the synthesis gas takes into account the dioxide content in the synthesis gas, in addition to the amounts of hydrogen and CO present in the synthesis gas.

In one aspect, a method for producing methanol may include the steps of (a) reacting, through a catalytic partial oxidation (CPO) reaction, a mixture of CPO reactants 10 in a CPO reactor 100 to produce synthesis gas 15; where the mixture of reagents KCHO 10 contains hydrocarbons and oxygen; where the KChO reactor 100 contains the KChO catalyst; and wherein the synthesis gas 15 contains hydrogen (H2), carbon monoxide (CO), carbon dioxide ( _CO2 ), water (H2O) and unreacted hydrocarbons; (b) cooling at least a portion of the synthesis gas 15 to produce cooled synthesis gas and process heat (eg, which can be recovered and used as thermal energy); (c) removing at least a portion of the water from the cooled synthesis gas to produce dehydrated synthesis gas, wherein the dehydrated synthesis gas contains H2, CO, CO2 and unreacted hydrocarbons; (d) introducing at least a portion of the dehydrated synthesis gas into methanol reactor 200 to form an effluent stream of methanol reactor 30; wherein the effluent stream of methanol reactor 30 contains methanol, water, hydrogen, carbon monoxide, carbon dioxide and hydrocarbons; (e) separating at least a portion of the effluent stream of methanol reactor 30 in gas-liquid separator 300 into a crude methanol stream 40 and a steam stream 50, wherein the steam stream 50 contains hydrogen, carbon monoxide, carbon dioxide, and hydrocarbons; (f) separating at least a portion of the steam stream 50 into a hydrogen stream 51 and a residual gas stream 52; wherein the hydrogen stream 51 contains at least a portion of the hydrogen of the steam stream 50; and wherein the residual gas stream 52 contains carbon monoxide, carbon dioxide and hydrocarbons; (g) separating at least a portion of the residual gas stream 52 in the CO2 separator 600 into a CO2 stream 13 and a purge gas stream 60; wherein the CO2 stream 13 contains at least a CO2 portion of the tail gas stream 52; (h) recycling at least a portion of the CO ₂ stream 13 to the KCHO reactor 100; and (i) recycling at least a portion of the hydrogen stream 51 to the methanol reactor 200. In such an aspect, the CPO reactor 100 may be characterized by a nearly isothermal temperature.

In one aspect, the methanol production method described in the invention may advantageously exhibit improvements in one or more process characteristics compared to an otherwise similar process in which the CO ₂ stream is not recycled to the CPO reactor. The methanol production method disclosed in the invention may advantageously demonstrate a reduction in coke (eg, carbon) deposits in the CPO reactor, eg, coke deposits on the CPO catalyst. Part of the CO2 stream recycled into the CPO reactor may preferentially react with coke deposits. As will be appreciated by one of ordinary skill in the art and from this description, reduced coke deposits on the CPO catalyst can advantageously increase the life and performance of the catalyst.

In one aspect, a portion of the CO2 stream recycled to the CPO reactor may advantageously react with methane through a dry reforming reaction, resulting in near-isothermal operation of the CPO reactor.

As will be appreciated by one skilled in the art and from this description, since the CPO reaction is exothermic, no additional heat input in the form of combustion of fuel is required (other than preheating the reactants in the reaction mixture, which is supplied to the synthesis gas production site ) compared to conventional steam reforming. Thus, the method described in the invention for producing synthesis gas can advantageously generate less CO2 by burning fuel compared to steam reforming.

In one aspect, the methanol production process described in the invention can advantageously provide improved overall carbon utilization (eg, carbon efficiency) when compared to an otherwise similar process in which the CO2 stream is not recycled to the CPR reactor. As used herein, carbon efficiency is defined as the ratio of the number of moles of carbon present in the methanol stream (eg, methanol stream 45) to the number of moles of carbon in the CPO reactant mixture (eg, CPO 10 reactant mixture). Additional advantages of the methanol production methods described herein may be apparent to one skilled in the art considering the present invention.

For the purposes of filing this application nationally in the United States, all publications and patents mentioned in this specification are hereby incorporated by reference in their entirety to describe and disclose the designs and methodologies described in these publications that may be used in connection with the methods of this invention. Any publications and patents discussed herein are provided solely for their disclosure prior to the filing date of this application. Nothing herein should be construed as recognizing that inventors are not entitled to backdate such disclosure based on a prior invention.

Any application filed with the United States Patent and Trademark Office shall provide an abstract of that application to satisfy the requirements of 37 CFR § 1.72 and the purpose of 37 CFR § 1.72(b) to enable the United States Patent and Trademark Office and the public In general, quickly determine, based on a quick review, the nature and essence of the technical disclosure. Accordingly, the abstract of this application is not intended to be used in interpreting the scope of the claims or to limit the scope of the subject matter disclosed herein.

Moreover, any headings that may be used herein are also not intended to be used to construe the scope of the claims or to limit the scope of the subject matter disclosed herein. Any use of the past tense to describe an example otherwise designated as constructive or prophetic is not intended to reflect that the constructive or prophetic example was actually brought to pass.

Additional Description

The following are non-limiting specific embodiments in accordance with the present invention.

- 13 044090

The first embodiment, which is a method for producing methanol, comprising (a) reacting, through a catalytic partial oxidation (CPO) reaction, a mixture of CPO reactants in a CPO reactor to produce synthesis gas, wherein the mixture of CPO reactants contains hydrocarbons, oxygen, and optionally water vapor; wherein the CPO reactor contains one reaction zone, wherein one reaction zone contains the CPO catalyst, and where the synthesis gas contains hydrogen (H2), carbon monoxide (CO), carbon dioxide (CO2), water (H2O) and unreacted hydrocarbons, (b) introducing at least a portion of the synthesis gas into a methanol reactor to produce a methanol reactor effluent stream, wherein the methanol reactor effluent stream contains methanol, water, hydrogen, carbon monoxide, carbon dioxide and hydrocarbons, (c) separating at least a portion of the methanol reactor effluent stream into a crude methanol stream, a hydrogen stream, a CO2 stream and a purge gas stream; wherein the crude methanol stream comprises methanol and water, wherein the purge gas stream comprises carbon monoxide and hydrocarbons, and wherein the CO2 stream comprises at least a portion of the CO2 effluent stream of the methanol reactor, and (d) recycling at least a portion of the CO2 stream to the CPO reactor.

A second embodiment, which is a method of the first embodiment, wherein step (c) further includes separating at least a portion of the methanol reactor effluent stream in the gas-liquid separator into a crude methanol stream and a steam stream, wherein the steam stream contains hydrogen, carbon monoxide, dioxide carbons and hydrocarbons.

A third embodiment, which is a method of the second embodiment, further comprising separating at least a portion of the steam stream in the hydrogen recovery unit into a hydrogen stream and a tail gas stream, wherein the hydrogen stream contains at least a portion of the hydrogen of the steam stream, and where the tail gas stream contains carbon monoxide, carbon dioxide and hydrocarbons.

A fourth embodiment, which is a method of the third embodiment, further comprising separating at least a portion of the CO2 separator residual gas stream into a CO2 stream and a purge gas stream, wherein the CO2 stream contains at least a CO2 portion of the residual gas stream.

A fifth embodiment, which is a method of the fourth embodiment, in which the CO ₂ separator includes CO ₂ removal by amine absorption, pressure swing adsorption, temperature swing adsorption, gas separation membranes, cryogenic separation, or combinations thereof.

A sixth embodiment, which is a method of any of the first to fifth embodiments, including recycling at least a portion of the hydrogen stream to the methanol reactor.

A seventh embodiment, which is a method of any of the first to sixth embodiments, in which the hydrocarbons comprise methane, natural gas, liquefied natural gas, petroleum field gas, associated gas, rich gas, paraffins, shale gas, shale liquids, waste gas fluid - catalytic cracking (FCC), process gases from oil refining, flue gases, fuel gas from the fuel gas manifold, or combinations thereof.

The eighth embodiment, which is a method of any of the first to seventh embodiments, which includes (1) cooling at least a portion of the synthesis gas to obtain cooled synthesis gas; (2) removing at least a portion of the water from the cooled synthesis gas to obtain dehydrated synthesis gas, wherein the dehydrated synthesis gas contains H ₂ , CO, CO 2 and unreacted hydrocarbons; and (3) introducing at least a portion of the dehydrated synthesis gas into the methanol reactor in step (b).

The ninth embodiment, which is a method of any of the first to eighth embodiments, in which a portion of the hydrocarbons in the mixture of CPO reagents is decomposed to carbon and hydrogen.

The tenth embodiment, which is a method of the ninth embodiment, in which at least a portion of the carbon reacts with carbon dioxide in the CPO reactor to form carbon monoxide.

An eleventh embodiment, which is a method of any of the ninth and tenth embodiments, in which a portion of the carbon is deposited on the CPO catalyst, and wherein the amount of carbon deposited on the CPO catalyst is less than the amount of carbon deposited on the catalyst, otherwise similar a method in which the CO ₂ stream is not recycled into the CPO reactor.

The twelfth embodiment, which is a method of any of the first to eleventh embodiments, in which a portion of the hydrocarbons is reacted with carbon dioxide in a CPO reactor through a dry reforming reaction to produce hydrogen and carbon monoxide.

A thirteenth embodiment, which is a method of any of the first to twelfth embodiments, wherein the CPO reactor is characterized by at least one CPO operating parameter selected from the group consisting of a CPO feed temperature of about 25 to 600° C.; the temperature of the CCHO outlet stream is approximately from 300 to 1600°C; pressure

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COC from approximately 1 to 90 bar(g); CCO contact time is approximately from 0.001 milliseconds (ms) to 5 s; the molar ratio of carbon to oxygen (C/O) in a mixture of COC reagents is approximately 0.5:1 to 3:1, where the molar ratio C/O means the total number of moles of carbon (C) hydrocarbons in the mixture of reagents divided by the total number of moles oxygen (O2) in a mixture of reagents; the molar ratio of water vapor to carbon (V/C) in the CWC reactant mixture is from approximately 0.01:1 to less than 2.4:1, where the molar ratio (V/C) means the total number of moles of water (H2O) in the reactant mixture , divided by the total number of moles of carbon (C) hydrocarbons in the reactant mixture; and their combinations.

A fourteenth embodiment, which is a method of any of the first to thirteenth embodiments, wherein the CPO reactor is operated under near-isothermal conditions, wherein the near-isothermal conditions include a temperature variation of approximately less than ±100°C throughout the CPO reactor and/or its catalyst bed , where the catalyst bed contains the CPO catalyst, and where one reaction zone contains the catalyst bed.

The fifteenth embodiment, which is the method of the fourteenth embodiment, in which near isothermal conditions are provided by removing process heat from the CPO reactor.

The sixteenth embodiment, which is a method of the fifteenth embodiment, in which the heat removal includes heat removal through an endothermic dry reforming reaction between carbon dioxide and methane.

A seventeenth embodiment, which is a method for producing methanol, comprising (a) reacting, through a catalytic partial oxidation (CPO) reaction, a mixture of CPO reagents in a CPO reactor to produce synthesis gas, wherein the mixture of CPO reagents contains hydrocarbons and oxygen, wherein the CPO reactor contains one a reaction zone, wherein one reaction zone contains a CPO catalyst, and wherein the synthesis gas contains hydrogen (H2), carbon monoxide (CO), carbon dioxide (CO2), water (H2O) and unreacted hydrocarbons, (b) cooling at least a portion synthesis gas 15 to produce cooled synthesis gas, (c) removing at least a portion of the water from the cooled synthesis gas to produce dehydrated synthesis gas, wherein the dehydrated synthesis gas contains H2, CO, CO2 and unreacted hydrocarbons, (d) introducing at least a portion of the dehydrated synthesis gas to a methanol reactor to produce a methanol reactor effluent stream, wherein the methanol reactor effluent stream contains methanol, water, hydrogen, carbon monoxide, carbon dioxide, and hydrocarbons, (e) separating at least a portion of the methanol reactor effluent stream in a gas-liquid separator into a crude methanol stream and a steam stream, where the steam stream contains hydrogen, carbon monoxide, carbon dioxide and hydrocarbons, (f) separating at least a portion of the steam stream into a hydrogen stream and a tail gas stream, where the hydrogen stream contains at least a hydrogen portion of the steam stream, and wherein the tail gas stream contains carbon monoxide, carbon dioxide and hydrocarbons, (g) separating at least a portion of the tail gas stream in the CO2 separator into a CO2 stream and a purge gas stream, wherein the CO2 stream contains at least a portion of the CO2 a tail gas stream, (h) recycling at least a portion of the CO2 stream to the CPO reactor, and (i) recycling at least a portion of the hydrogen stream to the methanol reactor.

The eighteenth embodiment, which is the method of the seventeenth embodiment, in which at least a portion of the purge gas stream is used as fuel.

A nineteenth embodiment, which is a method of the eighteenth embodiment, wherein at least a portion of the fuel is used to preheat at least a portion of the CPO reactant mixture before introducing the CPO reactant mixture into the CPO reactor.

A twentieth embodiment, which is a method of any of the seventeenth to nineteenth embodiments, wherein the CPO reactor is operated under near-isothermal conditions, wherein the near-isothermal conditions include a temperature change of approximately less than ±100°C throughout the CPO reactor and/or a bed thereof catalyst, where the catalyst layer contains the CPO catalyst, and where one reaction zone contains the catalyst layer.

While embodiments of the invention have been presented and described, modifications may be made without departing from the spirit and ideas of the invention. The embodiments and examples described herein are illustrative only and are not intended to be limiting. Many variations and modifications of the disclosed invention are possible and are within the scope of the invention.

Accordingly, the scope of protection is not limited by the above description, but is limited only by the claims below, which scope includes all equivalents of the subject matter of the claims. Each claim is included in the description as an embodiment of the present invention. Thus, the claims are intended to further describe and supplement the detailed description of the present invention. The descriptions of all patents, patent applications and publications cited herein are incorporated herein by reference.

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Claims (15)

CLAIM 1. A method for producing methanol, including (a) interaction through a catalytic partial oxidation (CPO) reaction of a mixture of CPO reagents in a CPO reactor to produce synthesis gas, where the mixture of CPO reagents contains hydrocarbons and oxygen, where the CPO reactor contains one reaction zone, and one the reaction zone contains the CPO catalyst, and where the synthesis gas contains hydrogen (H2), carbon monoxide (CO), carbon dioxide (CO2), water (H2O) and unreacted hydrocarbons; (b) introducing at least a portion of the synthesis gas into a methanol reactor to produce a methanol reactor effluent, wherein the methanol reactor effluent comprises methanol, water, hydrogen, carbon monoxide, carbon dioxide, and hydrocarbons; (c) separating at least a portion of the methanol reactor effluent stream into a crude methanol stream, a hydrogen stream, a CO2 stream, and a purge gas stream, wherein the crude methanol stream contains methanol and water, where the purge gas stream contains carbon monoxide and hydrocarbons, and where the CO2 stream contains at least a portion of the CO2 effluent of the methanol reactor; and (d) recycling at least a portion of the CO2 stream to the CPO reactor. 2. The method according to claim 1, in which the mixture of CPO reagents optionally contains water vapor. 3. The method of claim 1, wherein step (c) further comprises separating at least a portion of the methanol reactor effluent stream in the gas-liquid separator into a crude methanol stream and a steam stream, wherein the steam stream contains hydrogen, carbon monoxide, carbon dioxide and hydrocarbons. 4. The method of claim 3, further comprising separating at least a portion of the steam stream in the hydrogen recovery unit into a hydrogen stream and a residual gas stream, wherein the hydrogen stream contains at least a portion of the hydrogen of the steam stream and wherein the residual gas stream contains carbon monoxide, dioxide carbons and hydrocarbons. 5. The method of claim 4, further comprising separating at least a portion of the CO2 separator tail gas stream into a CO2 stream and a purge gas stream, wherein the CO2 stream comprises at least a CO ₂ portion of the tail gas stream. 6. The method of claim 5, wherein the CO2 separator comprises CO2 removal by amine absorption, pressure swing adsorption, temperature swing adsorption, gas separation membranes, cryogenic separation, or combinations thereof. 7. The method of claim 1, further comprising recycling at least a portion of the hydrogen stream to the methanol reactor. 8. The method according to claim 1, in which the hydrocarbons contain methane, natural gas, liquefied natural gas, petroleum field gas, associated gas, enriched gas, paraffins, shale gas, shale liquids, fluid catalytic cracking waste gas (FCC) ), refinery process gases, flue gases, fuel gas from a fuel gas manifold, or combinations thereof. 9. The method of claim 1, wherein the method includes (1) cooling at least a portion of the synthesis gas to produce cooled synthesis gas; (2) removing at least a portion of the water from the cooled synthesis gas to obtain dehydrated synthesis gas, wherein the dehydrated synthesis gas contains H ₂ , CO, CO 2 and unreacted hydrocarbons; and (3) introducing at least a portion of the dehydrated synthesis gas into the methanol reactor in step (b). 10. The method according to claim 1, in which part of the hydrocarbons in the mixture of CCHO reagents undergoes decomposition to carbon and hydrogen. 11. The method of claim 10, wherein at least a portion of the carbon reacts with carbon dioxide in the CPO reactor to form carbon monoxide. 12. The method of claim 10, wherein carbon is deposited on the CPO catalyst, and wherein the amount of carbon deposited on the CPO catalyst is less than the amount of carbon deposited on the catalyst in an otherwise similar process in which the CO2 stream is not recycled to KChO reactor. 13. The method according to claim 1, in which part of the hydrocarbons reacts with carbon dioxide in the CPO reactor through a dry reforming reaction to form hydrogen and carbon monoxide. 14. The method according to claim 1, in which the reactor is characterized by at least one operating parameter of the reactor, selected from the group consisting of a feed temperature of the reactor from approximately 25 to 600°C; the temperature of the CCHO outlet stream is approximately from 300 to 1600°C; ECC pressure from approximately 1 to 90 bar(g); CCO contact time is approximately from 0.001 milliseconds (ms) to 5 s; the molar ratio of carbon to oxygen (C/O) in a mixture of COC reagents is approximately 0.5:1 to 3:1, where the molar ratio C/O means the total number of moles of carbon (C) hydrocarbons in the mixture of reagents divided by the total number of moles oxygen (O2) in the mixture of reagents; the molar ratio of water vapor to carbon (P/C) in the CWC reactant mixture is from approximately 0.01:1 to less than 2.4:1, where the molar ratio (P/C) means the total number of moles of water (H2O) in the reactant mixture , divided by the total number of moles of carbon (C) hydrocarbons in the reactant mixture; and their combinations. 15. The method of claim 1, wherein the CPO reactor is operated under near-isothermal conditions, wherein the near-isothermal conditions include a temperature change of approximately less than ±100°C -