Preparation method of mixed alkyl ketone and alkyl alcohol

Abstract

The invention provides a preparation method of mixed alkyl ketone and alkyl alcohol, and relates to the technical field of chemical engineering. The preparation method comprises the following steps: mixing mineral oil, liquid paraffin and a catalyst to form a reactant; conveying the reactant into a reaction module of the micro-channel reactor, introducing oxidizing gas into the reaction module, and enabling the oxidizing gas and the reactant to react for a preset time length at a preset temperature to form an intermediate product; and removing the catalyst in the intermediate product to form a target product, and adding an alkaline solvent into the target product to obtain the mixed alkyl ketone and alkyl alcohol. The preparation method disclosed by the invention can improve the production safety.

Description

Technical Field

[0001] The present disclosure relates to the technical field of chemical engineering, and more particularly, to a method for preparing a mixed alkyl ketone and an alkyl alcohol. Background Art

[0002] The mixed alkyl ketone and alkyl alcohol are important fine chemical intermediates. Through further processing, alkyl acids or alcohols can be obtained, which can be used as rust inhibitors, plasticizers, alcohol for detergents, etc. However, during the preparation process of alkyl ketones and alkyl alcohols, a large amount of heat is released, and risks such as explosion are likely to occur, resulting in a low safety factor.

[0003] It should be noted that the information disclosed in the above background art is only used to enhance the understanding of the background of the present disclosure, and thus may include information that does not constitute the prior art known to those of ordinary skill in the art. Summary of the Invention

[0004] The present disclosure provides a method for preparing a mixed alkyl ketone and an alkyl alcohol, which can improve production safety.

[0005] According to one aspect of the present disclosure, there is provided a method for preparing a mixed alkyl ketone and an alkyl alcohol, comprising:

[0006] Mixing mineral oil, liquid paraffin, and a catalyst to form a reactant;

[0007] Feeding the reactant into a reaction module of a microchannel reactor, and introducing an oxidizing gas into the reaction module. The oxidizing gas reacts with the reactant at a preset temperature for a preset duration to form an intermediate product;

[0008] Removing the catalyst from the intermediate product to form a target product;

[0009] Adding a basic solvent to the target product to obtain a mixed alkyl ketone and an alkyl alcohol.

[0010] In an exemplary embodiment of the present disclosure, the oxidizing gas includes oxygen and a diluting gas, and the diluting gas includes nitrogen, carbon dioxide, or ozone.

[0011] In an exemplary embodiment of the present disclosure, the catalyst includes one or more of zirconium oxide, yttrium oxide, cerium oxide, ethylene glycol, 1,3 - propanediol, 1,4 - butanediol, hexanediol, acetic anhydride, expanded graphite, β - zeolite, zinc chloride, iron chloride, cerium chloride, anhydrous boric acid, metaboric acid, boron trioxide, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium bicarbonate, potassium bicarbonate, ammonia, methylamine, ethylamine, dimethylamine, or diethylamine.

[0012] In an exemplary embodiment of the present disclosure, the preset temperature is 25°C to 170°C; the preset duration is 20 seconds to 180 seconds.

[0013] In an exemplary embodiment of the present disclosure, the reactant includes at least one of a straight-chain alkane having 8 to 20 carbon atoms, a branched-chain alkane having 8 to 20 carbon atoms, a cycloalkane having 6 to 18 carbon atoms, and a substituted cycloalkane having 6 to 18 carbon atoms.

[0014] In an exemplary embodiment of the present disclosure, the straight-chain alkane having 8 to 20 carbon atoms includes:

[0015] one or more of n-octane, n-nonane, n-decane, n-undecane, n-dodecane, n-tridecane, n-tetradecane, n-pentadecane, n-hexadecane, n-heptadecane, n-octadecane, n-nonadecane, and n-eicosane;

[0016] The branched-chain alkane having 8 to 20 carbon atoms includes:

[0017] one or more of 2-methylheptane, 3-methylheptane, 4-methylheptane, 2-methyloctane, 3-methyloctane, 4-methyloctane, 2,6-dimethylheptane, 3,5-dimethylheptane, 2-methylnonane, 3-methylnonane, 4-methylnonane, 5-methylnonane, 2,7-dimethyloctane, 2,6-dimethyloctane, 3,6-dimethyloctane, 2-methyldecane, 3-methyldecane, 4-methyldecane, 2,8-dimethylnonane, 2,7-dimethylnonane, 3,8-dimethyldecane, 5-ethyldecane, 2-methylundecane, 3-methylundecane, 4-methylundecane, 2-methyldodecane, 3-methyldodecane, 2,9-methylundecane, 6-ethylundecane, 3-methyltridecane, 5-ethyldodecane, 4-methyltetradecane, 5-methylpentadecane, 6-methylhexadecane, 3-methylheptadecane, 6-methyloctadecane, 5-methylnonadecane, or 2,2,4-trimethylpentane;

[0018] The cycloalkane and substituted cycloalkane having 6 to 18 carbon atoms include:

[0019] one or more of cyclohexane, methylcyclohexane, 1,3-dimethylcyclohexane, 1,2-dimethylcyclohexane, 1,4-dimethylcyclohexane, ethylcyclohexane, 1,2,4-trimethylcyclohexane, 1,2,5-trimethylcyclohexane, 1-methyl-3-ethylcyclohexane, decalin, 1-methyldecalin, 1-ethyldecalin, 1-n-propyl decalin, tetradecahydroanthracene, 9-methyltetradecahydroanthracene, 9-ethyltetradecahydroanthracene, 9-n-propyltetradecahydroanthracene, 9-n-butyltetradecahydroanthracene, and tetradecahydrophenanthrene.

[0020] In an exemplary embodiment of the present disclosure, the catalyst includes zirconia, yttria, ceria, expanded graphite, β-zeolite, zinc chloride, iron chloride, cerium chloride, boric anhydride, metaboric acid, boron trioxide, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium bicarbonate, and potassium bicarbonate, all of which are solid catalysts, and the mesh number of the catalyst particles in the solid catalyst is 80 mesh to 400 mesh.

[0021] In an exemplary embodiment of the present disclosure, the weight of the solid catalyst is 1% to 8% of the total weight of the reactants.

[0022] In an exemplary embodiment of the present disclosure, the oxygen content in the oxidizing gas is 5% to 100%.

[0023] In an exemplary embodiment of the present disclosure, the volume ratio of the oxidizing gas to the reactants is 3:1 to 20:1.

[0024] In the method for preparing mixed alkyl ketones and alkyl alcohols of the present disclosure, the oxidizing gas and the reactants can react in a microchannel reactor to generate intermediate products. During this process, due to the small space in the microchannel reactor, the amount of the oxidizing gas contained therein is relatively small. Therefore, a large amount of heat will not be generated during the reaction, the possibility of explosion during the preparation process is small, and the safety factor is high. At the same time, the addition of the catalyst can accelerate the reaction rate between the oxidizing gas and the reactants, making the production process more efficient. It helps to improve the production speed, increases the output, and provides strong technical support for the large-scale production of mixed alkyl ketones and alkyl alcohols.

[0025] It should be understood that the above general description and the following detailed description are only exemplary and explanatory, and cannot limit the present disclosure. Brief Description of the Drawings

[0026] The drawings here are incorporated into the specification and form a part of this specification, showing embodiments consistent with the present disclosure, and are used together with the specification to explain the principles of the present disclosure. Obviously, the drawings in the following description are only some embodiments of the present disclosure, and those of ordinary skill in the art can obtain other drawings based on these drawings without creative efforts.

[0027] Figure 1 It is a flowchart of the method for preparing mixed alkyl ketones and alkyl alcohols in the embodiments of the present disclosure. Detailed Embodiments

[0028] Example embodiments will now be described more fully with reference to the accompanying drawings. However, the example embodiments can be implemented in various forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided so that this application will be more complete and comprehensive, and will fully convey the concept of the example embodiments to those skilled in the art. The described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. In the following description, numerous specific details are provided to give a thorough understanding of the embodiments of this application.

[0029] The terms "the" and "said" are used to indicate the presence of one or more elements / components / etc.; the terms "comprising" and "having" are used to mean an open inclusion and mean that there may be additional elements / components / etc. in addition to the listed elements / components / etc.

[0030] The mixed alkyl ketones and alkyl alcohols can be further oxidized to obtain alkyl acids, which can be used as raw materials for rust inhibitors. Or they can be reduced to obtain the corresponding alcohols, which can be used in fields such as plasticizer alcohols and detergent alcohols. In traditional methods for synthesizing alkyl ketones and alkyl alcohols, introducing a functional group carbonyl or hydroxyl group onto a chemically inert alkane raw material has a very long reaction time, or relatively harsh reaction conditions, with low product conversion rates and low product selectivity.

[0031] Based on this, the present disclosure provides a method for preparing mixed alkyl ketones and alkyl alcohols. Figure 1 A flowchart showing the method for preparing the mixed alkyl ketones and alkyl alcohols of the present disclosure is shown. Please refer to Figure 1 As shown, the preparation method may include steps S110 - step S140, where:

[0032] Step S110, mixing mineral oil, liquid paraffin, and a catalyst to form a reactant;

[0033] Step S120, conveying the reactant into the reaction module of a microchannel reactor, and introducing an oxidizing gas into the reaction module. The oxidizing gas reacts with the reactant at a preset temperature for a preset duration to form an intermediate product;

[0034] Step S130, removing the catalyst from the intermediate product to form a target product;

[0035] Step S140, adding an alkaline solvent to the target product to obtain mixed alkyl ketones and alkyl alcohols.

[0036] The preparation method of the mixed alkyl ketones and alkyl alcohols of the present disclosure is such that an oxidizing gas and a reactant can react in a microchannel reactor to form an intermediate product. During this process, due to the relatively small space in the microchannel reactor, the amount of the oxidizing gas accommodated therein is relatively small. Therefore, a large amount of heat will not be generated during the reaction, the possibility of explosion during the preparation process is relatively small, and the safety factor is relatively high. At the same time, the addition of a catalyst can accelerate the reaction rate between the oxidizing gas and the reactant, making the production process more efficient. It helps to increase the production speed, improve the output, and provides strong technical support for the large-scale production of the mixed alkyl ketones and alkyl alcohols.

[0037] The following details each step and its specific details of the preparation method of the mixed alkyl ketones and alkyl alcohols of the present disclosure:

[0038] As Figure 1 shown, in step S110, a mineral oil, a liquid paraffin, and a catalyst are mixed to form a reactant.

[0039] The mineral oil can be a base oil refined from petroleum by methods such as physical distillation. Its main components can include straight-chain, branched-chain alkanes, and alkyl-substituted cycloalkanes, etc. The mineral oil can be a colorless and translucent oily liquid. The liquid paraffin, also known as white oil or paraffin oil, can be a paraffin product refined from petroleum, and its main component is straight-chain alkanes. The catalyst can include one or more of zirconium oxide, yttrium oxide, cerium oxide, ethylene glycol, 1,3-propanediol, 1,4-butanediol, hexanediol, acetic anhydride, expanded graphite, β-zeolite, zinc chloride, iron chloride, cerium chloride, anhydrous boric acid, metaboric acid, boron trioxide, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium bicarbonate, potassium bicarbonate, ammonia, methylamine, ethylamine, dimethylamine, or diethylamine. The mineral oil, the liquid paraffin, and the catalyst can be mixed at room temperature to form a reactant. For example, the mineral oil, the liquid paraffin, and the catalyst can be mixed in a microchannel reactor. For example, the microchannel reactor can include a premixing module, a preheating module, a reaction module, a gas-liquid separation module, and a collection module, and each module can be connected in sequence. In the present disclosure, the mineral oil, the liquid paraffin, and the catalyst can be respectively added into the premixing module of the microchannel reactor, and the mineral oil, the liquid paraffin, and the catalyst can be mixed through the premixing module to form a reactant.

[0040] The formed reactant can include at least one of straight-chain alkanes with 8-20 carbon atoms, branched-chain alkanes with 8-20 carbon atoms, cycloalkanes with 6-18 carbon atoms, and substituted cycloalkanes with 6-18 carbon atoms.

[0041] For example, the straight-chain alkanes with 8-20 carbon atoms can include n-octane (structural formula is ), n-nonane (structural formula is ), n-decane (structural formula is ) n-Undecane (structural formula is ) n-Dodecane (structural formula is ) n-Tridecane (structural formula is ) n-Tetradecane (structural formula is ) n-Pentadecane (structural formula is ) n-Hexadecane (structural formula is ) n-Heptadecane (structural formula is ) n-Octadecane (structural formula is ) n-Nonadecane (structural formula is ) and n-Eicosane (structural formula is ) or more than one of them.

[0042] Branched alkanes with 8 - 20 carbon atoms may include 2-Methylheptane (structural formula is ) 3-Methylheptane (structural formula is ) 4-Methylheptane (structural formula is ) 2-Methyloctane (structural formula is ) 3-Methyloctane (structural formula is ) 4-Methyloctane (structural formula is ) 2,6-Dimethylheptane (structural formula is ) 3,5-Dimethylheptane (structural formula is ) 2-Methylnonane (structural formula is ) 3-Methylnonane (structural formula is ) 4-Methylnonane (structural formula is ) 5-Methylnonane (structural formula is ) 2,7-Dimethyloctane (structural formula is ) 2,6-Dimethyloctane (structural formula is ) 3,6-Dimethyloctane (structural formula is ) 2-Methyldecane (structural formula is ) 3-Methyldecane (structural formula is ) 4-Methyldecane (structural formula is ) 2,8-Dimethylnonane (structural formula is ) 2,7-Dimethylnonane (structural formula is ) 3,8-Dimethyldecane (structural formula is ) 5-Ethyldecane (structural formula is ) 2-Methylundecane (structural formula is ) 3-Methylundecane (structural formula is ) 4-Methylundecane (structural formula is ) 2-Methyldodecane (structural formula is ), 3-methyldodecane (structural formula ), 2,9-dimethylundecane (structural formula ), 6-ethylundecane (structural formula ), 3-methyltridecane (structural formula ), 5-ethyldodecane (structural formula ), 4-methyltetradecane (structural formula ), 5-methylpentadecane (structural formula ), 6-methylhexadecane (structural formula ), 3-methylheptadecane (structural formula ), 6-methyloctadecane (structural formula ), or 5-methylnonadecane (structural formula ), or one or more thereof.

[0043] Cycloalkanes and substituted cycloalkanes having 6 to 18 carbon atoms may include cyclohexane (structural formula ), methylcyclohexane (structural formula ), 1,3-dimethylcyclohexane (structural formula ), 1,2-dimethylcyclohexane (structural formula ), 1,4-dimethylcyclohexane (structural formula ), ethylcyclohexane (structural formula ), 1,2,4-trimethylcyclohexane (structural formula ), 1,3,5-trimethylcyclohexane (structural formula ), 1-methyl-3-ethylcyclohexane (structural formula ), decalin (structural formula ), 1-methyldecalin (structural formula ), 1-ethyldecalin (structural formula ), 1-n-propyldecalin (structural formula ), tetradecahydroanthracene (structural formula ), 9-methyltetradecahydroanthracene (structural formula ), 9-ethyltetradecahydroanthracene (structural formula ), 9-n-propyltetradecahydroanthracene (structural formula ), 9-n-butyltetradecahydroanthracene (structural formula ), tetradecahydrophenanthrene (structural formula ), or one or more thereof.

[0044] Such as Figure 1As shown, in step S120, the reactants are transported into the reaction module of the microchannel reactor, and an oxidizing gas is introduced into the reaction module. The oxidizing gas reacts with the reactants at a preset temperature for a preset duration to form an intermediate product.

[0045] In some embodiments of the present disclosure, the reactants can be preheated by a preheating module before being transported into the reaction module. The temperature of the preheated reactants can be the same as the preset temperature required for their reaction. For example, the preset temperature can be 25°C to 170°C. For example, it can be 25°C, 50°C, 100°C, 150°C, or 170°C. When the preset temperature is 25°C, the reactants can be preheated to 25°C; when the preset temperature is 50°C, the reactants can be preheated to 50°C; when the preset temperature is 100°C, the reactants can be preheated to 100°C; when the preset temperature is 150°C, the reactants can be preheated to 150°C; when the preset temperature is 170°C, the reactants can be preheated to 170°C.

[0046] Optionally, the preset temperature can be 25°C to 50°C. The preset temperature is relatively low, and it is not easy to generate explosive gases, so the safety is relatively high. And within this temperature range, the energy consumption of the equipment is relatively low. For example, it can be 25°C, 30°C, 35°C, 40°C, 45°C, or 50°C. Of course, the preset temperature can also be other temperatures, which will not be listed one by one here.

[0047] The preset duration can be 20 seconds to 180 seconds. By reasonably setting the preset duration, the production efficiency can be improved. Preferably, the preset duration can be 20 seconds to 60 seconds. For example, it can be 20 seconds, 30 seconds, 40 seconds, 50 seconds, or 60 seconds. Of course, it can also be other durations, which will not be listed one by one here.

[0048] The preheated reactants can be transported into the reaction module of the microchannel reactor. At the same time, an oxidizing gas can also be introduced into the reaction module. The oxidizing gas reacts with the reactants under the action of a catalyst to form an intermediate product. The reaction product can be subjected to gas-liquid separation to collect the intermediate product and recycle the oxidizing gas.

[0049] It should be noted that the oxidizing gas can be introduced into the reaction module after being pressurized to a certain pressure by a booster pump. The oxidizing gas can be compressed by increasing its pressure. After compression, the gas volume increases, the gas flow rate slows down, the residence time in the microchannel increases, and the contact time between the gas and the reactants increases, which helps to improve the single-pass conversion rate of the finally formed alkyl ketone and alkyl alcohol. For example, the pressure of the oxidizing gas can be 0.3 MPa to 1.5 MPa. Preferably, it can be 0.3 MPa to 1.0 MPa. For example, it can be 0.3 MPa, 0.5 MPa, 0.7 MPa, 0.9 MPa, or 1.0 MPa.

[0050] In an exemplary embodiment of the present disclosure, the oxidizing gas may include oxygen and a diluting gas, wherein the diluting gas may include nitrogen, carbon dioxide or ozone. In some embodiments of the present disclosure, the content of oxygen in the oxidizing gas may be 5% to 100%, and the other gases are all diluting gases. For example, the content of oxygen in the oxidizing gas may be 5%, 20%, 40%, 60%, 80% or 100%. Of course, the content of oxygen in the oxidizing gas may also be other values, which will not be listed one by one here.

[0051] In an exemplary embodiment of the present disclosure, the volume ratio of the oxidizing gas to the reactant may be 3:1 to 20:1. For example, the volume ratio of the oxidizing gas to the reactant may be 3:1, 5:1, 10:1, 15:1 or 20:1. Preferably, the volume ratio of the oxidizing gas to the reactant may be 5:1 to 8:1. When the volume ratio of the oxidizing gas to the reactant is within this ratio range, the amount of gas that finally needs to be recycled can be reduced while ensuring the reaction rate. Since the amount of gas is relatively small, there is no need to build a complex gas circulation system, which can reduce the equipment investment and construction difficulty in gas circulation and lower the production cost.

[0052] In an exemplary embodiment of the present disclosure, the catalyst of the present disclosure may be a solid catalyst. For example, it may be zirconia, yttria, ceria, expanded graphite, β-zeolite, zinc chloride, iron chloride, cerium chloride, boric anhydride, metaboric acid, boron trioxide, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium bicarbonate, potassium bicarbonate, all of which are solid catalysts. The mesh number of the catalyst particles in the solid catalyst may be 80 mesh to 400 mesh. Since the particles of the solid catalyst are small, they are not easy to block the microchannels. Preferably, the mesh number of the catalyst particles in the solid catalyst may be 200 mesh to 300 mesh. For example, its mesh number may be 200 mesh, 220 mesh, 240 mesh, 260 mesh, 280 mesh or 300 mesh. Within the range of 200 mesh to 300 mesh, the catalyst particles can be evenly mixed with mineral oil and liquid paraffin, and the formed slurry reactant is not easy to precipitate, which can effectively reduce the sedimentation of the reactant in the microchannels.

[0053] In the present disclosure, the greater the weight of the solid catalyst, the greater the load on the microchannel and the higher the energy consumption. Therefore, the weight of the solid catalyst can be reduced as much as possible while ensuring the reaction rate. In the present disclosure, the weight of the solid catalyst may be 1% to 8% of the total weight of the reactants. Preferably, the weight of the solid catalyst may be 1% to 3% of the total weight of the reactants. A large number of experiments have shown that when the weight of the solid catalyst is within this range, the load on the microchannel reactor can be reduced while ensuring the reaction rate, thereby reducing the power consumption and production cost.

[0054] In an exemplary embodiment of the present disclosure, the reaction formula of the reactant and the oxidizing gas is as follows:

[0055]

[0056] Wherein, R1, R2, R3 and R4 each independently represent H, or a straight-chain or branched-chain alkane structure with 5 to 17 carbon atoms. The oxygen atoms introduced during the reaction are added to the secondary carbon in the form of a carbonyl or a hydroxyl group.

[0057] As Figure 1 shown, in step S130, the catalyst in the intermediate product is removed to form the target product.

[0058] The catalyst can be removed by means such as washing with water and filtration, thereby forming the target product. That is, the target product does not contain the catalyst, and the target product is usually an acidic product with a pH value of about 4 to 5.

[0059] As Figure 1 shown, in step S140, a basic solvent is added to the target product to obtain a mixture of alkyl ketones and alkyl alcohols.

[0060] The acidic target product can be adjusted to neutral. For example, a basic solvent can be added to the target product to make the pH value of the target product about 6 to 9. For example, an aqueous sodium hydroxide solution can be added to the target product until the pH value of the target product is within the range of 6 to 9. At this time, a mixture of alkyl ketones and alkyl alcohols is obtained. It should be noted that the mixture of alkyl ketones and alkyl alcohols at this time includes unreacted reactants, and the unreacted reactants can be removed to obtain a finished product mixture of alkyl ketones and alkyl alcohols.

[0061] The following specifically describes the details of the method for preparing the mixture of alkyl ketones and alkyl alcohols of the present disclosure through specific examples.

[0062] Example 1

[0063] Using dodecane as raw material, zirconia and ethylene glycol as catalysts to prepare a mixture of alkyl ketones and alkyl alcohols. Specifically, add dodecane, 1% by weight of zirconia powder with a particle size of 200 mesh, and 8% by weight of ethylene glycol to the premixing module of the microchannel reactor. The dodecane, zirconia powder, and ethylene glycol can be evenly mixed through the premixing module to obtain the reactants. Then, pump the reactants into the preheating module of the microchannel reactor at a speed of 200 grams per minute. The reactants are preheated to 165 °C through the preheating module, and then the preheated reactants are transported into the reaction module of the microchannel reactor. Oxygen and carbon dioxide are pressurized to 1.0 MPa through the gas inlet of the microchannel reactor and then transported into the reaction module of the microchannel reactor at a speed of 1800 milliliters per minute. It should be noted that the volume ratio of oxygen to carbon dioxide is 1:1. After oxygen enters the reaction module and reacts with the reactants for 30 seconds, a crude mixture of dodecanone and dodecanol is obtained through processes such as gas-liquid separation, filtration, pH adjustment to 6 - 9, water washing, and layering. In this example, the conversion rates of dodecanone and dodecanol are 31% and the selectivity is 82% as detected by gas chromatography.

[0064] Example 2

[0065] Using 1,3,5-trimethylcyclohexane as raw material and ethylenediamine as catalyst to prepare a mixture of alkyl ketones and alkyl alcohols. Specifically, add 1,3,5-trimethylcyclohexane and 1% by weight of ethylenediamine to the premixing module of the microchannel reactor. The 1,3,5-trimethylcyclohexane and ethylenediamine can be evenly mixed through the premixing module to obtain the reactants. Then, pump the reactants into the preheating module at a speed of 200 grams per minute. The reactants are preheated to 50 °C through the preheating module, and then the preheated reactants are transported into the reaction module of the microchannel reactor. Oxygen and carbon dioxide are pressurized to 1.0 MPa through the gas inlet of the microchannel reactor and then transported into the reaction module of the microchannel reactor at a speed of 1800 milliliters per minute. The volume ratio of oxygen to carbon dioxide is 1:1. After oxygen enters the reaction module and reacts with the reactants for 30 seconds, a crude mixture of 1,3,5-trimethylcyclohexanone and 1,3,5-trimethylcyclohexanol is obtained through processes such as gas-liquid separation, filtration, pH adjustment to 6 - 9, water washing, and layering. In this example, the conversion rates of 1,3,5-trimethylcyclohexanone and 1,3,5-trimethylcyclohexanol are 21% and the selectivity is 80% as detected by gas chromatography.

[0066] Example 3

[0067] Using cyclohexane as a raw material and sodium carbonate powder as a catalyst to prepare a mixture of alkyl ketones and alkyl alcohols. Specifically, cyclohexane and 3% by weight of sodium carbonate powder with a particle size of 200 mesh are added to the premixing module of the microchannel reactor. The cyclohexane and sodium carbonate powder can be evenly mixed through the premixing module to obtain a reactant. The reactant is transported to the preheating module at a speed of 60 grams per minute through a material pump. The reactant is preheated to 30 degrees Celsius through the preheating module, and then the preheated reactant is transported into the reaction module. A mixed gas of oxygen and ozone is pressurized to 0.6 MPa through the gas inlet of the microchannel reactor and sent into the reaction module at a speed of 900 milliliters per minute. It should be noted that the concentration of oxygen in the mixed gas of ozone and oxygen is 92-93%. After the oxygen enters the reaction module and contacts the reactant for 60 seconds, through processes such as gas-liquid separation, filtration, adjusting the pH to 6-9, water washing, and layering, a crude mixture of cyclohexanone and cyclohexanol is obtained. In this example, the conversion rates of cyclohexanone and cyclohexanol are 35% and the selectivity is 83% as detected by gas phase chromatography.

[0068] Example 4

[0069] Using isomeric tridecane (2-methyldodecane) as a raw material and sodium carbonate powder as a catalyst to prepare a mixture of alkyl ketones and alkyl alcohols. Specifically, isomeric tridecane and 1% by weight of sodium carbonate powder with a particle size of 100 mesh are added to the premixing module of the microchannel reactor. The isomeric tridecane and sodium carbonate powder are evenly mixed through the premixing module to obtain a reactant. The reactant is transported to the preheating module at a speed of 600 grams per minute through a material pump. The reactant is preheated to 30 degrees Celsius through the preheating module, and then the preheated reactant is transported into the reaction module. A mixed gas of oxygen and ozone is pressurized to 1.2 MPa through the gas inlet of the microchannel reactor and sent into the reaction module at a speed of 3600 milliliters per minute. It should be noted that the concentration of oxygen in the mixed gas of ozone and oxygen is 86%. After the oxygen enters the reaction module and contacts the reactant for 120 seconds, through processes such as gas-liquid separation, filtration, adjusting the pH to 6-9, water washing, and layering, a crude mixture of isomeric tridecanone and isomeric tridecanol is obtained. In this example, the conversion rates of isomeric tridecanone and isomeric tridecanol are 30% and the selectivity is 85% as detected by gas phase chromatography.

[0070] Example 5

[0071] Using n-hexadecane as raw material and boric acid powder as catalyst to prepare mixed alkyl ketones and alkyl alcohols. Specifically, n-hexadecane and 5% by weight of boric acid powder with a particle size of 200 mesh are added to the premixing module of the microchannel reactor. The n-hexadecane and boric acid powder are evenly mixed through the premixing module to obtain the reactants. The reactants are transported to the preheating module at a speed of 600 grams per minute by a material pump. The reactants are preheated to 170 degrees Celsius through the preheating module, and then the preheated reactants are transported into the reaction module. A mixed gas of oxygen and nitrogen is pressurized to 1.0 MPa and transported into the reaction module at a speed of 1900 milliliters per minute through the inlet of the microchannel reactor. It should be noted that the content of oxygen in the mixed gas of oxygen and nitrogen is 5%. After the oxygen enters the reaction module and contacts the reactants for 100 seconds, a crude mixture of n-hexadecanone and n-hexadecanol is obtained through processes such as gas-liquid separation, filtration, pH adjustment to 6-9, water washing, and stratification. In this example, the conversion rates of n-hexadecanone and n-hexadecanol are 25% and the selectivity is 87% as detected by gas chromatography.

[0072] Example 6

[0073] Using isooctane (2,2,4-trimethylpentane) as raw material and ferric chloride powder and acetic anhydride as catalysts to prepare mixed alkyl ketones and alkyl alcohols. Specifically, isooctane and 0.5% by weight of ferric chloride powder with a particle size of 200 mesh and 5% by weight of acetic anhydride are added to the premixing module of the microchannel reactor. The isooctane, ferric chloride powder, and acetic anhydride are evenly mixed through the premixing module to obtain the reactants. The reactants are transported to the preheating module at a speed of 800 grams per minute by a material pump. The reactants are preheated to 50 degrees Celsius through the preheating module, and then the preheated reactants are transported into the reaction module. A mixed gas of oxygen and nitrogen is pressurized to 1.2 MPa and enters the reaction module at a speed of 4800 milliliters per minute through the inlet of the microchannel reactor. It should be noted that the content of oxygen in the mixed gas of oxygen and nitrogen is 50%. After the oxygen enters the reaction module and contacts the reactants for 20 seconds, a crude mixture of isooctanone and isooctanol is obtained through processes such as gas-liquid separation, filtration, pH adjustment to 6-9, water washing, and stratification. In this example, the conversion rates of isooctanone and isooctanol are 25% and the selectivity is 80% as detected by gas chromatography.

[0074] Example 7

[0075] Using n-octadecane as raw material and sodium bicarbonate powder as catalyst to prepare mixed alkyl ketones and alkyl alcohols. Specifically, n-octadecane and 1% by weight of sodium bicarbonate powder with a particle size of 200 mesh are added to the premixing module of the microchannel reactor. The n-octadecane and sodium bicarbonate powder are evenly mixed through the premixing module to obtain the reactants. The reactants are transported to the preheating module at a speed of 200 grams per minute by a material pump, and the reactants are preheated to 50 °C through the preheating module. Subsequently, the preheated reactants are transported into the reaction module. A mixed gas of oxygen and ozone is pressurized to 1.2 MPa through the air inlet of the microchannel reactor and transported into the reaction module at a speed of 4000 milliliters per minute. It should be noted that the content of oxygen in the mixed gas of oxygen and ozone is 86%. After oxygen enters the reaction module and reacts with the reactants for 50 seconds, a crude mixture of n-octadecanone and n-octadecanol is obtained through processes such as gas-liquid separation, filtration, pH adjustment to 6 - 9, water washing, and stratification. In this example, the conversion rates of n-octadecanone and n-octadecanol are 21% and the selectivity is 89% as detected by gas chromatography.

[0076] Example 8

[0077] Using mixed paraffin wax (the gas chromatography ratio of normal carbon 12:13:14 = 3:4:3) as raw material and boron trioxide powder as catalyst to prepare alkyl ketones and alkyl alcohols. Specifically, mixed paraffin wax and 3% by weight of boron trioxide powder with a particle size of 300 mesh are added to the premixing module of the microchannel reactor. The mixed paraffin wax and boron trioxide powder are evenly mixed through the premixing module to obtain the reactants. The reactants are transported to the preheating module at a speed of 300 grams per minute by a material pump, and the reactants are preheated to 30 °C through the preheating module. Subsequently, the preheated reactants are transported into the reaction module. A mixed gas of oxygen and nitrogen is pressurized to 1.0 MPa through the air inlet of the microchannel reactor and transported into the reaction module at a speed of 3000 milliliters per minute. It should be noted that the content of oxygen in the mixed gas of oxygen and nitrogen is 10%. After oxygen enters the reaction module and reacts with the reactants for 30 seconds, a crude mixture of mixed alkyl ketones and alkyl alcohols is obtained through processes such as gas-liquid separation, pH adjustment to 6 - 9, water washing, and stratification. In this example, the conversion rates of alkyl ketones and alkyl alcohols are 32% and the selectivity is 80% as detected by gas chromatography.

[0078] Table 1 Test information and test results of each example in the present disclosure

[0079]

[0080] As can be seen from Table 1, different types of mixtures of alkyl ketones and alkyl alcohols can be prepared by adding different raw materials and catalysts. The reaction time in each example is basically between 30 s and 120 s, the conversion rate is between 21% and 35%, and the product selectivity is between 80% and 89%. It can be seen that the preparation method of alkyl ketones and alkyl alcohols in the present disclosure has a rapid reaction and relatively high conversion rate and selectivity. At the same time, since the main reaction process in the preparation method of the present disclosure is carried out in a microchannel reactor, during this process, due to the small space in the microchannel reactor, the amount of oxidizing gas contained therein is relatively small. Therefore, a large amount of heat will not be generated during the reaction, the possibility of explosion during the preparation process is small, the safety factor is high, which is conducive to industrial scale-up production.

[0081] Other embodiments of the present disclosure will be readily apparent to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of the present disclosure that follow the general principles of the present disclosure and include known common knowledge or conventional technical means in the technical field not disclosed in the present disclosure. The specification and examples are only illustrative, and the true scope and spirit of the present disclosure are pointed out by the appended claims.

Claims

1. A method for preparing a mixed alkyl ketone and alkyl alcohol, characterized in that: include: Mixing mineral oil, liquid paraffin and a catalyst to form a reactant; The reactants are transported to a reaction module of a microchannel reactor, and an oxidizing gas is introduced into the reaction module, wherein the oxidizing gas reacts with the reactants at a preset temperature for a preset time to form an intermediate product; removing the catalyst in the intermediate product to form a target product; A basic solvent is added to the target product to obtain a mixture of alkyl ketone and alkyl alcohol.

2. The preparation method according to claim 1, characterized in that: The oxidizing gas includes oxygen and a diluent gas, and the diluent gas includes nitrogen, carbon dioxide or ozone.

3. The preparation method according to claim 1, characterized in that: The catalyst includes one or more of zirconium oxide, yttrium oxide, cerium oxide, ethylene glycol, 1,3-propylene glycol, 1,4-butanediol, hexylene glycol, acetic anhydride, expanded graphite, β-zeolite, zinc chloride, ferric chloride, cerium chloride, anhydrous boric acid, metaboric acid, boron trioxide, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium bicarbonate, potassium bicarbonate, ammonia, methylamine, ethylamine, dimethylamine or diethylamine.

4. The preparation method according to claim 1, characterized in that: The preset temperature is 25° C. to 170° C.; the preset time is 20 seconds to 180 seconds.

5. The preparation method according to claim 1, characterized in that: The reactants include at least one of straight-chain alkanes with 8-20 carbon atoms, branched-chain alkanes with 8-20 carbon atoms, cycloalkanes with 6-18 carbon atoms, and substituted cycloalkanes with 6-18 carbon atoms.

6. The preparation method according to claim 5, characterized in that: The straight-chain alkanes having 8 to 20 carbon atoms include: One or more of n-octane, n-nonane, n-decane, n-undecane, n-dodecane, n-tridecane, n-tetradecane, n-pentadecane, n-hexadecane, n-heptadecane, n-octadecane, n-nonadecane and n-eicosane; The branched alkanes having 8 to 20 carbon atoms include: 2-Methylheptane, 3-Methylheptane, 4-Methylheptane, 2-Methyloctane, 3-Methyloctane, 4-Methyloctane, 2,6-Dimethylheptane, 3,5-Dimethylheptane, 2-Methylnonane, 3-Methylnonane, 4-Methylnonane, 5-Methylnonane, 2,7-Dimethyloctane, 2,6-Dimethyloctane, 3,6-Dimethyloctane, 2-Methyldecane, 3-Methyldecane, 4-Methyldecane, 2,8-Dimethylnonane, 2,7-Dimethylnonane one or more of 2,2,4-trimethylpentane, 3,8-dimethyldecane, 5-ethyldecane, 2-methylundecane, 3-methylundecane, 4-methylundecane, 2-methyldodecane, 3-methyldodecane, 2,9-methylundecane, 6-ethylundecane, 3-methyltridecane, 5-ethyldodecane, 4-methyltetradecane, 5-methylpentadecane, 6-methylhexadecane, 3-methylheptadecane, 6-methyloctadecane, 5-methylnonadecane or 2,2,4-trimethylpentane; The cycloalkanes and substituted cycloalkanes having 6 to 18 carbon atoms include: One or more of cyclohexane, methylcyclohexane, 1,3-dimethylcyclohexane, 1,2-dimethylcyclohexane, 1,4-dimethylcyclohexane, ethylcyclohexane, 1,2,4-trimethylcyclohexane, 1,2,5-trimethylcyclohexane, 1-methyl-3-ethylcyclohexane, decahydronaphthalene, 1-methyldecahydronaphthalene, 1-ethyldecahydronaphthalene, 1-n-propyldecahydronaphthalene, tetradecahydroanthracene, 9-methyltetradecahydroanthracene, 9-ethyltetradecahydroanthracene, 9-n-propyltetradecahydroanthracene, 9-n-butyltetradecahydroanthracene and tetradecahydrophenanthrene.

7. The preparation method according to any one of claims 1 to 6, characterized in that: The catalyst includes zirconium oxide, yttrium oxide, cerium oxide, expanded graphite, beta-zeolite, zinc chloride, ferric chloride, cerium chloride, anhydrous boric acid, metaboric acid, boron trioxide, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium bicarbonate, and potassium bicarbonate, all of which are solid catalysts, and the mesh number of the catalyst particles in the solid catalyst is 80 mesh to 400 mesh.

8. The preparation method according to claim 7, characterized in that: The weight of the solid catalyst is 1% to 8% of the total weight of the reactants.

9. The preparation method according to claim 2, characterized in that: The oxygen content in the oxidizing gas is 5% to 100%.

10. The preparation method according to claim 2, characterized in that: The volume ratio of the oxidizing gas to the reactant is 3:1 to 20:1.

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