JP2014231504A - Method for producing carbon compound - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce a specific carbon compound, for example hexadecane (normal cetane), in high purity to contribute to improvement of a cetane value and reduction of a sulfur content of light oil.SOLUTION: The method for producing a carbon compound comprises the step of reacting compressed water of an aqueous potassium carbonate solution comprising 288 moles of water and 8 moles of potassium carbonate, 24 moles of carbon dioxide, and 49 moles of hydrogen in a reaction vessel of 300°C under a pressure condition of 2.0 MPa while controlling cooling so that a heat quantity ΔH (2506.28 kJ per 1 mole of normal cetane) calculated on the basis of the heat of formation (ΔHp) of the carbon compound (normal cetane) to be generated is removed from the reaction vessel as a whole to generate 1 mole of normal cetane. Hereby, for example if the generated normal cetane is mixed to light oil having a cetane value of 50 in a 1:1 ratio, there is theoretically obtained light oil having a cetane value of 75 which can exhibit very excellent ignitability, and also can reduce a sulfur content, a nitrogen content, and an oxygen content by half.

Description

  The present invention relates to a carbon compound production method capable of producing a specific carbon compound with high purity from compressed water composed of an aqueous potassium carbonate solution, carbon dioxide and hydrogen.

  For example, an invention of a method of producing a synthesis gas containing carbon monoxide and hydrogen from natural gas and synthesizing a carbon compound such as gasoline from the synthesis gas through a GTL (Gas to Liquids) process in a Fischer-Tropsch reaction system, The following patent documents 1, 2 and the like are proposed.

  However, the GTL process proposed in the following Patent Documents 1 and 2 uses carbon monoxide as a raw material, so the reaction itself is unstable, and as a mixture of light oil, kerosene and other hydrocarbons, and oil components together with gasoline. Since a carbon compound is produced, there is a problem that a step of separating each component by distillation or the like is further required before the product (carbon compound) is used for various industrial uses.

JP-A-6-184559 JP 2005-522565 Gazette

On the other hand, it is known that plants perform photosynthesis that produces specific sugars, starches, and other vegetable oils from water (H ₂ O) and carbon dioxide (CO ₂ ). In this photosynthesis, potassium is used as an enzyme (catalyst). Plants produce hydrogen (H ₂ ) and carbon dioxide (CO ₂ ) using potassium carbonate as a catalyst and the produced sugar and water (H ₂ O) as reactants. Furthermore, fatty acids (vegetable oils) are produced using the same potassium carbonate as a catalyst and the produced H ₂ and CO ₂ as reactants. Plants carry out these reactions at normal temperature and normal pressure. If such reactions can be artificially constructed at high temperature and high pressure, specific carbon compounds can be obtained industrially with high purity. There is a possibility.

  The present invention has been proposed in view of the above circumstances, industrially constructing a reaction in which a plant generates a fatty acid (vegetable oil) using potassium carbonate as a catalyst, and using carbon dioxide to stably advance the reaction itself, It is an object of the present invention to newly provide a carbon compound production method capable of producing a targeted carbon compound such as specific hydrocarbons and oils with high purity without requiring a step of separating each component by distillation.

  In order to achieve the above object, the present invention provides a carbon compound production method for producing a carbon compound containing at least carbon and hydrogen as constituent elements and, if necessary, oxygen, comprising a compressed potassium carbonate solution. In a reactor under predetermined conditions, water, carbon dioxide, and hydrogen are deprived of calorific value ΔH calculated based on the heat of formation of the carbon compound to be produced, the number of moles of carbon and the number of moles of oxygen in the carbon compound. The reaction is carried out while cooling the reactor to produce the carbon compound, the by-product is potassium hydrogen carbonate, and the calorific value ΔH is represented by the following [Equation 1]. .

  In addition, an aqueous solution of potassium hydrogen carbonate as the by-product is charged into a second reactor under reduced pressure as compared with the reaction in the reactor to produce carbon dioxide and an aqueous potassium carbonate solution. The potassium carbonate aqueous solution is regenerated while promoting the reaction in the second reactor to the production side except for the carbon dioxide.

  Furthermore, excess water is removed from the regenerated potassium carbonate aqueous solution, and the potassium carbonate aqueous solution from which the excess water has been removed is pressurized and used as compressed water comprising a potassium carbonate aqueous solution that functions as a reaction catalyst in the reactor. And

  In the carbon compound production method according to the present invention, the compressed water is preferably added to the reactor by spraying. More preferably, the carbon dioxide and hydrogen produced from a steam reforming process are used.

  Moreover, the carbon compound manufacturing method according to the present invention is characterized in that the carbon compound to be manufactured consists only of a specific isomer.

The present invention is an industrial carbon compound production method capable of efficiently obtaining a specific carbon compound by using as a model a plant reaction that produces vegetable oil using potassium carbonate as a catalyst and H ₂ and CO ₂ as reactants. Has been built. Specifically, the heat of formation (ΔHp) of the carbon compound to be generated in the reactor of the above [Equation 1], such as compressed water composed of an aqueous potassium carbonate solution, carbon dioxide, and hydrogen, etc. The reaction is performed while controlling the cooling of the reactor so that the amount of heat ΔH calculated based on the above is taken, and at least carbon and hydrogen are included, and if necessary, a carbon compound composed of constituent elements including oxygen is generated, and a by-product It is a carbon compound manufacturing method which produces | generates potassium hydrogen carbonate as a thing. Therefore, since the carbon dioxide is used as a raw material in the reactor, the reaction proceeds stably. Further, the amount of heat ΔH calculated based on the heat of formation (ΔHp) of the carbon compound to be generated is deprived, that is, the amount of heat calculated based on the heat of formation different for various carbon compounds is used as an index in the reactor. By controlling this reaction, the specific carbon compound to be obtained can be produced with high purity. In particular, since only a specific carbon compound is produced based on the heat of formation, even one isomer such as isooctane and normal octane can be produced with high purity. In addition, since the potassium carbonate in compressed water works as a catalyst, the catalyst packed bed conventionally provided in the reactor can be made unnecessary, and the size of the reactor can be reduced.

  In the present invention, a potassium hydrogen carbonate aqueous solution as a by-product was introduced into a second reactor under reduced pressure as compared with the reaction in the reactor to produce carbon dioxide and a potassium carbonate aqueous solution. It is the structure which reproduces | regenerates potassium carbonate aqueous solution, promoting the reaction in a 2nd reactor to the production | generation side except carbon dioxide. Furthermore, the excess water contained in the regenerated potassium carbonate aqueous solution and removed in the reactor is removed, and the potassium carbonate aqueous solution from which this excess water is removed is pressurized, and this is removed from the potassium carbonate aqueous solution that functions as a reaction catalyst in the reactor. It is the structure used as compressed water. Accordingly, it is possible to circulate and use potassium carbonate in a continuous operation of the system (plant), and it is possible to proceed with extremely rational carbon compound production.

  In the present invention, the reaction for producing the carbon compound in the reactor can be efficiently advanced by adding the compressed water to the reactor by spraying. If the raw material carbon dioxide or hydrogen is generated from a steam reforming process, hydrogen produced by hydrogen production based on the steam reforming process and carbon dioxide produced in parallel are converted into desired carbon. It can be effectively used to obtain a compound. As described above, in the present invention, only a specific isomer of the produced carbon compound can be obtained with high purity.

It is a flowchart which shows the outline of the process of the carbon compound manufacturing method which concerns on this invention. It is explanatory drawing which shows the change of the mass of each substance from a reactor inlet to an outlet qualitatively.

  Hereinafter, an embodiment of a carbon compound production method according to the present invention will be described with reference to the drawings. This embodiment is merely an example of the present invention, and the present invention can be modified in various ways without departing from the matters described in the claims.

The outline of the carbon compound manufacturing method according to the present invention will be described with reference to FIG. First, as a general example, a carbon compound production method for obtaining a carbon compound represented by the chemical formula C _n H _m O _l will be described. In the following chemical formula, (G) indicates gas (vapor), (L) indicates liquid, and (S) indicates solid. Moreover, n and m which are variables appearing in the chemical formula are real numbers greater than 0, and l of the same variable is a real number greater than 0 and 0. In the description of this embodiment, a shell and tube reactor is employed as a reactor for producing a carbon compound.

As shown in FIG. 1, first, it is suitable for reacting a predetermined amount of carbon dioxide (CO ₂ ), hydrogen (H ₂ ), and compressed water composed of an aqueous potassium carbonate solution (K ₂ CO ₃ + H ₂ O). Adjust the temperature and pressure to get into the state. 1.5 nmole of carbon dioxide and (2n + m / 2-l) mol of hydrogen are taken out of the tank, and are passed through a compressor and a heater, respectively, at a temperature of 200 to 600 ° C. suitable for reaction, 1.0 to 5. The pressure is set to 0 MPa. Also, a potassium carbonate aqueous solution composed of 18 nmoles of water (L) and 0.5 nmoles of potassium carbonate is pumped out of the tank, and is made into compressed water through a heater to a temperature of 200 to 600 ° C. suitable for reaction. The pressure is set to 0 to 5.0 MPa. As a state suitable for the reaction, the temperature condition is appropriately determined from a temperature range of 200 to 600 ° C. which is a temperature higher than the normal boiling point of the carbon compound to be produced and is appropriate in view of the reaction rate. The 300-550 ° C. can be a practical temperature condition. Further, the pressure condition is appropriately determined from the range of 1.0 to 5.0 MPa as the pressure at which the generated water vapor becomes superheated vapor and the condensation at which part of the water vapor becomes liquid water does not occur. The If the pressure is set too high, the load on the compressor is large, which is economically disadvantageous.

  Furthermore, the compressed water consisting of carbon dioxide, hydrogen, and potassium carbonate aqueous solution whose temperature and pressure are adjusted to predetermined values is converted into a shell-and-tube reactor (hereinafter simply referred to as “reactor consisting of a plurality of tubes”). The reactor is referred to as “reactor”), and these are reacted under the conditions of a temperature of 200 to 600 ° C. and a pressure of 1.0 to 5.0 MPa. In particular, it is preferable to use a spray nozzle or the like to input compressed water from two or more locations to the shell side of the reactor by spraying. In order to use potassium carbonate contained in the aqueous solution as a catalyst, it is necessary to be atomized in order to increase the contact area. By inputting from two or more places, potassium carbonate is used as a catalyst. It can be used efficiently. In addition, as will be described later, cooling water is introduced to the tube side of the reactor to take away heat generated by the reaction. The reaction formula of the reaction proceeding in the reactor is as shown in [Chemical Formula 1] below.

Since the reaction of [Chemical Formula 1] is an exothermic reaction, cooling of the entire reactor is controlled using means such as circulating a cooling medium (for example, cooling water) to the tube side of the reactor. In other words, the reaction proceeds while taking heat (enthalpy). Specifically, the amount of heat ΔH (MJ / kmol) at which the reactor is cooled is controlled in a state where the temperature of the reactor itself is controlled to be constant (that is, in a state where the temperatures at the inlet and the outlet of the reactor are equal). ), The heat of formation ΔHp (MJ / kmol) of the carbon compound (C _n H _m O _l ) to be generated, the number of moles of carbon n and the number of moles of oxygen 1 in the carbon compound to be generated [Expression 2]

  Then, by adjusting the flow rate F of the cooling water circulating on the tube side of the reactor to a value derived from the following equation (2), the amount of heat ΔH is taken from the entire reactor (the enthalpy of ΔH is Deprived) can allow the reaction to proceed to the production side, i.e. a specific carbon compound corresponding to its heat of formation can be produced in high purity.

  Here, the reaction represented by the reaction formula of [Chemical Formula 1] will be described.

The reaction formula for producing a carbon compound (C _n H _m O _l ) using potassium carbonate as a catalyst and carbon dioxide and hydrogen as raw materials is as shown in the following [Chemical Formula 2].

  The above [Chemical 2] is derived from the following reaction formulas [Chemical 3].

In addition, as in the case of the reaction product in [Chemical Formula 1], potassium carbonate is made into an aqueous solution of potassium hydrogen carbonate (KHCO ₃ ) so that potassium carbonate becomes zero at the outlet of the reactor. The reaction formula is as shown in [Chemical Formula 4] below. Incidentally, in order to completely and aqueous potassium hydrogen carbonate solution _{(KHCO 3 + H 2 O)} , excess water is added. That is, in the above [Chemical Formula 1], since 18 nmol of water (L) is input to the reactor as compressed water, the actual reaction is as shown in [Chemical Formula 5] below, and 17.5 nmol of It can be said that water (L) is added in excess. If the reaction can proceed so that potassium carbonate becomes zero at the reactor outlet, the reaction in [Chemical Formula 5] is limited to 17.5 nmoles of water (L) as an amount corresponding to excess water. Not.

[Chemical Formula 1] is thus derived from the reaction formulas of [Chemical Formula 2] and [Chemical Formula 5]. Based on the heat of formation (ΔHp) of the carbon compound to be produced in the above formula [1] in a reactor at a temperature of 200 to 600 ° C. and a pressure of 1.0 to 5.0 MPa. The specific carbon compound (C _n H _m O _l ) can be produced with high purity by taking the calorific value ΔH calculated in this way from the entire reactor. Moreover, potassium hydrogen carbonate will be produced as a by-product.

The point of depriving the entire reactor of the amount of heat ΔH calculated based on the heat of formation (ΔHp) of the carbon compound to be produced in the formula of [Equation 1] is the reaction of [Chemical Formula 1]. It is also necessary to avoid going in the opposite direction. Carbon dioxide and hydrogen are produced from the produced carbon compounds C _n H _m O _l (G) and (2n−1) H ₂ O (G) by an endothermic steam reforming reaction, that is, the reverse reaction is performed. Because there is a risk of moving forward. Therefore, it is preferable to control cooling by circulating cooling water throughout the reactor. In addition, as shown in FIG. 2, the optimal reaction is achieved by making potassium carbonate into an aqueous potassium hydrogen carbonate solution so that potassium carbonate becomes zero at the outlet of the reactor as in the case of the reactants (CO ₂ , H ₂ ). Can be obtained.

A product comprising a carbon compound as C _n H _m O _l (G), water vapor as (2n−1) H ₂ O (G), and an aqueous potassium hydrogen carbonate solution (nKHCO ₃ +17.5 nH ₂ O (L)) After output from the reactor, they are led to a condenser to be separated in a subsequent process, condensed while adjusting the temperature and pressure, and as shown in the following [Chemical Formula 6], the carbon compound (C _n H _m O _l ) and water vapor (2n−1) H ₂ O (G) are changed to a liquid state. (2n-1) By making the steam of H ₂ O into a liquid, there is also an effect that the steam reforming reaction does not occur. Note that some carbon compounds, such as methane, do not become liquid at that temperature and pressure even when cooled. Some carbon compounds become solids through condensers.

Subsequently, these are introduced into a liquid-liquid separator (a gas-liquid separator in the case of a non-condensable carbon compound such as methane, or a solid-liquid separator in the case of a carbon compound that becomes a solid through a condenser), separating the carbon compounds _{(C n H m O l)} . On the other hand, the separated potassium hydrogen carbonate aqueous solution is decompressed and introduced into a solution regeneration tower which is a second reactor. In the solution regeneration tower, potassium carbonate is regenerated in the form of an aqueous solution according to the following reaction formula [7]. When potassium hydrogen carbonate is introduced into the solution regeneration tower, (19.5 n-1) moles of water (L) is present, so the actual reaction is performed as shown in the following [Chemical Formula 8]. Is done.

  In the regeneration of potassium carbonate in the solution regeneration tower, the reaction shown in the above [Chemical 8] can be promoted to the production side by removing the produced carbon dioxide, thereby efficiently producing potassium carbonate. Can play.

  Next, the potassium carbonate aqueous solution regenerated in the solution regeneration tower is pressurized with a pump and heated with a heater to control the dryness of the wet steam, and the carbon compound which is excess water using a gas-liquid separator Remove the water (water produced in the reactor) generated when producing The potassium carbonate aqueous solution from which excess water has been removed can be reused as it is as compressed water for the potassium carbonate aqueous solution which is a reaction catalyst for the production of carbon compounds. That is, circulation use of an aqueous potassium carbonate solution is realized.

  The dryness of the wet steam when removing excess water (water generated in the reactor) can be expressed by the following [Equation 4].

  The reaction for removing excess water (water generated in the reactor) using a gas-liquid separator is as shown in [Chemical 9] below.

That is, by removing only (2n-1) moles (number of moles produced by the reaction) as water vapor from (20n-1) moles of water (L) in which 0.5 nmol of potassium carbonate is dissolved, The potassium carbonate aqueous solution can be reused as a reaction catalyst for the reaction in the reactor as the concentration (0.5 nK ₂ CO ₃ +18 nH ₂ O (L)) for reacting in the reactor for producing the carbon compound. It becomes.

  In the present invention, carbon dioxide and hydrogen, which are raw materials for producing a desired carbon compound, can be used together with a hydrogen production plant based on the steam reforming process, if generated from the steam reforming process. This is convenient because a desired carbon compound can be obtained. For example, the present invention separates each component by distillation or the like required in a GTL process for obtaining gasoline from conventional natural gas by being provided with a hydrogen production plant based on a natural gas steam reforming process. A process can be dispensed with.

As described above, in the present invention, industrial carbon that can efficiently obtain a specific carbon compound using, as a model, a plant reaction that produces vegetable oil using potassium carbonate as a catalyst and H ₂ and CO ₂ as reactants. It is constructed as a compound manufacturing method. Specifically, compressed water composed of an aqueous potassium carbonate solution, carbon dioxide, and hydrogen are generated in a reactor under predetermined conditions in accordance with the heat of formation (ΔHp) of the carbon compound to be generated in the above formula [1]. It generates by making it react, controlling cooling so that calorie | heat amount (DELTA) H calculated based on it may be taken from a reactor. As a result, the reaction proceeds stably because carbon dioxide is used as a raw material, and the specific carbon compound to be obtained is produced with high purity by controlling the reaction using different heats of formation for various carbon compounds as an index. be able to. The by-product potassium bicarbonate is then regenerated to potassium carbonate and can be used for recycling. In addition, since the potassium carbonate in compressed water works as a catalyst, the catalyst packed bed conventionally provided in the reactor can be made unnecessary, and the size of the reactor can be reduced. Therefore, extremely rational carbon compound production can be promoted.

  Hereinafter, some examples of the carbon compound production method according to the present invention will be described by taking specific carbon compounds as examples.

Example 1
In Example 1, a methane production method will be described as an example of a carbon compound production method for producing a hydrocarbon (C _n H _m ) represented by a carbon compound C _n H _m O _l (l = 0). The reaction formula in the reactor for producing methane (CH ₄ ) using carbon dioxide (CO ₂ ) and hydrogen (H ₂ ) as raw materials using potassium carbonate (K ₂ CO ₃ ) as a catalyst is shown in the following [Chemical Formula 10]. It is as follows. In this example, the reactor outlet temperature, ie, the reaction temperature, was set to 300 ° C., and the reactor outlet pressure, ie, the reaction pressure, was set to 2.0 MPa. If it is 300 degreeC, it is the temperature more than the normal boiling point of methane, and a suitable reaction rate will be obtained. If the pressure is 2.0 MPa, it is sufficiently smaller than the saturated vapor pressure at the temperature of the generated water vapor, so that a part of the water vapor does not condense into liquid water.

In the reaction of [Chemical Formula 10], the amount of heat ΔH ₁ (MJ / kmol) taken by the cooling water circulating on the tube side of the reactor is 205.46 kJ per mole of methane to be produced. Then, by adjusting the flow rate F of the cooling water circulating on the tube side of the reactor so as to satisfy the above [Equation 3], the heat amount ΔH ₁ can be taken while appropriately cooling the entire reactor.

The reaction in the condenser after the methane (CH ₄ ) produced by the reaction of the above [Chemical Formula 10] and potassium hydrogen carbonate as a by-product is output from the reactor is as shown in the following [Chemical Formula 11]. Furthermore, since methane is a non-condensable carbon compound, it is introduced into a gas-liquid separator and separated. Thereafter, the reaction for regenerating potassium carbonate by introducing the potassium hydrogen carbonate aqueous solution after separating methane into the solution regeneration tower is as shown in the following [Chemical Formula 12]. In the regeneration of potassium carbonate, the reaction proceeds while removing the generated carbon dioxide, and the reaction shown in the above [Chemical 12] is promoted to the production side.

  In addition, for the potassium carbonate aqueous solution regenerated in the solution regeneration tower, the reaction for removing excess water using a gas-liquid separator in order to contribute to the circulation use of the potassium carbonate aqueous solution is as shown in [Chemical Formula 13] below.

In Table 1 below, for an example of individual hydrocarbons (C _n H _m ) produced according to the present invention, the amount of heat ΔH taken from the reactor to produce, the heat of formation ΔHp of the hydrocarbon, the temperature of the reactor Conditions and pressure conditions are shown respectively.

  Here, as understood from [Table 1], in the present invention, for example, only one (specific) isomer can be produced with high purity, even with respect to isomers such as normal octane and isooctane. Since the value of heat of formation ΔHp differs for each isomer, the amount of heat ΔH to be taken also differs between isomers. By controlling the cooling of the reactor using this different amount of heat ΔH as an index, only the desired isomer has high purity. Will be generated.

(Example 2)
In Example 2, a phenol production method will be described as an example of a carbon compound production method for producing an alcohol, an ether, or the like represented by a carbon compound C _n H _m O _l (l = 1). The reaction formula in a reactor for producing phenol (C ₆ H ₆ O) using potassium carbonate (K ₂ CO ₃ ) as a catalyst and carbon dioxide (CO ₂ ) and hydrogen (H ₂ ) as raw materials is shown below. 14]. In this example, the reactor outlet temperature, ie, the reaction temperature, was set to 300 ° C., and the reactor outlet pressure, ie, the reaction pressure, was set to 2.0 MPa. If it is 300 degreeC, it is the temperature more than the normal boiling point of phenol, and a suitable reaction rate will be obtained. If the pressure is 2.0 MPa, it is sufficiently smaller than the saturated vapor pressure at the temperature of the generated water vapor, so that a part of the water vapor does not condense into liquid water.

In the reaction of [Chemical Formula 14], the amount of heat ΔH ₂ (MJ / kmol) taken by the cooling water circulating on the tube side of the reactor is 640.94 kJ per mole of phenol produced. Then, by adjusting the flow rate F of the cooling water circulating on the tube side of the reactor so as to satisfy the above [Equation 3], the heat amount ΔH ₂ can be taken while appropriately cooling the entire reactor.

The reaction in the condenser after the phenol (C ₆ H ₆ O) produced by the reaction of the above [Chemical Formula 14] and potassium hydrogen carbonate as a by-product is output from the reactor is as shown in [Chemical Formula 15] below. It is. Furthermore, after introducing phenol into the solid-liquid separator and separating it, the reaction of introducing an aqueous potassium hydrogen carbonate solution into the solution regeneration tower to regenerate potassium carbonate is as shown in the following [Chemical Formula 16]. In the regeneration of potassium carbonate, the reaction proceeds while removing the produced carbon dioxide, and the reaction shown in the above [Chemical Formula 16] is promoted to the production side.

  Further, for the potassium carbonate aqueous solution regenerated in the solution regeneration tower, the reaction for removing excess water using a gas-liquid separator in order to contribute to the circulation use of the potassium carbonate aqueous solution is as shown in [Chemical Formula 17] below.

In Table 2 below, for the examples of individual alcohols and ethers produced according to the present invention (C _n H _m O _l (l = 1)), the amount of heat ΔH taken from the reactor to produce, its hydrocarbons Shows the heat of formation ΔHp, the temperature condition of the reactor and the pressure condition.

  As understood from [Table 2], in the present invention, for example, ethanol and dimethyl ether are in a structural isomer relationship, but since the numerical value of the heat of formation ΔHp is different, only one (specific) isomer is highly purified. Can be manufactured. Moreover, although methanol and ethanol are produced | generated as aqueous solution containing potassium carbonate, since these can be regarded as the solution in which hydrogen was stored, it is useful to manufacture by this invention.

Example 3
In Example 3, as an example of a carbon compound production method for producing an aliphatic carboxylic acid, ester, aromatic carboxylic acid or the like represented by a carbon compound C _n H _m O _l (l = 2), a linoleic acid production method is used. Will be described. The reaction formula in a reactor for producing linoleic acid (C ₁₈ H ₃₂ O ₂ ) using carbon dioxide (CO ₂ ) and hydrogen (H ₂ ) as raw materials using potassium carbonate (K ₂ CO ₃ ) as a catalyst is as follows: [Chemical Formula 18] In this example, the reactor outlet temperature, ie, the reaction temperature, was set to 300 ° C., and the reactor outlet pressure, ie, the reaction pressure, was set to 2.0 MPa. If it is 300 degreeC, it is the temperature more than the normal boiling point of linoleic acid, and a suitable reaction rate will be obtained. If the pressure is 2.0 MPa, it is sufficiently smaller than the saturated vapor pressure at the temperature of the generated water vapor, so that a part of the water vapor does not condense into liquid water.

In the reaction of [Chemical Formula 18], the amount of heat ΔH ₃ (MJ / kmol) taken by the cooling water circulating on the tube side of the reactor is 3035.59 kJ per mol of linoleic acid to be produced. Then, by adjusting the flow rate F of the cooling water circulating on the tube side of the reactor so as to satisfy the above [Equation 3], the amount of heat ΔH ₃ can be taken while appropriately cooling the entire reactor.

The reaction in the condenser after the linoleic acid (C ₁₈ H ₃₂ O ₂ ) produced by the reaction of the above [Chemical Formula 18] and potassium hydrogen carbonate as a by-product is output from the reactor is the following [Chemical Formula 19]. ] Is as follows. Furthermore, after introducing and separating linoleic acid into a liquid-liquid separator, a reaction for regenerating potassium carbonate by introducing an aqueous potassium hydrogen carbonate solution into a solution regeneration tower is as shown in [Chemical Formula 20] below. In the regeneration of potassium carbonate, the reaction proceeds while removing the generated carbon dioxide, and the reaction shown in the above [Chemical Formula 20] is promoted to the production side.

  In addition, the reaction for removing excess water using a gas-liquid separator in order to contribute to the circulation of the potassium carbonate aqueous solution with respect to the potassium carbonate aqueous solution regenerated in the solution regeneration tower is as shown in the following [Chemical Formula 21].

In the following [Table 3], for the examples of individual aliphatic carboxylic acids, esters, aromatic carboxylic acids (C _n H _m O _l (l = 2)) produced according to the present invention The amount of heat ΔH deprived from, the heat of formation ΔHp of the hydrocarbon, the temperature condition of the reactor, and the pressure condition are shown respectively.

In addition, as examples of aliphatic carboxylic acids, esters, and aromatic carboxylic acids (C _n H _m O _l (l = 2)) that can be produced by applying the present invention, first, esters include methyl butyrate and ethyl formate. And ethyl butyrate, ethyl caproate, pentyl acetate, isopentyl acetate, pentyl valerate, pentyl butyrate, and octyl acetate. Examples of aromatics include catechol, guaiacol, 2-methoxy-4-methylphenol, eugenol and the like. And about aliphatic carboxylic acid, DHA, DPA, EPA etc. can be mentioned besides the substance quoted in [Table 3].

Example 4
In Example 4, a method for producing methyl salicylate represented by a carbon compound C _n H _m O _l (l = 3) will be described. The reaction formula in the reactor for producing methyl salicylate (C ₈ H ₈ O ₃ ) using carbon dioxide (CO ₂ ) and hydrogen (H ₂ ) as raw materials using potassium carbonate (K ₂ CO ₃ ) as a catalyst is as follows: [Chemical Formula 22] In this example, the reactor outlet temperature, ie, the reaction temperature, was set to 300 ° C., and the reactor outlet pressure, ie, the reaction pressure, was set to 2.0 MPa. If it is 300 degreeC, it is the temperature beyond the normal boiling point of methyl salicylate, and a suitable reaction rate will be obtained. If the pressure is 2.0 MPa, it is sufficiently smaller than the saturated vapor pressure at the temperature of the generated water vapor, so that a part of the water vapor does not condense into liquid water.

In the reaction of [Chemical Formula 22], the amount of heat ΔH ₄ (MJ / kmol) taken by the cooling water circulating on the tube side of the reactor is −480.88 kJ per mol of methyl salicylate to be produced. Then, by adjusting the flow rate F of the cooling water circulating on the tube side of the reactor so as to satisfy the above [Equation 3], the amount of heat ΔH ₄ can be taken while appropriately cooling the entire reactor. it can.

The reaction in the condenser after the methyl salicylate (C ₈ H ₈ O ₃ ) produced by the reaction of [Chemical Formula 22] and potassium hydrogen carbonate as a by-product are output from the reactor is represented by the following [Chemical Formula 23]. ] Is as follows. Furthermore, the reaction for regenerating potassium carbonate by introducing methyl salicylate into a liquid-liquid separator and then introducing an aqueous potassium hydrogen carbonate solution into a solution regeneration tower is as shown in [Chemical Formula 24] below. In the regeneration of potassium carbonate, the reaction proceeds while removing the generated carbon dioxide, and the reaction shown in the above [Chemical 24] is promoted to the production side.

  In addition, for the potassium carbonate aqueous solution regenerated in the solution regeneration tower, the reaction for removing excess water using a gas-liquid separator in order to contribute to the circulation of the potassium carbonate aqueous solution is as shown in [Chemical Formula 25] below.

In addition to the carbon compounds taken up in Examples 1 to 4 described above, the method for producing a carbon compound according to the present invention controls the cooling of the reactor so that the amount of heat ΔH calculated based on the generated heat ΔHp and the like is taken away. By doing so, it can be applied to the production of any carbon compound represented by C _n H _m O _l .

(Example 5)
In Example 5, a method for producing hexadecane (normal cetane: C ₁₆ H ₃₄ ), which is a liquid fuel, will be described. This is because, if high-purity normal cetane can be produced, it can be provided as a high-value-added light oil with excellent ignitability. For example, if normal cetane can be produced at a concentration of 100%, the light oil has a cetane number of 100 and the highest ignitability can be obtained. Conversely, 100% isocetane light oil has a cetane number of 15 and has the lowest ignitability. In JIS, since light oil is required to have a cetane number of 50 or more, it is theoretically assumed that 100% normal cetane produced according to the present invention is mixed 1: 1 with light oil having a cetane number of 50, It becomes a diesel oil with a cetane number of 75, and can be made very excellent in ignitability. Furthermore, sulfur, nitrogen and oxygen can be halved. Therefore, it is considered that the production of high purity normal cetane is very useful in applications for improving cetane number and reducing sulfur content. In the present specification, what is meant by “normal cetane” may be simply described as “cetane”.

The reaction formula in the reactor for producing normal cetane (C ₁₆ H ₃₄ ) using carbon dioxide (CO ₂ ) and hydrogen (H ₂ ) as raw materials using potassium carbonate (K ₂ CO ₃ ) as a catalyst is shown below. 26]. The reaction conditions in the reactor may be, for example, a reactor outlet temperature, that is, a reaction temperature of 300 ° C., and a reactor outlet pressure, that is, a reaction pressure of 2.0 MPa.

In the reaction of [Chemical Formula 26], the amount of heat ΔH ₅ (MJ / kmol) taken by the cooling water circulating on the tube side of the reactor is 2506.28 kJ per mol of normal cetane to be produced. Then, by adjusting the flow rate F of the cooling water circulating on the tube side of the reactor so as to satisfy the above [Equation 3], the heat amount ΔH ₅ can be taken away while appropriately cooling the entire reactor.

The reaction in the condenser after the normal cetane (C ₁₆ H ₃₄ ) produced by the reaction of the above [Chemical Formula 26] and potassium hydrogen carbonate as a by-product is output from the reactor is as shown in [Chemical Formula 27] below. It is. Further, after normal cetane is introduced and separated into a liquid-liquid separator, an aqueous potassium hydrogen carbonate solution is introduced into a solution regeneration tower. The reaction for regenerating potassium carbonate from an aqueous potassium hydrogen carbonate solution is as shown in the following [Chemical Formula 28]. In the regeneration of potassium carbonate, the reaction proceeds while removing the generated carbon dioxide, and the reaction shown in the above [Chemical 28] is promoted to the production side.

  In addition, for the potassium carbonate aqueous solution regenerated in the solution regeneration tower, the reaction for removing excess water using a gas-liquid separator is as shown in the following [Chemical 29] in order to contribute to the circulation use of the potassium carbonate aqueous solution.

INDUSTRIAL APPLICABILITY The present invention relates to an industrial carbon compound production method capable of efficiently obtaining a specific carbon compound, using as a model a reaction performed by a plant that produces vegetable oil using potassium carbonate as a catalyst and H ₂ and CO ₂ as reactants. Is built as. Then, the subject any carbon compounds represented by C _n H _m O _l, it is possible to proceed with the preparation efficiently. In particular, since a specific carbon compound is produced based on the heat of formation, only one (specific) isomer can be produced with high purity, for example, even if it is an isomer. Furthermore, since potassium carbonate is circulated and used, it is possible to proceed with extremely rational carbon compound production during continuous operation of the system (plant).

  Furthermore, as described above, the present invention can generate and use carbon dioxide and hydrogen, which are raw materials for producing a desired carbon compound, from a steam reforming process. As a result, for example, a steam reforming process using a carbon compound that is not highly evaluated due to reasons such as containing waste, low utility value, and low price (for example, the inventor has invented and applied for a patent) Carbon dioxide and hydrogen are produced based on the steam reforming process, etc., and the produced carbon dioxide and hydrogen are used as raw materials, and the carbon compound production method according to the present invention is applied to produce a carbon compound having a high desired value (for example, , Phenol, normal cetane, etc.) can be produced with high purity. If it does so, this invention may become a process with higher utility value than the GTL process of obtaining gasoline from natural gas as demonstrated in the background art column of this application.

Claims (6)

A carbon compound production method for producing a carbon compound containing at least carbon and hydrogen as constituent elements and, if necessary, oxygen.
Calculated based on the heat of formation of the carbon compound to be produced, the number of moles of carbon and the number of moles of oxygen in the carbon compound in a reactor under predetermined conditions, compressed water consisting of an aqueous potassium carbonate solution, carbon dioxide and hydrogen. The reaction is performed while cooling the reactor so as to take away the amount of heat ΔH, thereby generating the carbon compound, and the by-product is potassium hydrogen carbonate,
The said calorie | heat amount (DELTA) H is represented by following [Formula 1], The carbon compound manufacturing method characterized by the above-mentioned.

An aqueous solution of potassium hydrogen carbonate as the by-product was charged into a second reactor under reduced pressure as compared with the reaction in the reactor to produce an aqueous solution of carbon dioxide and potassium carbonate, and the produced dioxide dioxide. Regenerating the aqueous potassium carbonate solution while accelerating the reaction in the second reactor to the production side excluding carbon,
The carbon compound manufacturing method of Claim 1 characterized by the above-mentioned. Remove excess water from the regenerated potassium carbonate aqueous solution, pressurize the potassium carbonate aqueous solution from which the excess water has been removed, and use it as compressed water consisting of an aqueous potassium carbonate solution that functions as a reaction catalyst in the reactor.
The carbon compound manufacturing method of Claim 2 characterized by the above-mentioned. Adding to the reactor by spraying the compressed water;
The method for producing a carbon compound according to any one of claims 1 to 3, wherein: The carbon dioxide and the hydrogen are generated from a steam reforming process,
The method for producing a carbon compound according to any one of claims 1 to 4, wherein: The produced carbon compound consists only of a specific isomer,
The method for producing a carbon compound according to any one of claims 1 to 5, wherein:

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