JP2007238608A - Method for production of liquefied petroleum gas - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for economically producing a hydrocarbon material consisting mainly of propane and/or butane, namely a liquefied petroleum gas (LPG) from carbon-containing materials, such as natural gas, through synthesis gas, methanol and/or dimethyl ether. <P>SOLUTION: The method comprises producing the synthesis gas from the carbon-containing material, producing a crude methanol or crude dimethyl ether including carbon monoxide and/or carbon dioxide from the synthesis gas and producing the liquefied petroleum gas including hydrocarbons consisting mainly of propane or butane. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for producing liquefied petroleum gas whose main component is propane or butane from synthesis gas via methanol and / or dimethyl ether. Furthermore, the present invention relates to a method for producing a liquefied petroleum gas whose main component is propane or butane from a carbon-containing raw material such as natural gas via synthesis gas, methanol and / or dimethyl ether.

  The liquefied petroleum gas (LPG) is obtained by compressing a petroleum-based or natural gas-based hydrocarbon that is in a gaseous state at normal temperature and pressure, or by simultaneously cooling it into a liquid state, and its main component is propane or butane. LPG that can be stored and transported in a liquid state has excellent portability, and unlike natural gas that requires a pipeline for supply, it can be supplied to any place in a filled state in a cylinder. There is. For this reason, LPG mainly composed of propane, that is, propane gas, is widely used as a fuel for home use and business use. Currently, propane gas is supplied to approximately 25 million households (more than 50% of all households) in Japan. In addition to household and commercial fuels, LPG is also used as fuel for moving bodies (mainly butane gas) such as cassette stoves and disposable lighters, industrial fuel, and automobile fuel.

  Conventionally, LPG is obtained by 1) a method of recovering from wet natural gas, 2) a method of recovering from crude oil stabilization (vapor pressure adjustment), 3) a method of separating / extracting what is produced in an oil refining process, etc. Has been produced.

  Propane gas, which is used as a fuel for LPG, particularly for home and business use, is very useful if a new production method that can be industrially implemented can be established in the future.

As a method for producing LPG, Patent Document 1 discloses a methanol synthesis catalyst such as Cu—Zn, Cr—Zn, and Pd, specifically, a CuO—ZnO—Al ₂ O ₃ catalyst and a Pd / SiO ₂ catalyst. And a synthesis gas composed of hydrogen and carbon monoxide in the presence of a mixed catalyst obtained by physically mixing a zeolite having an average pore diameter of approximately 10 mm (1 nm) or more, specifically, a methanol conversion catalyst composed of Y-type zeolite. A method of reacting to produce liquefied petroleum gas or a hydrocarbon mixture having a composition close to this is disclosed.

As a method for producing LPG, Non-Patent Document 1 discloses that 4 wt% Pd / SiO ₂ , a Cu—Zn—Al mixed oxide [Cu: Zn: Al = 40: 23: 37 (atom), which is a catalyst for methanol synthesis. Ratio)] or a Cu-based catalyst for low-pressure methanol synthesis (trade name: BASF S3-85) and high-silica Y-type zeolite with SiO ₂ / Al ₂ O ₃ = 7.6 treated with steam at 450 ° C. for 1 hour. And a method for producing C2-C4 paraffins from synthesis gas via methanol and dimethyl ether with a selectivity of 69-85%.

On the other hand, Non-Patent Document 2 discloses a method for producing LPG using at least one of methanol and dimethyl ether as a raw material. Specifically, under slight pressure, at a reaction temperature of 603 K (330 ° C.), a raw material gas of methanol: H ₂ : N ₂ = 1: 1: 1 has a methanol-based LHSV of 20 h ⁻¹ , and the first stage is ZSM-5 And two catalyst layers (ZSM-5 / Pt-C Series) whose subsequent stage is Pt-C, or a mixed catalyst layer (ZSM-5 / Pt-C Pellet) composed of ZSM-5 and Pt-C. -Mixture) to carry out the LPG synthesis reaction.

Furthermore, Non-Patent Document 3 discloses a method for producing LPG from dimethyl ether and hydrogen by catalytic reaction. As the catalyst to be used, a hybrid catalyst composed of a methanol synthesis catalyst and zeolite (Cu-Zn / USY etc.), ZSM-5 ion-exchanged with Pd (Pd-ZSM-5), ZSM-5 ion-exchanged with Pt (Pt -ZSM-5) and the like. Non-Patent Document 4 also discloses VIIIB metal-supported ZSM-5 as a catalyst, specifically, ZSM-5 ion-exchanged with Pd (Pd-ZSM-5), ZSM-5 ion-exchanged with Pt (Pt-ZSM- 5) and the like, and a method for producing LPG from dimethyl ether and hydrogen is disclosed.
Japanese Patent Laid-Open No. 61-23688 “Selective Synthesis of LPG from Synthesis Gas”, Kaoru Fujimoto et al. Bull. Chem. Soc. Jpn. 58, p. 3059-3060 (1985) “Methanol / Dimethyl Ether Conversion on Zeolites Catalysts for Indirect Synthesis of LPG from Natural Gas”, Yingjie Jin et al. , 92nd Catalyst Conference, Proceedings of Conference A, p. 322, September 18, 2003 “Selective Synthesis of LPG from DME”, Kenji Asami et al. , The 47th Annual Meeting of the Petroleum Society, 53rd Research Presentation Abstract, p. 98-99, May 19, 2004 “Synthesis of LPG from DME with VIIIB Metal Supported on ZSM-5”, Kenji Asami et al. , 13th Annual Meeting of the Japan Institute of Energy, p. 128-129, July 29, 2004

  An object of the present invention is to provide a method capable of economically producing a hydrocarbon whose main component is propane or butane, that is, liquefied petroleum gas (LPG), from methanol and / or dimethyl ether from synthesis gas. It is to be.

  Another object of the present invention is to economically produce hydrocarbons whose main component is propane or butane, that is, liquefied petroleum gas (LPG), from a carbon-containing raw material such as natural gas, via synthesis gas, methanol and / or dimethyl ether. It is to provide a method that can be manufactured automatically.

According to the present invention,
(I) a methanol production process for producing crude methanol containing methanol, hydrogen, and at least one of carbon monoxide and carbon dioxide from synthesis gas using a methanol synthesis catalyst;
(Ii) Liquefaction in which crude methanol obtained in the methanol production process is supplied without purification, and liquefied petroleum gas in which the main component of the contained hydrocarbon is propane or butane is produced using a catalyst for liquefied petroleum gas production. There is provided a method for producing a liquefied petroleum gas, comprising a petroleum gas production process.

Furthermore, according to the present invention,
(I) a synthesis gas production process for producing synthesis gas from a carbon-containing raw material and at least one selected from the group consisting of H ₂ O, O ₂ and CO ₂ ;
(II) a methanol production process for producing crude methanol containing methanol, hydrogen, and at least one of carbon monoxide and carbon dioxide from synthesis gas using a methanol synthesis catalyst;
(III) Liquefaction in which crude methanol obtained in the methanol production process is supplied without purification, and liquefied petroleum gas in which the main component of the contained hydrocarbon is propane or butane is produced using a catalyst for liquefied petroleum gas production. There is provided a method for producing a liquefied petroleum gas, comprising a petroleum gas production process.

Moreover, according to the present invention,
(I) a dimethyl ether production process for producing crude dimethyl ether containing dimethyl ether, hydrogen, and at least one of carbon monoxide and carbon dioxide from synthesis gas using a dimethyl ether synthesis catalyst;
(Ii) Liquefaction by supplying the crude dimethyl ether obtained in the dimethyl ether production process without purification and using the catalyst for liquefied petroleum gas production to produce liquefied petroleum gas whose main hydrocarbon component is propane or butane. There is provided a method for producing a liquefied petroleum gas, comprising a petroleum gas production process.

Furthermore, according to the present invention,
(I) a synthesis gas production process for producing synthesis gas from a carbon-containing raw material and at least one selected from the group consisting of H ₂ O, O ₂ and CO ₂ ;
(II) a dimethyl ether production process for producing crude dimethyl ether containing dimethyl ether, hydrogen, and at least one of carbon monoxide and carbon dioxide from synthesis gas using a dimethyl ether synthesis catalyst;
(III) Liquefaction that supplies crude dimethyl ether obtained in the dimethyl ether production process without purification and uses the catalyst for liquefied petroleum gas production to produce liquefied petroleum gas whose main hydrocarbon component is propane or butane. There is provided a method for producing a liquefied petroleum gas, comprising a petroleum gas production process.

  Here, the synthesis gas refers to a mixed gas containing hydrogen and carbon monoxide produced from a carbon-containing raw material such as natural gas or coal, and is not limited to a mixed gas consisting of hydrogen and carbon monoxide. The synthesis gas may be a mixed gas containing, for example, carbon dioxide, water, methane, ethane, ethylene, and the like. Syngas obtained by reforming natural gas usually contains carbon dioxide and water vapor in addition to hydrogen and carbon monoxide.

  In the present invention, first, methanol and / or dimethyl ether is produced from synthesis gas. Next, methanol and / or dimethyl ether and hydrogen are reacted in the presence of a catalyst for producing liquefied petroleum gas to produce a hydrocarbon whose main component is propane or butane, that is, liquefied petroleum gas (LPG). The liquefied petroleum gas production catalyst used contains an olefin hydrogenation catalyst component such as Fe, Co, Ni, Cu, Zn, Ru, Rh, Pd, Ir, and Pt, and zeolite. For example, Pd and / or Alternatively, Pt is supported on ZSM-5 or USY-type zeolite, and Pd-based catalyst component obtained by supporting Pd on a support (such as silica) and USY-type zeolite are mixed.

  When methanol is produced from synthesis gas, carbon monoxide and hydrogen are reacted in the presence of a methanol synthesis catalyst. The product (unpurified methanol) obtained by this reaction usually contains water, carbon monoxide as an unreacted raw material, carbon dioxide as a by-product, dimethyl ether, and the like.

  On the other hand, when producing dimethyl ether from synthesis gas, carbon monoxide and hydrogen are reacted in the presence of a dimethyl ether synthesis catalyst which is a mixed catalyst of a methanol synthesis catalyst and a methanol dehydration catalyst. The product (unpurified dimethyl ether) obtained by this reaction usually contains water, carbon monoxide as an unreacted raw material, carbon dioxide as a by-product, methanol, and the like.

  When constructing a process for producing methanol and / or dimethyl ether from synthesis gas and subsequently producing LPG from methanol and / or dimethyl ether, it is necessary to purify the product after the synthesis reaction of methanol and / or dimethyl ether. It is economically disadvantageous because of the large number and energy consumption for purification. It is highly desirable from the viewpoint of economy that unpurified methanol and / or unpurified dimethyl ether can be used as a raw material gas for LPG production (gas fed to the reactor).

  By the way, conventionally, a method for producing an olefin from methanol and / or dimethyl ether is well known. The hydrogenation reaction of olefins to paraffin is also well known. By combining the two, LPG can be produced from methanol and / or dimethyl ether. Specifically, first, an olefin having a main component of propylene or butene is produced from methanol and / or dimethyl ether using a zeolite catalyst, and then the obtained olefin is hydrogenated using an olefin hydrogenation catalyst. To produce paraffins whose main component is propane or butane, that is, LPG.

  However, in this LPG production method in which the reaction is performed in two steps, it is difficult to say that the zeolite catalyst is easily deteriorated by coking in the process of synthesizing olefins from methanol and / or dimethyl ether, and the catalyst life is sufficiently long.

  Furthermore, in this LPG production method, it is not desirable that the raw material gas contains carbon monoxide and / or carbon dioxide. When the raw material gas contains carbon monoxide and / or carbon dioxide, carbon monoxide and carbon dioxide may become catalyst poisons in the second stage olefin hydrogenation process, and LPG can be stabilized over a long period of time. It is difficult to manufacture. Also, methane may be produced by hydrogenation. That is, in many cases, in the LPG production method in which the reaction is performed in two steps, unpurified methanol and / or unpurified dimethyl ether containing carbon monoxide, carbon dioxide, and the like cannot be used as a raw material gas for LPG production.

  On the other hand, in the LPG production method of the present invention in which LPG is synthesized from methanol and / or dimethyl ether in one step, there is no influence on LPG synthesis even if the raw material gas contains carbon monoxide and / or carbon dioxide. Even when a catalyst containing an olefin hydrogenation catalyst component is used in the LPG synthesis reaction, there is no problem like the LPG production method in which the reaction is carried out in the above two steps. Therefore, in the present invention, unpurified methanol and unpurified dimethyl ether containing carbon monoxide, carbon dioxide and the like, produced from synthesis gas, can be used as a raw material gas for LPG production.

  Furthermore, according to the method for producing LPG of the present invention, even when a catalyst containing zeolite is used in the LPG synthesis reaction, deterioration due to zeolite coking is small, and LPG can be produced stably over a long period of time. Catalyst costs are also reduced.

  Thus, according to the present invention, a hydrocarbon whose main component is propane or butane, that is, LPG can be economically produced from synthesis gas via methanol and / or dimethyl ether. In addition, according to the present invention, a hydrocarbon whose main component is propane or butane, that is, LPG is economically produced from a carbon-containing raw material such as natural gas via synthesis gas, methanol and / or dimethyl ether. Can do.

  An embodiment of the LPG production method of the present invention will be described with reference to the drawings.

  FIG. 1 shows an example of an LPG production apparatus suitable for carrying out the LPG production method of the present invention.

  First, natural gas (methane) is supplied to the reformer 11 via the line 21 as a carbon-containing raw material. Although not shown, oxygen, water vapor, or carbon dioxide is supplied to the line 21 as necessary. In the reformer 11, a reforming catalyst (synthetic gas production catalyst) 11a is provided. The reformer 11 includes a heating unit (not shown) for supplying heat necessary for reforming. In the reformer 11, methane is reformed in the presence of the reforming catalyst, and a synthesis gas containing hydrogen and carbon monoxide is obtained.

  The synthesis gas thus obtained is supplied to the methanol synthesis reactor 12 via a line 22. In the reactor 12, a methanol synthesis catalyst 12a is provided. In this reactor 12, crude methanol containing methanol, hydrogen, carbon monoxide and / or carbon dioxide is produced from synthesis gas in the presence of a methanol synthesis catalyst.

  The produced crude methanol is supplied to the liquefied petroleum gas production reactor 13 via the line 23 without being purified. Although not shown, hydrogen is supplied to the line 23 as necessary. Inside the reactor 13, a liquefied petroleum gas production catalyst 13a is provided. In the reactor 13, hydrocarbon gas (lower paraffin-containing gas) whose main component is propane or butane is produced from crude methanol in the presence of a liquefied petroleum gas production catalyst.

  The produced hydrocarbon gas is removed by moisture, low-boiling components such as hydrogen and high-boiling components by gas-liquid separation or the like, and then pressurized and cooled to obtain LPG as a product from the line 24. It is done.

  Although not shown, the LPG manufacturing apparatus is provided with a booster, a heat exchanger, a valve, an instrumentation control device, and the like as necessary.

  Further, a dimethyl ether synthesis catalyst can be used instead of the methanol synthesis catalyst 12a. In that case, crude dimethyl ether containing dimethyl ether, hydrogen, carbon monoxide and / or carbon dioxide is produced from synthesis gas in the reactor 12, and from this, the main component is propane or butane in the reactor 13. Hydrocarbon gas (lower paraffin-containing gas) is produced.

[Syngas production process]
In the synthesis gas production process, synthesis gas is usually produced from a carbon-containing raw material and at least one selected from the group consisting of H ₂ O, O ₂ and CO ₂ .

As the carbon-containing raw material, a substance containing carbon and capable of generating H ₂ and CO by reacting with at least one selected from the group consisting of H ₂ O, O ₂ and CO ₂ can be used. . As the carbon-containing raw material, those known as raw materials for synthesis gas can be used. For example, lower hydrocarbons such as methane and ethane, natural gas, naphtha, coal, and the like can be used.

  In the present invention, since a catalyst is usually used in a synthesis gas production process, a methanol production process or a dimethyl ether production process, and a liquefied petroleum gas production process, as a carbon-containing raw material (natural gas, naphtha, coal, etc.), sulfur, sulfur compounds, etc. Those having a low content of the catalyst poisoning substance are preferred. Moreover, when a catalyst poisoning substance is contained in the carbon-containing raw material, a step of removing the catalyst poisoning substance such as desulfurization can be performed prior to the synthesis gas production process, if necessary.

The synthesis gas reacts the carbon-containing raw material as described above with at least one selected from the group consisting of H ₂ O, O ₂ and CO _{2 in} the presence of a synthesis gas production catalyst (reforming catalyst). It is manufactured by. The synthesis gas is produced by a known method, for example, a steam reforming method, a combined reforming method, or an autothermal reforming method of natural gas (methane).

From the stoichiometry for methanol production as shown in the following formula (1), the composition of the synthesis gas is preferably H ₂ / CO (molar ratio) = 2.

When methanol is mainly produced from synthesis gas, the composition of the synthesis gas produced in the synthesis gas production process is preferably CO: H ₂ = 1: 1.5 to 1: 2.5 (molar ratio). The content ratio of hydrogen to carbon monoxide (H ₂ / CO; molar basis) in the produced synthesis gas is preferably 1.8 or more, and more preferably 1.9 or more. In addition, the content ratio of hydrogen to carbon monoxide (H ₂ / CO; on a molar basis) in the produced synthesis gas is preferably 2.3 or less, and more preferably 2.2 or less. By setting the composition of the synthesis gas in the above range, methanol can be produced more efficiently and more economically in the next methanol production process, and as a result, LPG can be produced more economically. it can.

Further, as expressed by the following formula (2), the composition of the synthesis gas is preferably H ₂ / CO (molar ratio) = 1 in terms of the stoichiometry for producing dimethyl ether.

When mainly producing dimethyl ether from synthesis gas, the composition of the synthesis gas produced in the synthesis gas production process is preferably CO: H ₂ = 1: 0.5 to 1: 1.5 (molar ratio). The content ratio of hydrogen to carbon monoxide (H ₂ / CO; on a molar basis) in the produced synthesis gas is preferably 0.8 or more, and more preferably 0.9 or more. Further, the content ratio of hydrogen to carbon monoxide (H ₂ / CO; on a molar basis) in the produced synthesis gas is preferably 1.2 or less, and more preferably 1.1 or less. By setting the composition of the synthesis gas within the above range, dimethyl ether can be produced more efficiently and more economically in the next dimethyl ether production process, and as a result, LPG can be produced more economically. it can.

Further, for example, a shift reactor is provided downstream of a reformer that is a reactor for producing synthesis gas from the above raw materials, and the composition of the synthesis gas is changed by the shift reaction (CO + H ₂ O → CO ₂ + H ₂ ). It is also possible to adjust to the range.

  In order to produce a synthesis gas having a composition within the above range, a supply ratio of a carbon-containing raw material and at least one selected from the group consisting of water, steam and oxygen, and a catalyst for producing a synthesis gas to be used And other reaction conditions may be appropriately selected.

  The synthesis gas whose composition is in the above range can be produced, for example, by the following method.

In the presence of a reforming catalyst comprising a composite oxide having a composition represented by the following formula (A), a carbon-containing raw material (particularly natural gas, methane), oxygen, carbon dioxide, and steam (steam) are reacted in a reactor. (Carbon dioxide + steam) / carbon ratio in the raw material gas introduced into the reactor is 0.5-3, oxygen / carbon ratio is 0.2-1 and the temperature at the outlet of the reactor is 900-1100 ° C., pressure Can be made to react at 5 to 60 kg / cm ² to produce the synthesis gas used in the present invention.

_{M a · Co b · Ni c} · Mg d · Ca e · O f (A)
(Wherein M is selected from the group consisting of Group 6A elements, Group 7A elements, Group 8 transition elements excluding Co and Ni, Group 1B elements, Group 2B elements, Group 4B elements, and lanthanoid elements) Represents at least one element, a, b, c, d and e represent the atomic ratio of each element, and when a + b + c + d + e = 1, 0 ≦ a ≦ 0.1, 0.001 ≦ (b + c) ≦ 0. 3, 0 ≦ b ≦ 0.3, 0 ≦ c ≦ 0.3, 0.6 ≦ (d + e) ≦ 0.999, 0 <d ≦ 0.999, 0 ≦ e ≦ 0.999, and f is (Each element is necessary to maintain charge balance with oxygen.)
The (carbon dioxide + steam) / carbon ratio in the raw material gas introduced into the reactor is preferably about 0.5 to 2. The temperature at the outlet of the reactor is preferably 950 to 1050 ° C. The pressure at the outlet of the reactor is preferably 15 to 20 kg / cm ² .

The space velocity of the raw material gas is usually 500～200000Hr ^-1, preferably 1000~100000hr ^-1, 1000~70000hr ^-1 are more preferred.

  The composite oxide having the composition represented by the above formula (A) is a kind in which MgO and CaO have a rock salt type crystal structure, and a part of Mg or Ca atoms located in the lattice is substituted with Co, Ni or M It is a solid solution and forms a single phase.

  In the above formula (A), M is at least one element selected from the group consisting of manganese, molybdenum, rhodium, ruthenium, platinum, palladium, copper, silver, zinc, tin, lead, lanthanum and cerium. preferable.

  The M content (a) is 0 ≦ a ≦ 0.1, preferably 0 ≦ a ≦ 0.05, and more preferably 0 ≦ a ≦ 0.03. If the M content (a) exceeds 0.1, the activity of the reforming reaction decreases.

  The cobalt content (b) is 0 ≦ b ≦ 0.3, preferably 0 ≦ b ≦ 0.25, and more preferably 0 ≦ b ≦ 0.2. When the cobalt content (b) exceeds 0.3, it is difficult to sufficiently obtain the carbonaceous precipitation preventing effect.

  The nickel content (c) is 0 ≦ c ≦ 0.3, preferably 0 ≦ c ≦ 0.25, and more preferably 0 ≦ c ≦ 0.2. If the nickel content (c) exceeds 0.3, it is difficult to sufficiently obtain the carbonaceous precipitation preventing effect.

  The total amount (b + c) of the cobalt content (b) and the nickel content (c) is 0.001 ≦ (b + c) ≦ 0.3, and 0.001 ≦ (b + c) ≦ 0.25. It is preferable that 0.001 ≦ (b + c) ≦ 0.2. When the total content (b + c) exceeds 0.3, it becomes difficult to sufficiently obtain the carbonaceous precipitation preventing effect. On the other hand, when the total content (b + c) is less than 0.001, the reaction activity decreases.

  The total amount (d + e) of the magnesium content (d) and the calcium content (e) is 0.6 ≦ (d + e) ≦ 0.9998, and 0.7 ≦ (d + e) ≦ 0.9998. Preferably, 0.77 ≦ (d + e) ≦ 0.9998 is more preferable.

  Among these, the magnesium content (d) is 0 <d ≦ 0.999, preferably 0.2 ≦ d ≦ 0.9998, and more preferably 0.37 ≦ d ≦ 0.9998. . The calcium content (e) is 0 ≦ e <0.999, preferably 0 ≦ e ≦ 0.5, and more preferably 0 ≦ e ≦ 0.3. This catalyst may not contain calcium.

  The total amount (d + e) of the magnesium content (d) and the calcium content (e) is determined by the balance of the M content (a), the cobalt content (b), and the nickel content (c). (D + e) exhibits an excellent effect on the reforming reaction at any ratio within the above range. However, if the contents of calcium (e) and M (a) are large, the effect of suppressing carbonaceous precipitation is high. Although it exists, there exists a tendency for a catalyst activity to become low compared with the case where there is much magnesium (d). From the viewpoint of activity, it is preferable that the calcium content (e) is 0.5 or less and the M content (a) is 0.1 or less.

  The reforming catalyst to be used is preferably such that at least one of M, Co and Ni is highly dispersed in the composite oxide. Here, the dispersion is defined as the ratio of the number of atoms exposed on the catalyst surface to the total number of atoms of the supported metal. That is, if the number of atoms of a metal element of Co, Ni or M or a compound thereof is A and the number of atoms exposed on the particle surface among these atoms is B, B / A is the dispersity. By using a reforming catalyst in which at least one of M, Co, and Ni is highly dispersed in the composite oxide, the reaction becomes more active and the reaction proceeds stoichiometrically. Is more effectively prevented.

  Examples of a method for producing such a reforming catalyst include an impregnation support method, a coprecipitation method, a sol-gel method (hydrolysis method), and a uniform precipitation method.

  The above reforming catalyst is usually subjected to an activation treatment before being used for the production of synthesis gas. In the activation treatment, the catalyst is heated in the temperature range of 500 to 1000 ° C., preferably 600 to 1000 ° C., more preferably 650 to 1000 ° C. for about 0.5 to 30 hours in the presence of a reducing gas such as hydrogen gas. To do. The reducing gas may be diluted with an inert gas such as nitrogen gas. This activation treatment can also be performed in a reactor that performs the reforming reaction. By this activation treatment, catalytic activity is expressed.

As another method for producing the synthesis gas used in the present invention, a mixed gas having a temperature of at least 600 ° C. containing the unreacted carbon-containing raw material by partially oxidizing a carbon-containing raw material (particularly natural gas, methane). Then, the unreacted carbon-containing raw material contained in the high-temperature mixed gas is supported on a carrier made of a metal oxide having a metal ion electronegativity of 13 or less, rhodium, ruthenium, iridium, palladium and platinum. A specific surface area of 25 m ² / g or less in which at least one metal (catalyst metal) selected from the group consisting of: And a method of producing a synthesis gas by reacting carbon dioxide gas and / or steam under a pressurized condition in the presence of 1 mol% of a catalyst. Further, a mixed gas composed of a carbon-containing raw material (particularly natural gas, methane), an oxygen-containing gas (air, oxygen, etc.), carbon dioxide gas and / or steam is used, and the electronegativity of metal ions is 13 or less. A specific surface area of 25 m ² / g or less, a supported amount of catalyst metal, in which at least one metal (catalyst metal) selected from the group consisting of rhodium, ruthenium, iridium, palladium and platinum is supported on a support made of a certain metal oxide. In the presence of 0.0005 to 0.1 mol% of the catalyst in terms of metal in the amount of metal, the carbon-containing raw material in the mixed gas is partially oxidized to include an unreacted carbon-containing raw material. A mixed gas having a temperature of at least 600 ° C. is generated, and a carbon dioxide gas and / or steam is reacted with the unreacted carbon-containing raw material under pressurized conditions to produce a synthesis gas. How to, and the like.

  Here, the catalyst metal may be supported in a metal state, or may be supported in the state of a metal compound such as an oxide. Further, the metal oxide used as the carrier may be a single metal oxide or a composite metal oxide.

  The electronegativity of metal ions in the metal oxide for support is 13 or less, preferably 12 or less, and more preferably 10 or less. When the electronegativity of the metal ion in the metal oxide exceeds 13, carbon deposition becomes remarkable when the catalyst is used. Moreover, the lower limit of the electronegativity of metal ions in the metal oxide for support is usually about 4.

  In addition, the electronegativity of the metal ion in the metal oxide is defined by the following formula.

Xi = (1 + 2i) Xo
Xi: Electronegativity of metal ions,
Xo: metal electronegativity,
i: the number of valence electrons of the metal ion.

  When the metal oxide is a composite metal oxide, the average metal ion electronegativity is used, and the value is calculated based on the electronegativity of each metal ion contained in the composite metal oxide. The sum of the product multiplied by the mole fraction of the product.

  Pauling's electronegativity is used for the metal electronegativity (Xo). Pauling's electronegativity is described in Table 15.4 of “Ryoichi Fujishiro, Moore Physical Chemistry (4th edition), Tokyo Kagaku Dojin, p.707 (1974)”. The electronegativity (Xi) of metal ions in the metal oxide is described in detail, for example, in “Catalyst Society, Catalyst Course, Vol. 2, p. 145 (1985)”.

Examples of such metal oxides include metal oxides containing one or more metals such as Mg, Ca, Ba, Zn, Al, Zr, and La. Specific examples of such metal oxides include magnesia (MgO), calcium oxide (CaO), barium oxide (BaO), zinc oxide (ZnO), alumina (Al ₂ O ₃ ), zirconia (ZrO ₂ ), Single metal oxides such as lanthanum oxide (La ₂ O ₃ ), MgO / CaO, MgO / BaO, MgO / ZnO, MgO / Al ₂ O ₃ , MgO / ZrO ₂ , CaO / BaO, CaO / ZnO, CaO / Al ₂ O ₃ , CaO / ZrO ₂ , BaO / ZnO, BaO / Al ₂ O ₃ , BaO / ZrO ₂ , ZnO / Al ₂ O ₃ , ZnO / ZrO ₂ , Al ₂ O ₃ / ZrO ₂ , La ₂ O Examples thereof include composite metal oxides such as ₃ / MgO, La ₂ O ₃ / Al ₂ O ₃ , and La ₂ O ₃ / CaO.

Used specific surface area of the catalyst is not more than ^{25 m} 2 / g, preferably not more than ^{20 m} 2 / g, more preferably not more than ^{15m 2 / g, 10m 2 /} g or less is particularly preferred. Moreover, the lower limit of the specific surface area of the catalyst used is usually about 0.01 m ² / g. By setting the specific surface area of the catalyst within the above range, the carbon deposition activity of the catalyst can be more sufficiently suppressed.

In the catalyst used here, the specific surface area of the catalyst and the specific surface area of the metal oxide as a support are substantially the same. Therefore, the specific surface area of the metal oxide is a carrier is less ^{25 m} 2 / g, preferably not more than ^{20 m} 2 / g, more preferably not more than ^{15m 2 / g, 10m 2 /} g or less is particularly preferred. Moreover, the lower limit of the specific surface area of the metal oxide as a support is usually about 0.01 m ² / g.

  Here, the specific surface area of the metal oxide as a catalyst or a carrier is measured at a temperature of 15 ° C. by the BET method.

The catalyst having a specific surface area of 25 m ² / g or less is obtained by calcining a metal oxide as a support at 300 to 1300 ° C., preferably 650 to 1200 ° C. before supporting the catalyst metal, and after the catalyst metal is supported, It can be obtained by further firing the support at 600 to 1300 ° C, preferably 650 to 1200 ° C. Further, after the catalyst metal is supported on the metal oxide as the carrier, the obtained catalyst metal support can be obtained by firing at 600 to 1300 ° C, preferably 650 to 1200 ° C. By controlling the calcination temperature and the calcination time, the specific surface area of the metal oxide which is the catalyst or the support obtained can be controlled.

  The amount of the catalyst metal supported on the metal oxide as the support is 0.0005 to 0.1 mol% in terms of metal. The amount of the catalyst metal supported on the metal oxide as the carrier is preferably 0.001 mol% or more, and more preferably 0.002 mol% or more, in terms of metal. Further, the supported amount of the catalyst metal with respect to the metal oxide as the carrier is preferably 0.09 mol% or less in terms of metal.

  The catalyst as described above has a small specific surface area of the catalyst and a very small amount of the catalyst metal supported, so that it has a sufficient synthesis gasification activity for the carbon-containing raw material, and the carbon deposition activity is remarkably suppressed. It is a thing.

  Such a catalyst can be prepared according to a known method. As a method for producing a catalyst, for example, a metal oxide as a support is dispersed in water, a catalyst metal salt or an aqueous solution thereof is added and mixed, and then the metal oxide on which the catalyst metal is supported is separated from the aqueous solution. Drying and firing method (impregnation method) or exhausting the metal oxide as the carrier, adding a small amount of metal salt solution for the pore volume to make the surface of the carrier evenly wet, then drying and firing The method (incipient-wetness method) etc. are mentioned.

  The synthesis gas used in the present invention can be produced by reacting a carbon-containing raw material (particularly natural gas, methane) with steam (water vapor) and / or carbon dioxide in the presence of the catalyst as described above. .

In the case of a method of reacting a carbon-containing raw material and carbon dioxide (CO ₂ reforming), the reaction temperature is 500 to 1200 ° C, preferably 600 to 1000 ° C. The reaction pressure is 5 to 40 kg / cm ² G, preferably 5 to 30 kg / cm ² G. When performing the reaction in a fixed bed system, a gas hourly space velocity (GHSV) is 1,000~10,000hr ^-1, 2,000~8,000hr ^-1 are preferred. The content of CO _{2 in} the raw material gas introduced into the reactor is _{20 to} 0.5 mol of CO ₂ per 1 mol of carbon in the carbon-containing raw material, and preferably 10 to 1 mol.

In the case of a method of reacting the carbon-containing raw material and steam (steam reforming), the reaction temperature is 600 to 1200 ° C, preferably 600 to 1000 ° C. The reaction pressure is 1 to 40 kg / cm ² G, preferably 5 to 30 kg / cm ² G. When performing the reaction in a fixed bed system, a gas hourly space velocity (GHSV) is 1,000~10,000hr ^-1, 2,000~8,000hr ^-1 are preferred. The content of steam in the raw material gas introduced into the reactor is 20 to 0.5 mol of steam (H ₂ O) per 1 mol of carbon in the carbon-containing raw material, preferably 10 to 1 mol, and 1.5 ˜1 mole is more preferred.

When a synthesis gas is produced by reacting a mixture of steam and CO ₂ with a carbon-containing raw material, the mixing ratio of steam and CO ₂ is not particularly limited, but usually the H ₂ O / CO ₂ (molar ratio) is 0. 1-10.

  In this synthesis gas production method, the energy required for the reforming reaction is caused by partial oxidation (partial combustion) of the carbon-containing raw material that is the reaction raw material for reforming, and the combustion heat generated at that time. To be replenished.

The partial oxidation reaction of the carbon-containing raw material is performed under conditions of a temperature of 600 to 1500 ° C., preferably 700 to 1300 ° C., and a pressure of 5 to 50 kg / cm ² G, preferably 10 to 40 kg / cm ² G. Oxygen is used as an oxidizing agent for partially oxidizing the carbon-containing raw material. As this oxygen source, oxygen-containing gas such as air or oxygen-enriched air is used in addition to pure oxygen. The content of oxygen in the raw material gas introduced into the reactor is 0.1 to 4, preferably 0.5 to 2, in terms of the atomic ratio (O / C) of oxygen to carbon in the carbon-containing raw material.

  By this partial oxidation of the carbon-containing raw material, a high-temperature mixed gas containing at least 600 ° C., preferably 700 to 1300 ° C., containing the unreacted carbon-containing raw material is obtained. A synthesis gas can be produced by reacting carbon dioxide and / or steam under the above conditions with the unreacted carbon-containing raw material in the mixed gas. Carbon dioxide and / or steam may be added to and reacted with the mixed gas obtained by partial oxidation of the carbon-containing raw material, or may be added and mixed in advance with the carbon-containing raw material used for the partial oxidation reaction. Good. In the latter case, the partial oxidation of the carbon-containing raw material and the reforming reaction can be performed simultaneously.

  The reforming reaction of the carbon-containing raw material can be carried out in various types of reactors, but usually it is preferably carried out in a fixed bed system or a fluidized bed system.

[Methanol production process, dimethyl ether production process]
In the present invention, by reacting carbon monoxide and hydrogen in the presence of a catalyst, methanol, hydrogen, carbon monoxide and / or carbon dioxide are synthesized from the synthesis gas obtained in the above synthesis gas production process. Crude methanol containing, or crude dimethyl ether containing dimethyl ether, hydrogen, carbon monoxide and / or carbon dioxide is produced.

  Next, this process (methanol production process) in the case of mainly producing methanol from synthesis gas and this process (dimethyl ether production process) in the case of producing dimethyl ether mainly from synthesis gas will be described.

[Methanol production process]
In the methanol production process, methanol (crude methanol) is produced from the synthesis gas obtained in the synthesis gas production process by reacting carbon monoxide and hydrogen in the presence of a methanol synthesis catalyst. The crude methanol produced here contains unreacted raw material carbon monoxide and by-product carbon dioxide.

  The gas fed into the reactor in the methanol production process may be a gas obtained by separating predetermined components such as moisture and carbon dioxide from the synthesis gas obtained in the synthesis gas production process. The water and carbon dioxide separated here can be recycled to the synthesis gas production process.

  In this methanol production process, methanol can be produced according to a known method, for example, by the following method.

  Methanol synthesis can be performed by a gas phase reaction or a liquid phase reaction in which a methanol synthesis catalyst is dispersed in an inert solvent. In the case of a liquid phase reaction (slurry method), examples of the solvent include petroleum solvents, and the amount of methanol synthesis catalyst used can be, for example, about 25 to 50% by weight.

  Examples of the fixed bed catalytic synthesis reactor include a quench reactor, a multi-tube reactor, a multi-stage reactor, a multi-stage cooling radial flow reactor, a double-tube heat exchange reactor, and a cooling coil built-in system. Or a mixed flow type reactor can be used.

  As the methanol synthesis catalyst, a known methanol synthesis catalyst, specifically, a Cu-Zn catalyst such as copper oxide-zinc oxide, copper oxide-zinc oxide-aluminum oxide (alumina), copper oxide-zinc oxide-chromium oxide, etc. And Zn-Cr-based catalysts such as zinc oxide-chromium oxide and zinc oxide-chromium oxide-alumina, and Cu-ZnO-based catalysts. Further, as a methanol synthesis catalyst having high durability in a relatively high concentration carbon dioxide atmosphere, Cu, Zn, Al, Ga, and M (at least one element selected from alkaline earth metal elements and rare earth elements) are used. , Cu: Zn: Al: Ga: M = 100: 10 to 200: 1 to 20: 1 to 20: 0.1 to 20 (atomic ratio).

  The methanol synthesis catalyst may contain other additional components as necessary within the range not impairing the desired effect.

The gas fed into the reactor is preferably a synthesis gas containing carbon monoxide and hydrogen at CO: H ₂ = 1: 1.5 to 1: 2.5 (molar ratio). The content ratio of hydrogen to carbon monoxide (H ₂ / CO; on a molar basis) in the gas fed to the reactor is more preferably 1.8 or more, and particularly preferably 1.9 or more. In addition, the content ratio of hydrogen to carbon monoxide (H ₂ / CO; on a molar basis) in the gas fed to the reactor is more preferably 2.3 or less, and particularly preferably 2.2 or less.

  The gas fed into the reactor may contain components other than carbon monoxide and hydrogen, and it may be preferable to contain carbon dioxide. For example, the carbon dioxide content in the gas fed into the reactor can be 0.1 to 15 mol%.

  When a Cu—Zn-based catalyst is used as the methanol synthesis catalyst, the reaction temperature can be about 200 to 300 ° C. The reaction pressure can be about 1 to 10 MPa.

  When a Zn—Cr-based catalyst is used as the methanol synthesis catalyst, the reaction temperature can be about 250 to 400 ° C. The reaction pressure can be about 10 to 60 MPa.

  Reaction conditions such as reaction temperature and reaction pressure are not limited to the above ranges, and can be appropriately determined according to the type of catalyst used.

  The crude methanol thus obtained usually contains, in addition to methanol, unreacted raw materials such as carbon monoxide and hydrogen, carbon dioxide, water, and dimethyl ether. In the present invention, the crude methanol is used as it is as a raw material gas in the next liquefied petroleum gas production process without being purified.

[Dimethyl ether production process]
In the dimethyl ether production process, dimethyl ether (crude dimethyl ether) is produced from the synthesis gas obtained in the synthesis gas production process by reacting carbon monoxide with hydrogen in the presence of a dimethyl ether synthesis catalyst. The crude dimethyl ether produced here contains unreacted raw material carbon monoxide and by-product carbon dioxide.

  The gas fed into the reactor in the dimethyl ether production process may be a gas obtained by separating predetermined components from the synthesis gas obtained in the synthesis gas production process. In general, the synthesis gas is separated into water by gas-liquid separation after cooling, and carbon dioxide is separated by gas-liquid separation after cooling, absorption separation with amine or the like, and then fed into the reactor. The water and carbon dioxide separated here can be recycled to the synthesis gas production process.

  In this dimethyl ether production process, dimethyl ether can be produced according to a known method, for example, by the following method.

  The synthesis reaction of dimethyl ether can be carried out in various types of reactors such as a fixed bed type, a fluidized bed type and a slurry bed type, but it is usually preferred to carry out in a slurry bed type. In the case of the slurry bed type, the temperature in the reactor becomes more uniform, and the amount of by-products produced becomes smaller.

  Examples of the dimethyl ether synthesis catalyst include a catalyst containing one or more methanol synthesis catalyst components and one or more methanol dehydration catalyst components, one or more methanol synthesis catalyst components, and one or more methanol dehydration catalyst components. Examples include a catalyst containing one or more water gas shift catalyst components.

Here, the methanol synthesis catalyst component refers to a component that exhibits a catalytic action in the reaction of CO + 2H ₂ → CH ₃ OH. In addition, the methanol dehydration catalyst component refers to a component that exhibits a catalytic action in the reaction of 2CH ₃ OH → CH ₃ OCH ₃ + H ₂ O. The water gas shift catalyst component refers to a component that exhibits a catalytic action in the reaction of CO + H ₂ O → H ₂ + CO ₂ .

  As the methanol synthesis catalyst component, known methanol synthesis catalysts, specifically, copper oxide-zinc oxide, zinc oxide-chromium oxide, copper oxide-zinc oxide-chromium oxide, copper oxide-zinc oxide-alumina, zinc oxide- Examples thereof include chromium oxide-alumina. In the case of copper oxide-zinc oxide or copper oxide-zinc oxide-alumina, the content ratio of zinc oxide to copper oxide (zinc oxide / copper oxide; mass basis) is about 0.05 to 20, and about 0.1 to 5 In addition, the content ratio of alumina to copper oxide (alumina / copper oxide; mass basis) is about 0 to 2, and more preferably about 0 to 1. In the case of zinc oxide-chromium oxide or zinc oxide-chromium oxide-alumina, the content ratio of chromium oxide to zinc oxide (chromium oxide / zinc oxide; mass basis) is about 0.1 to 10, about 0.5 to 5 Moreover, the content ratio of alumina to zinc oxide (alumina / zinc oxide; mass basis) is about 0 to 2, and more preferably about 0 to 1.

The methanol synthesis catalyst component usually exhibits a catalytic action in a reaction of CO + H ₂ O → H ₂ + CO ₂ and can also serve as a water gas shift catalyst component.

  Examples of the methanol dehydration catalyst component include γ-alumina, silica, silica / alumina, and zeolite, which are acid-base catalysts. Examples of the metal oxide component of zeolite include alkali metal oxides such as sodium and potassium, and alkaline earth metal oxides such as calcium and magnesium.

  Examples of the water gas shift catalyst component include copper oxide-zinc oxide and iron oxide-chromium oxide. In the case of copper oxide-zinc oxide, the content ratio of copper oxide to zinc oxide (copper oxide / zinc oxide; based on mass) is about 0.1 to 20, and more preferably about 0.5 to 10. In the case of iron oxide-chromium oxide, the content ratio of chromium oxide to iron oxide (chromium oxide / iron oxide; mass basis) is about 0.1 to 20, more preferably about 0.5 to 10. Examples of the water gas shift catalyst component that also serves as the methanol dehydration catalyst component include copper (including copper oxide) -alumina.

  The content ratio of the methanol synthesis catalyst component, the methanol dehydration catalyst component, and the water gas shift catalyst component is not particularly limited, and can be appropriately determined according to the type of each catalyst component, reaction conditions, and the like. Usually, the content ratio of the methanol dehydration catalyst component to the methanol synthesis catalyst component (methanol dehydration catalyst component / methanol synthesis catalyst component; mass basis) is about 0.1 to 5, and more preferably about 0.2 to 2. The content ratio of the water gas catalyst component to the methanol synthesis catalyst component (water gas catalyst component / methanol synthesis catalyst component; mass basis) is about 0.2 to 5, more preferably about 0.5 to 3. When the methanol synthesis catalyst component also serves as the water gas shift catalyst component, the total amount of the methanol synthesis catalyst component and the content of the water gas shift catalyst component is the content of the methanol synthesis catalyst component. Is preferred.

  The dimethyl ether synthesis catalyst is preferably a mixture of a methanol synthesis catalyst component, a methanol dehydration catalyst component, and, if necessary, a water gas shift catalyst component. After these catalyst components are uniformly mixed, they may be molded as necessary, or may be pulverized again after molding. Even better catalytic performance may be obtained by uniformly mixing the catalyst components, press-contacting them, and then re-pulverizing the catalyst.

  When using a slurry bed reactor, the average particle size of the methanol synthesis catalyst component, the average particle size of the methanol dehydration catalyst component, and the average particle size of the water gas shift catalyst component are preferably 300 μm or less, more preferably 1 to 200 μm, 10-150 micrometers is especially preferable.

  The dimethyl ether synthesis catalyst may contain other additional components as necessary within the range not impairing the desired effect.

  In the dimethyl ether production process, carbon monoxide and hydrogen are reacted using the above catalyst to produce dimethyl ether.

  As described above, the reaction is preferably performed using a slurry bed reactor.

  When a slurry bed reactor is used, the dimethyl ether synthesis catalyst is used in a state of being dispersed in a medium oil as a solvent and slurryed.

  As a medium oil, it is necessary to be able to stably maintain a liquid state under reaction conditions, for example, aliphatic, aromatic or alicyclic hydrocarbons, alcohols, ethers, esters, ketones, and halides thereof. Etc. One medium oil may be used, or two or more medium oils may be mixed and used. As medium oil, what has a hydrocarbon as a main component is preferable. As the medium oil, light oil from which sulfur content has been removed, vacuum gas oil, hydrotreated coal tar high boiling fraction, Fischer-Tropsch synthetic oil, high boiling food oil, and the like can also be used.

  The amount of the dimethyl ether synthesis catalyst used can be appropriately determined according to the type of solvent (medium oil) to be used, reaction conditions, and the like, but is usually preferably about 1 to 50% by weight based on the solvent. The amount of the dimethyl ether synthesis catalyst used is more preferably 5% by weight or more and particularly preferably 10% by weight or more based on the solvent. The amount of dimethyl ether synthesis catalyst used is more preferably 40% by weight or less based on the solvent.

The gas fed into the reactor is preferably a synthesis gas containing carbon monoxide and hydrogen at CO: H ₂ = 1: 0.5 to 1: 1.5 (molar ratio). The content ratio of hydrogen to carbon monoxide (H ₂ / CO; on a molar basis) in the gas fed to the reactor is more preferably 0.8 or more, and particularly preferably 0.9 or more. Further, the content ratio of hydrogen to carbon monoxide (H ₂ / CO; on a molar basis) in the gas fed to the reactor is more preferably 1.2 or less, and particularly preferably 1.1 or less.

  The gas fed into the reactor may contain components other than carbon monoxide and hydrogen.

  When a slurry bed reactor is used, the reaction temperature is preferably 150 to 400 ° C, more preferably 200 ° C or more, and more preferably 350 ° C or less. By setting the reaction temperature within the above range, the conversion rate of carbon monoxide becomes higher.

  The reaction pressure is preferably 1 to 30 MPa, more preferably 2 MPa or more, and more preferably 8 MPa or less. By setting the reaction pressure to 1 MPa or more, the conversion rate of carbon monoxide becomes higher. On the other hand, the reaction pressure is preferably 30 MPa or less from the viewpoint of economy.

  The space velocity (feeding rate of the raw material gas per kg of catalyst) is preferably 100 to 50000 L / kg · h, more preferably 500 L / kg · h or more, and more preferably 30000 L / kg · h or less. By setting the space velocity to 50000 L / kg · h or less, the conversion rate of carbon monoxide becomes higher. On the other hand, the space velocity is preferably 100 L / kg · h or more from the viewpoint of economy.

  The crude dimethyl ether thus obtained usually contains carbon monoxide and hydrogen, carbon dioxide, water, methanol, etc., which are unreacted raw materials, in addition to dimethyl ether. In the present invention, this crude dimethyl ether is used as it is as a raw material gas for the next liquefied petroleum gas production step without purification.

[Liquefied petroleum gas production process]
In the liquefied petroleum gas production process, the main component of hydrocarbons contained in the crude methanol obtained in the above methanol production process is obtained by reacting methanol and hydrogen mainly in the presence of a catalyst for liquefied petroleum gas production. A lower paraffin-containing gas that is propane or butane is produced. Alternatively, the main component of the hydrocarbon contained in the crude dimethyl ether obtained in the above dimethyl ether production process is mainly propane or butane by reacting dimethyl ether and hydrogen mainly in the presence of a catalyst for producing liquefied petroleum gas. A lower paraffin-containing gas is produced. When the crude methanol obtained in the above methanol production process or the crude dimethyl ether obtained in the dimethyl ether production process does not contain an amount of hydrogen necessary for the LPG synthesis reaction, hydrogen may be added thereto. Then, liquid petroleum gas (LPG) is produced by separating moisture and low-boiling components such as hydrogen and high-boiling components from the obtained lower paraffin-containing gas as necessary. In order to obtain liquefied petroleum gas, you may pressurize and / or cool as needed.

  As a catalyst for liquefied petroleum gas production, a catalyst containing an olefin hydrogenation catalyst component and zeolite, for example, an olefin hydrogenation catalyst component supported on zeolite or an olefin hydrogenation catalyst component supported on a support such as silica. The thing which mixed thing and zeolite etc. are mentioned. Further, a catalyst containing one or more types of methanol synthesis catalyst and one or more types of zeolite, specifically, a Cu—Zn based methanol synthesis catalyst and a USY type zeolite, a Cu—Zn based methanol synthesis catalyst: USY type. Zeolite = 1: 5 to 2: 1 (mass ratio) containing catalyst, Cu—Zn-based methanol synthesis catalyst and β-zeolite, Cu—Zn-based methanol synthesis catalyst: β-zeolite = 1: 5 to 2: Catalyst containing 1 (mass ratio), catalyst containing Pd-based methanol synthesis catalyst and β-zeolite in Pd-based methanol synthesis catalyst: β-zeolite = 1: 5-2.5: 1 (mass ratio), etc. Is mentioned.

Here, an olefin hydrogenation catalyst component refers to what shows a catalytic action in the hydrogenation reaction of an olefin to paraffin. Specific examples include Fe, Co, Ni, Cu, Zn, Ru, Rh, Pd, Ir, and Pt. Further, the methanol synthesis catalyst, refers to a compound which can act as a catalyst in the reaction of _{CO + 2H 2 → CH 3 OH} . In the above-described catalyst containing a methanol synthesis catalyst and zeolite, the methanol synthesis catalyst has a function as an olefin hydrogenation catalyst component. Zeolite exhibits a catalytic action in the condensation reaction of methanol to hydrocarbons and / or the condensation reaction of dimethyl ether to hydrocarbons.

  In this liquefied petroleum gas production process, it is considered that paraffin (LPG) whose main component is propane or butane is synthesized from at least one of methanol and dimethyl ether and hydrogen according to the following formula (3).

In the present invention, carbene (H ₂ C :) is generated by dehydration of methanol by the concerted action of the acid sites and base sites that conform to the space field in the pores of the zeolite. The carbene polymerization produces an olefin whose main component is propylene or butene. More specifically, ethylene is produced as a dimer, but as a trimer, or by reaction with ethylene, propylene is produced as a tetramer, by reaction with propylene, or by dimerization of ethylene. It is thought that.

  In the process of producing olefins, reactions such as production of dimethyl ether by dehydration dimerization of methanol and production of methanol by hydration of dimethyl ether are also considered to occur.

  And the produced | generated olefin is hydrogenated by the effect | action of an olefin hydrogenation catalyst component, and the paraffin, ie, LPG, whose main component is propane or butane is synthesize | combined.

  In the above catalyst, any known Cu—Zn-based methanol synthesis catalyst can be used. Examples of the Pd-based methanol synthesis catalyst include those in which 0.1 to 10% by weight of Pd is supported on a support such as silica, 0.1 to 10% by weight of Pd on a support such as silica, and alkali metals such as Ca. And at least one selected from the group consisting of alkaline earth metals and lanthanoid metals is supported by 5% by weight or less (excluding 0% by weight).

  As the liquefied petroleum gas production catalyst, those in which an olefin hydrogenation catalyst component is supported on zeolite, and those in which an olefin hydrogenation catalyst component is supported on a carrier such as silica and zeolite are mixed are preferable.

  Specific examples of the olefin hydrogenation catalyst component include Fe, Co, Ni, Cu, Zn, Ru, Rh, Pd, Ir, and Pt. The olefin hydrogenation catalyst component may be one kind or two or more kinds.

  Among these, as the olefin hydrogenation catalyst component, Pd and Pt are preferable, and Pd is more preferable. By using Pd and / or Pt as the olefin hydrogenation catalyst component, carbon monoxide and carbon dioxide by-products can be more sufficiently suppressed while maintaining a high yield of propane and butane.

  Note that Pd and Pt may not be included in the form of a metal, and may be included in the form of an oxide, nitrate, chloride, or the like. In this case, it is preferable to convert Pd and Pt to metallic palladium and metallic platinum by, for example, hydrogen reduction treatment before the reaction from the viewpoint that higher catalytic activity can be obtained.

  The treatment conditions for the reduction treatment for activating Pd and Pt can be appropriately determined according to the kind of the supported palladium compound and / or platinum compound.

  As what supported the olefin hydrogenation catalyst component on the zeolite, what supported Pd and / or Pt on ZSM-5 or USY type zeolite is preferable, and what supported Pd on ZSM-5 or USY type zeolite is still more preferable. . By using ZSM-5 or USY type zeolite as the zeolite supporting Pd and / or Pt, higher catalytic activity, higher propane and butane yields are obtained, and carbon monoxide and carbon dioxide by-products are obtained. Can be more sufficiently suppressed.

  From the viewpoint of catalytic activity, Pd and Pt are preferably supported in a highly dispersed manner on ZSM-5 or USY-type zeolite.

  From the viewpoint of selectivity, the supported amount of Pd and / or Pt in this liquefied petroleum gas production catalyst is preferably 0.005% by weight or more, more preferably 0.01% by weight or more, and 0.05% by weight. % Or more is particularly preferable. Further, the supported amount of Pd and / or Pt of the liquefied petroleum gas production catalyst is preferably 5% by weight or less in total, more preferably 1% by weight or less, from the viewpoint of catalyst activity, dispersibility and economy. .7% by weight or less is particularly preferable. By setting the supported amount of Pd and / or Pt in the liquefied petroleum gas production catalyst within the above range, propane and / or butane can be produced with higher conversion, higher selectivity, and higher yield.

  As ZSM-5, high silica ZSM-5 is preferable, and specifically, ZSM-5 having a Si / Al ratio (atomic ratio) of 20 to 100 is preferable. By using ZSM-5 having an Si / Al ratio (atomic ratio) of 20 to 100, higher catalytic activity, higher yields of propane and butane can be obtained, and carbon monoxide and carbon dioxide by-products can be produced. It can suppress more fully. The Si / Al ratio (atomic ratio) of ZSM-5 is more preferably 70 or less, and particularly preferably 60 or less.

Further, the SiO ₂ / Al ₂ O ₃ ratio of the USY-type zeolite is preferably 5 or more, and more preferably 15 or more. The SiO ₂ / Al ₂ O ₃ ratio of the USY zeolite is preferably 70 or less, more preferably 50 or less, more preferably 40 or less, and particularly preferably 25 or less.

  The above liquefied petroleum gas production catalyst may be one in which components other than Pd and Pt are supported on ZSM-5 or USY zeolite within a range that does not impair the desired effect.

  A liquefied petroleum gas production catalyst in which an olefin hydrogenation catalyst component is supported on zeolite can be prepared by a known method such as an ion exchange method or an impregnation method. The catalyst for liquefied petroleum gas production prepared by the ion exchange method may have higher catalytic activity than the catalyst for liquefied petroleum gas production prepared by the impregnation method, and the LPG synthesis reaction may be performed at a lower reaction temperature. Higher hydrocarbon selectivity, and even higher propane and butane selectivity may be obtained.

  The zeolite carrying the olefin hydrogenation catalyst component is used after being pulverized and molded as necessary. Although it does not specifically limit as a shaping | molding method of a catalyst, A dry method is preferable, for example, an extrusion molding method, a tableting molding method, etc. are mentioned.

  As a mixture of the olefin hydrogenation catalyst component supported on the support and the zeolite, a mixture of the Pd catalyst component formed by supporting Pd on the support and the USY zeolite is preferable. By using USY-type zeolite as the zeolite, higher catalytic activity, higher propane and butane yields can be obtained, and carbon monoxide and carbon dioxide by-products can be more sufficiently suppressed.

  The content ratio of the Pd-based catalyst component to the USY-type zeolite (Pd-based catalyst component / USY-type zeolite; mass basis) is preferably 0.1 or more, and more preferably 0.3 or more. By setting the content ratio of the Pd-based catalyst component to the USY-type zeolite (Pd-based catalyst component / USY-type zeolite; mass basis) to be 0.1 or more, a higher LPG yield can be obtained.

  The content ratio of the Pd-based catalyst component to the USY-type zeolite (Pd-based catalyst component / USY-type zeolite; mass basis) is preferably 1.5 or less, more preferably 1.2 or less, and 0 More preferably, it is 8 or less. By making the content ratio of the Pd-based catalyst component to the USY-type zeolite (Pd-based catalyst component / USY-type zeolite; mass basis) 1.5 or less, a higher LPG yield can be obtained, and carbon monoxide and carbon dioxide, Byproduct of methane can be more sufficiently suppressed. Furthermore, by setting the content ratio of the Pd-based catalyst component to the USY-type zeolite (Pd-based catalyst component / USY-type zeolite; mass basis) to 0.8 or less, the LPG yield becomes higher, and heavy hydrocarbons ( C5 or more) can be more sufficiently suppressed.

  Note that the content ratio of the Pd-based catalyst component to the USY-type zeolite is not limited to the above range, and can be appropriately determined according to the amount of Pd in the Pd-based catalyst component.

  The Pd-based catalyst component is one in which palladium is supported on a carrier. From the viewpoint of catalytic activity, Pd is preferably supported in a highly dispersed manner on the support.

  The amount of Pd supported by the Pd-based catalyst component is preferably 0.1% by weight or more, and more preferably 0.3% by weight or more. Further, the amount of Pd supported by the Pd-based catalyst component is preferably 5% by weight or less, more preferably 3% by weight or less from the viewpoint of dispersibility and economy. Propane and / or butane can be produced with higher conversion, higher selectivity, and higher yield by adjusting the amount of Pd supported by the Pd catalyst component within the above range.

  The carrier for supporting Pd is not particularly limited, and any known carrier can be used. Examples of the support include silica (silicon dioxide), alumina, silica / alumina, carbon (activated carbon), and oxides such as zirconium, titanium, cerium, lanthanum, and iron, and two kinds of these metals. Also included are composite oxides containing the above, or composite oxides containing one or more of these metals and one or more other metals.

  Among them, silica is preferable as the carrier for supporting Pd. By using silica as a carrier, propane and / or butane can be synthesized with high selectivity and high yield without carbon dioxide by-product.

The silica as the support preferably has a specific surface area of 450 m ² / g or more, and more preferably has a specific surface area of 500 m ² / g or more. By using silica having a specific surface area within the above range, higher catalytic activity can be obtained, and propane and / or butane can be produced with higher conversion and higher yield.

On the other hand, the upper limit of the specific surface area of silica as a carrier is not particularly limited, but is usually about 1000 m ² / g.

The specific surface area of silica is measured by a BET method using N ₂ as an adsorbed gas using a fully automatic specific surface area pore distribution measuring device such as ASAP2010 manufactured by Shimadzu Corporation.

  The Pd-based catalyst component may be one in which a component other than Pd is supported on the support within a range that does not impair the desired effect.

  The Pd-based catalyst component in which Pd is supported on a carrier (such as silica) can be prepared by a known method such as an impregnation method or a precipitation method.

  For example, Pd-based catalyst components such as those containing Pd in the form of oxides, those containing Pd in the form of nitrates, and those containing Pd in the form of chlorides, Some products need to be activated by reduction treatment. In the present invention, it is not always necessary to activate the Pd-based catalyst component by reducing it in advance, and the Pd-based catalyst component and USY-type zeolite are mixed and molded to produce the liquefied petroleum gas production catalyst of the present invention. Thereafter, the Pd-based catalyst component can be activated by performing a reduction treatment prior to starting the reaction. The treatment conditions for the reduction treatment can be appropriately determined according to the type of Pd-based catalyst component.

  USY-type zeolites include USY-type zeolites containing metals such as alkali metals, alkaline earth metals, transition metals, USY-type zeolites ion-exchanged with these metals, or USY-type zeolites carrying these metals. The proton type is preferable. By using a proton-type USY-type zeolite having an appropriate acid strength and acid amount (acid concentration), the catalytic activity is further increased, and propane and / or butane can be synthesized with high conversion and high selectivity. . Moreover, what carried Pd and / or Pt on the USY type zeolite is also preferable.

The ratio of SiO ₂ / Al ₂ O _{3 of} USY-type zeolite is preferably 5 or more, and more preferably 15 or more. By using a USY-type zeolite having a SiO ₂ / Al ₂ O ₃ ratio of 5 or more, more preferably 15 or more, by-production of carbon monoxide and carbon dioxide can be more sufficiently suppressed, and higher propane And butane selectivity is obtained.

Further, the SiO ₂ / Al ₂ O ₃ ratio of the USY-type zeolite is preferably 70 or less, more preferably 50 or less, more preferably 40 or less, and particularly preferably 25 or less. By using a USY-type zeolite having a SiO ₂ / Al ₂ O ₃ ratio of 70 or less, more preferably 25 or less, a higher conversion ratio of methanol and / or dimethyl ether can be obtained, and methane by-product can be more fully produced. Can be suppressed, resulting in higher propane and butane selectivity.

  The liquefied petroleum gas production catalyst, which is a mixed catalyst of Pd-based catalyst component and USY-type zeolite, is prepared separately after the Pd-based catalyst component and USY-type zeolite are prepared and mixed uniformly. Manufactured. The method for mixing and molding the two catalyst components is not particularly limited, but a dry method is preferred. When both catalyst components are mixed and molded in a wet manner, the movement of the compound between the two catalyst components, for example, the movement and neutralization of the basic component in the Pd-based catalyst component to the acid point in the USY-type zeolite occurs. As a result, the physical properties optimized for the respective functions of both catalyst components may change. Examples of the catalyst molding method include an extrusion molding method and a tableting molding method.

  The liquefied petroleum gas production catalyst may contain other additive components as necessary within the range not impairing the desired effect. For example, the catalyst can be diluted with quartz sand or the like.

  When the reaction is performed in a fixed bed, the composition of the catalyst layer containing the liquefied petroleum gas production catalyst can be changed with respect to the flow direction of the raw material gas. For example, the catalyst layer contains a large amount of zeolite in the former stage and a structure in which the olefin hydrogenation catalyst component is supported on a carrier such as silica or a methanol synthesis catalyst component in the latter stage with respect to the flow direction of the source gas. Can be.

  In the liquefied petroleum gas production process, at least one of methanol and dimethyl ether is reacted with hydrogen using one or more catalysts for liquefied petroleum gas production as described above, and paraffins whose main component is propane or butane, preferably main Paraffins whose components are propane are produced.

  The reaction can be carried out in a fixed bed, a fluidized bed or a moving bed. Reaction conditions such as the raw material gas composition, reaction temperature, reaction pressure, and contact time with the catalyst can be appropriately determined according to the type of catalyst used. For example, the LPG synthesis reaction is performed under the following conditions. Can do.

  As described above, the gas fed into the reactor is the crude methanol obtained in the methanol production process or the crude dimethyl ether obtained in the dimethyl ether production process. The gas fed into the reactor may contain both methanol and dimethyl ether. In that case, the content ratio of methanol and dimethyl ether is not particularly limited, and any of them can be used. Further, hydrogen may be added to crude methanol or crude dimethyl ether as necessary.

  The reaction temperature is preferably 300 ° C. or higher, more preferably 320 ° C. or higher, from the viewpoint of obtaining higher catalytic activity. Further, the reaction temperature is preferably 470 ° C. or less, more preferably 450 ° C. or less, from the viewpoint of higher hydrocarbon selectivity, and further higher propane and butane selectivity and catalyst life. 400 ° C. or less is particularly preferable.

  The reaction pressure is preferably 0.1 MPa or more, more preferably 0.15 MPa or more, from the viewpoint of higher activity and the operability of the apparatus. Further, the reaction pressure is preferably 3 MPa or less, more preferably 2.5 MPa or less, from the viewpoints of economy and safety.

  Furthermore, according to the present invention, LPG can be produced under a lower pressure. Specifically, LPG can be synthesized from hydrogen and at least one of methanol and dimethyl ether under a pressure of less than 1 MPa, or even 0.6 MPa or less.

Gas space velocity of methanol and / or dimethyl ether, from the viewpoint of economy, preferably 1500 hr ^-1 or more, 1800Hr ^-1 or more is more preferable. Further, the gas space velocity of methanol and / or dimethyl ether, higher activity can be obtained and, from the point of higher selectivity for propane and butane is obtained, preferably 60000Hr ^-1 or less, more preferably 30000 hr ^-1 or less .

  The gas fed into the reactor can be divided and fed into the reactor, thereby controlling the reaction temperature.

  The reaction can be carried out in a fixed bed, a fluidized bed, a moving bed, etc., but it is preferable to select from both aspects of controlling the reaction temperature and regenerating the catalyst. For example, as a fixed bed, a quench reactor such as an internal multi-stage quench system, a multi-tube reactor, a multi-stage reactor including a plurality of heat exchangers, a multi-stage cooling radial flow system or a double-tube heat exchange Other reactors such as a system, a built-in cooling coil system, and a mixed flow system can be used.

  The liquefied petroleum gas production catalyst can be diluted with silica, alumina, or an inert and stable heat conductor for the purpose of temperature control. In addition, the liquefied petroleum gas production catalyst can be applied to the surface of the heat exchanger for the purpose of temperature control.

  In the reaction product gas (lower paraffin-containing gas) obtained in this way, the main component of the contained hydrocarbon is propane or butane. From the viewpoint of liquefaction characteristics, the higher the total content of propane and butane in the lower paraffin-containing gas, the better. Further, the obtained lower paraffin-containing gas preferably has more propane than butane from the viewpoint of combustibility and vapor pressure characteristics.

  The obtained lower paraffin-containing gas usually contains moisture, a low-boiling component that is a substance having a boiling point or sublimation point lower than that of propane, and a high-boiling component that is a substance having a boiling point higher than that of butane. Examples of the low boiling point component include carbon monoxide, carbon dioxide, hydrogen as an unreacted raw material, ethane as a by-product, and methane. Examples of the high-boiling component include high-boiling paraffins (pentane, hexane, etc.) that are by-products.

  Therefore, moisture, a low boiling point component, a high boiling point component, etc. are isolate | separated from the obtained lower paraffin containing gas as needed, and liquefied petroleum gas (LPG) which has propane or butane as a main component is obtained. If necessary, unreacted raw materials such as methanol and / or dimethyl ether are also separated by a known method.

  Separation of moisture, low-boiling components, and high-boiling components can be performed by known methods.

  Separation of moisture can be performed, for example, by liquid-liquid separation.

  Separation of low-boiling components can be performed, for example, by gas-liquid separation, absorption separation, distillation or the like. More specifically, it can be carried out by gas-liquid separation or absorption separation at pressurized normal temperature, gas-liquid separation or absorption separation after cooling, or a combination thereof. Moreover, it can also carry out by membrane separation or adsorption separation, and can also carry out by the combination of these, gas-liquid separation, absorption separation, and distillation. For the separation of low-boiling components, a gas recovery process commonly used in refineries (“Petroleum Refining Process”, Petroleum Society / Ed., Kodansha Scientific, 1998, p.28-p.32) is applied. be able to.

  As a method for separating the low-boiling components, an absorption process in which liquefied petroleum gas mainly composed of propane or butane is absorbed in an absorbing liquid such as high-boiling paraffin gas having a boiling point higher than butane or gasoline is preferable.

  Separation of high-boiling components can be performed, for example, by gas-liquid separation, absorption separation, distillation, or the like.

  The separation conditions can be appropriately determined according to a known method.

  For consumer use, from the viewpoint of safety at the time of use, for example, the content of low-boiling components in LPG is preferably 5 mol% or less (including 0 mol%) by separation.

  Moreover, in order to obtain liquefied petroleum gas, you may pressurize and / or cool as needed.

  The components separated here can be extracted out of the system, or can be recycled to any one of the above-mentioned steps. For example, the carbon monoxide and hydrogen separated here can be recycled as raw materials for the methanol production process or the dimethyl ether production process. In addition, methanol, dimethyl ether, and hydrogen can be recycled as raw materials for the lower paraffin production process.

  In order to recycle the separated components, it is possible to employ known techniques such as appropriately providing a boosting means in the recycle line.

  The total content of propane and butane in the LPG produced in this manner can be 90% or more, further 95% or more (including 100%) based on the amount of carbon. In addition, the content of propane in the produced LPG can be 50% or more, further 60% or more, further 65% or more (including 100%) on the basis of carbon amount. ADVANTAGE OF THE INVENTION According to this invention, LPG which has a composition suitable for the propane gas currently widely used as a fuel for household use and business can be manufactured.

  As described above, in the present invention, LPG whose main component is propane or butane is produced from a carbon-containing raw material such as natural gas or synthesis gas via at least one of methanol and dimethyl ether.

  Hereinafter, the present invention will be described in more detail with reference to examples. The present invention is not limited to these examples.

[Example 1]
(Manufacture of catalysts for liquefied petroleum gas production)
As the zeolite carrying the olefin hydrogenation catalyst component, a proton-type ZSM-5 (manufactured by Tosoh Corporation) having a Si / Al ratio (atomic ratio) of 20 was mechanically powdered. Then, 0.5% by weight of Pd was supported on ZSM-5 by the ion exchange method as follows.

  First, 0.0825 g of palladium chloride (purity:> 99 wt%) was dissolved in 10 ml of a 12.5 wt% aqueous ammonia solution at 40-50 ° C. Further, 150 ml of ion exchange water was added to this solution to prepare a Pd-containing solution. 10 g of ZSM-5 zeolite was added to the prepared Pd-containing solution, and the mixture was heated and stirred at 60 to 70 ° C. for 6 hours. After ion exchange in this manner, the sample was repeatedly filtered and washed with ion-exchanged water until no chlorine ions were observed in the filtrate.

  Then, after ZSM-5 ion-exchanged with Pd was dried at 120 ° C. for 12 hours, it was further fired in air at 500 ° C. for 2 hours, and this was mechanically crushed, tableted and sized, A granular liquefied petroleum gas production catalyst (Pd-ZSM-5) having a diameter of 1 mm was obtained.

  The prepared catalyst for liquefied petroleum gas production was filled in a reaction tube, and prior to the reaction, the catalyst was reduced in a hydrogen stream at 400 ° C. for 3 hours.

(Manufacturing LPG)
Methanol synthesis was performed using a synthesis gas having a composition of H ₂ : CO: CO ₂ = 66.6: 31.7: 1.7 (molar ratio) to obtain a methanol-containing gas (crude methanol) having the following composition. .

Methanol: 5.49mol%, dimethyl ether: 0.04 mol%, methyl formate: 0.04 mol%, ethanol: 0.02 mol%, _{methane: 0.04mol%, CO: 29.27mol%} , CO 2: 1.83mol% _{, H 2: 62.19mol%, H} 2 O: 1.10mol%.

The obtained crude methanol was circulated through the catalyst layer for producing liquefied petroleum gas at a reaction temperature of 350 ° C., a reaction pressure of 2.1 MPa, and a gas space velocity of methanol of 2000 hr ⁻¹ (W / F = 9.0 g · h / mol). LPG synthesis reaction was performed. When the product was analyzed by gas chromatography, all carbon-containing compounds other than methane, CO, and CO ₂ were converted to hydrocarbons, and 1.2% of CO was converted to hydrocarbons. The carbon number distribution of the obtained hydrocarbon (including methane in crude methanol) was as follows.

C1 (methane): 3.6 [C-mol%],
C2 (ethane): 25.6 [C-mol%],
C3 (propane): 35.3 [C-mol%],
C4 (butane): 16.2 [C-mol%],
C5 (pentane): 9.8 [C-mol%],
C6 (hexane): 7.6 [C-mol%],
C7 (heptane): 1.9 [C-mol%].

  The obtained hydrocarbon had a total content of propane and butane of 51.5% on the basis of carbon, and was able to synthesize hydrocarbons whose main components were propane and butane even from crude crude methanol.

[Example 2]
As the liquefied petroleum gas production catalyst, one prepared in the same manner as in Example 1 (Pd-ZSM-5) was used.

(Manufacturing LPG)
Dimethyl ether synthesis was performed using a synthesis gas having a composition of H ₂ : CO = 50: 50 (molar ratio) to obtain a dimethyl ether-containing gas (crude dimethyl ether) having the following composition.

Dimethylether: 16.41mol%, methanol: 2.53mol%, methyl formate: 0.08 mol%, ethanol: 0.01 mol%, _{methane: 0.08mol%, CO: 33.67mol%} , CO 2: 15.99mol% _{, H 2: 29.46mol%, H} 2 O: 1.77mol%.

The obtained crude dimethyl ether was circulated through the catalyst layer for producing liquefied petroleum gas at a reaction temperature of 350 ° C., a reaction pressure of 2.1 MPa, and a gas space velocity of dimethyl ether of 2000 hr ⁻¹ (W / F = 9.0 g · h / mol). LPG synthesis reaction was performed. When the product was analyzed by gas chromatography, all the carbon-containing compounds other than methane, CO, and CO ₂ were converted into hydrocarbons, and 6.1% of CO was converted into hydrocarbons. The carbon number distribution of the obtained hydrocarbon (including methane in the crude dimethyl ether) was as follows.

C1 (methane): 3.5 [C-mol%],
C2 (ethane): 25.8 [C-mol%],
C3 (propane): 35.7 [C-mol%],
C4 (butane): 17.1 [C-mol%],
C5 (pentane): 8.9 [C-mol%],
C6 (hexane): 6.8 [C-mol%],
C7 (heptane): 2.2 [C-mol%].

  The resulting hydrocarbon had a total content of propane and butane of 52.8% on a carbon basis, and was able to synthesize hydrocarbons whose main components were propane and butane even from unpurified crude dimethyl ether.

  As described above, according to the present invention, a hydrocarbon whose main component is propane or butane, that is, a liquefied petroleum gas (LPG), from a carbon-containing raw material such as natural gas or a synthesis gas via methanol and / or dimethyl ether. ) Can be economically manufactured.

It is a process flow figure which shows the main structures about an example of the LPG manufacturing apparatus suitable for implementing the manufacturing method of LPG of this invention.

Explanation of symbols

11 reformer 11a reforming catalyst (catalyst for synthesis gas production)
12 Reactor for methanol synthesis 12a Methanol synthesis catalyst 13 Reactor for liquefied petroleum gas production 13a Catalyst for liquefied petroleum gas production 21, 22, 23, 24 lines

Claims (15)

(I) a methanol production process for producing crude methanol containing methanol, hydrogen, and at least one of carbon monoxide and carbon dioxide from synthesis gas using a methanol synthesis catalyst;
(Ii) Liquefaction in which crude methanol obtained in the methanol production process is supplied without purification, and liquefied petroleum gas in which the main component of the contained hydrocarbon is propane or butane is produced using a catalyst for liquefied petroleum gas production. A method for producing liquefied petroleum gas, comprising: a petroleum gas production step. (I) a synthesis gas production process for producing synthesis gas from a carbon-containing raw material and at least one selected from the group consisting of H ₂ O, O ₂ and CO ₂ ;
(II) a methanol production process for producing crude methanol containing methanol, hydrogen, and at least one of carbon monoxide and carbon dioxide from synthesis gas using a methanol synthesis catalyst;
(III) Liquefaction in which crude methanol obtained in the methanol production process is supplied without purification, and liquefied petroleum gas in which the main component of the contained hydrocarbon is propane or butane is produced using a catalyst for liquefied petroleum gas production. A method for producing liquefied petroleum gas, comprising: a petroleum gas production step. (I) a dimethyl ether production process for producing crude dimethyl ether containing dimethyl ether, hydrogen, and at least one of carbon monoxide and carbon dioxide from synthesis gas using a dimethyl ether synthesis catalyst;
(Ii) Liquefaction by supplying the crude dimethyl ether obtained in the dimethyl ether production process without purification and using the catalyst for liquefied petroleum gas production to produce liquefied petroleum gas whose main hydrocarbon component is propane or butane. A method for producing liquefied petroleum gas, comprising: a petroleum gas production step. (I) a synthesis gas production process for producing synthesis gas from a carbon-containing raw material and at least one selected from the group consisting of H ₂ O, O ₂ and CO ₂ ;
(II) a dimethyl ether production process for producing crude dimethyl ether containing dimethyl ether, hydrogen, and at least one of carbon monoxide and carbon dioxide from synthesis gas using a dimethyl ether synthesis catalyst;
(III) Liquefaction that supplies crude dimethyl ether obtained in the dimethyl ether production process without purification and uses the catalyst for liquefied petroleum gas production to produce liquefied petroleum gas whose main hydrocarbon component is propane or butane. A method for producing liquefied petroleum gas, comprising: a petroleum gas production step.   The method for producing a liquefied petroleum gas according to claim 3 or 4, wherein the dimethyl ether synthesis catalyst contains a methanol synthesis catalyst component and a methanol dehydration catalyst component.   The method for producing a liquefied petroleum gas according to any one of claims 1 to 4, wherein the liquefied petroleum gas production catalyst contains an olefin hydrogenation catalyst component and zeolite.   The method for producing a liquefied petroleum gas according to claim 6, wherein the olefin hydrogenation catalyst component is at least one selected from the group consisting of Fe, Co, Ni, Cu, Zn, Ru, Rh, Pd, Ir, and Pt.   The method for producing liquefied petroleum gas according to claim 7, wherein the catalyst for producing liquefied petroleum gas comprises Pd and / or Pt supported on ZSM-5 or USY type zeolite. Or Si / Al ratio of the ZSM-5 (atomic ratio) is 20 to 100, or, liquefied petroleum according to claim 8 _SiO 2 / _Al 2 _{O 3} ratio of the USY-type zeolite is from 5 to 70 Gas production method.   The method for producing liquefied petroleum gas according to claim 8, wherein the supported amount of Pd and / or Pt of the liquefied petroleum gas production catalyst is 0.005 to 5 wt% in total.   The method for producing liquefied petroleum gas according to claim 7, wherein the catalyst for producing liquefied petroleum gas is a mixture of a Pd-based catalyst component obtained by supporting Pd on a carrier and USY-type zeolite.   The method for producing a liquefied petroleum gas according to claim 11, wherein a content ratio of the Pd catalyst component to the USY zeolite (Pd catalyst component / USY zeolite; mass basis) is 0.1 to 1.5.   The method for producing a liquefied petroleum gas according to claim 11, wherein the amount of Pd supported by the Pd-based catalyst component is 0.1 to 5% by weight.   The method for producing a liquefied petroleum gas according to claim 11, wherein the carrier of the Pd-based catalyst component is silica. Method for producing a liquefied petroleum gas according to claim 11 _SiO 2 / _Al 2 _{O 3} ratio of the USY-type zeolite is from 5 to 70.

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