JPS61286203A - Reforming method for methanol - Google Patents

Abstract

PURPOSE:To produce catalytically gas contg. H2 and CO from methanol or a mixture of methanol with water with high efficiency for a long period by specifying the order of arrangement of the catalyst depending upon the temp. gradient of the heat source. CONSTITUTION:In the production of gas contg. H2 and CO from methanol or methanol-water mixture utilizing a heat source at >=100 deg.C, a methanol decomposing catalyst A is arranged to a high temp. side and a steam reforming catalyst B for methanol is arranged to a low temp. side in accordance with the temp. gradient of the heat source. Exhaust gas of an engine or gas turbine, etc., is introduced from an inlet 1a in order to utilized the sensible heat of the gas and the gas is discharged from an outlet 1b after feeding heat to the catalyst bed A, B at the low temp. side. Further, above-described raw materials are introduced from an inlet 2a and methanol decomposing reaction is proceeded in the first stage in the catalyst bed A. Then, steam is fed to the discharged gas from an intermediate feeding port 4, and the gaseous mixture is fed to the catalyst bed B where steam reforming reaction for methanol is proceeded and reacted gas is discharged from an outlet 2b.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a methanol reforming method.

More specifically, the present invention relates to a method for producing a gas containing hydrogen and carbon monoxide using a catalyst as a raw material for methanol or a mixture of methanol and water.

[Conventional technology]

Currently, crude oil and petroleum products refined from it are used as raw materials for producing liquid fuel, gaseous fuel, and reducing gas used in power generation boilers, internal combustion engines, etc., but due to the recent rise in oil prices, fuel With diversification in mind, methanol synthesized from fossil fuels other than crude oil is attracting attention as a raw material for producing these fuels and reducing gases.

Furthermore, since methanol is decomposed into a gas containing hydrogen and carbon monoxide at a much lower temperature than naphthalene, it has the advantage that waste heat can be used as a heat source for the methanol decomposition reaction and steam reforming reaction.

The methanol decomposition reaction is the following fl), +21 formula.

C! H30H-') Co + 2H1ΔH25℃==
21.7 koal/mol ・(1) CH10B+n
H10→(2+n)H1+(1-n)OO+nC! 01
= (2) where O(n (1) The methanol steam reforming reaction is expressed as the following equation (3).

CH30H+H10→00B+5H2a2IIC=1)
．． 8 koal, /mol ++ (3) The nine gases produced in the above reaction have the advantage that the calorific value of the produced gas increases by the amount equivalent to the endothermic amount (, U) of the reaction, and furthermore, this produced gas has a high octane number and high output. When applied to a designed internal combustion engine, it has the advantage of improving thermal efficiency by lowering the compression ratio, and enables clean combustion without emitting aldehydes when burning methanol, and is non-polluting for use in automobiles and power generation. It can be used as fuel.

Furthermore, hydrogen is completely separated from the nine gases generated from the above reaction (3) K, and this hydrogen is used as a fuel for fuel cell power generation as a hydrogen source for use in petroleum refining, hydrogenation reactions of various organic compounds in the chemical industry, etc. It can also be used as a reaction (1
), +21, carbon monoxide can be separated from the gas produced and used as a carbon monoxide source.

Conventionally, when decomposition or steam reforming reactions are performed using methanol or a mixture of methanol and water using the sensible heat of exhaust gas from engines, gas turbines, etc. as a heat source, patented catalysts have been used. Only the methanol decomposition reaction or, in rare cases, only the methanol steam reforming reaction was performed.

[Problems solved by the invention = 9] However, in the above conventional method, heat transfer occurs as the reaction progresses,
At the same time, the temperature level of the exhaust gas decreases. This temperature drop causes a drop in the catalyst layer temperature, which in turn causes a drastic reduction in the reaction rate, resulting in a problem of extremely poor efficiency.

Specifically, as shown in FIG. 4, in the conventional method, heat is supplied to the catalyst layer 3 while the exhaust gas passes through an inlet 1a and an outlet 1b, and methanol or a mixture of methanol and water is supplied from an inlet 2a. was introduced and reacted while passing through the catalyst ff13t, and a gas containing all hydrogen, carbon monoxide, and carbon dioxide was obtained from the product gas outlet 2b.

However, the temperature of the exhaust gas is not uniform and has a large temperature gradient that is high near the inlet 1a and low near the outlet 1b, so the catalyst layer 3 also has a large temperature gradient, and the high temperature part near the exhaust gas inlet is catalyzed by heat. There is also the problem that the reaction rate is extremely slow in the low temperature area near the exhaust gas outlet, making it difficult to obtain sufficient performance.

The present invention aims to solve the above-mentioned problems and provide an entire methanol reforming method that can be operated with high efficiency over a long period of time.

[Ninth way to solve the problem]

In order to solve the above-mentioned problems, the present inventors conducted intensive experimental studies and found that, depending on the temperature gradient of the exhaust gas (heat source), a methanol decomposition catalyst was installed on the high temperature side, and methanol steam reforming was performed on the low temperature side. By arranging the catalysts in this order, heat can be effectively recovered from the heat source even if only one type of catalyst is used, and the reaction can proceed at a temperature suitable for the catalyst.

That is, the present invention provides a method for producing methanol or a mixture of methanol and water (t-gas) containing hydrogen and carbon monoxide as raw materials using a heat source with a temperature of 100° C. or higher, in which To provide a methanol reforming method, which is characterized in that methanol decomposition catalysts are arranged in the order of methanol decomposition catalysts on the high vertical side and methanol steam reforming catalysts on the low temperature side.

The methanol decomposition catalyst referred to in the present invention refers to reaction (1), (
21. Catalysts that selectively advance the process include catalysts containing all group V elements such as platinum, palladium, and nickel, or catalysts containing chromium oxide. Specific examples include the following catalysts.

■ Alumina '46 caulked alkaline earth metal oxide,
Catalysts in which one or more metals from the group consisting of platinum and palladium are supported on a carrier coated with an alkali metal oxide, a rare earth element oxide, zinc oxide, chromium oxide, etc.
-68140% Japanese Patent Application FIE59-199045, Japanese Patent Application No. 190669.190670/1986) ■ Support coated with titania in advance with alkaline earth metal oxide, alkali metal oxide, rare earth element oxide, zinc oxide, chromium oxide, etc. Alternatively, one or more metals from the group consisting of platinum and palladium are supported on a rutile titania carrier as a psychocatalyst (Japanese Patent Application Laid-Open No. 59-1) 2855, Japanese Patent Application No. 58-229087.
229088.245787) ■ One or more metals from the group consisting of platinum and palladium on a carrier containing an oxide of an alkaline earth metal element or a carrier containing an oxide of an alkaline earth metal element and an oxide of a rare earth element. Fully supported catalyst (Patent application No. 59-53549)
．． 55550) ■ Catalyst with nickel oxide, chromium oxide, and copper oxide supported on alumina (Japanese Patent Publication No. 58-46346, No. 58-58)
No. 45286] ■ Catalyst with nickel and potassium supported on alumina (
JP-A-57-144031) ■ Catalysts supported or mixed with nickel gold oxide based on one or more oxides of the group consisting of copper, zinc, and chromium (JP-A-57-1) 4158, JP-A-57-1) 4159 No.) Methanol steam reforming in the present invention is a catalyst that allows reaction (3) to proceed in an all-selective manner, such as a catalyst containing copper. Specific examples thereof include the following catalysts.

■ Catalyst containing oxidized steel, chromium oxide gold as main component, and further containing oxides such as manganese and barium (Japanese Patent Publication No. 274) ■ Oxidized steel, catalyst containing zinc oxide as main component Catalysts further containing chromium oxide (Japanese Patent Application Laid-Open No. 57-1) No. 4158), catalysts further containing aluminum oxide, manganese oxide, boron oxide, etc. (Japanese Patent Application Laid-open No. 59-15F)
No. 501] ■ Catalyst with oxidized steel supported on a carrier such as alumina or silica (JP-A-58-1) No. A3b, Takezawa Kamotsune, surface,
VoL20. No, 10. P.

555.1982) The above is just an example and does not particularly limit the present invention.

The reaction conditions of the present invention include a pressure of low -50 K9/crrr'ck and a pressure of 200 to
At a temperature of 800°C, H2O/CH3OH (molar ratio of α9 or less), when using a methanol steam reforming catalyst, 0
~50 to 9/- pressure, 100 to 400C temperature, 1 or more cr) H1010H30H (% # ratio) T 6
It is preferable that

The reason why the pressure is set to t-50k&/- or less as described above is that reactions (1) to (3) become less likely to occur as the pressure increases in terms of thermodynamic equilibrium. In addition, the reaction temperature should be 200°C or higher for total methanol decomposition and 100°C or higher for methanol steam reforming when the pressure is 20 kg7 cw'G and H2O/CH3OH (molar ratio) is 0, the reaction temperature is 200°C or lower, 010H301) (mole ratio) 2: 100℃
When the temperature is below, the methanol conversion rate is 50% in thermodynamic equilibrium.
This is because it is lower than .

Particularly preferable reaction conditions are a temperature of 200 to 500°C when using a methanol decomposition catalyst, 1) H, O/C of 01 to α8! H, OH (molar ratio), at a temperature of 150 to 300°C when using a methanol steam reforming catalyst, from 1 to
H2O/CH3OH (molar ratio) of 5.

The present invention provides a method for producing gas containing hydrogen and carbon monoxide as all raw materials of methanol or a mixture of methanol and water using a heat source with a temperature of 100° C. or higher, in which the high temperature side is adjusted according to the temperature gradient of the heat source. The methanol decomposition catalyst is arranged in the order of the methanol steam reforming catalyst on the low temperature side, and the H,010H,O)I ratio (molar ratio) of the raw material supplied to the methanol decomposition catalyst on the high temperature side is 1.
After carrying out reactions (1) and (2) at a temperature of 9 or less, the H2O/CH3OH ratio (molar ratio) is set to 1 or more when this outlet gas is supplied to the methanol steam reforming catalyst on the low temperature side. The insufficient amount of steam is supplied to the outlet gas, and H2
A method of controlling the O/CH3OH ratio (molar ratio), or H of the raw material supplied to the methanol steam reforming catalyst on the low temperature side,
After the reaction is carried out with the I ratio (molar ratio) of
% / 'ratio) Kn, 6E 5 is supplied with the insufficient amount of methanol or mixed gas with steam, H,010)i30H(
By using a method of controlling (molar ratio) t-, heat is recovered from the heat source with high efficiency and the reaction proceeds efficiently.

〔Example〕

Embodiments of the method of the present invention will be described below with reference to the drawings.

Figure 1~N! , 3 shows the schematic structure of the method of carrying out the present invention, in which methanol decomposition catalysts A, O, and D are placed on the high temperature side.
The methanol steam reforming catalyst B is arranged on the low temperature side in an Et- arrangement.

As shown in Fig. 1, exhaust gas is introduced from the inlet 1a, supplies heat to the catalyst MA on the high temperature side and to the catalyst layer B on the low temperature side, and then supplies heat to the catalyst layer B on the low temperature side.
It is discharged from b. The raw material (methanol or a mixture of methanol and water) is introduced from the inlet 2a, and first the catalyst/water mixture is introduced.
A methanol decomposition reaction is allowed to proceed at i1A, steam is fully supplied to this outlet gas from the intermediate supply port 4, this mixed gas is supplied to the catalyst layer B, a methanol steam reforming reaction proceeds, and the mixture is discharged from the outlet 2b.

l! As shown in Figure 2, the exhaust gas enters the inlet 1a as in Figure wE1.
It is introduced from the outlet 1b and discharged from the outlet 1b.

The raw material is introduced from the inlet 2a, and the methanol steam reforming reaction is first progressed at the catalyst IWIB. Methanol is supplied to this outlet gas from the intermediate supply port 5, and this mixed gas is supplied to the catalyst layer A, where the methanol decomposition reaction is fully progressed. and discharge from outlet 2b.

As shown in FIG. 5, exhaust gas is introduced from the inlet 1a, and a catalyst layer 01 is formed on the high temperature side and a catalyst layer 01 is formed on the medium temperature side.

Heat is supplied to the catalyst layer E on the low temperature side and is discharged from the outlet 1b. The raw material is introduced from the inlet 2a, and is first allowed to undergo a methanol steam reforming reaction in the catalyst layer E, and then the outlet gas contains wc1.
A portion of methanol is supplied from the intermediate supply port 6, and this mixed gas is supplied to the catalyst layer DK to advance the methanol decomposition reaction. A portion of methanol is further supplied to this outlet gas from the second intermediate supply lower, and this mixed gas is supplied to all the catalyst layers 0 to proceed with the methanol decomposition reaction. - For example, Catalyst C is a platinum-supported catalyst, Catalyst D is a catalyst in which nickel oxide vtJ is supported on a carrier containing oxides of copper and chromium, and Catalyst E is a catalyst containing copper oxide, zinc oxide, and alumina. Catalysts can be used.

A specific example is shown below.

In the apparatus of FIG. 1, a 1-inch tube is used, and the catalyst layer A
Platinum catalyst (Pt (L5wt%, MgO5,5wt%,
A40194 wt% composition) t-41, copper, zinc, chromium-based catalyst in catalyst layer B (C!uo 55 wt%, Zn
O50wt%, CR, C315wt%) f2.51 is charged and 500℃ combustion exhaust gas (70 &/h) is injected into the inlet 1a.
It was introduced and tested.

Methanol (460 Yu/h) and steam (α2kP/h
) is supplied from the inlet 2a at 500°C, and a methanol decomposition reaction is carried out in the catalyst layer A, resulting in a 6 Nm"/h
Gas (H, 49.5%, 0019.6 excellent, 00.
A gas composition of 0%, 0H8OH25, 2%, H, O2, 7%) was obtained. Steam (1.4 hours/h) is supplied to this gas from the intermediate supply port 4 at 500°C, and this mixed gas is subjected to a methanol-steam reaction using a catalyst NjIB.
18Nm”/h (D gas (H*64.b, 0012
．． 1%, co, 14.2%, O)1. OH2.6%,
Gas composition of H, O & 2%, OH4CL 5%) is at outlet 2
Obtained from b. The temperature at the exhaust gas outlet 1b was 270°C.

As a result, high-performance gold with a total methanol conversion rate of 91.0% could be obtained.

In the apparatus shown in Fig. 2, a 1-inch tube is used, and the catalyst layer A
Platinum catalyst (Pt15wt%, CaO5,5wt%, A
Composition of Laos 94 wt%) t-4t, catalyst layer B
Copper-zinc catalyst (Ouo 55 wt%, ZnO40
wt%, At, o, 5 wt%) filled with t-21,
Next, a test was conducted by introducing combustion exhaust gas (701 V/h) at 500°C from t-population 1a.

Methanol (α96kliF/h) and steam ([L8
1kf//h) of mixed steam is supplied from the inlet 2a at 250°C, and methanol steam reforming is carried out in the catalyst layer B.
6 (16%, C!O(L 8%, Go! 19
．． A gas composition of 7%, 52% of 0HBOH, 15% of H3O, 7% (hereinafter all expressed as mo1%) was obtained. This gas is supplied with methanol (52 YU/h) and steam (
1) 8 Y/h) of mixed steam was supplied at 500°C, and this mixed gas was subjected to a methanol decomposition reaction using catalyst #A.9.4
Nm”/h of gas (Hs 6 !A, O%, 002α
0%, 00 Snow 7.9%, 0H30H2.4%, H! 0
6%, 0H4CL 7%] was obtained from outlet 2b. The temperature at the exhaust gas outlet 1b was 270°C.

As a result, a high performance with a total methanol conversion rate of 92.5% could be obtained.

In the apparatus shown in Fig. 3, a 1-inch tube is used, and the catalyst layer is 0.
Platinum catalyst (Pt15wt%, BaO2,5wt%, A
220197wt%) f! :2ts catalyst layer with nickel-copper catalyst (N402 wt%, OuO40wt%, 0
r20355 wt%, Mn1O15wt%) f2t,
Copper and zinc catalyst (Ouo 50 wt%, Z
n040wt%, Al*O35wt%, zro, 5wt
%) 'FF2 is charged and combustion exhaust gas at 500℃ (6sk
g/h) was introduced from the inlet 1a and the test was conducted.

Methanol ((L 96kg/h) and steam ((L
81) V/h) of mixed steam is supplied from the inlet 2a at 250°C, and the methanol steam reforming reaction is carried out in the catalyst layer E.
．． 84 Nm”/h of gas (H, 6 (L6%, 0018
%, co, 19. 7%, OEI, OH&
1%, H, gas composition of 158%) was obtained. This gas is supplied with a mixed vapor of methanol (t61w/h) and steam ([1L09w/h) from the first intermediate supply port 6't-500%.
℃, and the mixed gas was subjected to a methanol decomposition reaction using a catalyst layer to produce 6.2 Nm"/h of gas (H! 6 & 0%,
0015.9%, C031α5%, OH, O)! 2.2
H, H, OQ %, 01) 4CL 4% gas composition) was obtained. This gas is supplied with methanol (t
skl? /h and steam (α09kl?/h) were supplied at t-400°C, and the methanol decomposition reaction was carried out in the entire catalyst layer O at 9.6Nms/h.
H Goose 657%, 002α8%, co.

75%, 0HIOH1,6%, HsO5,9%, 0
H4Q, 5ch) is obtained from exit 2b and 9. Exhaust gas outlet 1
The temperature of b was 265°C.

As a result, a high performance with a total methanol conversion rate of 94.6% could be obtained.

〔Effect of the invention〕

As is clear from the above examples, the method of arranging the heat source of the present invention (in order from the methanol decomposition catalyst on the high temperature side to the methanol steam reforming catalyst on the low temperature side according to the temperature gradient of the sensible heat of the exhaust gas) has a high efficiency from the heat source. This is a method of recovering heat and efficiently distributing gas containing hydrogen and carbon monoxide.

[Brief explanation of drawings]

FIGS. 1 to 3 show embodiment a of the present invention! FIG. 4 is a diagram showing an embodiment of conventional methanol decomposition and methanol steam reforming. Sub-agent 1) Sub-agent Ryo Hagiwara - Sub-agent Atsuo Anzai Figure 1 Figure 2

Claims (8)

[Claims] (1) In a method for producing a gas containing hydrogen and carbon monoxide from methanol or a mixture of methanol and water as a raw material using a heat source with a temperature of 100°C or higher, the high temperature side is determined according to the temperature gradient of the heat source. A methanol reforming method characterized in that the methanol reforming catalyst is arranged in the order of a methanol decomposition catalyst at a lower temperature side and a methanol hydrogen gas reforming catalyst at a lower temperature side. (2) The methanol reforming method according to claim (1), wherein the methanol decomposition catalyst comprises a catalyst containing a group VIII element. (3) The methanol reforming method according to claim (1), wherein the methanol decomposition catalyst is a catalyst containing chromium. (4) The methanol reforming method according to claim (1), wherein the methanol steam reforming catalyst comprises a catalyst containing steel. (5) Reaction conditions using methanol decomposition catalyst are 0 to 5
Pressure of 0kg/cm^2G, temperature of 200~800℃,
The methanol reforming method according to claim (1), wherein the H_2O/CH_3OH ratio (molar ratio) is 0.9 or less. (6) The reaction conditions using the methanol steam reforming catalyst are a pressure of 0 to 50 kg/cm^2G, a temperature of 100 to 400°C, and a H_2O/CH_3OH ratio (molar ratio) of 1 or more ( 1) Methanol reforming method. (7) H of the raw material supplied to the methanol decomposition catalyst on the high temperature side
After the reaction is carried out with the _2O/CH_3OH ratio (molar ratio) below 0.9, when this outlet gas is supplied to the methanol steam reforming catalyst on the low temperature side, 1 or more H_2O/CH
The methanol reforming method according to claim (1), wherein the insufficient amount of steam is supplied to the outlet gas to control the H_2O/CH_3OH ratio (molar ratio) so that the H_2O/CH_3OH ratio (molar ratio) is achieved. (8) After the H_2O/CH_3OH ratio (mole ratio) of the raw material supplied to the methanol steam reforming catalyst on the low temperature side is set to 1 or more and the reaction is carried out, when this outlet gas is supplied to the methanol decomposition catalyst on the high temperature side. H_2O/CH less than 0.9
Supply the insufficient amount of mixed gas with methanol or steam so that the molar ratio is _3OH, H_2O/CH_3
The methanol reforming method according to claim (1), which controls OH (molar ratio).