JPH02277546A - Catalyst for reforming of methanol - Google Patents

Abstract

PURPOSE:To obtain a catalyst for reforming of methanol having high performance and fit for industrial use by supporting a catalytic material consisting of an iron family metal, the oxide of a rare earth element and a platinum family metal on a sepiolite carrier. CONSTITUTION:A catalytic material consisting of an iron family metal, the oxide of a rare earth element and a platinum family metal is supported on a sepiolite carrier to obtain a catalyst for reforming of methanol. In the presence of this catalyst, methanol is decomposed to selectively produce H2 and CO. The iron family metal is Ni or Co and is supported by 2-25wt.% of the amt. of the catalyst. The oxide of a rare earth element is cerium oxide or lanthanum oxide and is supported by 0.5-15wt.%. The platinum family metal is Pt, Ru or Rh and is supported by 0.01-2wt.%. Since the catalyst has high catalytic activity even at low temp., is relatively easily prepd. and requires no special pretreatment, it has high performance and is well fit for industrial use.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a ternary composition catalyst for methanol reforming. More specifically, in the method of reforming methanol into a gas containing H2 and CO, H2 and Co are selectively generated, side reactions are suppressed as much as possible, and the method has high activity even at low temperatures and has a long life. The present invention relates to a catalyst having the following properties.

2. Description of the Related Art Catalysts in which various catalyst substrates are supported on alumina, silica, or other carriers have been proposed as catalysts for reforming methanol.

For example, Japanese Patent Application Laid-open No. 57-68140 discloses that platinum is applied to a carrier prepared by coating alumina with an oxide of a basic substance.
A methanol reforming catalyst is shown that supports one or more metals from the group consisting of palladium.

JP-A-57-144031 discloses a catalyst for decomposing 2-8 mg of nickel atoms and 2-8 mg of potassium atoms per gram of aluminum.

JP-A-57-174138 discloses a methanol reforming catalyst in which nickel is supported on one or more oxides of the group consisting of copper, zinc, and chromium, or hydroxides thereof.

JP-A-57-174139 discloses a methanol reforming catalyst comprising one or more oxides or hydroxides of the group consisting of copper, zinc, and chromium, and nickel oxides or hydroxides. It is shown.

JP-A-59-199043 discloses a methanol reforming catalyst in which one or more metals from the group consisting of platinum and palladium are supported on a carrier prepared by coating alumina with an alkali metal oxide.

JP-A No. 61-232201 discloses a method for producing hydrogen-containing gas by decomposing methanol using a catalyst containing one or more metals from the group consisting of copper, zinc, and metals or their oxides. , a method is shown in which water is allowed to coexist at a ratio of 1 to 99 moles per 100 moles of methanol.

46th Catalyst Symposium (A) 1980, Lecture number 3R1
6, Ni unit, Ru m-element, Rh unit, Nt-Ru binary, Ni-Rh binary, Ni-La2O
It has been shown that a catalyst supporting a catalyst substrate of 3 binary or Ni-La2O3 binary or ternary system can be used for the selective synthesis of a reducing high-calorific gas by catalytic cracking of methanol. For comparison, the case where an alumina support is used in place of the silica phase is also shown.

Journal of the Japan Petroleum Institute, 5ekiyu Gakkaishi, 3
0. (3).

+59-IH (1987) and Journal of the Japan Petroleum Institute, 5ek
iyuGakkaishi, 31. (2), 11
33-171 (1988), Ni was added to a 5102-Mg0 support as a catalyst for the decomposition of methanol into CO and H2.
A supported catalyst is shown.

In addition, as for the literature regarding Seviolite, for example, “
Chemical technology magazine MOL, March 1981 special issue, pages 1-7.”
``Geological News No. 388, September 1986 issue, 6-1
8 pages," and these documents contain general explanatory articles about sepiolite.

Problems to be solved by the invention Among the above, JP-A-57-68140;
The catalysts described in JP-A-174138 and JP-A-57-174139 have problems such as insufficient low-temperature activity and a short life span due to easy carbon precipitation. (Refer to the upper right column of page 2 of JP-A-61-232201, which will be described later) Among the above, the catalyst described in JP-A-57-68140 or the catalyst described in JP-A-59-199043 is However, there is an industrial disadvantage in that the carrier must be coated with an oxide of a basic substance (alkali metal oxide) in advance.

In the catalyst described in JP-A-61-232201, steam must be charged into the reactor together with raw material methanol in order to prevent carbon precipitation.

There are problems from an industrial standpoint.

The catalyst described in JP-A-57-144031 has a low conversion rate of, for example, 52% at a reaction temperature of 350°C. There are problems such as the need for pretreatment at °C.

The catalyst described in the 46th Catalyst Symposium (A) in 1980 is:
Although the initial activity is high, the problem is that the catalyst life is short. (2 of the aforementioned Japanese Unexamined Patent Publication No. 57-144031)
(See the left column at the bottom of the page) The catalysts described in the two journals of the Japan Society of Petroleum Research by Oka have a problem in that the methanol conversion rate is as low as, for example, 42 to 75%.

As described above, none of the conventionally proposed methanol reforming catalysts meets the requirements of high catalytic activity, suppression of by-products, long life, T-performance, etc., and this has been an obstacle to industrialization.

In view of these circumstances, the present invention was made for the purpose of providing a high-performance methanol reforming catalyst that can withstand industrialization.

Means for Solving the Problems The methanol reforming catalyst of the present invention contains a support made of sepiolite, a solubilized product of an iron group metal (at), a rare earth element (a
2) and a catalyst substrate consisting of a platinum group metal (a3).

The present invention will be explained in detail below.

Rib In the present invention, sepiolite is used as a carrier.

Sepiolite is a mineral that is naturally produced in Spain, the United States, Turkey, and other parts of the world, and its main components are silicon dioxide and magnesium oxide.
It contains aluminum oxide, calcium oxide, iron oxide, manganese oxide, sodium oxide, potassium oxide, titanium oxide, nickel oxide, etc. as appropriate. Since it is a naturally produced raw material, the proportions of the above-mentioned components differ slightly depending on the raw material production area (for example, see Table 1 on page 8 of the aforementioned "Geological News No. 388"), but in the present invention, any composition of Sepiolite may also be used.

The carrier made of sepiolite is usually used in the form of particles, but it can also be formed into granules or pellets with a diameter of about 0.05 to 4 mm.

The catalyst substrate to be supported on the above-mentioned carrier is an iron group metal (a
1), oxides of rare earth elements (a2) and platinum group metals (
A ternary composition catalyst substrate consisting of a3) is used.

Nickel or cobalt is used as the iron group metal (a1).

Examples of the rare earth element oxide (a2) include oxides of cerium, lanthanum, praseodymium, thorium, samarium, and the like.

Examples of the platinum group metal (a3) include platinum, ruthenium, rhodium, palladium, and iridium.

Among the above catalyst substrates, taking into consideration the catalytic effect and economic efficiency, the iron group metal (a1) is nickel or cobalt, and the rare earth element oxide (a2) is cerium oxide or lanthanum oxide, platinum group metal. Platinum, ruthenium or rhodium is important as (a3). Two or more types of components belonging to each group can also be used in combination.

@The supported amounts of iron group metal (a1), rare earth element oxide (a2), and platinum group metal (a3) as carrier substrates are 2 to 2, respectively, relative to the total catalyst (total amount of carrier and catalyst substrate).
25% by weight (preferably 6-10% by weight), 0.5-1
5% by weight (preferably 1-6% by weight), 0.01-2
It is appropriate to set the content to % by weight (preferably 0.1 to 0.6% by weight), and the most preferable results can be obtained within this range. Too little of each component will lead to a lack of catalytic effect; on the other hand, even if each component is supported in excess of what is necessary, the catalytic effect will not improve beyond a certain limit, and the pores of the carrier will become clogged, resulting in a decrease in catalytic performance. There are things to do.

The catalyst for methanol reforming of the present invention contains an oxide of an iron group metal (a1), an oxide of a rare earth element (a
2) and a platinum group metal (a3).

The iron group metal (a1), the rare earth element oxide (a2) and the platinum group metal (a3) are each separately in any order,
Alternatively, two or more of them can be mixed in advance and then supported on the carrier. The carrier may be calcined at a temperature of about 200 to 750°C before supporting the catalyst substrate.

When supporting the catalyst substrate on the carrier, first the platinum group metal (a3) is supported on the carrier, and then the iron group metal (a1) and the rare earth element oxide (a2) are simultaneously supported. A particularly excellent catalyst is obtained. More specifically, the following procedure is preferably adopted.

1. The carrier is impregnated with an aqueous solution of platinum group metal (a3), such as chloride, nitrate, or hydrochloric acid, in an amount sufficient to fill the voids in the carrier, and dried at a temperature of about 60 to 100°C. At this time, a predetermined amount of the platinum group metal (a3) chloride, etc., is contained in the impregnating liquid.

20 Next, the dried material is heated to about 400° C. in the atmosphere to decompose the impregnated chlorides and the like.

3. Subsequently, the mixture is maintained at a temperature of about 300 to 400°C in a hydrogen stream for 1 to 6 hours (preferably 2 to 5 hours) for reduction, and then cooled.

4. The platinum group metal (a3) support thus obtained is impregnated in a mixed solution of, for example, an aqueous solution of a nitrate of an iron group metal (a1) and an aqueous solution of a nitrate of a rare earth element, and Dry as in the case of supporting (a3),
Perform heat treatment and reduction.

In addition, in these treatments, rare earth element oxides (a
Since 2) is stable, it remains in an oxide state without being reduced.

Yom l! For methanol decomposition, the reaction tube is typically filled with the catalyst prepared as described above, and the temperature of the catalyst bed is set at 250-400℃.
Preheated gasified methanol may be introduced into the catalyst layer at LH3V (liquid hourly hourly velocity) of 0.5 to 10 hr while controlling the temperature to about 50°C. This decomposes methanol into H2 and co.

The catalyst of the present invention is useful for applications such as synthesis of non-polluting high calorific value fuel gas for internal combustion engines, synthesis of fuel gas for fuel cells, and synthesis of raw material gas for high purity organic synthesis.

Function: In the reaction of reforming methanol into a gas containing H2 and co using a methanol reforming catalyst, the main reaction is CH30H→2H, +G.

In addition to the reaction, CH4, CO2, H20 production reaction CH70H+ HL” CH4+ H2OCH30H+
CO→CH4+QQ□ Carbon production reaction CH30H+ C+ H2+H,0 2CH30H" C+C02,+ 4・H2,0 dimethyl ether production reaction 2 CH30H-CJOC:J+ Side reactions such as HzO proceed. When H,0 is produced as a by-product , GO+ HlO→
A CO2, + H2° reaction is also induced.

When the catalyst of the present invention is used, not only the methanol reaction rate is high, but only the above main reaction proceeds selectively, and CH4, C
Side reactions such as O, HλO production reactions, carbon production reactions, and dimethyl ether production reactions hardly occur. The catalyst of the present invention also has a long life.

Such effects can only be achieved by the combination of the above-mentioned specific carrier and the above-determined catalyst substrate. Depending on the combination, such excellent effects cannot be obtained.

Example Next, the present invention will be further explained with reference to Examples.

Example 1 1151 Particulate sepiolite carrier which had been heated in advance to about 500°C in air to remove moisture (main components were 5i02: 53% by weight, MgO: 19.5% by weight, AfL203: 3
．． 5% by weight, CaO: 3% by weight, Fe2O3: 3% by weight
; particle size 1 mm) was impregnated with 3.3 g of a 1.03% by weight aqueous chloroplatinic acid solution, and heated at 110°C for 2 hours.
After drying for an hour, it was heated to approximately 400° C. in N2 and subsequently reduced in H2.

The obtained platinum support was impregnated with 4.8 g of a mixed solution containing an 8.06% by weight aqueous cerium nitrate solution and a 25.7% by weight aqueous nickel nitrate solution, and dried, heated, and dried in the same manner as described above. I made a reduction. As a result, a ternary composition catalyst was obtained in which the amount of supported catalyst substrates was 4% by weight of Pt 2 O, 4.0% by weight of CeOz, and 8.0% by weight of Ni, based on the total amount of catalyst.

A fixed bed flow reactor was filled with the catalyst obtained using methanol clay, and methanol was reformed. The conditions and results are shown below. In the generated gas composition, "rDME" means dimethyl ether, and "-" means not detected (the same applies below).

Reaction conditions Mosquito vector JLI (SV eL police officer 1st training doctor-” 2cc
[lhr 370℃, 500hr Atmospheric pressure result Methanol reaction rate 81.7% Produced gas composition (%) 30.9 0.9 0.0 - 0.0 Comparative example 1 Seviolite A catalyst was produced in the same manner as in Example 1, except that a commercially available silica carrier was used instead of the carrier, and methanol was reformed under the following reaction conditions.

The results are shown below, and it was found that the methanol reaction rate was low and that a large amount of unreacted methanol was present in the generated gas. Note that, 50 hours after the start of the reaction, it became difficult to continue the reaction due to the generation of a large amount of carbon.

Reaction conditions 1LaJ LH5V Science and Engineering 2cc 3hr 350°C Atmospheric pressure Result Methanol reaction rate 53.0% Outlet gas composition (Ma of $) Higashimon Nariri 50.8 25.2 0. 9 0.0 0.1 23.
1 Comparative Example 2 To 3.2 g of the same Seviolite carrier as in Example 1, l, 03
It was impregnated with 3.3 g of a chloroplatinic acid aqueous solution at a concentration of % by weight, and dried, thermally decomposed, and weighed in the same manner as in Example 1. As a result, the amount of catalyst substrate supported is PLO,4
A monocomponent catalyst with a weight percentage of .

Methanol was reformed using this catalyst.

The conditions and results are shown below.

Reaction conditions 1 Emperor JLHSV anti-ball J'degree' J
c 6hr 370℃, 500hr Atmospheric pressure result Methanol reaction rate 50.2% Outlet gas composition (Maol
4 Examples 2 to 4 The following catalyst substrates were supported on the same Seviolite carrier as in Example 1 according to Example 1 to prepare catalysts.

Example 2 Example 3 of a ternary composition catalyst with the following composition Example 4 of a ternary composition catalyst with the following composition Using these catalysts, methanol reforming was carried out under the same conditions as in Example 1. I pawned it. The results 2 hours after the start of the reaction are shown below.

Example 2 Methanol reaction rate 93.2 $ Produced gas composition (m at %) E at Hλ00 83.5 31.2 2.5 0.5 2.0 0.3
Example 3 Methanol reaction rate 91.2 $ Produced gas composition (maol %) Shiri E13. e 32.5 1.0 1.8 0.7 0
．． 4 Example 4 Methanol reaction rate 90.5% Produced gas composition (vol%) 83.8 33.4 0.8 1.0 0.7 0.3
Effects of the Invention The uninvented catalyst for methanol reforming has high catalytic activity even at low temperatures, selectively decomposing reactions into H2 and CO, CH, Co, H, O production reactions, carbon production reactions, Side reactions such as dimethyl ether production reactions are effectively suppressed, the catalyst life is a concern, no special pretreatment is required for the carrier, the catalyst is relatively easy to prepare, and no special pretreatment is required. There are advantages such as not having to

As described above, the catalyst of the present invention has high performance enough to withstand industrial use as a catalyst for methanol reforming, and the present invention has great industrial significance.

Patent applicant: Tomo Inui

Claims (1)

[Claims] 1. A support made of sepiolite, an iron group metal (a1),
Oxides of rare earth elements (a2) and platinum group metals (a3)
A methanol reforming catalyst supported on a catalyst substrate consisting of: 2. The methanol reforming catalyst according to claim 1, which is a catalyst for selectively producing H2 and CO by decomposing methanol. 3. The supported amounts of iron group metal (a1), rare earth element oxide (a2) and platinum group metal (a3) as catalyst substrates are
2 to 25% by weight and 0.5 to 15% by weight, respectively, based on the total catalyst
The catalyst for methanol reforming according to claim 1, wherein the content is 0.01 to 2% by weight. 4. Claim 1 or 4, wherein the iron group metal (a1) as a catalyst substrate is nickel or cobalt, the rare earth element oxide (a2) is cerium oxide or lanthanum oxide, and the platinum group metal (a3) is platinum, ruthenium or rhodium. 3. The methanol reforming catalyst described in 3.