JPS60183038A - Methanol reforming catalyst - Google Patents

Abstract

PURPOSE:To obtain a catalyst having high activity at low temp., by supporting nickel by a composition consisting of copper-zinc or copper-chromium type oxide and oxides of titanium and vanadium. CONSTITUTION:A proper amount of water is added to and mixed with powdery or pasty copper oxide and chromium oxide and the resulting mixture is dried to obtain copper-chromium type oxide which is, in turn, subsequently mixed with titanium oxide and vanadium oxide. The obtained composition as a carrier is immersed in an aqueous nickel nitrate solution and subsequently backed. In this case, the ratio of CuO/Cr2O3 is pref. in a range of 80/20-30/70 on a wt. basis and the containing ratio of titanium oxide and vanadium oxide is 10-30% by wt. of CuO in the total amount of TiO2+V2O5.

Description

[Detailed description of the invention] Misfire I! No. 14 relates to a methanol reforming catalyst.

More specifically, in a method of reforming methanol into a gas containing all hydrogen and carbon monoxide, it selectively generates hydrogen and carbon monoxide, and provides a highly active and long-life catalyst at low temperatures. .

Methanol can be produced on a large scale from coal, natural gas, etc. via synthetic gas, and is easy to transport, so in the future it will be used as an energy source to replace petroleum or as a raw material for various chemical industries. There is great interest as a There is a method of decomposing it into carbon oxide gas and using it as a pollution-free fuel for automobiles or as a raw material for producing reducing gas. On the other hand, hydrogen is separated from this cracked gas,
This hydrogen fuel can be used as a fuel for Kameike power generation, or as a hydrogen fuel for the hydrogenation of various heavy organic compounds in the petroleum industry, and -carbon oxide can also be used for the carbonylation process of various organic compounds.

Although the decomposition reaction of methanol can occur thermodynamically at a relatively low temperature, the presence of a catalyst is indispensable for K in order to carry out the reaction economically. Conventionally, catalysts for total decomposition of methanol include platinum metal elements such as platinum, copper, nickel, chromium, etc. on a carrier such as alumina (hereinafter referred to as At203).
Catalysts entirely supported on base metals such as zinc and their oxides, or catalysts consisting of one or more gold M oxides of copper, chromium, and zinc have been proposed;
It has poor low-temperature activity, lacks heat resistance, and has a short lifespan.
Up to now, many of the conventional catalysts mentioned above have remained at their necks, for example, by simply supporting an alumina support with one or more metals from the group consisting of copper, zinc, nickel, and chromium, or their oxides. Although these catalysts react with methanol even at relatively low temperatures, they have low selectivity for reforming into hydrogen or carbon oxides, tend to cause side reactions that produce methane, carbon dioxide, dimethyl ether, etc., and have a short catalyst life. There is a problem.

Catalysts made of a combination of one or more metals selected from the group of copper, chromium, zinc, and nickel, or oxides thereof, are excellent in terms of activity and selectivity, but have the disadvantage of short life.

Among them, catalysts made of copper-chromium oxides reform methanol into hydrogen and carbon monoxide at relatively low temperatures, but as a result of long-term life tests, as shown in curve (a) in Figure 1, the comparison performance deteriorates in a short period of time. As a result of conducting various analyzes and studies to determine the cause of this, it was found that the copper oxide in activated willow is reduced, changes to the state of metallic copper, and is deactivated.

In view of this situation, the present inventors have conducted various studies in order to solve all of the above problems, and have found that active copper oxides such as OuO or cu, o are reduced to gold-coated copper (aU). Copper-chromium oxide or
We focused on making the copper-zinc oxide contain all of the fifth component, and as a result of extensive research, we were able to support nickel on a composition that contained all of the oxides of titanium and vanadium as the third component. It has been found that the catalyst has high activity and selectivity for the methanol reforming reaction, has a long life, and is extremely excellent. That is, the present invention provides copper-zinc or copper-zinc
The present invention relates to a methanol reforming catalyst in which nickel is supported on a composition consisting of a chromium-based oxide and oxides of titanium and vanadium.

In the present invention, in order to prepare a composition consisting of copper-zinc or copper-chromium oxides, commercially available copper, zinc, or chromium oxides or hydroxides may be used as they are, or the above-mentioned An aqueous solution of a metal compound is mixed with an alkali metal compound, a hydroxide or carbonate of an alkaline earth metal element as a precipitant, either as it is or in an aqueous solution, or with aqueous ammonia, and precipitated. It may be prepared by making. Furthermore, they may be converted into oxides by completely firing them.

Specifically, for example, as a method for hazing a copper-chromium oxide, there are the following methods.

(11 Add JIII amount of water to powdered or paste-like copper oxide and chromium oxide, mix well, and then dry.

(2) Nitric acid steel water bath solution VC* Add sodium chromate or a mixed aqueous solution of ammonium dichromate and aqueous ammonia, mix well to form a precipitate, then wash and dry.
Fire.

(3) Add the barium hydroxide bath solution to the nitrate steel and chromium nitrate bath solution, mix well to form a precipitate, and then wash, dry, and fire.

The following method is generally known as a method for preparing copper-zinc oxides. That is, it is obtained by adding a neutralizing agent such as sodium carbonate or aqueous ammonia to a bath solution of nitrate, copper, and zinc nitrate to form a precipitate, followed by washing, drying, and firing.

The above is an example, and the present invention is not limited to t%.

Next, regarding the method of containing all the oxides of titanium and vanadium, titanium oxide having an anatase crystal form can be suitably used as the titanium oxide. Moreover, vanadium oxide is v! It may be mixed with titanium oxide in the form of O5, for example, with the copper-chromium oxide or copper-zinc oxide, or to form a precipitate of these oxides, titanium oxide, vanadium oxide, etc. Methods that can be used include mixing metallurgical ingredients and mixing simultaneously with the formation of precipitate, or mixing an aqueous solution of a vanadium compound with a water bath solution of a copper or chromium compound or zinc compound and co-precipitating with a precipitating agent.

The method of supporting nickel on the composition obtained in this way may be any conventional method. For example, after soaking the composition as a carrier in an aqueous solution of nickel nitrate,
If the catalyst on which nickel oxide (Nip) is completely supported by firing is subjected to a complete hydrogen reduction treatment, a catalyst on which metallic nickel is supported can be obtained.

The composition of the catalyst of the present invention is preferably in the following range.

First, the ratio of OuO10r20g is 80/2 in terms of IT ratio.
A range of 0.030/70 is preferred. Also, OuO/ZΩ
The ratio of 0 is in the range of 70150 to 50/70 in xi ratio,
Preferably it is in the range of 60/40 to 40/60.

Next, the content ratio of titanium oxide and vanadium oxide is
For the proportion of OuO, T10≧+V, the total of Os is 10
~50% (weight ratio), of which the ratio of TIO Ha05 is preferably in the range of 3/1 to 1/2 (weight ratio). In addition, the ratio of 1jlO supported in these compositions is 0.1 to 10
fL'Ji: % range is suitable, especially [L5~5]
A range of i1t% is preferred.

Vanadium oxide is Tl, which is known as an oxygen donor.
It exerts its effect in combination with O2. Therefore, ■
TomiOs alone has little effect.

Also, T10! + If the ratio of V and Os increases, the activity will decrease and by-products such as methane will increase, which is not preferable.

The catalyst obtained as described above can be used at 550°C for the reaction of reforming methanol into a gas containing total hydrogen and carbon monoxide.
It exhibits activity at such a low temperature, and also exhibits catalytic activity with excellent selectivity toward non-electrolysis, with the ratio of hydrogen and carbon monoxide in the reformed gas being 90% or more.

Hereinafter, the present invention will be specifically explained with reference to Examples.

Example 1 Ammonium dichromate 252.1 f (1 mol) total 1 t
Dissolve in water and add 500cc of ammonia water (2818 liquid)
f and titanium oxide (anatase type) powder 6.
5 g of vanadium trichloride and 5,6 f'i of vanadium trichloride were added, and then copper nitrate crystal 48S22 (2 mol) dissolved in 1 lt of water was added dropwise with stirring. The resulting precipitate mixture was washed with water, dried, and calcined at 450°C for 3 hours.
OuO2 0rlO, :TiO, :V2O3, = 4
9: 5 1: 6.5: 3. 5 (weight ratio)
A mixed composition having the following composition was obtained.

The entire composition was pulverized.1. It was formed into a cylindrical tablet of sl+ll, immersed in an aqueous solution of nickel nitrate, and
One batch of supported catalyst was prepared so that the supported concentration was 1% by weight.

"Kogen 1 A conventionally known copper-chromium oxide catalyst gold was prepared as follows.

Dissolve 252.12 (1 mol) of ammonium dichromate in 1 ton of water and make 500 cc of ammonia water (28% aqueous solution).
t-added to this, 485.2 g (2 mol) of copper nitrate crystals 1
t dissolved in water was added dropwise while stirring. The resulting precipitate was completely washed with water, dried, and calcined at 450° C. for S hours, and then compressed into 5101 cylindrical tablets similar to those in Example 1 to prepare a comparative catalyst.

Example 2 5 cc of each of the catalyst 1 obtained in Example 1 and the catalyst prepared in Comparative Example were charged into a 10 mφ reactor (8US 504), and placed in advance in a hydrogen stream (hydrogen concentration = 1%/N balance). , hydrogen reduction treatment was carried out while raising the temperature from 150°C to 250°C. After that, methanol (purity = 99.9% or more) f LH8V 2 h was added at a reaction temperature of 550°C and under atmospheric pressure.
The catalyst was tested for activity and life.

The results are shown in FIG. In the figure, curve (b) shows the performance of the catalyst of the present invention (catalyst 1), and curve (a) shows the performance of the comparative catalyst.

Incidentally, when analyzed, the set tct of cracked gas at a methanol reaction rate of 90% or more was found to be the catalyst of the present invention (catalyst 1).
If all used, on a molar basis H, 65,8 H, CO5
51%, co, 05%, 0H4El 6chi.

Example S Zinc nitrate (hexahydrate) 269f and cupric nitrate (trihydrate) 4
55ft - 2tK of water was dissolved, titanium oxide (anatase type) powder &5F and vanadium trichloride a6f'i were added thereto, and a 1 molar solution of sodium carbonate was added dropwise while stirring. The resulting precipitate mixture was washed with water and dried for 30 minutes.
It was baked at 0°C for 6 hours. This composition was molded in the same manner as in Example 1, and immersed in an aqueous solution of nickel nitrate.
10 All catalysts 2 were prepared so that the supported concentration was 1% by weight.

Performance evaluation of this catalyst Evaluation was carried out in the same manner as in Example 2 except that the total reaction temperature was 1300° C., and the results are shown in FIG. 2. In the figure, the curve (C) shows the performance of the OuO-ZnO-based catalyst, and the curve (d) shows the performance of the catalyst 2 manufactured by v4 in this example.

Example 4 In the same manner as in Example 1, OuO: cr2o3: Ti
01, 2, 2, and 205 were each prepared to have a composition as shown in Table 1, which was then compressed into a 5WII+1 inner column shape, and then immersed in a nickel nitrate aqueous solution to form a Ni
Catalysts 3 to 11 supported so that the concentration of O supported was 1% by weight
was prepared.

These catalysts were subjected to activity evaluation and life test under the same conditions as in Example 2. The results are shown in Table 1. In addition, the composition as a carrier for comparison V/l, TIO,
and v*Osr-free catalyst 12 and TIO, or v
*0sfi-Catalysts 13 and 14 containing each of them alone were prepared, and the same performance evaluation as in Example 2 was performed. The results are also shown in Table 1.

Table 1: Durability time represents the duration until the methanol reaction rate becomes 90% or less. In addition, the catalyst 5,
Regarding No. 7.11, the durability time until the methanol reaction rate became 80% or less was shown.

Example 5 In the same manner as in Example 6, OuO: ZnO: TiCl
2: Each composition was prepared so that the proportions of V and O were as shown in Table 2, and this? After molding in the same manner as in Example 1, catalysts 15 to 21 were prepared in which NIO was supported at a degree of 1% by weight. Performance evaluation of these catalysts 11il
The reaction was carried out under the same conditions as in Example 2, except that the reaction temperature was 500°C (VCL). The results are shown in Table 2.

Table 2 Example 6 Copper nitrate (trihydrate) 101.29 and chromium nitrate (nase hydrate) 175.2 f were dissolved in 1 t of water, and this lc5
5.69 f of vanadium chloride was added, and further 6.5 ff of titanium oxide powder (anatase type) was added, followed by thorough stirring. I (mol/l) of a sodium carbonate water bath solution was added to this water bath solution to completely form a precipitate, and then washed, dried, fired, and then compressed into 5-diameter cylindrical tablets. This was immersed in a total nickel nitrate aqueous solution to prepare a catalyst 22 in which NiO was supported at a concentration of 1M. When this catalyst 22 was subjected to a life test under the same conditions as in Example 2, it showed almost the same performance as curve (1) in FIG. 1.

Example 2 Among the catalysts prepared in Example 1 and Example 3, the composition used as a carrier (C!uo-OrzO3-TiOl
Catalysts 23 to 28 were prepared by varying the loading concentration of NiO using -VxOs)k. Regarding these catalysts,
Performance evaluation was performed in the same manner as in Example 2. The results are shown in Table 3.

As shown in the examples above, the catalyst of the present invention has high activity, high selectivity, and long life at low temperatures for the reaction of reforming methanol into a gas containing total hydrogen and carbon monoxide. In the above examples, methanol alone was described, but there is no problem in carrying out the entire methanol reforming reaction in the coexistence of a gas containing water vapor, air, etc.

[Brief explanation of drawings]

FIG. 1 and FIG. 2 show a comparison of durability times in methanol reaction between the catalyst of the present invention and a conventional catalyst. Sub-agent 1) Meifu agent Ryo Hagiwara - 88S photo 8'')

Claims (1)

[Claims] A methanol reforming catalyst characterized in that nickel is supported on a composition consisting of a copper-zinc or steel-chromium oxide and an oxide of titanium and vanadium.