JPS5935658B2 - Production method of nickel metal catalyst - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel method for producing a nickel metal catalyst, which has both high catalytic activity and long catalytic life (that is, strong resistance to carbon precipitation), especially for hydrocarbon steam reforming reactions. The present invention relates to a method for producing a nickel metal catalyst.

Generally, the nickel-based catalysts used industrially are alumina (A1203) or silica (Sin2).
), nickel is supported on a carrier such as
Products made of alloys such as aluminum are known.

However, nickel-based metal catalysts have the following problems.

(a) Metal catalysts used industrially are generally granular, and it is difficult to process these granular catalysts into arbitrary shapes, which is a constraint on equipment design.

(b) In addition, catalysts using a carrier such as alumina are subject to scattering of powder due to crushing, etc., and depending on the conditions of use, it is necessary to provide a device such as a filter to remove the scattered powder.

(e) When a metal catalyst manufactured by developing a nickel alloy is used in equipment that handles hydrocarbons, carbon is likely to be deposited on the surface of the catalyst, and catalyst deterioration is likely to occur.

By the way, it is possible to manufacture a metal catalyst using a nickel steel plate that can be shaped into an arbitrary shape, but it is not possible to obtain a sufficiently satisfactory result using conventional methods for manufacturing metal catalysts.

For example, process a twisted tape using a nickel steel plate (Ni>99%), degrease the tape, pickle it, and heat it to 1250℃.
The nickel metal catalyst was oxidized in air for 48 hours, and subjected to a remote treatment for about 1 hour in a hydrogen stream at 650°C to produce a nickel metal catalyst.

Using the catalyst thus produced, the reaction temperature was 650°C,
When a steam reforming reaction of methane was carried out under the reaction conditions of a reaction pressure of 1 atm, a cylinder speed of 25001/hr, and a steam/methane ratio of 3, catalyst deterioration due to carbon deposition was observed as shown in Table 1.

Therefore, the present invention has been devised to effectively solve the problems with conventional metal catalysts.

The present invention (1) uses a nickel steel plate that can be shaped into any shape as a catalyst, (2) allows the nickel steel plate to exhibit high catalytic activity, and (3) allows the nickel steel plate to have high catalytic activity when handling hydrocarbons. Provided is a method for producing a nickel metal catalyst aimed at keeping carbon deposition low.

The method for producing the nickel metal catalyst of the present invention is produced according to the following steps.

A solution is prepared by dissolving or suspending a compound containing a metal selected from the group consisting of aluminum, silicon, siliconium, magnesium, titanium, and vanadium in water or an organic solvent.

Next, the nickel steel plate is processed into an arbitrary shape, and the steel plate is subjected to degreasing and pickling treatments, and its surface is cleaned.

A thin film of the compound is formed on the surface of the nickel steel plate by immersing the steel plate thus cleaned in the above solution or by applying the solution onto the steel plate.

After the nickel steel sheet on which the thin film of the compound has been formed is dried, it is oxidized in an oxygen-containing atmosphere for a long time at a high temperature of 1000° C. or higher.

By being oxidized in this manner, an oxide of the aluminum metal or the like is formed on the surface of the steel sheet, and at the same time, the nickel steel sheet that is the base material is also oxidized.

Further, the above oxide is diffused into the layer near the surface of the nickel steel sheet.

Further, a nickel metal catalyst is produced by subjecting the oxidized nickel steel plate to reduction treatment in an air stream of hydrogen or carbon monoxide.

The metal catalyst produced in this manner exhibits high activity in steam reforming reactions and the like, and can minimize deterioration of activity due to carbon precipitation and the like.

Next, specific examples of the method for producing a nickel metal catalyst of the present invention will be described.

Example 1 A twisted tape is processed from a commercially available nickel steel plate (Ni>99%), and this tape is immersed in an ethyl alcohol suspension of aluminum acetate.

Afterwards, the tape was taken out from this suspension and heated at 90°C for about 30 minutes.
After drying for 0 minutes, the amount of AI adhered to the nickel tape was approximately 0.0016% as Al2O3. /crA.

This tape with aluminum added to its surface was then 1
Oxidize in air at 000-1250℃ for 48 hours, and then
A nickel metal catalyst was produced by subjecting it to a remote treatment for about 1 hour in a hydrogen stream at 50°C.

Using the catalyst thus produced, the reaction temperature was 650°C,
When the steam reforming reaction of methane was carried out under the reaction conditions of reaction pressure 1 atm, cylinder velocity 25001/hr, and steam/methane-3, the results were as shown in Table 2. In comparison, the effect of improving catalyst life was obtained.

Example 2 The nickel tape used in Example 1 above was immersed in an ethyl silicate solution, then taken out and burned to form a thin film of silicon oxide on the surface.

The amount of silicon adhesion is approximately 0.00 as SiO□.
16? /crA.

This tape with silicon oxide * (Si02) added to its surface was subjected to redox treatment in the same manner as in Example 1 to produce a nickel metal catalyst.

When the same steam reforming reaction as in the example was carried out using the metal catalyst thus obtained, the effect of improving the catalyst life was obtained as shown in Table 3.

Example 3 A nickel tape having the same size and shape as that used in Example 1 was immersed in an ethyl alcohol solution of siliconium oxychloride, taken out, and dried at 90° C. for about 1 hour.

The Zr coverage on this tape was approximately <0.0057 f/ca as ZrO2.

This tape was subjected to oxidation/reduction treatment in the same manner as in Example 1 to produce a nickel metal catalyst.

When such a catalyst was subjected to the same reforming reaction as in Example 1, an improvement effect on the catalyst life was observed as shown in Table 4.

Example 4 A nickel tape having the same shape and size as in the above example was immersed in an ethyl alcohol solution of magnesium acetate, taken out, and dried at 90° C. for 1 hour.

The amount of Mg adhered to the nickel tape at this time was approximately 0.0038 g/crA as MgO.

This Mg-added tape was subjected to redox treatment under the same conditions as in Example 1 to produce an umbrella lining catalyst.

When this nickel metal catalyst was subjected to a reforming reaction, excellent deterioration improvement effects as shown in Table 5 were obtained.

Example 5 A nickel tape having the same shape and size as in Example 1 was immersed in a titanium tetraisopropoxide solution, then taken out and dried at 90° C. for about 1 hour.

At this time, the amount of Ti attached to the tape was approximately 0.0% as TiO2.
OO46? /ca.

This tape was subjected to redox treatment under the same conditions as in Example 1 to produce a nickel metal catalyst.

When this catalyst was subjected to a steam reforming reaction, the effect of improving the catalyst life as shown in Table 6 was obtained.

Example 6 A nickel tape having the same shape, size, and material as in Example 1 was immersed in an alcoholic solution of vanadium oxychloride, taken out, and dried at 90° C. for about 30 minutes.

The amount of V attached to this tape is 0.0048 as v205
? /1yrt.

This tape was subjected to redox treatment in the same manner as in the above example to produce a nickel metal catalyst.

When this catalyst was subjected to steam reforming, Table-
As shown in Figure 7, the effect of improving catalyst life was obtained.

In summary, the present invention exhibits the following excellent effects.

(1) Most of the nickel catalysts currently used industrially are granular and cannot be processed into any shape, but the catalyst using this method can be processed into any shape because commercially available nickel plates can be used. Can be done.

(2) Therefore, it is possible to design an optimal apparatus for reactions that involve a large amount of heat input and output, such as hydrocarbon steam reforming reactions and methanation.

(3) Catalysts using a carrier such as alumina are subject to scattering of powder due to crushing, etc., but the use of metal plates in the catalyst of this method prevents scattering.

(4) Particulate catalysts are difficult to incorporate into a reaction apparatus, but the catalyst according to this method can be easily handled depending on the processing method.

(5) Conventional nickel metal catalysts have a strong tendency to deposit carbon, and it was considered disadvantageous to use them in reactions involving substances with a strong tendency to deposit carbon, such as hydrocarbons. Catalysts with substances added to their surfaces can suppress carbon deposition and increase the utility value of metal catalysts.

Claims (1)

[Claims] 1 Forming a film of a compound containing a metal selected from the group consisting of aluminum, silicon, siliconium, magnesium, titanium and vanadium on the surface of the nickel plate,
The nickel metal catalyst is oxidized at high temperature and then reduced in a reducing gas stream to produce a nickel metal catalyst used for hydrocarbon steam reforming reactions or hydrocarbon synthesis. Manufacturing method.