JPS58174239A - Three-component catalyst for removing oxygen from gas containing oxygen consisting essentially of gaseous hydrogen and its production - Google Patents

Abstract

PURPOSE:To enable the removal of oxygen from an oxygen-contg. gas efficiently and continuously by low temp. catalytic combustion by using a titled catalyst produced by depositing a ferrous metal as a catalytic substrate, an oxide of a rare earth element and a platinum group metal on a carrier of silica or the like. CONSTITUTION:A ferrous metal as a catalytic substrate, an oxide of a rare earth element and a platinum group metal are deposited on a carrier consisting of silica or alumina. 3-12% Ni or C among the ferrous group metal, 1-6% La oxide or Ce oxide among the oxide of the rare earth element and 0.05-1.0% platinum group metal selected from the group consisting of Rh, platinum, Pd, Ru and Ir are deposited thereon. This catalyst has extremely high efficiency of removing oxyen and a long ife as compared with conventional catalysts for removal of oxygen, more particularly an oxygen absorption type catalyst. The catalyst has excellent heat resistance, and even if the sulfur usually acting as a catalytic poison exists in the gaseous mixture to be treated, the poisoning is prevented because the application temp. is low.

Description

[Detailed description of the invention] The present invention relates to an oxygen removal device.

More specifically, the present invention relates to a catalyst that produces oxygen (Yr) and gas from a mixed gas containing hydrogen as a main component and a small amount of oxygen and optionally PL and other gases, and a method for producing the same.

Water IK is Annexia Synthesis 1 Hydrocracking in petroleum refining, hydrorefining, isomerization deflow, and organic synthesis chemistry.

It is important as a reducing agent in various synthetic reactions in industrial chemistry, and has a wide range of uses such as hydrogenation of oils and fats, fuel cells, l# contacts, and metal refining.

Water 3111 has conventionally been produced by reacting expanded hydrogen with oxygen or steam at high temperatures, but it can also be produced by separating it from coke oven gas generated during coal carbonization. In either case, hydrogen is usually produced as a mixed gas in which oxygen and other gases coexist.
Separation and purification of these different gases is essential, but when the proportion of coexisting oxygen is relatively small compared to hydrogen, the conventional method is to shake the mixed gas with an oxygen absorption catalyst to collect and remove oxygen. It has been taken from

Typical examples of such catalysts are iron-group metal unit or binary composition oxygen-absorbing copper catalysts, which have short catalysts and low activity. However, it cannot be said to be advantageous in terms of cost due to the low energy consumption and the need for processing and regeneration.Therefore, there has been a strong desire to develop an alternative catalyst for efficiently removing oxygen from mixed gas.

The purpose of the present invention is to continuously remove oxygen by low-temperature catalytic combustion, which is completely different in composition, form, and function from conventional O-oxygen absorption type catalysts. A five-element catalyst for removing oxygen from an oxygen-containing gas containing hydrogen gas as a main component and a method for producing the same.

The catalyst of the present invention assists the small amount of oxygen contained in the catalyst to undergo a low-temperature combustion reaction with hydrogen and change into water vapor, and exhibits higher oxygen removal efficiency than conventional oxygen-absorbing catalysts. In addition, it has excellent heat resistance and does not lose its activity even after long-term use, and the application temperature is low even if the gas being processed contains sulfur, which is the same level as that contained in ordinary unrefined gas. Can't be poisoned. Furthermore, since the combustion reaction between hydrogen and oxygen in an oxygen-containing gas whose main component is hydrogen, takes precedence over reactions with other coexisting gases, it is affected by the composition ratio of other mixed gases. It has many excellent properties, such as being able to be used conveniently without needing to use it.

The carrier in the present invention has a particle size of, for example, 2 to 4 m.
/ m granular silica or alumina, with a heavy weight [Used after drying and removing water if necessary.

The catalyst substrate of the catalyst supported on the above carrier is iron group metal Jlla.
For example, nickel and/or nickel, and the substrate metal and an oxide of a rare earth element, such as funtan.

m- of oxides of cerium, pufceum, thorium t or samarium and platinum group metals such as rhodium, platinum,
bafcium, ruthenium txh iridium m- and [M
Of these, funtan oxide and cerium chloride are most preferred for the rare earth oxides, and rhodium and badgerum are the most preferred for the platinum group metals. The amount of iron group metal supported relative to the gold catalyst is 8 to 12, particularly preferably 4 to 12.
The range is 6m. Similarly, the amount of the oxide of the rare earth 111') IC is in the range of 1 to 6%, preferably 1 to 8%, and the amount of the platinum group metal is in the range of 0.06 to 10%, preferably 0.1%. A range of ~08 shadow is appropriate. Even if the metal catalyst component [exceeding the above range] is used together, the catalytic effect will not be improved any further, but rather the catalyst performance will tend to deteriorate due to clogging of the pores of the carrier, which is not preferable.

The catalyst of the present invention is obtained by impregnating a granular support of Vq force or alumina with iron group metals, rare earth elements and platinum group metals, for example, nitric acid, in the form of an aqueous solution by means such as spraying, scattering, dipping, etc.
It can be produced by drying at 6G-100°C, followed by thermal decomposition, hydrogen reduction, and heat treatment.

Note that the hydrogen reduction treatment fM performed when supporting the catalyst on the carrier may be omitted depending on the case. This is because the salt mountain is brought into contact with hydrogen in a reaction tower filled with a catalyst described later.

Further, in producing the catalyst of the present invention, iron group metals,
The above-mentioned silica or fc is supported on a granular alumina support for rare earth element oxides and platinum group metals separately in any order or in combination of two or more of them. If this procedure is carried out in such a manner that the iron group metal and the earth element O oxide are simultaneously supported, a particularly excellent catalyst with excellent acid group removal performance can be obtained.

Specifically, a granular carrier of silica or alumina is impregnated with platinum group metal, for example, nitric acid, in an amount sufficient to fill the voids in the carrier, and dried at 60 to 100°C. The concentration of the platinum group metal nitrate at this time is such that a predetermined amount is contained in the nitrate, and then the dried material is heated to 850° C. to impregnate it and decomposed with nine nitric acid mt. The platinum group metal support, which has been neglected in this way, is impregnated, for example, in a mixed solution of nitrate of iron group metal and a water bath solution of nitrate of rare earth element. Dry and heat treat in the same way as when drying, and add water to ma! in an air stream. >ratoo ~aoo℃ (good 1t, <h20
0'0), heated externally at 0.6 to 1.6 M (approximately 1 hour per 1 hour), and then heated at 100 to 800°C for 10
The oxides of rare earth elements are kept for 60 minutes (20 to 80 minutes depending on the needle) and then cooled after reduction. Oxides of group metals, rare earth elements and platinum group metals lAw-
The ternary composition catalyst consists of hydrogen [mainly acid-containing gas mixture], that is, in addition to hydrogen and oxygen, monoacid (1'X, i
i1*, gases containing methane, ethane, ethylene, leg acid gas, small amounts of aromatic compounds, sulfur compounds, etc., such as coke oven gas, natural gas, steam reformed gas of naphtha heavy oil, water gas, and these gases It is used to remove the small amount of oxygen present from hydrogen gas separated from carbon dioxide, but it is especially used to remove the small amount of oxygen present from hydrogen gas, etc., which is a by-product during carbonization of stone removal, such as coke oven gas. A small amount of oxygen [
Good results are obtained when applied to remove the small amount of oxygen from a mixed gas containing it.

For example, oxygen can be removed from an oxygen-containing mixed gas mainly composed of hydrogen using the catalyst of the present invention as follows. That is, as described above, the catalyst is produced, packed into a reaction tower, and the temperature of the catalyst bed is adjusted to between room temperature and 800°C.
10-49 m 7' per catalyst capacity 11 while controlling
hr of oxygen-containing mixed gas kJ mainly composed of hydrogen is passed through.

The catalyst of the present invention has an extremely high oxygen removal efficiency, a long power and lifespan, and excellent heat resistance, compared to conventional oxygen removal catalysts, especially oxygen absorption acid catalysts, and has excellent heat resistance in the mixed gas being treated. Even if sulfur, which normally acts as a catalyst poison, is present, it will not be poisoned because the overload temperature is low.

Next, the present invention will be further explained by presenting examples, and the present invention is not limited to the following examples unless otherwise specified.W5? , "Part" and "%" in 1
Each company tastes "heavy IT part" and "1 part 1%] k, 1.

Example 1 0.46% in 12.5 parts of commercially available silica (particle size 8-4!11/IEI) heated to about 400°C to remove all moisture
984.9 parts of an aqueous solution of rhodium nitrate with a concentration of 984.9 parts is impregnated, dried at 6°C, and heated to about 850"C in the atmosphere to decompose the nitrate.
The tube was impregnated with 82.4 parts of a mixed solution containing 0.1% nickel nitrate water bath solution and 4.61% concentration nickel nitrate water bath solution 1 & t, dried at 6G-100°C, and then about 860"CK in air: Heat to decompose nitrates. Once cooled, raise the temperature by heating from 1 temperature to 200"G in a water flow for 1 hour, hold at the temperature for 20 minutes to reduce, and then cool to room temperature. , a ternary composition composite catalyst v& was obtained. In Naoto's treatment, funtan is not reduced and remains as an oxide. The composition of the obtained catalyst is as follows.

Nickel 6.54 Funtan oxide 1.6% Rhodium o, iFI* Example 2 The catalyst obtained by the method of Example 1 was used, and a coke oven Ganu TV type reaction with the composition shown in Table 1 was used as a test sample. −
It was allowed to pass through at a rate of 11 pl 1 m/kr of the catalyst packed in the tank. At this time, @g between the gas introduction 3ilWFI to the catalyst layer and the catalyst layer reaction temperature at 100% oxygen removal rate.
AVr It is shown in Fig. 1 as a dot. In addition, for comparison,
25e group EMK (6,74Ni-1,4*La203)
Also, the results using an on-vehicle single catalyst (06% Pd) are also shown.

@1 From the results shown in Table @1, it is clear that the ternary composition yarn of the present invention v
When I& is used, the combined effect of the catalyst components is reduced to fusion. In other words, the catalyst of the present invention maintains high catalytic activity over a long period of time, and no decrease in catalyst VI and activity is observed.In contrast, the commercially available Pd single catalyst used as a comparative example and the Binary! 11 Since the activity of the 11-seed fiber decreases as the overgas time passes, the reaction degree of the catalyst layer must be gradually increased in order to maintain the oxygen removal rate at 100%.

Example 8 Catalyst obtained by the method of Example 1? M, hydrogen gas vv containing 11000 pp of oxygen gas as sample A material
m + 49 m37kr per 11 catalysts packed in reactor
passed at a rate of At this time, the relationship between the concentration of residual oxygen gas in the hydrogen gas at the outlet of the catalyst tower and the reaction temperature of the catalyst layer 1 is shown graphically in Figure 2.As a comparative example, a ternary composition catalyst (6.7%Nl- The results using 1,4*Ly, 03) and a commercially available single catalyst (0,5% Pd) are also shown. As is clear from the results shown in FIG. 2, when the ternary composition catalyst of the present invention is used, the 0.0% at the outlet of the catalyst layer is maintained at a catalyst layer temperature slightly higher than room temperature. The concentration can be set to 11r1 ppm or less, and the oxygen removal efficiency is extremely high. In contrast, as a comparative example, unreacted acid residue remains in the treated hydrogen gas even if the temperature is increased, and the oxygen removal efficiency is lower than that of the present invention. It can be seen that the value is extremely low compared to other products. It can be seen that the product of the present invention is advantageous in that it has a higher oxygen removal efficiency than the commercially available single catalyst, which supports expensive badge rum at a relatively high concentration.

[Brief explanation of the drawing]

FIG. 1 is a graph showing the relationship between the test gas conduction time to the catalyst layer and the catalyst layer reaction temperature in Example 2, and FIG. 2 is a graph showing the relationship between the residual oxygen concentration in the test gas after oxygen removal in Example 8. A graph showing the relationship with catalyst layer reaction temperature is shown. Applicant No. 11 Gadong Inui Tomoyuki

Claims (1)

[Scope of Claims] (1) A hydrogen gaff characterized by supporting a group # metal, an oxide of a rare earth element, and a platinum group metal as catalyst substrates on a carrier made of V-liquid or alumina. Oxygen-containing gas containing ij as the main component) [1A catalyst. (2) Among iron group metals as catalyst substrates, nickel or copal) t8-12g6, and among rare ±1i15e element oxides, lanthanum oxide or cerium oxide 1-651
and 0.0 of a platinum group metal selected from Il consisting of rhodium, platinum, platinum, A/tenium, and iridium.
6 to 1.0% of acid WA from an oxygen-containing gas containing hydrogen gas as a main component according to claim 1
Ternary composition catalyst for remover (3) First step of supporting platinum group gold (mt) on a carrier made of Vlika or alumina, iron group metal as a catalyst substrate, rare earth χ oxide and tp
[Characteristics of a method for producing a three-way composition catalyst O for removing oxygen from an oxygen-containing gas containing hydrogen gas as a main component. (4) The iron group metal as a catalyst substrate is nickel or cobalt, the oxide of the p1 rare earth element is lanthanum oxide or cerium oxide, and the platinum group metal is nickel or cobalt. 9. A method for producing a ternary composition catalyst for removing zero oxygen from an oxygen-containing gas containing hydrogen gas as a main component according to claim 8, wherein the metal is selected from the group consisting of aluminum and iridium.