JPH10151341A - Sulfur compound adsorbent - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a highly durable sulfur compd. adsorbent capable of efficiently adsorbing and removing sulfur compds. from a gas contg. relatively small amts. of such malodorous sulfur compds. as hydrogen sulfide, mercaptanes and sulfides and the balance hydrocarbons or further from a gas such as air contg. the malodorous sulfur compds. SOLUTION: This sulfur compd. adsorbent is formed by depositing at least one kind of element selected from a group consisting of Ti, Zr, Fe, Cu, Ce and La and at least one kind of element selected from a group consisting of Pt, Au and Pd on the manganese oxide having 250m<2> /g specific surface and 37±1 deg. angle (2θ) of diffraction at the diffraction peak as the maximum intensity in X-ray diffraction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION Gas fuels used in ordinary households, such as city gas and propane gas, are usually provided with sulfur compounds in order to make them smell sensible if they leak. Contains odorants. Therefore, when the above-mentioned city gas or the like is used as a hydrocarbon as a raw material for reaction of a fuel cell as a hydrocarbon, or in applications such as a high-pressure filler in a spray container, it is harmful to a required reaction,
May cause discomfort to the user of the spray, and in some cases,
It can even be toxic.

[0002] The present invention can effectively remove the above-mentioned sulfur compound-based odorant before providing a hydrocarbon gas such as city gas or propane gas to the above-mentioned use, and can be used for various purposes. The present invention relates to a sulfur compound adsorbent capable of effectively removing a sulfur compound-based odor generated in a facility or an apparatus, for example, a toilet or a refrigerator.

[0003]

2. Description of the Related Art Conventionally, sulfur compounds having a bad smell are mainly adsorbed and removed by activated carbon. However, if hydrocarbons, which are the main components such as city gas and propane gas, are adsorbed with activated carbon in this way, the hydrocarbon itself occupies the pores of the activated carbon, and the problem is that sulfur compounds are not sufficiently adsorbed on activated carbon. is there. Conventionally, as adsorbents other than activated carbon, manganese dioxide by electrolysis and copper zeolite obtained by ion-exchanging ion exchange sites of zeolite with copper have been known. There is a problem that sulfides (sulfides) such as methyl hardly adsorb.

[0004]

SUMMARY OF THE INVENTION The present invention has been made to solve the conventional problems in the above-mentioned adsorbents for sulfur compounds, and is intended to balance hydrocarbons and to use a relatively small amount of hydrogen sulfide. , Mercaptans, sulfides (sulfides), and other gases containing sulfur compounds having a bad odor, as well as gases containing sulfur compounds having a bad odor as described above, for example, the above-mentioned sulfur compounds efficiently from air. It is an object to provide an adsorbent that can be adsorbed and removed.

[0005]

The sulfur compound adsorbent according to the present invention has a specific surface area of 50 m ² / g or more and the diffraction angle (2θ) of the diffraction peak of the maximum intensity in X-ray diffraction is 37 ° ± 1 °. Ti, Zr, Fe,
It is characterized by supporting at least one element selected from the group consisting of Cu, Ce and La and at least one element selected from the group consisting of Pt, Au and Pd.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, manganese oxide is hereinafter referred to as a carrier, and at least one element selected from the group consisting of Ti, Zr, Fe, Cu, Ce and La is represented by A
At least one element selected from the group consisting of Pt, Au and Pd is sometimes called a group B element, and these group A and group B elements are sometimes called active components. In the present invention, manganese oxide means manganese dioxide, but also includes non-stoichiometric manganese dioxide as already known.

The present inventors have already found that the specific surface area is 50 m ^2.
/ G or more, and a manganese oxide having a diffraction angle (2θ) of a diffraction peak (2θ) of the maximum intensity in X-ray diffraction of 37 ° ± 1 ° effectively adsorbs a sulfur compound (Japanese Patent Application Laid-Open No. Hei 8- No. 173795). The reason why such an adsorbent composed of manganese oxide can effectively adsorb sulfur compounds even in a system using hydrocarbons as a balance gas is not clear yet, but the specific surface area and the X-ray diffraction are not clear. It is considered that oxygen vacancies of manganese oxide having characteristics are significantly involved.

The present inventors have further studied the adsorption of manganese oxide on sulfur compounds. As a result, the above-mentioned manganese oxide was found to contain Ti, Zr, Fe, Cu, Ce and La.
At least one element selected from the group consisting of (Group A elements) and at least one element selected from the group consisting of Pt, Au and Pd (Group B elements) as an active component, thereby producing a hydrocarbon. The present invention has been found that, in a system using a gas as a balance gas, the adsorption performance for various sulfur compounds including sulfides is further improved, and the sustainability of the adsorption performance for various sulfur compounds is further improved. It is a thing.

Manganese oxide having a specific surface area of 50 m ² / g or more as described above and a diffraction angle (2θ) of a diffraction peak of the maximum intensity in X-ray diffraction of 37 ° ± 1 ° is:
For example, a precursor that gives manganese oxide by firing, for example, manganese hydroxide, or manganese carbonate, a manganese salt such as manganese acetate, firing, adjusting firing conditions such as atmosphere, temperature, time, etc. Accordingly, it can be obtained by performing an acid treatment. For example, manganese oxide having the above characteristics can be obtained by calcining manganese carbonate at a temperature in the range of 250 to 450 ° C., and then performing acid treatment using an acid such as nitric acid. In addition, as another method, a water-soluble manganese salt, for example, manganese nitrate, manganese sulfate, manganese acetate, and the like are reacted with potassium permanganate, and then washed with water and dried to obtain manganese oxide having the above characteristics. be able to.

In order to make the manganese oxide carry the group A element and the group B element as active components, for example,
As a first method, when manganese carbonate is calcined to form manganese oxide, a compound of the above element is mixed with manganese carbonate and calcined, or manganese nitrate and potassium permanganate are reacted with um. Thus, manganese oxide supporting the above element may be obtained. In this method, it is particularly preferable to use a salt compound as the compound of the above element. In the case where manganese oxide carrying a group A element and a group B element as active components is prepared by this method, the obtained manganese oxide has a specific surface area of 50 m ² / g or more and a maximum intensity in X-ray diffraction. Has a diffraction angle (2θ) of 37 ° ± 1 °. Of course, group A elements and B
The adsorbent itself as a composite carrying the group elements also has a specific surface area of 50 m ² / g or more, and the diffraction angle (2θ) of the diffraction peak of the maximum intensity in X-ray diffraction is 37 ° ± 1 °.

As long as the method of producing manganese oxide itself is as described above, regardless of whether or not a group A element and a group B element are supported when preparing manganese oxide, the obtained manganese oxide is The specific surface area is 50 m ² / g
As described above, the diffraction angle (2θ) of the maximum intensity diffraction peak in X-ray diffraction is 37 ° ± 1 °.

As a second method, after preparing manganese oxide having the specific surface area characteristics and the X-ray diffraction characteristics, the powder is mixed with an aqueous solution of a salt compound of the element, and then evaporated to dryness. May be. Of course, if necessary,
These first and second methods may be performed in combination.

In the sulfur compound adsorbent according to the present invention,
The loading of the group A element is preferably in the range of 1 to 20% by weight in total. Here, the carrying ratio of the group A element means the ratio (% by weight) of the group A element to the total amount of the active ingredient and manganese oxide. When the loading of the group A element is less than 1% by weight, there is almost no increase in the adsorptive capacity due to the addition of the group A element, while when it exceeds 20% by weight, the adsorptive capacity decreases. .

Further, in the sulfur compound adsorbent according to the present invention, the total loading of the group B element is preferably in the range of 0.01 to 1% by weight. Here, the loading ratio of the group B element refers to the ratio (% by weight) of the group B element to the total amount of the active ingredient and manganese oxide. The supporting rate of the group B element is 0.01
When the amount is less than 1% by weight, there is almost no increase in the adsorbing ability due to the addition of the group B element. On the other hand, when it exceeds 1% by weight, the adsorbing ability decreases.

In the sulfur compound adsorbent according to the present invention, as described above, by adsorbing the group A element and the group B element on the manganese oxide in a complex manner, it is possible to synergistically enhance the adsorbing ability for the sulfur compound. In addition, the durability of the adsorption performance for various sulfur compounds is improved. .

The adsorbent according to the present invention can be formed into various shapes such as a honeycomb shape and a spherical shape by a conventionally known forming method. In this molding, a molding aid, a reinforcing material, an inorganic fiber, an organic binder, and the like may be appropriately compounded. Further, it can be coated and supported on a preformed base material by a wash coat method or the like. Further, it may be based on other conventionally known methods for preparing an adsorbent.

According to the adsorbent according to the present invention, hydrogen sulfide,
Mercaptans such as methyl mercaptan and t-butyl mercaptan, and sulfides (sulfides) such as methyl monosulfide and methyl disulfide can be efficiently adsorbed and removed.

[0018]

EXAMPLES The present invention will be described below with reference to examples.
The present invention is not limited by these examples.

Example 1 A mixed aqueous solution of manganese nitrate / titanyl sulfate was prepared by dissolving 121.8 g of manganese nitrate hexahydrate and 200 g of titanyl sulfate at a concentration of 100 g / L in 100 mL of ion-exchanged water. Separately, 40 g of potassium permanganate was dissolved in 200 mL of ion-exchanged water to prepare an aqueous potassium permanganate solution.

While stirring the above aqueous solution of potassium permanganate, the above mixed aqueous solution of manganese nitrate and titanyl sulfate was added dropwise, and the reaction was completed in about 30 minutes. The obtained reaction product was filtered, washed with ion exchanged water, dried, and
Manganese oxide containing 65 g was obtained. The manganese oxide containing Ti had a specific surface area of 170 m ² / g and a Ti loading of 6.2% by weight.

A dinitrodiammineplatinic nitric acid solution is added to 10 g of the Ti-supported manganese oxide together with an appropriate amount of ion-exchanged water so that the solution becomes 0.05 g in terms of Pt, and a slurry is formed. Loading rate 0.5% by weight,
Manganese oxide having a Ti loading of 6.2% by weight was obtained.

Example 2 A Pd carrying ratio was obtained in the same manner as in Example 1 except that a palladium chloride solution was added in an amount of 0.05 g in terms of Pd in place of the dinitrodiammine platinum nitrate solution. Manganese oxide having a content of 0.5% by weight and a Ti loading of 6.2% by weight was obtained.

Example 3 The procedure of Example 1 was repeated, except that a gold chloride solution was added in an amount of 0.05 g in terms of Au in place of the dinitrodiammineplatinic nitrate solution. 0.5
Manganese oxide having a Ti content of 6.2% by weight was obtained.

Example 4 The procedure of Example 1 was repeated, except that titanyl sulfate was replaced with 100 g /
70 g of manganese oxide containing Zr was obtained in the same manner as in Example 1 except that 158 g of zirconyl sulfate having an L concentration was used. The manganese oxide containing Zr has a specific surface area of 230 m
² / g, and the Zr loading was 6.8% by weight. Thereafter, the same operation as in Example 1 was performed to obtain a Pt carrying ratio of 0.5.
Thus, manganese oxide having a Zr loading of 6.8% by weight was obtained.

Example 5 63 g of manganese oxide containing Fe was obtained in the same manner as in Example 1, except that 59.0 g of ferrous sulfate heptahydrate was used instead of titanyl sulfate. Was. The manganese oxide containing Fe has a specific surface area of 249 m ² / g,
The Fe loading was 6.5% by weight. Thereafter, the same operation as in Example 2 was performed to obtain manganese oxide having a Pd loading of 0.5% by weight and an Fe loading of 6.5% by weight.

Example 6 The procedure of Example 1 was repeated, except that 51.3 g of copper nitrate trihydrate was used instead of titanyl sulfate.
62 g of manganese oxide containing Cu was obtained. This manganese oxide containing Cu has a specific surface area of 208 m ² / g and Fe
The loading was 6.1% by weight. Thereafter, the same operation as in Example 3 was performed to obtain an Au loading of 0.5% by weight and a Cu loading of 6.
1% by weight of manganese oxide was obtained.

Example 7 In the same manner as in Example 1, except that 45.6 g of cerous nitrate pentahydrate was used instead of titanyl sulfate, 78 g of manganese oxide containing Ce was obtained. Was. The manganese oxide containing Ce had a specific surface area of 208 m ² / g and a Ce loading of 3.8% by weight. Thereafter, the same operation as in Example 1 was carried out to obtain a Pt carrying ratio of 0.5% by weight and C
e Manganese oxide having a loading of 3.8% by weight was obtained.

Example 8 60 g of La-containing manganese oxide was obtained in the same manner as in Example 1, except that 45.4 g of lanthanum nitrate hexahydrate was used instead of titanyl sulfate. This La
Has a specific surface area of 203 m ² / g and a La loading rate of 4.2% by weight. Thereafter, the third embodiment
The same operation as described above was carried out to obtain an Au loading of 0.5% by weight and La
Manganese oxide having a loading of 4.2% by weight was obtained.

Example 9 The procedure of Example 1 was repeated except that titanyl sulfate 4 having a concentration of 100 g / L was used.
Except that 0 g was used, 62 g of manganese oxide containing Ti was obtained in the same manner as in Example 1. The manganese oxide containing Ti has a specific surface area of 180 m ² / g and a Ti loading of 1.
It was 1% by weight. Thereafter, the same operation as in Example 3 was performed to obtain an Au loading of 0.5% by weight and a Ti loading of 1.1% by weight.
Of manganese oxide was obtained.

Example 10 The procedure of Example 1 was repeated except that the concentration of titanyl sulfate 6 was 100 g / L.
70 g of manganese oxide containing Ti was obtained in the same manner as in Example 1 except that 00 g was used. The manganese oxide containing Ti had a specific surface area of 185 m ² / g and a Ti loading of 19.0% by weight. Thereafter, the same operation as in Example 3 was performed to obtain an Au loading of 0.5% by weight and a Ti loading of 19.0.
% Manganese oxide was obtained.

Example 11 In Example 3, 0.001 g of the gold chloride solution was converted to Au.
A in the same manner as in Example 3 except that
Manganese oxide having a u loading of 0.01% by weight and a Ti loading of 6.2% by weight was obtained.

Example 12 The procedure of Example 3 was repeated, except that the gold chloride solution was added in an amount of 0.1 g in terms of Au. 6.2% by weight of manganese oxide were obtained.

Example 13 Zr was prepared in the same manner as in Example 4 except that 31.6 g of zirconyl sulfate having a concentration of 100 g / L was used.
66 g of manganese oxide containing The manganese oxide containing Zr had a specific surface area of 233 m ² / g and a Zr loading of 1.3% by weight. Thereafter, the same operation as in Example 1 was performed to obtain manganese oxide having a Pt loading of 0.5% by weight and a Zr loading of 1.3% by weight.

Example 14 Zr was prepared in the same manner as in Example 4 except that 474 g of zirconyl sulfate having a concentration of 100 g / L was used.
Manganese oxide containing 62 g was obtained. The manganese oxide containing Zr had a specific surface area of 227 m ² / g and a Zr loading of 18.9% by weight. Thereafter, the same operation as in Example 1 was carried out to obtain a Pt loading of 0.5% by weight and a Zr loading of 18%.
9% by weight of manganese oxide was obtained.

Example 15 The procedure of Example 4 was repeated, except that the dinitrodiammine platinum nitrate solution was used in an amount of 0.001 g in terms of Pt. Manganese oxide having a Zr loading of 6.8% by weight was obtained.

Example 16 The procedure of Example 4 was repeated, except that the dinitrodiammineplatinic nitric acid solution was used in an amount of 0.1 g in terms of Pt. Zr loading 6.
8% by weight of manganese oxide was obtained.

COMPARATIVE EXAMPLE 1 121.8 g of manganese nitrate hexahydrate and 200 g of titanyl sulfate at a concentration of 100 g / L were dissolved in 100 mL of ion-exchanged water to prepare a mixed aqueous solution of manganese nitrate / titanyl sulfate. Separately, 40 g of potassium permanganate was dissolved in 200 mL of ion-exchanged water to prepare an aqueous potassium permanganate solution.

The above-mentioned mixed aqueous solution of manganese nitrate and titanyl sulfate was added dropwise to the aqueous solution of potassium permanganate with stirring, and the reaction was completed in about 30 minutes. The obtained reaction product was filtered, washed with ion exchanged water, dried, and
Manganese oxide containing 65 g was obtained. The manganese oxide containing Ti had a specific surface area of 170 m ² / g and a Ti loading of 6.2% by weight.

COMPARATIVE EXAMPLE 2 121.8 g of manganese nitrate hexahydrate was added to 100 parts of ion-exchanged water.
The solution was dissolved in mL to prepare an aqueous solution of manganese nitrate. Separately, 40 g of potassium permanganate was added to 200 parts of ion-exchanged water.
The solution was dissolved in mL to prepare an aqueous solution of potassium permanganate. The manganese nitrate aqueous solution was added dropwise to the potassium permanganate aqueous solution with stirring, and the reaction was completed in about 30 minutes. The obtained reaction product was filtered, washed with ion-exchanged water, and dried to obtain 61 g of manganese oxide. The specific surface area of this manganese oxide was 204 m ² / g.

Comparative Example 3 A dinitrodiammine platinum nitrate solution was added to 10 g of the manganese oxide prepared in Comparative Example 2 together with an appropriate amount of ion-exchanged water so as to obtain 0.05 g in terms of Pt, and the slurry was evaporated. After drying, manganese oxide having a Pt loading of 0.5% by weight was obtained.

(Adsorption Evaluation Test) Example 17 The adsorbents prepared in Examples 1 to 16 and Comparative Examples 1 to 3 were formed into granules as described below, and the adsorbent was used to evaluate the adsorption performance of sulfur compounds. An evaluation test was performed.

Preparation of Granular Adsorbent To 50 g of the manganese oxide powder obtained in Examples 1 to 16 and Comparative Examples 1 to 3, 50 g of silica sol (“Snowtex N” manufactured by Nissan Chemical Industries, Ltd.) and an appropriate amount of water were added. Was formed into granules, and the mesh size was reduced to 20 mesh under and 30 mesh over.

Test Method of Adsorption Rate As shown in FIG. 1, the test was carried out using an adsorber 1 filled with an adsorbent.
Is placed in a constant temperature bath 2 and propane gas or air containing the following sulfur compound is passed through the adsorber 1 under the following test conditions, and the sulfur compound concentration in the propane gas or air at the inlet and outlet of the adsorber is measured. The sulfur compound adsorption rate (%) was determined from the following equation: sulfur compound adsorption rate = [(inlet concentration-outlet concentration) / inlet concentration] × 100 (%).

The test conditions were based on the following conditions 1 or 2. Test condition 1 (Adsorption removal of dimethyl sulfide when the balance is propane) Gas composition: t-butylmethylcaptan 3 ppm dimethyl sulfide 3 ppm propane Balance temperature: 20 ° C. Space velocity (SV): 30,000 hr ⁻¹

Test condition 2 (adsorption and removal of hydrogen sulfide and methyl mercaptan when the balance is air) Gas composition: hydrogen sulfide 5 ppm methyl mercaptan 5 ppm air balance relative humidity 60% temperature: 20 ° C. space velocity (SV): 100,000 hr ^-1 Table 1 shows the results under test condition 1, and Table 2 shows the results under test condition 2.

[0046]

[Table 1]

[0047]

[Table 2]

[0048]

As described above, the adsorbent according to the present invention comprises:
A manganese oxide having a predetermined specific surface area and a diffraction angle (2θ) of a diffraction peak of the maximum intensity in X-ray diffraction at a predetermined angle is made to carry a predetermined active component, and a relatively small amount of hydrogen sulfide, mercaptans, and sulfides The sulfur compound can be efficiently adsorbed and removed from a gas containing a malodorous sulfur compound such as (sulfide). In particular, the adsorbent according to the present invention balances hydrocarbons, such as city gas and propane gas, and effectively adsorbs and removes relatively small amounts of sulfur compounds, especially methyl sulfide, which was conventionally difficult to remove by adsorption. can do. Of course, the adsorbent according to the present invention can efficiently adsorb such sulfur compounds from air containing sulfur compounds having bad smells generated in toilets and refrigerators, not only in the gas that balances hydrocarbons, but also in ordinary households. Can be removed.

Further, according to the adsorbent according to the present invention, it is needless to say that compared with the adsorbent consisting of only manganese oxide,
Compared to the adsorption carried by only one of the group A element or the group B element, for example, the adsorbent according to Example 1 is clearly compared with the adsorbent according to Comparative Examples 1 and 3, respectively. , The sulfur compound adsorption rate itself is high, and
There is almost no decrease in the adsorption rate with time,
That is, it has excellent durability.

[Brief description of the drawings]

FIG. 1 shows an experimental apparatus configuration for testing the adsorption performance of an adsorbent.

[Explanation of symbols]

 1. Adsorber, 2. Thermostat.

Claims (1)

[Claims] 1. A diffraction angle (2θ) of a diffraction peak having a maximum intensity in X-ray diffraction having a specific surface area of 50 m ² / g or more.
Is 37 ° ± 1 °, Ti, Zr, F
e, a sulfur compound adsorbent obtained by supporting at least one element selected from the group consisting of Cu, Ce and La and at least one element selected from the group consisting of Pt, Au and Pd. .