JP2580166B2 - Dry desulfurization adsorbent - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to hydrogen sulfide (hereinafter referred to as H ₂ S) contained in fuel gas and the like.
And desulfurization adsorbents applied to the removal of carbonyl sulfide (hereinafter referred to as COS).

[Conventional technology]

Conventionally, iron oxide is often used as a desulfurizing agent at a high temperature of fuel gas. This is based on the reaction of [absorption] Fe ₂ O ₃ + 2H ₂ S + H ₂ → 2FeS + 3H ₂ O (1) [regeneration] 4FeS + 7O ₂ → 2Fe ₂ O ₃ + 4SO ₂ (2) H ₂ S
Is removed as iron sulfide, the air reacts with the iron sulfide to regenerate the iron oxide, and is reused as a desulfurizing agent.

Iron oxide, alumina, calcia, silica, titania,
Among clays and the like, it is supported on a carrier consisting of at least one or more powdery or fluidized bed, moving bed or fixed bed.
It is used as a desulfurizing agent in various shapes such as granules.

Iron oxide-supported desulfurizing agents do not deteriorate over time as compared to granulated iron oxide or pulverized and classified oxides, but if the regeneration temperature is not limited, the performance will deteriorate, and if the regeneration temperature is suppressed, However, the playback speed is slow and impractical.

[Problems to be solved by the invention]

The present invention provides a dry adsorption remover of hydrogen sulfide and / or carbonyl sulfide which does not have the above-mentioned disadvantages as in the conventional method.

[Means for solving the problem]

The present inventors have studied various carrier materials and noticed that the carrier obtained by preliminarily treating a group IV metal hydroxide or metal oxide with a sulfate-containing treating agent and then calcining has excellent heat resistance. However, as a result of various experimental studies, it has been found that an adsorbent in which iron oxide is supported on a carrier obtained by preliminarily treating a substance containing zirconium hydroxide with a sulfate-containing treating agent and then calcining is H ₂ S and / or The inventors have found that COS is excellent in adsorption / regeneration and has good heat resistance, and has completed the present invention.

That is, the present invention provides that a carrier obtained by preliminarily treating a substance containing zirconium hydroxide with a sulfate-containing treating agent and then calcining the carrier contains 10 to 40% by weight of iron oxide based on the desulfurization adsorbent. It is a characteristic dry desulfurization adsorbent.

Here, the substance containing zirconium hydroxide refers to a substance containing at least 50% by weight of zirconium hydroxide as a main component and other components such as alumina, titania, and silica.

The term "sulfuric acid-containing treating agent" refers to a treating agent containing a sulfuric acid group such as sulfuric acid or ammonium sulfate.

The present invention relates to a method for adsorbing and removing H ₂ S and / or COS from a coke oven gas, a natural gas, a gasification furnace gas, etc., in which a gas containing zirconium hydroxide is previously treated with a sulfate-containing treating agent. After the treatment, a substance containing zirconium oxide obtained by calcining is used as a carrier and iron oxide is added to the carrier in an amount of 10 to 40 wt% (hereinafter, wt% is based on the desulfurization adsorbent)
A desulfurization adsorbent that can be heated and regenerated in the presence of oxygen after H ₂ S in the gas is brought into contact with the adsorbent and absorbed and removed in the adsorbent.

The present invention improves adsorption capacity and desorption ability in desulfurization process, and aims to improve the heat resistance and SO _X resistance, containing Jirukonimu hydroxide treated with sulphate ion-containing treatment agent The object has been achieved by using a substance containing zirconium oxide obtained by calcining the substance as a carrier and loading 10 to 40% by weight of iron oxide.

As an example of a method for preparing the above-mentioned dry desulfurization adsorbent, a carrier obtained by treating a commercially available zirconium hydroxide powder with 1 N sulfuric acid for 30 minutes, washing with water, firing at 600 ° C, and molding, is used to add a ferric nitrate aqueous solution. , And then dried and fired to carry iron oxide. Its loading is 10 to 40% by weight.

Here, the reason why the loading amount is limited is that if it is less than 10%, the adsorption performance is not sufficient, and if it exceeds 40% by weight, the pores are closed, so that no improvement in performance can be seen.

The reaction is performed at 300 to 600 ° C., preferably 400 to 500 ° C.
Performed at ° C.

[Comparative Example 1]

Commercially available zirconium hydroxide powder at 600,700,800 ° C
After a time treatment, the specific surface area was measured. Table 1 shows the results.

[Example 1] A commercially available zirconium hydroxide powder was treated with twice the amount (by weight) of 1N sulfuric acid for 30 minutes, and then washed with water to 600,70.
After treatment at 0,800 ° C. for 15 hours, the specific surface area was measured. Table 1 shows the results.

[Comparative Example 2] F with commercial zirconium oxide pellets (3 mmφ)
The resultant was impregnated with an aqueous ferric nitrate solution so that the content of e ₂ O ₃ became 25% by weight, dried, and then calcined at 450 ° C. for 3 hours.

The adsorbent prepared by the above method was subjected to a desulfurization reaction under the test conditions shown in Table 2. Table 3 shows the results.

Example 2 A pellet (3 mmφ) extruded from zirconium oxide powder prepared by the method of Example 1 (at 600 ° C.) was loaded with Fe ₂ O ₃ in the same manner as in Comparative Example 2; The desulfurization reaction was performed under the test conditions shown in the following. Table 3 shows the results.

Comparative Example 3 The desulfurizing agent prepared in Comparative Example 2 was regenerated at 600 ° C. after the desulfurization reaction, and the desulfurization test was performed again. Table 3 shows the results.

Example 3 The desulfurizing agent prepared in Example 2 was regenerated at 600 ° C. after the desulfurization reaction, and the desulfurization test was performed again. Table 3 shows the results.

From Tables 1 and 3, the heat resistance of zirconium oxide which is a carrier material of the desulfurizing agent of the present invention is clearly improved,
From Example 2, it can be seen that even when iron oxide is supported, it has substantially the same desulfurization performance as a desulfurizing agent comprising an untreated zirconium oxide carrier. Further, the desulfurizing agent of the present invention (Example 3) treated at 600 ° C. was not deteriorated, and a desulfurizing agent having heat resistance was obtained.

H ₂ S10% leakage and H ₂ S20% leakage Table 3 in the unreacted H ₂ S in the respective gas after desulfurization becomes 10% and 20% of H ₂ S in the prior desulfurization gas Represents the time until

〔The invention's effect〕

As is clear from the results of the examples, the dry desulfurization adsorbent of the present invention is a desulfurization agent having good adsorption performance and heat resistance.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Koichi Numata 4-6-22 Kannon Shinmachi, Nishi-ku, Hiroshima City Inside the Hiroshima Research Laboratory, Sanishi Heavy Industries Co., Ltd. No. 3 Hiroshi Heavy Industries, Ltd.

Claims (1)

(57) [Claims] 1. A carrier obtained by preliminarily treating a substance containing zirconium hydroxide with a sulfate-containing treating agent and then calcining the carrier to carry 10 to 40% by weight of iron oxide based on the desulfurization adsorbent. A dry desulfurization adsorbent characterized by the following.