KR100558895B1 - Adsorbents for organic sulfur compounds, Method for manufacturing them and Method for desulfurizing of town gas using them - Google Patents

Abstract

The present invention relates to an adsorbent for removing organic sulfur compounds, a method for manufacturing the same, and a method for desulfurizing a city gas using the same, and an object of the present invention is to reform a city gas and use it as a fuel for a fuel cell.

The method for preparing an adsorbent for removing organic sulfur compounds according to the present invention is based on activated carbon as an adsorbent, and treated with acidic aqueous solution and washed with distilled water from Fe, Co, Ni, Cu, Zn, Ag. It is prepared by supporting one or two or more selected transition metals. Passing the fuel gas through the adsorbent prepared by the present invention can remove the organic compound in the fuel gas to a level of 0.1 ppm or less.

City gas, acid treatment, organic sulfur compound, transition metal, desulfurization, activated carbon, adsorbent

Description

Adsorbents for removing organic sulfur compounds and method for manufacturing the same and desulfurization method for city gas using the same {Adsorbents for organic sulfur compounds, Method for manufacturing them and Method for desulfurizing of town gas using them}

1 is a process chart of the manufacturing method of the adsorbent for removing organic sulfur compounds according to the present invention.

The present invention relates to an adsorbent for removing organic sulfur compounds, a method of manufacturing the same, and a desulfurization method of city gas using the same, and effectively adsorbs organic sulfur compound odorants contained in fuel gas to utilize fuel gas such as city gas as fuel for fuel cell. The present invention relates to an adsorbent for removing organic sulfur compounds, a method for preparing the same, and a method for desulfurizing city gas using the same.

The city gas used as fuel gas is t-Butylmercaptan (TBM), Tetrahydrothiophene (THT), Isopropyl mercaptan (Isopropyl mercaptan) A trace amount of organic sulfur compounds, such as IPM), is contained as an odorant. Currently, liquefied natural gas (LNG), which is supplied from Korea, is mixed with organic compound odorants of TBM and THT at a ratio of about 3: 7, and the concentration of odorants is about 4 ppm (15 mg / m ³ ). Known. The odorant of the organic compound is necessary in order to prevent accidents caused by gas leakage, but when used for the purpose of reforming city gas to produce hydrogen or syngas, it is poisoned by the reforming catalyst and causes the efficiency of the catalyst to be lowered. When the fuel gas for the fuel cell is manufactured by reforming the city gas, a desulfurization process using a desulfurization agent is required during the reforming process.

The fuel cell provides electricity through a chemical oxidation-reduction reaction, and much research has been conducted in developed countries such as the US, Japan, and Europe because it has a significant advantage over other forms of power generation in terms of cleanliness and efficiency. It is becoming. There are many kinds of fuel cells such as phosphoric acid fuel cell, polymer electrolyte fuel cell, molten carbonate fuel cell, solid oxide fuel cell, but most of them can use only hydrogen as fuel or even if not, hydrogen is used as the most advantageous fuel for power generation efficiency. have. In a fuel cell system using city gas as a primary fuel gas, the fuel reforming process for producing hydrogen is about one third of the total.

The fuel reforming process is a process for producing hydrogen from a city gas, which is a fuel gas, and a desulfurization process for removing an odorant, an organic sulfur compound contained in the city gas, and a reforming process for converting hydrocarbons into hydrogen (H ₂ ) and carbon monoxide (CO). This process consists of a water gas shift (WGS) process that converts CO into CO _2, and optionally a selective oxidation (PROX) process that lowers the residual CO in ppm.

If the organic sulfur compound odorants contained in trace amounts in the city gas are not removed, the life cycle of the reforming catalyst may be shortened by poisoning of the fuel reforming process, and the WGS process, the PROX process, and the electrode catalyst of the fuel cell after the reforming process. Shortening the catalyst life due to deactivation increases the cost of the fuel cell. Therefore, the desulfurization process is necessary in the fuel reforming process for producing hydrogen and syngas using city gas, and it is required to lower the concentration of sulfur in the fuel gas after desulfurization to 0.1 ppm or less.

Hydrogen desulfurization and a method using an adsorbent are known as methods for removing organic sulfur compounds which are odorants contained in fuel gases such as city gas. Hydrogen desulfurization method adds hydrogen to the fuel gas, decomposes the organic sulfur compound into hydrogen sulfide using a catalyst such as a Co-Mo catalyst, and decomposes the produced hydrogen sulfide with a desulfurization agent such as zinc oxide or iron oxide to give a sulfur concentration. Although it can be lowered to 0.1ppm, sulfur compounds of 0.1ppm concentration also adversely affect the fuel reforming process, so deep sulfurization is required to desulfurize the sulfur concentration below 0.1ppm. In addition, when used for a fuel cell, the desulfurization reactor cannot raise the start-up time because the temperature of the desulfurization reactor must be raised to 350 ° C., and a part of hydrogen produced through the reformer must be refluxed and fed to the desulfurization reactor. This is complicated.

On the other hand, a method using an adsorbent is a method of adsorbing and removing an organic sulfur compound by passing a fuel gas through an adsorbent containing activated carbon, a metal oxide, zeolite, or the like as a main component. Although the method with an adsorbent also raises an adsorption capacity by heating, the method of making it adsorb | suck at normal temperature is simpler and more preferable. The desulfurization method using an adsorbent at room temperature has the advantage of being suitable for fuel cells because it does not require heat or hydrogen, such as hydrodesulfurization or heat adsorption. At present, foreign countries recognize the importance of this technology and are widely studied in the United States, Japan, and Europe, and the result is protected by intellectual property rights. Osaka Gas Ltd. of Japan has been researching this field for more than 10 years, and they invented Cu-Zn manufactured by coprecipitation as a desulfurization adsorbent (US 6,042,798). In Tokyo Gas of Japan, Ag, Fe, Cu, which has good adsorption capacity of dimethyl sulfide (DMS), an activated carbon fiber adsorbent, which has greatly improved the adsorption and desulfurization ability of odorants contained in fuel gas, and odorants in Japanese city gas. An adsorbent obtained by ion-exchanging one or two transition metals, such as, Ni, Cu, and Zn, with a hydrophobic zeolite was disclosed (Japanese Patent Laid-Open No. 2001-19984, 2001-286753). Phillips Petroleum Company invented a desulfurization adsorbent consisting of ZnO, SiO ₂ , Al ₂ O ₃ , Ni, etc. and applied it to the desulfurization of gasoline or diesel (US 6,254,766).

Desulfurization adsorbents developed in Japan are focused on adsorptive desulfurization of DMS sulfur compound odorants contained in Japanese city gas, so there is a problem in that it is not efficient for adsorption desulfurization of TBM and THT used in domestic city gas. Also, when Ag, which is relatively expensive than Fe, Cu, and Zn, is used, it shows the best desulfurization adsorption performance, but it has a sulfur adsorption capacity of less than 2wt% (g _s / g _ads. ) And desulfurization agent by using a zeolite adsorbent. There is a problem that the price is high.

Activated carbon is classified into vegetable, coal and petroleum according to the raw materials, and is a collection of amorphous carbon with fine micropores. It is used as an adsorbent because it has a. However, activated carbon has many differences in price and physical properties depending on raw materials and activation methods. Commercially used activated carbon is manufactured from vegetable raw materials, and especially activated carbon produced by coconut shell is used. Activated charcoal contains various metal components contained in the plant raw material. Especially, it contains a large amount of alkali metal component, which prevents the adsorption of organic sulfur compounds, which are weak Lewis basic substances, similar to alkali metal characteristics in zeolite. Do it. In addition, since carbon disperses activated carbon prepared by gas activation in water, the solution shows a strong base. Therefore, when an aqueous solution of metal salt is added to activated carbon, metal-hydroxide [Fe- (OH) n, Cu- (OH) n] and The same precipitate is formed, which makes it difficult to uniformly disperse metal ions in activated carbon. In addition, the precipitate in the form of metal-hydroxide has a problem of reducing the specific surface area of the activated carbon by blocking the micropores present in the activated carbon, thereby lowering the adsorption capacity of the activated carbon.

The present invention for solving the above problems, to improve the adsorption capacity of the organic sulfur compound sorbents such as TBM, THT to effectively remove the sorbent for organic sulfur compound removal and city gas desulfurization method using the same. There is a purpose.

In order to achieve the object as described above, the method for preparing the adsorbent for removing organic sulfur compounds according to the present invention includes activated carbon as an adsorbent as a base material, Fe, Co, treated with activated carbon treated with an acidic aqueous solution and washed with distilled water. It is characterized by manufacturing by supporting one or two or more kinds of transition metals selected from Ni, Cu, Zn and Ag.

In the city gas desulfurization method using the adsorbent for removing the organic sulfur compound according to the present invention, the adsorbent is filled in the adsorption tube of the desulfurizer, the city gas is -20 to 200 ° C, the gauge pressure is 0.01 to 10 atm, and the space velocity is 100 to The organic sulfur compound in the city gas is removed by passing through the adsorbent under a condition of 50,000 h ⁻¹ .

The features and advantages of the present invention will become more apparent from the following detailed description based on the accompanying drawings. Prior to this, the terms or words used in the present specification and claims are based on the principle that the inventor can appropriately define the concept of the term in order to explain the invention in the best way. It should be interpreted as meanings and concepts corresponding to

In the method for preparing an adsorbent for removing organic sulfur compounds according to the present invention, a desulfurized adsorbent prepared by treating an adsorbent with an aqueous acid solution, washing it with distilled water so as to have a pH of 4 or more, and supporting a transition metal such as Fe and Cu in the washed activated carbon It relates to a manufacturing method.

Hereinafter, a method for preparing an adsorbent for removing organic sulfur compound odorants included in city gas according to the present invention will be described in detail with reference to FIG. 1.

(S10) Activated carbon acid treatment. The adsorbent according to the present invention is based on commercial activated carbon produced from coconut shell, which is a vegetable raw material. Since activated carbon contains various metal components in palm shell, which is a raw material of activated carbon, metal components from raw materials may be included, and various metal components may be included in the manufacturing process. Due to this problem, a washing process for removing various metal components and finely activated carbon particles contained in commercial activated carbon is necessary to prepare a uniform desulfurized adsorbent. Activated charcoal is placed in a washing container and distilled water is used to remove finely divided activated carbon and activated carbon having a relatively low density, and then treated with an aqueous acid solution. As the aqueous acid solution, nitric acid, hydrochloric acid, and sulfuric acid aqueous solutions may be used. Treatment of activated carbon with an aqueous solution of nitric acid as an aqueous acid solution removes metal components present in the activated carbon, and also forms functional groups such as carboxyl groups (-COOH) on the surface of the activated carbon. When functional groups such as carboxyl groups are formed on the surface of activated carbon, transition metals such as Fe and Cu may be uniformly dispersed on the surface of activated carbon when supported by ion exchange or impregnation.

(S20) activated carbon wash. The activated carbon treated with an aqueous acid solution is washed with distilled water so that the pH of the washing solution is 4 or more.

(S30) supported. A desulfurized adsorbent is prepared by supporting a transition metal such as Fe and Cu by impregnation and ion exchange in an activated carbon treated with an aqueous acid solution.

At this time, water-soluble salts such as nitrates, acetates, sulfates, carbonates, etc. are used as metal materials, and when activated metals are impregnated with activated carbon, put activated carbon treated in aqueous metal salt solution at room temperature and then aged for 12 to 24 hours. The method of supporting the transition metal may be an impregnation method or an ion exchange method.

The aqueous metal salt solution used for the impregnation method is suitably used in 1 mL per 1 gram (g) of activated carbon.

(S40) dry. Activated carbon aged through a supporting step is prepared by drying in a 100 ~ 200 ℃ preferably 150 ℃ drying oven for 12 to 24 hours. Commercial activated carbon washed with distilled water to have a pH of 4 or more is dried in a drying oven at 100-200 ° C., preferably 150 ° C. for 12-24 hours, and stored in a sealed container for use. During the drying process, the activated carbon adsorbs other materials, so it needs to be kept dry and stored.

In the case of using the ion exchange method, the mixture is dried at 150 ° C. for 12 to 24 hours after ion exchange, washing and filtering for 12 to 24 hours at room temperature (RT) to 80 ° C. temperature range.

(S50) firing. The dried activated carbon is calcined under a temperature condition of 200 to 700 ° C.

(S60) Completed adsorbent for removing organic sulfur compounds. Through the process of (S10) ~ (S50) to complete the adsorbent for removing organic sulfur compounds.

 The present invention is not limited to the method for producing a desulfurized adsorbent using commercially available activated carbon as described above, and other known production methods may be appropriately applied, if necessary, in addition to the above-described methods.

The adsorbent for removing organic sulfur compounds according to the present invention is activated carbon as a base material, and one or two or more transition metals selected from Fe, Co, Ni, Cu, Zn and Ag in activated carbon treated with an acidic aqueous solution and washed with distilled water. Characterized by the material produced by carrying. Existing activated carbon contains 0.3-0.5wt% aluminum (Al), magnesium (Mg), calcium (Ca), phosphorus (P) and about 2wt% potassium (K). The basic metal component of the existing activated carbon not only inhibits the adsorption of the organic sulfide, which is a Lewis base, but also disperses the activated carbon in water in the process of supporting the metal, so that the solution shows a strong base. Precipitates such as side [Fe- (OH) n, Cu- (OH) n] are formed, which makes it difficult to uniformly disperse metal ions in activated carbon. In addition, the precipitate in the form of metal-hydroxide has a problem of reducing the specific surface area of the activated carbon by blocking the micropores present in the activated carbon, thereby lowering the adsorption capacity of the activated carbon. However, in the activated carbon adsorbent treated with an aqueous acid solution, only carbon (C) and oxygen (O) components remain to solve this problem. In addition, oxygen (O) content is increased after nitric acid treatment because new carboxyl groups (-COOH) are formed on the surface of activated carbon. The functional groups such as carboxyl groups produced by nitric acid treatment not only increase the adsorption capacity of the organic sulfur compound but also provide a site on which activated metal can be supported by ion exchange. In addition, even when the metal is supported by the impregnation method, the functional groups generated on the surface of the activated carbon have an effect of increasing the dispersibility of the metal to mitigate the reduction of micropores (<2 nm) present in the activated carbon by the metal salt. By this effect, the adsorption capacity of the organosulfur compound is improved by 3 to 4 times that of conventional activated carbon.

By using the organic sulfur compound removal adsorbent prepared by the method for preparing the organic sulfur compound removal adsorbent according to the present invention can remove the organic sulfur compound contained in the city gas can be used as a fuel for fuel cells, desulfurization of the city gas according to the present invention In the method, the adsorbent according to the present invention is filled into an adsorption tube inside a desulfurizer, and the inside of the desulfurizer is subjected to city gas under conditions of a temperature of -20 to 200 ° C., 0.01 to 10 atm, and a space velocity of 100 to 50,0000 h ⁻¹ . Is passed through an adsorbent to adsorb and remove organic sulfur compound odorants (such as TBM and THT).

In the desulfurization experiment, a conventional fixed bed adsorption desulfurization apparatus was used, and the particles of the adsorbent were treated with an aqueous acid solution and filled with activated carbon (particle size: 8 * 30 mesh) loaded with metal into an adsorption tube to prepare a desulfurizer.

The organic sulfur compound odor removal test contained in the city gas was implemented using the fixed bed desulfurizer. The test conditions were 1 mL of desulfurization agent, pressure at normal pressure (about 1 atm pressure: about 1013.25 hPa (hectopascal)), reaction tube inlet temperature at room temperature (15-30 ° C), gas hourly space velocity: catalyst unit per hour. Process gas volume per volume (m ³ / m ³ .h)) is 100 to 50,000 h ⁻¹ , and the gas used is a CH ₄ gas containing 22.3-22.9 ppm TBM and 55.6-55.9 ppm THT odorant. During the test, the sulfur (S) concentration of the gas discharged from the reaction tube outlet was measured using the on-line gas chromatograph equipped with a pulsed flame photometric detector (PFPD). The breakthrough curve was obtained, and the time from the time when the gas containing the organic sulfur compound odorant was started to flow to the desulfurization unit was measured to determine the saturation time. Since the degree of adsorption to the adsorbent varies depending on the type of organic sulfur compound, the amount of adsorption of TBM and THT is calculated until the time when the concentration is first detected at a concentration of 0.1 ppm or higher among the TBM or THT components used as odorants. The concentration of was calculated as the desulfurization performance (wt% g _s / g _ads. ) Of the desulfurization adsorbent.

The invention is explained in more detail by the following examples, which are not intended to limit the invention.

<Example 1>

Put about 2/3 of commercial activated carbon (particle size: 8 * 30mesh) into a washing container in distilled water, remove finely divided activated carbon particles and relatively dense activated carbon particles, and then use 12M water at 80 ℃ using 5M nitric acid solution. Acid treatment for time. The activated carbon treated with nitric acid solution was washed with distilled water so that the pH of the washing solution was 4 or higher, and then filtered and dried under vacuum at 150 ° C for 12 hours. 5 wt% copper (Cu) -activated carbon adsorbent was prepared by impregnating the dried activated carbon. 1.97 g of copper nitrate trihydrate (Cu (NO ₃ ) ₂ · 3H ₂ O) was dissolved in 10 mL of distilled water to prepare a clear copper salt solution, and 10 g of dried activated carbon was added to the prepared copper salt solution, followed by aging at room temperature for 24 hours ( aging) and vacuum drying at 150 ° C. for 12 hours to prepare Cu-activated carbon having 5 wt% of copper (Cu (II)).

After measuring the bulk density of Cu-activated carbon adsorbent loaded with 5wt% of copper, 1mL of adsorbent was filled into a 1cm inner diameter quartz tube and pretreated for 3 hours at 200 ° C while flowing 30mL (30mL / min) of nitrogen per minute. Cooled to room temperature. And, methane (CH ₄ ) gas containing 23.4ppm and 55.6ppm of odorant TBM and THT at room temperature and atmospheric pressure, respectively, is passed through the adsorption tube at a space velocity of GHSV 6,000h ⁻¹ to discharge sulfur compounds in methane gas. It was measured using PFPD-GC. The desulfurization adsorption performance was the adsorption time of the organosulfur compound up to the time when the concentration was first detected at a concentration of 0.1 ppm or more in TBM or THT. During the adsorption time of sulfur compounds, the adsorption capacity of sulfur components was calculated from the adsorption amount of TBM and THT organic sulfur compounds. The adsorption performance of the desulfurization adsorbent (wt% g _s / g _ads. ) _Was shown in Table 1 below.

<Example 2>

An adsorbent was prepared as in Example 1, but 10 g of dried activated carbon was added to an aqueous copper salt solution, and then aged at room temperature for 24 hours, followed by washing with distilled water at about 100 mL to remove unionized copper ions. The desulfurization adsorption performance of the prepared desulfurization adsorbent was tested in the same manner as in Example 1, and the results are shown in Table 1 below.

<Example 3>

5 wt% of Fe (III) metal was impregnated on the acid treated activated carbon as in Example 1. 3.88g iron nitrate hydrate (Fe (NO ₃ ) ₃ · 9H ₂ O) was dissolved in 10 mL of distilled water to prepare a clear iron salt solution, and 10 g of activated carbon prepared by acid treatment in the prepared iron salt solution as in Example 1 was added at room temperature. After aging for 24 hours and dried for 12 hours in a vacuum drying oven at 150 ℃ to prepare a Fe-activated carbon adsorbent with 5wt% iron. The desulfurization adsorption performance of the prepared desulfurization adsorbent was tested in the same manner as in Example 1, and the results are shown in Table 1 below.

<Example 4>

The adsorbent was prepared in the same manner as in Example 3, and the desulfurization adsorption performance was measured, but after firing the adsorbent 1 mL and calcining at 400 ° C. for 5 hours while flowing 5% H ₂ / N ₂ at a flow rate of 30 mL / min. The desulfurization adsorption performance was tested by cooling and the results are shown in Table 1 below.

<Example 5>

 Put commercial activated carbon (particle size: 8 * 30mesh) made of coconut shell into a washing container about 2/3, remove finely divided activated carbon particles and relatively small activated carbon particles with distilled water, and then use 0.1M aqueous hydrochloric acid solution for 12 hours at room temperature. Acid treatment. The activated carbon treated with an aqueous hydrochloric acid solution was washed with distilled water so that the pH of the washing solution was 4 or higher, and then filtered and dried under vacuum at 150 ° C. for 12 hours. 5 wt% copper (Cu) -activated carbon adsorbent was prepared by the same method as in Example 1 in the dried activated carbon.

The desulfurization adsorption performance of the prepared desulfurization adsorbent was tested in the same manner as in Example 1, but during the firing, 5% H ₂ / N ₂ was flowed at a flow rate of 30 mL / min, followed by calcination at 400 ° C. for 3 hours, followed by desulfurization adsorption performance. Was tested and the results are shown in Table 1 below.

<Example 6>

2/3 of commercial activated carbon (particle size: 8 * 30mesh) made of coconut shell is placed in a washing container, and fine powder of activated carbon and particles of relatively small density of activated carbon are removed with distilled water, followed by 1M nitric acid solution for 6 hours at room temperature. Acid treatment. The activated carbon treated with nitric acid solution was washed with distilled water so that the pH of the washing solution was 4 or higher, and then filtered and dried under vacuum at 150 ° C. for 12 hours. 1 wt% silver (Ag) -activated carbon adsorbent was prepared by impregnating the dried activated carbon. 0.157 g silver nitrate (AgNO ₃ ) was dissolved in 10 mL of distilled water to prepare an aqueous solution of silver nitrate. 10 g of dried activated carbon was added to the prepared aqueous solution of silver nitrate, and aged at room temperature for 24 hours. Cu-activated carbon having 5 wt% of (Cu (II)) was prepared.

The desulfurization adsorption performance of the prepared desulfurization adsorbent was tested in the same manner as in Example 1, but after firing and cooling at 300 ° C. for 3 hours while flowing nitrogen at a flow rate of 30 mL / min, the desulfurization adsorption performance was tested. It is shown in Table 1 below.

<Comparative Example 1>

Commercial activated carbon (8 * 30mesh) made of coconut shell was subjected to desulfurization adsorption test without acid treatment and metal support. Desulfurization adsorption test was carried out in the same manner as in Example 1, and the results are shown in Table 1 below.

<Comparative Example 2>

Copper (Cu (II))-activated carbon adsorbent was prepared by supporting 5wt% copper (Cu) by impregnation without commercially treating the activated activated carbon (8 * 30mesh). 1.97 g of copper nitrate trihydrate (Cu (NO ₃ ) ₂ · 3H ₂ O) was dissolved in 10 mL of distilled water to prepare a clear copper salt solution, 10 g of activated carbon was added to the prepared copper salt solution, and aged at room temperature for 12 to 24 hours. aging) and vacuum drying at 150 ° C. for 12 hours to prepare Cu-activated carbon adsorbent having 5 wt% of copper (Cu (II)). Desulfurization adsorption test was carried out in the same manner as in Example 1, and the results are shown in Table 1 below.

<Table 1>

division Adsorption performance (TBM + THT, wt% g _s / g _ads. ) ^A Example 1 9.35 Example 2 8.46 Example 3 7.52 Example 4 8.63 Example 5 7.95 Example 6 7.83 Comparative Example 1 2.34 Comparative Example 2 4.22 ^a adsorption performance (wt% g _s / g _ads ) = weight of adsorbed sulfur compounds / adsorbent mass x 100

Methane (CH ₄ ) gas used in the present invention is the main component of the city gas used in Korea, and the organic sulfur compound TBM and THT odorant are also odorant components used in domestic city gas. Since the city gas contains about 4 ppm of deodorant, it takes much time to apply the city gas directly in the manufacture and evaluation experiment of the desulfurization adsorbent. Therefore, the desulfurization adsorbent using methane gas having a high deodorant concentration was tested.

As shown in Table 1, when the activated carbon was treated in Examples 1 to 6 and the metal was supported on the activated carbon washed to have a pH of 4 or more, the adsorption desulfurization performance was greatly increased than that of Comparative Example 1 and Comparative Example 2. You can check. When activated carbon adsorbent is treated with an acid solution such as nitric acid, impurities such as alkali metals are removed. As a result of energy dispersive X-ray spectrometer (EDS) analysis, 0.3 to 0.5 wt% of aluminum (Al ), Magnesium (Mg), calcium (Ca), phosphorus (P) and about 2wt% potassium (K), but only carbon (C) and oxygen (O) components were analyzed in activated carbon adsorbents treated with an acid solution. . In addition, at least 94 wt% of carbon (C) and about 4 wt% of oxygen (O) were analyzed in the activated carbon before nitric acid treatment, but about 92 wt% of carbon (C) and 8 wt% of oxygen (O) were analyzed in the activated carbon after nitric acid treatment. The increase in the content of oxygen (O) in the activated carbon after nitric acid treatment is thought to increase the content of oxygen (O) because the carbon-carbon bond on the surface of the amorphous activated carbon is broken to form a new carboxyl group (-COOH). Functional groups, such as carboxyl groups produced by nitric acid treatment, provide the activated carbon with sites on which metals can be supported by ion exchange. In addition, even when the metal is supported by the impregnation method as in the above embodiment, the functional groups generated on the surface of the activated carbon may increase the dispersibility of the metal to mitigate the reduction of micropores (<2 nm) present in the activated carbon by the metal salt. It works. By this effect, the desulfurization adsorption performance of the example is greatly increased than that of Comparative Example 2. As shown in Table 1, when the transition metal is supported on the activated carbon in Examples 1 to 6, the adsorption power of the organic sulfur compound is enhanced by chemical bonding to the supported metal, so that the metal-supported adsorbent has excellent adsorption performance.

As described above, according to the present invention, the adsorbent for removing organic sulfur compounds, a method for preparing the same, and a desulfurization method for city gas using the same can effectively adsorb and desulfurize the organic sulfur compound TBM and THT odorant components contained in the city gas. By using a low cost activated carbon adsorbent, a low cost desulfurized adsorbent can be developed. The activated carbon is treated with an aqueous acid solution to increase the functional groups on the surface of the activated carbon, and the increased functional groups increase the dispersibility of the metals supported to have excellent desulfurization adsorption capacity. A good desulfurization adsorbent can extend the exchange cycle of desulfurization adsorbent to prolong the life of fuel reforming catalyst and fuel cell catalyst.

While the invention has been described and illustrated in connection with a preferred embodiment for illustrating the principles of the invention, the invention is not limited to the configuration and operation as such is shown and described. Rather, it will be apparent to those skilled in the art that many changes and modifications to the present invention are possible without departing from the spirit and scope of the appended claims. Accordingly, all such suitable changes and modifications and equivalents should be considered to be within the scope of the present invention.

Claims (7)

(S10) activated carbon acid treatment step of treating activated carbon with an aqueous acid solution; (S20) washing step of washing the activated carbon after the acid treatment step with distilled water to have a pH of 4 or more; (S30) a supporting step of supporting the activated carbon washed through the washing step in one or two or more transition metal compounds selected from Fe, Co, Ni, Cu, Zn, Ag; (S40) a drying step of drying the activated carbon on which the transition metal compound is loaded at a temperature of 100 to 200 ^° C. through the supporting step; (S50) Method for producing an adsorbent for removing organic sulfur compounds, characterized in that it comprises a firing step of firing the activated carbon dried through the drying step at a temperature of 200 ~ 700 ^o C in an inert gas atmosphere or a reducing gas atmosphere. The method of claim 1, wherein in the active carbon acid treatment step, an organic sulfur compound removal method for producing an organic sulfur compound, characterized in that the acid treatment. The method of claim 1 or 2, wherein the activated carbon acid treatment comprises acid treatment of the activated carbon using any one of an aqueous acid solution selected from nitric acid, hydrochloric acid, and sulfuric acid aqueous solution. The method of claim 3, wherein in the supporting step, an adsorbent for removing organic sulfur compounds, characterized in that supported by any one of transition metal compounds of nitrate, acetate, carbonate of the transition metal. 5. The method of claim 4, wherein in the supporting step, an aqueous solution of a transition metal compound is supported by an impregnation method or an ion exchange method. An adsorbent for removing organic sulfur compounds, which is prepared by the method of any one of claims 1 to 5. The adsorbent according to claim 6 is filled in the adsorption tube of the desulfurizer, and the city gas is passed through the adsorbent under the conditions of -20 to 200 ° C, a gauge pressure of 0.01 to 10 atmospheres, and a space velocity of 100 to 50,000 h ^-1 . A method for desulfurization of city gas using an organic sulfur compound removal adsorbent, characterized in that the organic sulfur compound is removed.

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