JP2008246432A - Mercury removing adsorbent using iron oxide subjected to sulfurization treatment and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an adsorbent for removing gaseous mercury after sulfurization treatment of iron oxide to accumulate sulfur and further to provide its manufacturing method. <P>SOLUTION: The mercury removing adsorbent containing iron oxide subjected to sulfurization treatment with sulfurization treatment gas which is composed of 0.001 to 2 vol.% of sulfur compounds, 1 to 50 vol.% of oxygen and 48.0 to 98.999 vol.% of carrier gas on the basis of the whole volume of the sulfurization treatment gas, is provided. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an adsorbent for removing mercury by adsorbing and removing mercury, and more particularly to an adsorbent for removing mercury using iron oxide sulfided with a sulfurizing gas containing a sulfur compound and oxygen and a method for producing the same. .

  Since the industrial revolution, environmental problems have been deepening rapidly with the acceleration of industrialization. In particular, heavy metals emitted from pollution sources are causing great concern. Among them, mercury is a pollutant that is of further interest due to its high volatility, strong toxicity and accumulation characteristics in the body, which is different from other heavy metals, and if it is released into the atmosphere from a combustion device, Unlike other heavy metals that are discharged in the form of gases, it is known that they are mainly discharged in the gaseous state of the elemental state.

  Currently, according to the EPA (The US Environmental Protection Agency) publication materials, methods for removing mercury include activated carbon injection, carbon filter beds, selenium filters, There are various methods such as activated activated carbon adsorption and wet scrubbing, and many methods using activated carbon have been studied. However, this method is expensive because about 100,000 g of activated carbon must be used to remove 1 g of mercury, and physically adsorbed mercury may be desorbed from the activated carbon. There are problems such as having to seal and landfill.

  Methods for using sulfur to remove mercury have been studied by various researchers, and studies on adding sulfur on oxides or hydroxides are also actively conducted. In addition to the method of adding sulfur to activated carbon, recently, a method of adding mercury to a mesoporous material to remove mercury has also been developed. However, this method is expensive and has limited commercialization.

  Therefore, in this patent, iron oxide that can be produced at a low price among oxides is used as a mercury adsorbent, and the iron oxide itself is inferior in its ability to adsorb mercury, so the mercury adsorption performance is maximized by sulfur treatment. Try to become.

  From the viewpoint of sulfur treatment, harmful sulfur hydrogen is discharged from industrial fields such as incinerators and landfill power plants. When this sulfur hydrogen is discharged into the atmosphere as an air pollutant, it must be exhausted after being removed in accordance with the emission regulation value. Iron oxide can be used as an adsorbent for removing such sulfur hydrogen, and as a result, sulfur can be naturally added to the iron oxide. Utilizing such a principle, there is a synergistic effect of removing air pollutants in sulfur treatment of low-valent iron oxides, and resource recycling that can later use the waste adsorbent as further mercury adsorbent The effect can also be brought about.

  On the other hand, in recent years, while interest in environmental conservation and resource recycling has been concentrated, interest in recycling of various industrial wastes has increased. In particular, waste iron oxide, which occupies a high percentage of industrial waste generation, Although there is a high level of interest in recycling, the waste of resources due to landfilling due to the minute development of technology for recycling is a serious situation.

  In particular, ferrous sulfate and ferric sulfate are mainly produced as iron oxide pigments by hydrolysis or alkali treatment, or they themselves are used as flocculants for wastewater treatment, and in some cases magnetic materials and It is used as ferrite, but it is disposed of because there is not enough demand and demand compared to the amount of ferrous sulfate and ferric sulfate generated from the production process of steel and titanium dioxide. In the case of polyferric sulfate, there is a problem that the amount to be processed is a large amount. The composition of such a ferric sulfate solution is shown in Table 1.

  The iron oxide is usually generated as a by-product during the treatment of the solution generated from the process of washing the surface scale and contaminants with 18% hydrochloric acid in order to produce hot-rolled steel sheets into cold-rolled steel sheets in the iron making process. Alternatively, it can be produced from polyferric sulfate generated from a step of producing titanium oxide by a sulfuric acid method.

European Patent EP 1 308 198 (B1) US Patent US 6,328,939 (B1)

Therefore, the present inventors pay attention to the point that when removing mercury, iron oxide that can be supplied at a low price is synthesized, and the iron oxide can be used as a mercury adsorbent by sulfidation. The present invention has been completed.
The present invention has been derived in order to overcome the above-described problems, and its object is to provide an adsorbent for removing mercury containing an acid oxide that has been sulfurized with a sulfurizing gas containing a sulfur compound and oxygen. And providing a manufacturing method thereof.

  Another object of the present invention is to synthesize iron oxide from polyferric sulfate produced in a production process of titanium oxide using ilmenite as the iron oxide, and sulfidize the synthesized iron oxide. Accordingly, an object of the present invention is to provide a mercury removing adsorbent capable of adsorbing and removing mercury contained in exhaust gas and a method for producing the same.

  In order to achieve the above object, according to an aspect of the present invention, the sulfur compound is 0.001 to 2% by volume, the oxygen is 1 to 50% by volume, and the carrier gas is 48.0 to 98 based on the total volume of the sulfurized gas. The present invention provides an adsorbent for removing mercury containing iron oxide that has been sulfurized with a sulfurizing gas comprising 999% by volume.

  According to another aspect of the present invention, iron oxide is obtained from 0.001 to 2 vol% sulfur compound, 1 to 50 vol% oxygen, and 48 to 98.999 vol% carrier gas, based on the total volume of the sulfiding gas. And a method for producing an adsorbent for removing mercury, comprising the sulfurization treatment with a sulfurization treatment gas.

Mercury to be treated by the mercury-removing adsorbent according to the present invention means general vapor-phase mercury, but is preferably contained in exhaust gas, particularly preferably exhaust gas discharged from a power plant, an incinerator, or the like. Phase mercury, or vapor such as a mercury battery using mercury, fluorescent lamp such as a mercury fluorescent lamp, or vapor phase mercury discharged from a dental amalgam, specifically Hg ^{0 of} the vapor phase mercury, It means vapor phase mercury containing HgCl and HgCl ₂ .
Here, the Hg ⁰ means pure Hg, that is, elemental mercury.

The iron oxide constituting the mercury-removing adsorbent according to the present invention can be any iron oxide, for example, FeO, Fe (OH) ₂ , Fe (OH) ₃ , as long as it can be used as an adsorbent after being sulfurized. FeO (OH), Fe ₂ O ₃ , Fe ₃ O ₄ or the like may be used, and preferably includes an FeO (OH) structural formula having amorphous spherical particles.

  On the other hand, the iron oxide according to the present invention can use iron oxide specifically manufactured from polyferric sulfate, and the manufacturing method of iron oxide manufactured from polyferric sulfate is more simplified. First, ferric polysulfate and an aqueous alkali solution are prepared at appropriate concentrations, and a suspension is produced by mixing and stirring. A product is obtained from the prepared suspension through a filtration and washing step, and then a drying step to produce iron oxide as a final product.

Here, the polyferric sulfate may be any polyferric sulfate commonly used in the industry, but preferably polysulfuric acid produced in the step of producing titanium oxide using ilmenite. Iron oxide (Fe ₂₎ generated in the form of waste slag from the pickling process in the production process of polyferric sulfate or steel produced from solid ferrous sulfate, which is a by-product of ferric and titanium oxide. Any polyferric sulfate produced by mixing O ₃ ) with water and sulfuric acid may be used, and more preferably poly produced in the step of producing titanium oxide using ilmenite. It is better to use ferric sulfate.

  In particular, iron oxide synthesized from ferrous sulfate and ferric sulfate for materials or pigments has very poor physical properties as an adsorbent. However, when an iron oxide is produced by the method of the present invention, an iron oxide having physical properties superior to those of existing iron oxides can be produced.

On the other hand, as the alkaline aqueous solution according to the present invention, any material can be used as long as it can neutralize the ferric sulfate. [(NH ₄ ) ₂ CO ₃ ], ammonium bicarbonate (NH ₄ HCO ₃ ), ammonia (NH ₃ ), sodium hydroxide (NaOH) or mixtures thereof can be used, particularly preferably ammonium bicarbonate or Sodium hydroxide is preferably used.

  On the other hand, the mercury removing adsorbent according to the present invention produces iron sulfide and elemental sulfur by contacting iron oxide produced from polyferric sulfate with a sulfur-containing gas. Here, the formed iron sulfide and elemental sulfur react with vapor phase mercury to form mercury sulfide (HgS).

  The method for sulfur treatment of iron oxide according to the present invention to form iron sulfide may be any method as long as iron oxide is exposed to a gas containing a sulfur compound and oxygen, that is, a sulfurization treatment gas. . As a method of exposing the iron oxide to the sulfur-containing gas, elemental sulfur is vaporized at a high temperature and exposed to iron oxide together with oxygen to form iron sulfide, and / or the iron oxide is oxygenated into a gas such as hydrogen sulfide. Although it is possible to use a method of adsorbing hydrogen sulfide itself by exposing it together, preferably iron oxide is exposed to a mixed gas of hydrogen sulfide and oxygen to treat malodorous hydrogen sulfide and simultaneously form iron sulfide. It is good to let them.

  Here, the sulfidizing gas for sulfiding the iron oxide is 0.001 to 2% by volume of a sulfur compound, preferably about 1% by volume, 1 to 50% by volume of oxygen, based on the total volume of the sulfidizing gas. Preferably, the carrier gas comprises 3 to 20% by volume and carrier gas 48 to 98.999% by volume, and the carrier gas is a carrier gas commonly used in the industry, such as nitrogen and / or landfill power plant, essential oil factory, human feces treatment It is preferable to use gas generated from factories, sewage treatment plants, and the like.

At this time, since sulfurization treatment of iron oxide using the sulfur compound is an exothermic reaction, the sulfur compound should not exceed 2% by volume, preferably about 1% by volume, based on the total volume of the sulfurization gas. .
In the sulfur treatment according to the present invention, not only a sulfur compound but also oxygen is used to treat iron oxide. As shown in the following reaction formula 1 and reaction formula 2, oxidation is performed with a sulfur compound in an oxygen atmosphere. When iron is sulfided, the iron oxide does not change substantially and only sulfur accumulates in the voids of the iron oxide (see reaction formula 1), but the iron oxide is treated with a sulfur compound in an oxygen-free atmosphere. , Iron oxide changes to iron sulfide (Scheme 2)

[Reaction Formula 1]
2FeO (OH) + 3H ₂ S → FeS + FeS ₂ + 4H ₂ O
FeS + FeS ₂ + 3 / 2O ₂ + H ₂ O → 2FeO (OH) + 3S

[Reaction Formula 2]
2FeO (OH) + 3H ₂ S → FeS + FeS ₂ + 4H ₂ O

  Here, the reaction formula 1 shows a reaction mechanism when iron oxide is sulfided using a sulfurization treatment gas containing a sulfur compound and oxygen, and the reaction formula 2 shows that the iron oxide is formed only with a sulfur compound without oxygen. The reaction mechanism when sulfiding is shown.

  On the other hand, in the method of sulfurizing iron oxide by exposing the iron oxide to the mixed gas of hydrogen sulfide and oxygen according to the present invention, that is, the sulfurizing treatment gas, there is also a method of artificially injecting the hydrogen sulfide and oxygen into the iron oxide. However, considering the economic aspect and the aspect of treating waste gas generated from industrial fields, the transfer route of hydrogen sulfide generated from landfill power plants, oil refineries, manure treatment plants, sewage treatment plants, etc. At the same time that the iron oxide is exposed, air is supplied to the iron oxide exposed to the hydrogen sulfide to remove the hydrogen sulfide by adsorption, thereby treating the hydrogen sulfide generated from the pollution source and at the same time, naturally sulfiding the iron oxide. It is better to use a method of processing.

As described above, the present invention has an effect of providing an adsorbent that removes vapor phase mercury after sulfurating iron oxide to accumulate sulfur.
In addition, the present invention can recycle resources by synthesizing iron oxide using waste generated from industrial sites and manufacturing an adsorbent that removes mercury contained in exhaust gas. There is an effect that pollution can be reduced.

  Hereinafter, the method for producing an adsorbent for removing mercury according to the present invention will be described in more detail. Here, the iron oxide used as the mercury-removing adsorbent according to the present invention may be any ordinary iron oxide, but for easy explanation of the present invention, polysulfuric acid may be used. The adsorbent for removing mercury using iron oxide synthesized from ferric iron is specified and described.

  In order to produce the adsorbent for removing mercury according to the present invention, first, i) polyferric sulfate and water are mixed and stirred to a pH of 1-2 and a concentration of 0.5-1 M of ferric sulfate. Producing an aqueous solution; and ii) by gradually dropping a 1 to 2 M aqueous alkaline solution into the aqueous ferric sulfate solution of step i) to gradually increase the pH of the aqueous ferric sulfate solution, Preparing a suspension; and iii) increasing the suspension of step ii) to about pH 8 and then interrupting the dropping of the aqueous alkaline solution and stirring for about 1 hour until the pH is maintained at about 8. And iv) after completion of step iii), filtering the precipitate using ultrapure water, and v) drying the precipitate of step iv) at a temperature of about 100-150 ° C. for oxidation. And vi) a step of sulfiding the iron oxide of step v).

  Here, the sulfidation treatment in the step vi) is a sulfidation comprising 0.001 to 2% by volume of a sulfur compound, 1 to 50% by volume of oxygen and 48 to 98.999% by volume of a carrier gas based on the total volume of the sulfidation gas. It is to expose iron oxide to the processing gas.

  If necessary, it may further comprise an extrusion step for shaping the form of the mercury-removing adsorbent between step v) and step vi) or after step vi). Depending on the intended use and method of the mercury-removing adsorbent produced in the process of extruding into a ball, pellet or honeycomb, more particularly in step v) above The dried iron oxide is extruded and then sulphided, or after the sulphiding in the step vi) is finished, the mercury removing adsorbent can be finally extruded, preferably the dried oxide After extrusion of iron, it is preferable to sulfidize.

  Any alkaline aqueous solution may be used as long as it is a substance capable of neutralizing the ferric sulfate. Ammonium carbonate, ammonia, sodium hydroxide or a mixture thereof, particularly preferably ammonium bicarbonate, is preferably dissolved in water to have a concentration of 1M.

In drying the precipitate of step v), the drying temperature affects the structure of the iron oxide to be produced. Therefore, when the drying temperature is rapidly increased or dried at a temperature of 150 ° C. or higher. Since the structure of iron oxide is produced from FeO (OH) to Fe ₂ O ₃ , the drying temperature is at least 150 ° C. or less, preferably 100 to 150 ° C., particularly preferably 110 to 120 ° C. at the same time. The drying temperature of the precipitate must be gradually increased from a low temperature, preferably 20 ° C., and then maintained at a high temperature, preferably 100-150 ° C.

  The form of the adsorbent for mercury removal is determined by extrusion of the iron oxide produced according to the present invention. Therefore, the extrusion molding may be any extrusion molding method usually used in the industry, but preferably milled manufactured iron oxide or sulfurized iron oxide. To produce a fine powder, and the produced fine powder is combined with an ordinary organic binder such as methylcellulose, PVA (polyvinyl alcohol), dextrin and a crosslinking agent such as alumina sol or colloidal silica. An adsorbent for removing mercury is produced by mixing with (colloidal silica) and molding with an extruder.

  The adsorbent for removing mercury according to the present invention produced as described above is an adsorbent that adsorbs and removes vapor phase mercury, preferably vapor phase mercury contained in exhaust gas, or a similar pollutant such as heavy metal. Etc. are used for adsorbing and removing.

  Hereinafter, the present invention will be described specifically by way of examples. However, the following examples are for illustrative purposes only and are not intended to limit the scope of the present invention.

<Example 1>
Manufacture of iron oxides 78 mL of polyferric sulfate (Cosmo Chemical, Korea) solution containing 11% Fe ³⁺ ions is mixed with 427 mL of water, and 0.5M (Fe ³⁺ standard) aqueous solution of polyferric sulfate Manufactured.
Then, after maintaining pH of the manufactured polyferric sulfate aqueous solution to 1-2, it stirred at 600-800 rpm for about 60 minutes using the stirrer (CERAMAG MIDI, IKA Works, Italy).

Next, 96 g of ammonium carbonate (manufactured by Doksan Chemical Co., Ltd., Korea) was dissolved in 1000 mL of water to prepare a 1M aqueous alkaline solution as a precipitant, and then dropped into the aqueous ferric sulfate solution.
At this time, a precipitate is generated when the alkaline aqueous solution is dropped, and agglomeration phenomenon of the generated particles occurs. Therefore, the stirrer for stirring the aqueous ferric sulfate solution is strongly at a speed of 320 rpm or more. The mixture was stirred and an aqueous alkaline solution was slowly dropped at a rate of about 0.084 ml / s to suppress the aggregation phenomenon of the generated precipitate.

Thereafter, an alkaline aqueous solution was dropped into the aqueous ferric sulfate solution, and the pH of the aqueous ferric sulfate solution was increased to about 3 to prepare a reddish brown suspension.
Next, the pH of the reddish brown suspension is slowly increased to 8 while dropping the alkaline aqueous solution continuously, and when the pH of the suspension reaches 8, the dropping of the alkaline aqueous solution is interrupted. After confirming the change in pH while continuing stirring for 1 hour or more, stirring of the suspension was interrupted if the pH of the suspension did not change.
Thereafter, in order to remove the anions contained in the suspension, the precipitate is filtered a number of times using ultrapure water, and the filtered precipitate is dried at a temperature of about 110 ° C. to oxidize. 22.5 g of iron was produced.

  XRD (RINT2200, Rigaku, Japan) and BET (ASAP2010, Micrometrics, USA) were measured to measure the physical properties of the manufactured iron oxide, and the results are shown in Table 2 and FIG.

As shown in FIG. 2, the manufactured iron oxide is amorphous with almost no crystallinity, and as a result of BET analysis, the specific surface area of the manufactured iron oxide is 360 to 430 m ² / g, and the pore volume is The pore diameter was 0.24 to 0.46 cm ² / g and the pore diameter was 25 to 45 mm.

<Example 2>
Production of iron oxide 1M alkali using ammonium bicarbonate (NH ₄ HCO ₃ ) (manufactured by Doksan Chemical, Korea) instead of 1M alkaline aqueous solution using ammonium carbonate. An aqueous solution was used.
The results are shown in Table 2 and FIG.

<Example 3>
Production of iron oxide The same procedure as in Example 1 was carried out except that ammonium hydroxide (NH ₄ OH) [manufactured by Doksan Chemical Co., Korea] was used as the precipitating agent instead of 1M alkaline aqueous solution using ammonium carbonate. A 1M aqueous alkaline solution was used.
The results are shown in Table 2 and FIG.

<Example 4>
Production of iron oxide The same method as in Example 1 is used, but instead of a 1M alkaline aqueous solution using ammonium carbonate, a 1M alkaline aqueous solution using sodium hydroxide (NaOH) [manufactured by Doksan Chemical, Korea] is used. did.
The results are shown in Table 2 and FIG.

<Example 5>
Iron oxide sulfidation and removal of hydrogen sulfide A glass reactor having a diameter of 36 mm and a height of 200 mm in which an inlet and an outlet are opposed to each other was manufactured, and then the iron oxide 60 cm ³ manufactured in Example 1 was formed therein. Filled.
Thereafter, hydrogen sulfide gas having a balance of 10% H ₂ S / N ₂ is made 2% of the total flow rate at the inlet of the glass reactor, and the flow rate is 1,000 cm ³ / with air having an oxygen concentration of 3%. An adsorbent for removing mercury was produced by flowing in min and sulfiding iron oxide.

  Thereafter, the hydrogen sulfide concentration of the gas flowing out through the outlet was measured with a detector tube [4LL, Gastech, Japan]. At this time, the time when the concentration of leaked hydrogen sulfide was 10 ppm (TLV value) was taken as the time of destruction. Here, the TLV (Threshold limit value) value is a degree of harmful gas leakage set by ACGIH (American Conference of Governmental industrial Hygienists, Inc.), and indicates a stable degree of harmful gas leaking from the workplace. Means a number. By the above method, the hydrogen sulfide adsorption performance of the synthesized iron oxide can be evaluated.

In addition, after leaking beyond the TLV value, the position of the inlet and outlet is changed, hydrogen sulfide is further injected, the portion of iron oxide that does not undergo sulfidation treatment is reduced, and such a method is repeated. Sulfurized mercury removal adsorbent was produced.
The results are shown in Table 3.

<Example 6>
Iron oxide sulfidation treatment and removal of hydrogen sulfide were carried out in the same manner as in Example 5, but instead of the iron oxide produced in Example 1, the iron oxide produced in Example 2 was used.
The results are shown in Table 3.

<Example 7>
Iron oxide sulfidation and hydrogen sulfide removal The same procedure as in Example 5 was used, but instead of the iron oxide produced in Example 1, the iron oxide produced in Example 3 was used.
The results are shown in Table 3.

<Example 8>
Iron oxide sulfidation and hydrogen sulfide removal The same procedure as in Example 5 was used, but instead of the iron oxide produced in Example 1, the iron oxide produced in Example 4 was used.
The results are shown in Table 3.

<Comparative Example 1>
In the same manner as in Example 5, but without inflow of oxygen-containing air, hydrogen sulfide gas having a balance of 10% H ₂ S / N ₂ was added to the total flow rate at the inlet of the glass reactor. The iron oxide was sulfided by flowing at a flow rate of 1,000 cm ³ / min at a concentration of 1%.
The results are shown in Table 3.

<Comparative Example 2>
The same process as in Comparative Example 1 was used, but instead of the iron oxide produced according to Example 1, the iron oxide produced according to Example 2 was used.
The results are shown in Table 3.

<Comparative Example 3>
The same process as in Comparative Example 1 was used, but instead of the iron oxide produced according to Example 1, the iron oxide produced according to Example 3 was used.
The results are shown in Table 3.

<Comparative Example 4>
The same process as in Comparative Example 1 was used, but instead of the iron oxide produced according to Example 1, the iron oxide produced according to Example 4 was used.
The results are shown in Table 3.

  As shown in Table 3, the iron oxide produced between the polyferric sulfate and ammonium carbonate according to Example 5 is relatively large compared to the iron oxide produced from Examples 6-8. Of hydrogen sulfide can be treated. This is because the iron oxide produced in Example 5 has a large specific surface area, a large pore volume, and a large pore size, so that a large amount of sulfur can be impregnated.

  Moreover, from Table 3, Examples 5 to 8 in which iron oxide was oxidized using a sulfur compound and oxygen mixed gas were comparative examples in which iron oxide was acid-treated only with a sulfur compound without oxygen under the same conditions. 1 It can be seen that a larger amount of hydrogen sulfide is treated than Comparative Example 4.

<Example 9>
Mercury adsorption performance evaluation After an SUS reactor having a diameter of 25 mm and a height of 200 mm with the inlet and outlet facing each other was manufactured, the inside was filled with 20 cm ³ of an adsorbent for mercury removal that was sulfurized in Example 5. did.

Thereafter, liquid mercury is put into a gas reaction tube [glass processed product], and then vapor phase mercury is produced by bubbling in a temperature range of 25 to 28 ° C., and the produced vapor phase mercury is set to a flow rate of 90 cm ³ / min. And flowed into the inlet of the reactor. At this time, using nitrogen as a carrier gas, the total flow rate including mercury flowing into the reactor was maintained at 1000 cm ³ / min, and the concentration thereof is shown in Table 4.
Next, the concentration of mercury flowing out through the outlet of the reactor was measured using a mercury analyzer [VM-3000, mercury instruments analytical technologies, Germany].
The results are shown in Table 4.

<Example 10>
Mercury adsorption In the same manner as in Example 9, the mercury removing adsorbent produced in Example 6 was used in place of the mercury removing adsorbent sulfurized in Example 5.
The results are shown in Table 4.

<Example 11>
Mercury adsorption In the same manner as in Example 9, the mercury removing adsorbent produced in Example 7 was used in place of the mercury removing adsorbent sulfurized in Example 5.
The results are shown in Table 4.

<Example 12>
Mercury adsorption In the same manner as in Example 9, the mercury removing adsorbent produced in Example 8 was used instead of the mercury removing adsorbent sulfurized in Example 5.
The results are shown in Table 4.

<Comparative Example 5>
In the same manner as in Example 9, the mercury removing adsorbent produced in Comparative Example 1 was used instead of the mercury removing adsorbent sulfurized in Example 5.
The results are shown in Table 4.

<Comparative Example 6>
In the same manner as in Example 9, the mercury removing adsorbent produced in Comparative Example 2 was used in place of the mercury removing adsorbent sulfurized in Example 5.
The results are shown in Table 4.

<Comparative Example 7>
In the same manner as in Example 9, the mercury removing adsorbent produced in Comparative Example 3 was used in place of the mercury removing adsorbent sulfurized in Example 5.
The results are shown in Table 4.

<Comparative Example 8>
In the same manner as in Example 9, the mercury removing adsorbent produced in Comparative Example 4 was used instead of the mercury removing adsorbent sulfurized in Example 5.
The results are shown in Table 4.

  As shown in Table 4, it was found that the synthetic iron oxide according to Example 5 used in Example 9 in which a large amount of hydrogen sulfide was adsorbed had high adsorption performance for removing atomic mercury. This indicates that among the synthesized iron oxides, iron oxide synthesized with polyferric sulfate and ammonium carbonate according to Example 1 can treat the largest amount of mercury.

  Moreover, from Table 4, Examples 9 to 12 in which iron oxide was oxidized using a sulfur compound and oxygen mixed gas were comparative examples in which iron oxide was acid-treated only with a sulfur compound without oxygen under the same conditions. 5 It was found to process more vapor phase mercury than Comparative Example 8.

  As described above, those skilled in the art to which the present invention pertains can understand that the present invention can be implemented in other specific forms without changing its technical idea or essential features. Will. Accordingly, it should be understood that the above-described embodiment is merely illustrative in all aspects and not limiting. The scope of the present invention should be construed to include all modifications or variations derived from the meaning and scope of the claims and their equivalents rather than the detailed description.

It is a flowchart which shows the manufacturing method of the adsorption agent for mercury removal which concerns on this invention. It is a figure which shows the XRD measurement result of the iron oxide manufactured by Examples 1-4 of this invention.

Claims (7)

  Iron oxide sulfided with a sulfurizing gas comprising 0.001 to 2% by volume of a sulfur compound, 1 to 50% by volume of oxygen and 48.0 to 98.999% by volume of a carrier gas based on the total volume of the sulfurating gas Contains an adsorbent for mercury removal. The adsorbent for removing mercury according to claim 1, wherein the mercury is Hg ⁰ , HgCl, or HgCl ₂ .   The adsorbent for removing mercury according to claim 1 or 2, wherein the mercury is vapor phase mercury discharged from a power plant, an incinerator, a mercury battery, a dental amalgam or a mercury fluorescent lamp. The iron oxide is selected from the group consisting of FeO, Fe (OH) ₂ , Fe (OH) ₃ , FeO (OH), Fe ₂ O ₃ , and Fe ₃ O _4. The adsorbent for mercury removal described in 1.   Iron oxide is sulfided with a sulfurizing gas comprising 0.001 to 2.0% by volume of a sulfur compound, 1 to 50% by volume of oxygen and 48.0 to 98.999% by volume of a carrier gas, based on the total volume of the sulfurating gas. A method for producing an adsorbent for removing mercury, including treatment.   6. The method for producing an adsorbent for removing mercury according to claim 5, further comprising extruding the iron oxide before sulfiding or after sulfiding.   6. The method for producing an adsorbent for removing mercury according to claim 5, wherein the adsorbent for removing mercury is produced in the form of a ball, a tablet, a pellet or a honeycomb by the extrusion molding.

Images