KR20190000424A - Preparing method of fluoride ion adsorbent using steel slag and adsorb method for fluoride thereof - Google Patents

Abstract

The present invention provides a manufacturing method of a fluid ion adsorbent using a steel slag which comprises the following steps: (a) preparing a steel slag; (b) changing a surface area and neutralizing capacity of the steel slag by an acid treatment of the steel slag; and (c) retrieving the acid treated steel, cleaning and freeze drying. Therefore, the present invention can be useful as a neutralization agent and an adsorbent of a neutralization by-product by using the steel slag which occurs from a by-product and waste in a steel mill.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for preparing fluoride ion adsorbent using steel slag and a fluoride adsorption method using the same,

The present invention relates to a process for producing a fluorine ion adsorbent using steel slag, which can be used as an adsorbent for an acid neutralizing agent and a neutralization by-product by modifying a steel slag.

Drinking water that exceeds the WHO threshold of more than 1.5 mgL ^{- 1} fluoride has been reported in more than 20 countries to cause health problems such as tooth fluoridation and bone fluoridation. The origin of fluoride in contaminated groundwater is derived from natural sources such as fluorite, apatite, mica and amphibolite, and the degree of contamination is increasing by human activities such as hydrogeological scientific conditions and mine development.

In recent years, chemical spillage has become another factor in soil contamination by fluoride ions. In 2012, there are frequent outbreaks of hydrofluoric acid (HF) spills in CITGO CORPUS Chiristi refinery and Marathon's crude refinery facilities in Texas, USA, and there has been a catastrophic hydrogen fluoride spill in South America in 2012, Effluent wastewater containing fluorine ions increased the concentration of fluoride ions that could be dissolved in water in the soil. Fluoride contamination of soils due to fluoride discharge requires the development of remediation agents that can remove fluoride ions from contaminated soils as well as neutralizers in contaminated areas.

On the other hand, the output of steel slag, which is generated as a byproduct and waste in the steelworks, is about 25 million tons in Korea and it is recycled as raw material of cement. Their main constituents, CaO and MgO, have similar components to those of products marketed as acid neutralizing agents.

Therefore, it is very necessary to develop a fluoride ion adsorbent that can adsorb and remove fluorine ions as a neutralizing by-product adsorbent as well as an acid neutralizing agent using steel slag.

Prior art related to this is Korean Patent No. 1137122, a method for producing a catalyst for high temperature desulfurization using steel making slag and a catalyst for desulfurization (Announcement: 2012.04.19).

Korean Patent No. 1137122 (Published on Apr. 19, 2012)

Accordingly, the present invention is to provide a method for utilizing steel slag generated from a large amount of waste as a neutralizing by-product adsorbent through slag surface modification as well as an acidifying agent for harmful compounding materials.

The problems to be solved by the present invention are not limited to the above-mentioned problem (s), and another problem (s) not mentioned can be understood by those skilled in the art from the following description.

In order to solve the above problems, the present invention provides a method of manufacturing a steel slag, comprising the steps of: (a) preparing a steel slag; (b) subjecting the steel slag to an acid treatment to change the surface area and the neutralization capacity of the steel slag; And (c) recovering, washing and lyophilizing the acid-treated steel slag. The present invention also provides a method for manufacturing a fluorine ion adsorbent using steel slag.

Also, in preparing the steel slag, the steel slag may be dried and crushed at 100 to 110 ° C for 20 to 24 hours to form particles having a size of 100 μm or less.

Further, the steel slag may be a wolfram slag or KR slag.

Also, the acid treatment may be acidified using a 1N HCl solution, and the degree of acidification may be 25-100%.

The acid treatment may be carried out at a temperature of 20 to 100 ° C by acidification using a 1N HCl solution.

The washing may also be carried out by vacuum filtration followed by leaching with deionized water three to five times.

The neutralization capacity of the fluorine ion adsorbent using the steel slag may be 6.0 to 13.0 equiv / kg.

Also, the surface area of the KR slag having a surface area of 10 m ² / g may be changed to 20 to 50 m ² / g by the acid treatment.

Also, the surface area of the water-based slag having a surface area of 0.2 m ² / g may be changed to 3 to 9 m ² / g by the acid treatment.

Further, the method may further include the step of adding 1% of sodium hydroxide (NaOH) after the lyophilization step, suspending for 24 hours, and drying at 250 to 300 ° C for 24 hours.

According to another aspect of the present invention, a fluorine ion adsorbent using steel slag is mixed with a fluorine ion-containing soil to adsorb and remove fluorine ions.

The mixing is performed at 20 to 25 캜 at room temperature, and can be adjusted to pH 4.0 using an acidic buffer solution.

According to the present invention, it is possible to utilize steel slag generated from a steel mill in large quantities as by-products and wastes as an adsorbent for neutralization by-products as well as an acid neutralizing agent.

When a steel slag is used, a large amount of an acidifying agent can be produced at a low cost as compared with a commercial neutralizing agent.

In addition, since the fluorine ion adsorbent using steel slag can exhibit a higher neutralizing capacity than that of the commercial acid neutralizing agent, it can be used as various acid neutralizing agents.

In addition, the basic component of steel slag can be used as a chemical functional group capable of removing acid pollutants, and can exhibit a high absorption efficiency particularly for carbon dioxide and nickel.

Also, the surface area and the neutralization capacity can be changed according to the acid treatment. In this case, the fluoride ion, which is a neutralization by-product, can be adsorbed, so that the fluoride ions that can be eluted by the water in the contaminated soil can be very effectively adsorbed and removed .

Through multivariate analysis, it is possible to design a new fluoride ion adsorbent according to the constituent elements of the adsorbent by confirming the adsorption ability of fluoride ions according to the constituent elements in the steel slag.

1 is a process flow chart showing a process sequence of a method for producing a fluorine ion adsorbent using steel slag according to an embodiment of the present invention.
FIG. 2 is a graph showing the acid neutralization capacity of steel slag in a method of producing a fluorine ion adsorbent using steel slag according to an embodiment of the present invention, in comparison with a commercial acidizing agent.
FIG. 3 is a graph showing the change of the surface area according to the acid treatment reaction temperature in the method of producing the fluorine ion adsorbent using the steel slag according to the embodiment of the present invention.
FIG. 4 is a graph showing absorption capacities of carbon dioxide and nickel ions of a fluorine ion adsorbent prepared by the method for producing a fluorine ion adsorbent using a KR slag according to an embodiment of the present invention.
FIG. 5 is a graph showing changes in specific surface area and neutralization capacity of the fluorine ion adsorbent prepared by the process for producing a fluorine ion adsorbent using KR slag according to an embodiment of the present invention, according to an acid-base treatment.
FIG. 6 is a graph showing a multivariate analysis of the fluorine ion adsorbent prepared by the process for producing a fluorine ion adsorbent using KR slag according to an embodiment of the present invention.
7 is a scanning electron microscope (SEM) image of the surface of the fluorine ion adsorbent prepared according to the method of manufacturing a fluorine ion adsorbent using steel slag according to an embodiment of the present invention.
FIG. 8 is a graph showing a change in neutralization capacity according to the specific surface area of a fluorine ion adsorbent prepared by the method for producing a fluorine ion adsorbent using steel slag according to an embodiment of the present invention.
9 is a schematic view showing a process of adsorbing fluorine ions with a fluorine ion adsorbent in a method of adsorbing fluorine ions using a fluorine ion adsorbent using steel slag according to an embodiment of the present invention.
10 is a graph showing a correlation between the surface area of the fluorine ion adsorbent and the Al surface concentration and the fluorine ion removal efficiency in the fluorine ion adsorption method using the fluorine ion adsorbent using the steel slag according to the embodiment of the present invention.
FIG. 11 is a multivariate analysis graph showing the correlation of respective variables in a fluorine ion adsorption method using a fluorine ion adsorbent using steel slag according to an embodiment of the present invention. FIG.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the present invention and the manner of achieving it will become apparent with reference to the embodiments described in detail below with reference to the accompanying drawings.

The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. To fully disclose the scope of the invention to those skilled in the art, and the invention is only defined by the scope of the claims.

In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail.

The present inventors considered the physical properties of each or all of them in order to increase fluorine ion removal efficiency while manufacturing high performance fluorine ion adsorbents with various geomaterials. It was confirmed that the binding sites of fluoride ions, which are determined by the concentration of the surface to which the fluorine ions can be bound and the area of the bondable sites, can be controlled by the variables.

The obstacles associated with identifying important factors that can regulate the removal efficiency of fluoride ions in heterogeneous multi-component materials are due to a variety of independent variables, and because of their interrelationships between the variables, affect the fluoride ion adsorption mechanism as a whole We tried to solve the problem by using multivariate analysis method such as Principal component analysis (PCA).

In particular, PCA is a multivariate analysis method that can reduce variables introduced into several key factors contributing to the change in data recruitment. When the physical properties can not be confirmed by conventional analytical methods, the main elements are derived and used for analysis.

Therefore, we analyzed the surface properties of PCA and confirmed the ability to remove fluoride ions from 11 different types of perceptive materials. The complexity of various parameters was reduced to several important parameters related to physicochemical properties, And the present invention has been completed through a method of changing the above.

In the present invention, steel slag is defined as blast furnace slag and steel making slag, and is defined as brass slag belonging to blast furnace slag and KR slag belonging to steelmaking slag (hereinafter referred to as KR slag).

1 is a process flow chart showing a process sequence of a method for producing a fluorine ion adsorbent using steel slag according to an embodiment of the present invention.

Referring to FIG. 1, a method for producing a fluorine ion adsorbent using steel slag according to the present invention comprises the steps of: (a) preparing a steel slag; (b) subjecting the steel slag to an acid treatment to change the surface area and the neutralization capacity of the steel slag; And (c) recovering, washing and lyophilizing the acid-treated steel slag.

In preparing the steel slag, the steel slag may be dried and crushed at a temperature of 100 to 110 ° C. for 20 to 24 hours to form particles having a size of 100 μm or less.

In this range, moisture and organic impurities in the steel slag can be removed, and the pulverization can be effectively performed.

In addition, when the particle size is adjusted to be 100 μm or less, the acid and the reaction can proceed efficiently in the acid treatment.

The steel slag may be wood slag or KR slag.

In the case of acid-neutralizing agents based on neutralization capacity, it is possible to select both brick slag and KR slag. However, in the case of adsorbing and removing fluorine ion, which is a by-product of neutralization, when the KR slag is selected and acid treated, the specific surface area and neutralization capacity are further increased .

The acid treatment may be acidified using a 1N HCl solution, with an acidification degree of 25-100%.

The acidification degree of 100% means the result of reaction with a 1N HCl solution corresponding to the neutralization capacity of the untreated waterglass slag and the KR slag.

In the acidification range, some of the basic components present on the surface of the steel slag may be partially melted to form a morphology, and the specific surface area may be increased.

The acid treatment may be carried out at a temperature of 20 to 100 ° C by acidification using a 1N HCl solution.

The specific surface area tended to increase with increasing acid treatment temperature.

The washing may be carried out by vacuum filtration followed by leaching with deionized water three to five times.

In the case of repeatedly washing the steel slag with deionized water, the basic component is melted and the neutralization performance may be reduced. Therefore, it is very desirable to wash the steel slag within the above range.

The neutralization capacity of the fluorine ion adsorbent using the prepared steel slag may be 6.0 to 13.0 equiv / kg.

Since the neutralization capacity shows equal or superior neutralizing capacity to the same mass as compared with the commercial acidizing agent, the fluorine ion adsorbent using the steel slag can be used as a highly effective acidizing agent.

By the acid treatment, the surface area of KR slag having a specific surface area of 10 m ² / g of KR slag can be changed to 20 to 50 m ² / g.

This acid treatment by a specific surface area 0.2 m ² / g surface area of the granulated slag can vary from 3 to 9 m ² / g.

In the case of brick slag, the change of specific surface area is not significant by acid treatment, but the variation of KR slag is very large and acid treatment is very effective.

On the other hand, after the lyophilization step, addition of 1% sodium hydroxide (NaOH) may be carried out for 24 hours, followed by drying at 250 to 300 ° C for 24 hours.

When the basic component is reinforced in the above range, the absorption ability of carbon dioxide and nickel can be greatly increased.

The basic component of steel slag can be used as a chemical functional group to remove acidic pollutants. Especially, when basic components are reinforced, the absorption efficiency of carbon dioxide can be increased as much as the commercial amine-based carbon dioxide absorbent.

In particular, since the basic component of KR slag can be reinforced to greatly increase the adsorption capacity of nickel, it can be used as a water treatment agent.

According to another aspect of the present invention, there is provided a fluorine ion adsorption method using a fluorine ion adsorbent for adsorbing and removing fluorine ions by mixing the fluorine ion adsorbent produced through the above production method with a fluorine ion-containing soil.

The mixing is performed at 20 to 25 캜 at room temperature, and can be adjusted to pH 4.0 using an acidic buffer solution.

At this time, the acidic buffer solution may be a citric acid solution.

Since the adsorption of fluorine ions can be performed using the fluorine ion adsorbent in the temperature range described above, it is possible to effectively adsorb the fluorine ions that can be eluted from the soil.

Hereinafter, the present invention will be described in more detail with reference to the following examples. However, the scope of the present invention is not limited to the following examples.

< Example  1> Preparation of fluorine ion adsorbent

Two types of slag were prepared. Grain type wolfram slag and Kambara reactor desulfurization slag (KR slag) were obtained from POSCO, respectively.

Carbide slag was discharged from the blast furnace, which is rapidly vitrified through rapid cooling of the molten minerals, mainly composed of CaO, SiO ₂ , and Al ₂ O ₃ .

The KR slag is discharged from the desulfurization process before the molten iron is heat treated and consists of CaO, SiO ₂ , and FeO.

Each slag was dried and crushed in a convection oven at 110 ° C for 24 hours in a convection oven before acid treatment, and sieved in a 100 μm sieve.

On the other hand, in order to confirm the neutralization capacity of the water slag and the KR slag, the method of Experimental Example 1 described below was carried out.

The amount of 1 N HCl solution corresponding to 10 g of KR slag, 100% neutralization capacity of water slag is 100 mL and 40 mL.

The acid treatment degree of the slag reacted with the 1N HCl solution corresponding to the neutralization capacity is defined as 100% and the acid treatment degree of the slag reacted with the 1N HCl solution corresponding to 25% and 50% Are defined as 25% and 50%, respectively.

The slag was placed in the same amount of 1N HCl solution as above and heated at 100 &lt; 0 &gt; C for 4 hours to acid treatment. Thereafter, the reaction mixture was cooled to room temperature.

The acid treated slag was filtered with vacuum to remove water and then washed with deionized water to remove residual HCl. The remaining particles in the filtrate were freeze-dried for 3 days.

< Example  2> CO ₂ And Ni ^{2 +}  Absorption experiment

The KR slag produced according to Example 1 under argon was preheated by heating at 200 ° C for 1 hour.

The CO ₂ uptake was measured by a temperature-programmed reaction (TPR) analysis method.

CO ₂ absorption amount of slag is defined as the weight of CO ₂ (g) is a 1 kg slag absorption.

100 mg of KR slag was added to 40 mL phosphoric acid buffer containing 1 ppm Ni ^{2 +} and mixed at room temperature for 24 hours.

The filtered solution was analyzed by ICP-AES using a 0.45 μm PTFE syringe filter.

< Example  3> Adsorption of fluorine ions

To 40 mL of borosilicate glass vial, 100 mg of steel slag or crust material and 40 mL of 0.1 N NaF were added and repeated three times to confirm the ability to remove fluoride ions from 11 crust materials including steel slag.

The perceptible material includes steel slag modified by partial acid treatment, including sand (hereinafter referred to as 'SND') and commercial neutralizing agent Neutrasorb (hereinafter referred to as 'NSB') and Spill-A .

Fluoride ion adsorption experiment was carried out assuming a place containing a very high concentration of fluoride ions while being acidic by influx of wastewater generated by the disinfection work of hydrofluoric acid (HF).

The fluoride ion solution was adjusted to pH 4.0 using a citric acid buffer solution at room temperature of 20 to 25 ° C.

As a result of monitoring the reaction progress of the selected crust material and 0.1 N NaF over time, the removal rate of fluorine was remarkably decreased after 2 hours, so 4 hours was set as the reaction end point.

The vials containing the crust material and NaF aqueous solution were placed in a horizontal shaker and mixed constantly for 4 hours at 200 rpm.

After 4 hours of mixing, the aliquots of the supernatant were filtered through a 25 mm PTFE membrane (Whatman GD / X, 0.45 μm) syringe filter. The fluoride concentration of the filtrate was quantitatively analyzed by ion chromatography (IC).

< Experimental Example  1> Slag  Neutralization capacity evaluation

In the case of spraying large amounts of harmful substances in the case of acid spraying materials, a large amount of sprays should be sprayed.

The possibility of using neutralizer in various crust materials was evaluated.

The price of steel slag (weight / kg) per unit weight of steel slag is 1/2000 of that of commercial neutralizing agent, and that of steel slag is the same as that of commercial neutralizing agent Neutrasorb (hereinafter 'NSB') and Spill- Because it is 1/450 price, it was very favorable for mass production and use.

First, the components of the crustal material were analyzed by X-ray diffraction spectra (XRF).

Component (* alkaline component) wt% KR slag Chopped slag  SPX NSB * Na ₂ CO ₃ 2.4 2.4 7.3 35.9 * MgO 1.3 2.6 39.2 4.3 Al ₂ O ₃ 3.3 9.4 7.2 1.5 SiO ₂ 6.9 21.3 29.8 2.2 * CaO 74.6 60.6 11.6 55.6 Fe 8.1 1.3 3.0 0.3

The analysis of the main components _{CaO, SiO 2, Al 2 O} 3, MgO, Na 2 CO 3 , The steel slag had a similar composition to that of the commercial acidifying agent. In particular, the alkali slag and the slag containing the high contents of NSB, KR slag, wolfram slag and SPX were effective in neutralization reaction Respectively.

When the neutralization capacity (equiv / kg) is defined as the amount (equiv) of the acidic solution necessary for the neutralization agent (1 kg) to reach the neutralization point (pH 7), the neutralization capacity / unit cost (equiv / A measure of cost efficiency can also be utilized.

In order to test the neutralization capacity of the neutralization control agent of particle type, the American National Standard Test Association STP19564S method was modified and used.

Each slag was dried and crushed in a convection oven at 110 ° C for 24 hours in a convection oven before neutralization, and sieved in a 100-m sieve.

2 g of the sample was placed in a 250 mL Erlenmeyer flask and 20 mL of deionized water was added. 1N HCl (aq) was added to the resulting slurry while stirring until the pH of the solution became 7 or less.

Deionized water was added to make the volume of the solution 125 mL and the top of the flask was covered with a watch glass.

The flask was heated until boiling and then cooled until it reached room temperature.

The pH value was measured by taking the supernatant generated during the test. The pH value was defined as?, and the neutralization capacity was determined by the following equation (1).

The above experiment was carried out three times and the average value of the neutralization capacity calculated was defined as the neutralization capacity of the slag.

[Equation 1]

[Supernatant OH ^- concentration] = 10 ^{- (14 -?)} (When? Is more than 7)

= -10 ^{- ?} (When? Is less than 7)

FIG. 2 is a graph showing acid neutralization capacity of steel slag in a method of producing a fluorine ion adsorbent using steel slag according to an embodiment of the present invention.

2, the neutralization capacity of the sample derived from the steel slag was evaluated. As a result, it was confirmed that the neutralizing capacity of the KR slag was higher than that of the commercial acid neutralizing agent.

FIG. 3 is a graph showing the change of the surface area according to the acid treatment reaction temperature in the method of producing the fluorine ion adsorbent using the steel slag according to the embodiment of the present invention. Referring to FIG. 3, The specific surface area was greatly increased.

The specific surface area tended to increase with increasing acid treatment temperature.

< Experimental Example  2> CO ₂  And Ni ^{2 +}  absorption

The basic component of steel slag can be used as a chemical functional group to remove various acid pollutants. For example, we tested the CO ₂ absorption performance of KR slag with high neutralization capacity. The CO ₂ absorption performance was analyzed by a temperature programmed reaction (TPR) method and the sample pretreated at 200 for 1 hour in the Ar environment was expressed as the total amount of CO ₂ absorbed while heating to 600.

FIG. 4 is a graph showing absorption capacities of carbon dioxide and nickel ions of a fluorine ion adsorbent prepared by a method of producing a fluorine ion adsorbent using steel slag according to an embodiment of the present invention.

Referring to FIG. 4, the CO ₂ absorption performance of the KR slag was positively correlated with the basic component content.

The more basic components of Na, Ca, Mg and Ni ^{2 +} CO ₂ removal efficiency is increased, it was confirmed that CO ₂ removal efficiency is more sensitive to the base content than Ni ^{2 +} removal efficiency.

In the case of the untreated KR 0% slag, the absorption efficiency (about 80 g CO ₂ / kg) of the amine-based material with high CO ₂ absorption efficiency was shown to be a cost-effective CO ₂ absorbent.

The effects of KR slag on specific surface area and neutralization capacity were evaluated according to acid treatment degree and base treatment degree.

FIG. 5 is a graph showing changes in specific surface area and neutralization capacity of the fluorine ion adsorbent prepared by the process for producing a fluorine ion adsorbent using KR slag according to an embodiment of the present invention, according to an acid-base treatment.

Referring to FIG. 5, the specific surface area of KR slag was increased with increasing acid treatment degree up to 50%, and then decreased.

Also, it was confirmed that the increase of surface area did not affect the KR slag neutralization capacity, and the surface area was decreased but the neutralization capacity was increased when treated with NaOH.

On the other hand, we tried to confirm the correlation between the specific surface area, basic content and neutralization capacity by Principal Component Analysis (PCA).

FIG. 6 is a graph showing a multivariate analysis of the fluorine ion adsorbent produced by the method of producing a fluorine ion adsorbent using steel slag according to an embodiment of the present invention.

Referring to FIG. 6, the data required for the analysis are the basic content, neutralization capacity, specific surface area, and CO ₂ content of the samples treated with 25%, 50%, and 100% acid based on the KR slag value, The absorption efficiency values were analyzed.

In the KR slag, the basic content (PC1) was the most significant factor for the acid content and the CO ₂ absorption efficiency by acid base treatment, and the neutralization capacity was correlated with both the basic content and the specific surface area.

<Experimental Example 3> Property change by acid treatment

The surface of wolfram slag and KR slag was examined by scanning electron microscope according to the degree of acid treatment.

7 is a scanning electron microscope (SEM) image of the surface of the fluorine ion adsorbent prepared according to the method of manufacturing a fluorine ion adsorbent using steel slag according to an embodiment of the present invention.

Referring to FIG. 7, it was confirmed that the surface of the steel slag was roughened and the surface area thereof was increased, and a unique projection structure was formed in the KR slag.

The Brunauer-Emmett-Teller (BET) analysis of the perceptual material was analyzed with ASAP 2420 (Micrometrics®).

Samples were dried under vacuum at 200 ℃ for 4 hours prior to analysis. The specific surface area and the volume of pores were calculated by the nitrogen adsorption curve.

Slag type Degree of acidification 0% (not processed) 25% 50% 100% Chopped slag 0.23 3.97 8.26 7.76 KR slag 10.35 22.11 41.35 25.73

Table 2 shows the specific surface area according to the degree of acid treatment.

The surface area was increased as the degree of acidification increased.

On the other hand, the neutralization capacity of the surface - modified steel slag was measured in order to confirm the influence of the surface increase of the steel slag on the neutralization capacity.

FIG. 8 is a graph showing a change in neutralization capacity according to the specific surface area of a fluorine ion adsorbent prepared by the method for producing a fluorine ion adsorbent using steel slag according to an embodiment of the present invention.

Referring to FIG. 8, in the case of KR slag, the neutralization capacity was maintained constant irrespective of the acid treatment degree and the surface area change, and in the case of the wastewater slag, the neutralization capacity decreased as the acid treatment degree increased.

It was concluded that the neutralization capacity also showed a significant correlation with the content of base components rather than the change of reaction rate with changes in surface area.

< Experimental Example  4> Evaluation of fluorine ion removal

It was confirmed that the modified steel slag could adsorb and remove fluoride ion, which is a by-product of neutralization.

9 is a schematic view showing a process of adsorbing fluorine ions with a fluorine ion adsorbent in a method of adsorbing fluorine ions using a fluorine ion adsorbent using steel slag according to an embodiment of the present invention.

Referring to FIG. 9, the reaction of immobilizing fluorine ions on the surface of the crust material containing steel slag and the result thereof are illustrated.

The crustal materials used in the experiment were sand slab (GB slag) and 11 KR slag treated with 25%, 50% and 100% acid treated NSB and SPX, respectively.

The results of BET surface area analysis, XPS surface analysis, EDS element imaging analysis and fluorine ion removal efficiency of eleven kinds of crust materials were considered to be correlated with chemical properties such as surface area and element content of the controlling agent. IC analysis results).

X-ray photoelectron spectroscopy (XPS) analysis was performed to analyze the composition of the surface layer of 5 nm before and after exposure to sodium fluoride (NaF) solution, and F, Al, C, Ca, O , And Si were analyzed using a Quantax 200 Energy Dispersive x-ray spectrometer (Bruker, Germany) equipped with a silicon drift detector.

The energy resolution was less than 127 eV and the peak shift was less than 5 eV.

F, Al, C, Ca, O, and Si dispersed images were obtained from each sample. The numerical value of the outgoing signal intensity at each pixel was extracted using the MATLAB imread and rgb2gray functions.

The two-dimensional matrix resulting from the rgb2gray function was used for the pixel-by-pixel analysis of gray scale signal intensity derived from F and Al, C, Ca, O, or Si EDS mapping images.

10 is a graph showing a correlation between the surface area of the fluorine ion adsorbent and the Al surface concentration and the fluorine ion removal efficiency in the fluorine ion adsorption method using the fluorine ion adsorbent using the steel slag according to the embodiment of the present invention.

Here, (a) shows the fluorine ion removal efficiency according to the change of the surface area, and (b) shows the ion removal efficiency according to the Al content.

FIG. 10 shows the relationship between the BET surface area and the Al surface concentration, which are most closely related to the fluorine ion removal efficiency among the examined factors.

This method shows a correlation with one independent variable related to the fluoride removal efficiency. However, in order to understand the correlation between the factors when multiple independent variables affect the reaction simultaneously, multivariate analysis methods such as PCA are needed Do.

In PCA, a method of chemometric analysis, the input data were determined by the removal efficiency, surface area and compositional components (atom% of C, O, Si, Al, Ca) of fluorine ions.

PCA was performed to determine which of the properties of the perceptual material and the properties of the perceptual material, which are most closely related to the fluorine ion removal efficiency, are explained by the main variables.

The most significant variables, PC1 and PC2, were determined and contributed 58% and 27% of total variance, respectively.

FIG. 11 is a multivariate analysis graph showing the correlation of respective variables in a fluorine ion adsorption method using a fluorine ion adsorbent using steel slag according to an embodiment of the present invention. FIG.

Here, (a) shows the values of PC1 and PC2 according to each variance and shows the correlation between the factors. The two groups of variables were distinguished based on the approximation of PC1 and PC2.

The input values were a combination of orthogonal virtual vectors with respect to fluorine ion removal efficiency and fluorine ion removal efficiency.

The dependence of the respective values on the fluorine ion removal efficiency can be deduced from the inner product of fluorine ion removal efficiency. The most closely related to the fluorine ion removal efficiency was surface area.

A positive correlation between the fluorine ion removal efficiency and the surface area is well shown in Fig. 10 (a).

In contrast, the other variables, Ca, C, O, Al and Si, are orthogonal to the fluorine ion removal efficiency, indicating that the composition of the surface of the perceptual material is not a major factor in fluorine removal efficiency.

The opposite orientation between the constituents of the crustal material compensated for the low content of calcium cabnate, indicating a relatively high content of aluminosilicate.

FIG. 11 (b) shows clusters distinguished corresponding to GB slag and KR slag.

The remainder showed NSB, SND and SPX among the crust materials.

The values of GB slag and KR slag were placed close to the PC1 axis, and their PC1 values were clustered together.

The above results confirm that the composition of the slag is the most distinctive feature than the fluorine ion removal efficiency or surface area. PC1 values for GB slag and KR slag were relatively rich in alumino silicate and calcium carbonate composition, respectively.

Referring to FIG. 10 (b), KR slag and SPX were found to be able to more effectively remove fluorine ions than materials with larger amounts of Al, Si, or O, such as GB slag or SND.

The results are believed to be due to the large surface area of KR slag and SPX and have been shown to promote effective adsorption of fluoride ions.

The steeper slope of the regression line in KR slag and SPX indicated that smaller amounts of Al and Si atoms were involved in the fixation of KR slag and SPX fluoride ion than in GB slag and NSB.

This indicates that Al or Si in the KR slag has a higher affinity for the fluorine ion, whereas GB slag and NSB, on the contrary, utilize more Al or Si atoms to remove fluorine ions as KR slag .

As a result of multivariate analysis, it can be effectively removed by the aluminosilicate material having a surface area in the acidic condition of pH 4 in the acidic condition of pH 4, and it can be effectively removed by the modification of the steel slag, Ion adsorbent.

Therefore, the present invention confirms the removal efficiency of fluorine ions dissolved in water under acidic conditions according to the chemical properties of the perceptible substances.

The removal of fluoride ions from 11 kinds of crustal materials consisting of commercial or modified slag was confirmed.

XPS analysis confirmed that the fluorine ion was successfully immobilized, and the surface area and the fluorine ion removal efficiency were correlated with each other. Positive correlations were not applied to the part of the perceptual material, suggesting that other factors are important for the removal efficiency of fluoride ions.

On the other hand, multivariate analysis (PCA) showed that the surface area was most related to fluorine ion removal efficiency and that all elements were related to the removal efficiency of fluorine ions finely. Microscopic analysis using EDS technique confirmed that Al, Si, or O is an important parameter for the removal of fluoride ions after the fluorine ion adsorption reaction.

 The above results show important information affecting the fluorine ion adsorption efficiency through understanding of the main chemical properties of the multi-component crustacean material and suggested the criteria for producing a high performance fluorine ion scavenger with a crust material under acidic conditions .

As a result, the aluminosilicate-rich crustal material is advantageous for use as a fluorine adsorbent because of its large surface area.

Although the present invention has been described with reference to specific embodiments of the method for producing a fluorine ion adsorbent using steel slag and the fluorine ion adsorption method using the same, Do.

Therefore, the scope of the present invention should not be construed as being limited to the embodiments described, but should be determined by equivalents to the appended claims, as well as the following claims.

It is to be understood that the foregoing embodiments are illustrative and not restrictive in all respects and that the scope of the present invention is indicated by the appended claims rather than the foregoing description, It is intended that all changes and modifications derived from the equivalent concept be included within the scope of the present invention.

Claims (11)

(a) preparing a steel slag;
(b) subjecting the steel slag to an acid treatment to change the surface area and the neutralization capacity of the steel slag; And
(c) recovering, washing, and lyophilizing the acid-treated steel slag. The method according to claim 1,
In preparing the steel slag
Wherein the steel slag is dried and pulverized at 100 to 110 DEG C for 20 to 24 hours to form particles so that the particle size is less than 100 mu m.
The method according to claim 1,
The steel slag
Wherein the slag is a water slag or a KR slag.
The method according to claim 1,
The acid treatment
1N HCl solution, and the degree of acidification is 25 to 100% of the neutralizing capacity. The method for producing a fluorine ion adsorbent using the steel slag according to claim 1,
The method according to claim 1,
The acid treatment
1N &lt; / RTI &gt; HCl solution at 20 to &lt; RTI ID = 0.0 &gt; 100 C. &lt; / RTI &gt;
The method according to claim 1,
The washing
Followed by leaching with deionized water for 3 to 5 times, followed by filtration under reduced pressure to obtain a fluorine ion adsorbent.
The method according to claim 1,
The neutralization capacity of the fluorine ion adsorbent using the steel slag is
6. The method for producing fluorine ion adsorbent using steel slag according to claim 1,
The method according to claim 1,
The specific surface area of the KR slag having a specific surface area of 10 m ² / g is changed to 20 to 50 m ² / g by the acid treatment and the specific surface area of the water slag having a specific surface area of 0.2 m ² / g is 3 to 9 m ² / g. &Lt; RTI ID = 0.0 &gt; 8. &lt; / RTI &gt;

The method according to claim 1,
Further comprising the step of adding 1% of sodium hydroxide (NaOH) after the lyophilization step for 24 hours and drying at 250 to 300 ° C for 24 hours.
A fluorine ion adsorbing method using a fluorine ion adsorbent produced by the method of any one of claims 1 to 8, wherein the fluorine ion adsorbent is mixed with the fluorine ion-containing soil to adsorb and remove the fluorine ion.
11. The method of claim 10,
Wherein the mixing is performed at a temperature of 20 to 25 캜 at room temperature, and the pH is adjusted to 4.0 using an acidic buffer solution.

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