KR20150075145A - Heavy metal absorbent comprising acid pretreated red mud and method for removing heavy metal using the same - Google Patents

Abstract

The present invention relates to a heavy metal adsorption removing agent including red mud pre-treated with an acid and a method for removing heavy metal from fresh water or sea water using the same wherein the red mud, which is an industrial byproduct, is pre-treated with an acid solution and used as a heavy metal adsorption removing agent, thereby having an outstanding effect of removing heavy metal compared with an existing adsorption agent like steelmaking slag, montmorillonite and illite and being used for removing heavy metal from fresh water or sea water.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heavy metal adsorption eliminator including red mud which is pretreated with an acid and a method for removing heavy metals from fresh water or seawater using the same.

The present invention relates to a heavy metal adsorption eliminator containing red mud which has been pretreated with an acid and a method for removing heavy metals in fresh water or seawater using the same.

The industrial wastewater generated by the rapid development of the first-class industry has been released to a large extent beyond the midnight effect of nature, and thus the water pollution is serious. Especially, leachate and mine drainage from contamination and abandonment of farmland and rivers adjacent to abandoned mines cause continuous pollution of surrounding soil and water environment by the process of rainfall. Water Environment and Soil Contaminated water caused by environmental pollution eventually flows into the ocean and increases pollution in coastal waters. Most of the industrial byproducts such as inland sludge have been treated by marine dumping, which is another major cause of marine pollution. The heavy metals generated from these pollutants are not easily decomposed, and they are concentrated in living organisms. Therefore, much effort is required to purify the marine polluted sediments. In particular, chromium (Cr) in heavy metals is generated by various industrial processes and production activities such as leather, cooling water, and plating, and is introduced into the natural environment and causes soil, groundwater and river pollution.

Chromium (Cr) is classified as a heavy metal that affects the ecosystem in the US Environmental Protection Agency (EPA) and the Agency for Toxic Substances and Disease Registry. It is classified into arsenic, cadmium, cobalt, It is a heavy metal that is managed with concentration. Chromium (Cr) exists in two forms in the presence of various oxidation states, but generally a trivalent (Cr ^{+ 3)} and 6 (Cr ^{+ 6)} depending on the pH and the redox state. Trivalent chromium (Cr ^{3 +} ) is relatively insoluble and exists as a trace element, but hexavalent chromium (Cr ^{6 +} ) exhibits high mobility and bio-toxicity and has a profound effect on human skin, liver, kidneys and respiratory tract . It is reported that hexavalent chromium (Cr ^{6 +} ) induces mutation and cancer, and it is one of the substances which is difficult to treat because it is easy to move in the water system.

Chromium (Cr) can be removed by a conventional heavy metal ion removal method in aquatic environments. Examples of the heavy metal removal method include chemical coagulation sedimentation, evaporation, reverse osmosis, liquid film, oxidation / reduction, ion exchange, . These methods have advantages of recovering heavy metals and are used industrially, but they are expensive and have a large energy consumption. On the other hand, removal of heavy metal adsorption using functional natural minerals and industrial byproducts is economically inexpensive, requires less energy, and is easier to maintain.

Therefore, these heavy metals adsorbing adsorbents are mainly used as covering materials for purification of a very wide range of marine contaminated sediments and soil remediation. As a representative heavy metal adsorbing material, natural minerals such as zeolite, bentonite, apatite and limestone, and industrial byproducts such as fly ash, waste sludge, oyster hull and red mud were mainly used. However, Adsorbent, and the study on seawater environment under various environmental conditions is insufficient.

A problem to be solved by the present invention is to provide a heavy metal adsorption eliminator and a method for producing the same.

Another object of the present invention is to provide a method for removing heavy metals contained in seawater fresh water using the heavy metal adsorption eliminator.

According to an exemplary aspect of the present invention, there is provided a heavy metal adsorption eliminator comprising red mud that has been pretreated with an aqueous acid solution having an oxonium ion concentration of 1.5-3.0 M.

According to another exemplary aspect of the present invention, there is provided a method for preparing a water-soluble polymer, comprising the steps of: (1) adding red mud to an aqueous acid solution having an oxonium ion concentration of 1.5-3.0 M and stirring;

(2) washing the red mud which has been pretreated with the acid obtained in the step (1) with distilled water, and drying the washed red mud.

According to another exemplary aspect of the present invention, there is provided a method for removing heavy metals in water, comprising the step of putting the heavy metal adsorption eliminator into seawater or fresh water to remove heavy metals by an adsorption reaction.

According to various embodiments of the present invention, since red mud as an industrial by-product is pretreated with an aqueous acid solution to be used as a heavy metal adsorption eliminator, heavy metal removal rate is much higher than that of an adsorbent such as steelmaking slag, montmorillonite, An effect that can be usefully used for removing heavy metals in the seawater environment can be achieved.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a graph showing the removal rate of hexavalent chromium ions for an adsorbent type according to an embodiment of the present invention. FIG.
2 is a graph showing the equilibrium adsorption experiment results of red mud pretreated with an acid according to an embodiment of the present invention.
3 is a graph showing the adsorption amount per unit mass and the final pH of the red mud pretreated with an acid according to an embodiment of the present invention.
4 is a graph showing the amount of adsorbed per unit mass and the removal rate of heavy metals with respect to the content of red mud pretreated with an acid according to an embodiment of the present invention.
FIG. 5 is a graph showing the adsorption amount per unit mass and the final pH of a mixture of red rust pretreated with an acid and a conventional adsorbent according to an embodiment of the present invention.
6 is a graph showing adsorption amounts per unit mass of distilled water and sea water environment of red mud pretreated with an acid according to an embodiment of the present invention.

Hereinafter, various aspects and various embodiments of the present invention will be described in more detail.

According to one aspect of the present invention, there is disclosed a heavy metal adsorption eliminator comprising red mud that has been pretreated with an aqueous acid solution having an ion concentration of 1.5-3.0 M of an oxonium (H ₃ O ⁺ ) ion.

As used herein, the term "oxonium ion concentration" refers to a concentration of an oxonium ion present as H ₃ O ⁺ in an aqueous acid solution, in which one molecule of hydrogen ions is coordinated with water in an aqueous acid solution Concentration. In the present invention, it can be defined as a measure indicating the degree of acidity of the aqueous acid solution.

Generally, the degree of acidity is represented by pH, as shown in the following formula (1). To further clarify the present invention, the concentration of oxonium ions for determining the pH is used as a measure of the degree of acidity.

[Reaction Scheme 1]

H ₂ O → H ₃ O ⁺ + OH ^-

On the other hand, according to one embodiment of the present invention, when red mud that is pretreated with an aqueous acid solution having an oxonium ion concentration of less than 1.5 M in red mud pretreated with the acid aqueous solution is used, the heavy metal adsorption rate may be lowered, In case of using red mud pretreated with an aqueous acid solution having a concentration of more than 3.0 M, the pH of the red mud may increase, which may cause secondary contamination in water.

In one embodiment of the present invention, the heavy metal adsorption eliminator is added in an amount of 4-20 w / v% based on 100 ppm of heavy metals.

According to one embodiment of the present invention, when the heavy metal adsorption eliminator is added in an amount of less than 4 w / v% based on 100 ppm of the heavy metal, there may be a problem that the removal rate of the heavy metal is lowered, There is a problem that the adsorption amount per unit mass is rather reduced without increasing the removal rate of the heavy metal.

In another embodiment of the present invention, the heavy metal adsorption eliminator has a heavy metal adsorption amount of 1-2 mg / g.

In another embodiment of the present invention, the heavy metal adsorption eliminator has an average particle size of 60-150 mu m.

According to one embodiment of the present invention, when the average particle diameter of the heavy metal adsorption eliminator is less than 60 탆, there may be a problem of suspended in water, and when it is more than 150 탆, there may be a problem of decreasing the adsorption rate.

In another embodiment of the present invention, the acid aqueous solution is one or more acid aqueous solutions selected from hydrochloric acid, nitric acid, sulfuric acid, and acetic acid.

In another embodiment of the present invention, the heavy metal is at least one selected from the group consisting of chromium, arsenic, selenium, molybdenum, and vanadium, and the heavy metal is preferably hexavalent chromium ion .

In general, prior art Cr (VI), As (V ), heavy metals such as Se (VI), Mo (VI ), V (V) Cr is in an aqueous solution _{^{4 2 -, HAsO 4 2-,}} SeO 4 2 -, MoO ₄ ^{2 -} , HVO ₄ ^{2 -} , and H ₂ VO ₄ ^- , and these anions can be adsorbed by forming Al ³⁺ , Fe ^{3 +} and outer-sphere compounds of red mud, And particularly excellent adsorption performance of hexavalent chromium.

In another embodiment of the present invention, the heavy metal adsorption eliminator is for adsorbing heavy metals in seawater or fresh water.

According to another aspect of the present invention,

(1) adding red mud to an aqueous acid solution having an ion concentration of 1.5-3.0 M of oxonium (H ₃ O ⁺ ) ion and stirring;

(2) A method for producing the heavy metal adsorption eliminator, which comprises washing the red mud which has been pretreated with the acid obtained in the step (1) with distilled water, followed by drying.

In one embodiment of the present invention, the red mud is added in an amount of 1 to 50 parts by weight based on 100 parts by weight of the aqueous acid solution in the step (1).

According to an embodiment of the present invention, it is preferable that the red mud is added to an excess amount of the acid aqueous solution so that the red mud can be treated with the acid evenly. More preferably, And most preferably, 5 to 20 parts by weight of red mud may be added to 100 parts by weight of the aqueous acid solution.

In one embodiment of the present invention, in the step (1), the acid aqueous solution is one or more acid aqueous solutions selected from hydrochloric acid, nitric acid, sulfuric acid and acetic acid.

In another embodiment of the present invention, the drying in the step (2) is performed at a temperature of 80-150 ° C.

According to still another aspect of the present invention, there is provided a method for removing heavy metals in water, comprising the step of putting the heavy metal adsorption eliminator into seawater or fresh water to remove heavy metals by an adsorption reaction.

Heavy metals, such as conventional Cr (VI), As (V ), Se (VI), Mo (VI), V (V) is Cr ² ₄ in an aqueous solution _{^{-, HAsO 4 2 -, SeO}} 4 2-, MoO 4 2 ^- , HVO ₄ ^{2 -} , and H ₂ VO ₄ ^- . When the pH is high, a competitive relationship with OH- is formed, so that the removal rate of heavy metals may be lowered. In order to remove such heavy metals, There is a need for an unnecessary process of controlling the pH such as treating acidic water and diluted water in fresh water and seawater.

However, in the case of using the heavy metal adsorption eliminator according to the present invention, there is no need for the step of adjusting the pH as described above. Therefore, the method of removing heavy metals is simple, and the steel slag, montmorillonite, ilite, kaolinite , And it was confirmed that the removal rate of the heavy metal was about 5 times or more superior to the untreated red mud (Experimental Example 1, Table 2).

In one embodiment of the present invention, the heavy metal adsorption eliminator is added in an amount of 4-20 w / v% based on 100 ppm of heavy metals in water.

According to one embodiment of the present invention, when the heavy metal adsorption eliminator is added in an amount of less than 4 w / v% based on 100 ppm of the heavy metal, there may be a problem that the removal rate of the heavy metal is lowered, There is a problem that the adsorption amount per unit mass is rather reduced without increasing the removal rate of the heavy metal.

In another embodiment of the present invention, the heavy metal adsorption eliminator has an average particle size of 60-150 [mu] m.

According to one embodiment of the present invention, when the average particle diameter of the heavy metal adsorption eliminator is less than 60 탆, there may be a problem of suspended in water, and when it is more than 150 탆, there may be a problem of decreasing the adsorption rate.

In another embodiment of the present invention, the heavy metal is at least one selected from the group consisting of chromium, arsenic, selenium, molybdenum, and vanadium, and the heavy metal is preferably hexavalent chromium ion.

According to an embodiment of the present invention, the heavy metal adsorption eliminator may be selected from the group consisting of Cr ₄ ^{2 -} , HAsO ₄ ^{2 -} , SeO ₄ ^{2 -} , MoO ₄ ^{2 -} , HVO ₄ ^{2 -} , H ₂ VO ₄ ^- Cr is present in an anion (VI), as (V) , Se (VI), Mo (VI), heavy metals, such as V (V) is adsorbed to form Al ^{3 +,} Fe ^{3 +} and outer-sphere compound of the red mud And is excellent in the removal of heavy metals, and particularly excellent in the adsorption performance of hexavalent chromium.

Hereinafter, the present invention will be described in more detail with reference to Examples and the like, but the scope and content of the present invention can not be construed to be limited or limited by the following Examples. In addition, it is apparent that, based on the teachings of the present invention including the following examples, those skilled in the art can easily carry out the present invention in which experimental results are not specifically shown.

In order to compare the adsorption capacity of steel slag, montmorillonite, illite, kaolinite, red mud and hexavalent chromium (Cr ^{6 +} ) which are commonly used as conventional adsorbents, The following experiment was performed.

material

The steelmaking slag used in the steelmaker slag supplied by Eco Meister Co., Ltd. was used to remove foreign matter from the naked eye without washing. Montmorillonite was manufactured by Sigma Aldrich of USA, and Ilite and Kaolinite were used by Fluka without separate washing and granulation. Red mud was red mud from KC corporation in Youngam, Jeonnam.

Example  1: into the mountains Preprocessed  Red mud adsorbent ( ATRM -2.0M) manufacture

1 kg of red mud to 10 L of 2.0 M HCl was added, and the mixture was stirred for 24 hours. After that, it was washed three times with distilled water and dried at 105 ° C for 24 hours. Sieves were sieved with 230 and 120 sieves, and the sieves were sieved with a particle size distribution of 63-125 μm.

XRF (S8 Tiger 4K, Bruker, Germany) analysis was performed to identify the chemical constituents of ATRM-2.0M.

division ATRM-2.0 M
Component content (%) Al ₂ O ₃ 21.21 Fe ₂ O ₃ 58.49 SiO ₂ 5.48 TiO ₂ 11.30 Cl  1.73 LOI ^* 1.79 Total 100

*: Loss on Ignition

As shown in Table 1, it was confirmed that the ATRM-2.0 M adsorbent according to the present invention occupies 97% or more of Fe ₂ O ₃ , Al ₂ O ₃ , SiO ₂ , and TiO ₂ as major constituents.

Comparative Example  1 and 2: as an acid Preprocessed  Red mud adsorbent ( ATRM -0.5M and ATRM -1.0M)

The same procedure was followed as in Example 1 except that 0.5 M HCl and 1.0 M HCl were used instead of 2.0 M HCl to prepare red mud adsorbents pretreated with acid.

Experimental Example  One: Ash experiment

After the experiment, all samples were centrifuged at 1300 rpm for 3 minutes (CF-10, Wisespin, Korea) and filtered through a 0.45 μm syringe filter (Whatman 0.45 μm pp filter, USA). The filtered sample was developed with a diphenylcarbazide solution and the residual concentration was measured with a UV-vis spectrophotometer (Shimadzu, UV-1201, Japan).

(1) Comparison of adsorption capacity of hexavalent chromium (Cr ^{6 +} ) according to adsorbent type

6 of the adsorbent chromium (Cr ^{6 +)} 6 of 50 mg / L concentration for comparison adsorbability into a chromium (Cr ^{6 +)} solution (pH 3.4) 30 ml to a 50 ml tube, by injecting each adsorbent 1 g 25 Deg.] C, 100 rpm for 24 hours. The hexavalent chromium (Cr ^{6 +} ) solution was prepared by adding CrO ₃ (Junsei) to the third distilled water and adjusting the ionic strength to 1000 mg / L in 0.02 M KCl solution. 0.02 M KCl solution.

The removal rate (%) of hexavalent chromium (Cr ^{6 +} ) after 24 hour reaction of steelmaking slag, montmorillonite, ilite, kaolinite, red mud, ATRM-0.5M, ATRM-1.0M and ATRM- , And the results are shown in Table 2 and Fig.

In Equation (2)

C ₀ is the concentration (mg / L) of hexavalent chromium (Cr ^{6 +} ) in the liquid phase in the initial state,

C is the concentration (mg / L) of hexavalent chromium (Cr ^{6 +} ) in a liquid state in an equilibrium state.

division Removal rate (%) Example 1 ATRM-2.0 M 67.5% Comparative Example 1 ATRM-0.5 M 5.2% Comparative Example 2 ATRM-1.0 M 9.7% Comparative Example 3 Untreated reddish brown 0.5% Comparative Example 4 Ilright 15.2% Comparative Example 5 Montmorillonite 13.1% Comparative Example 6 Steel slag 10.5% Comparative Example 7 Kaolinite 7.24%

As shown in Table 2 above, the ATRM-2.0 M (67.5%) according to the present invention showed the highest removal rate of hexavalent chromium (Cr ^{6 +} ), and in Comparative Examples 1 to 7, Was found to exhibit chromium (Cr ^{6 +} ) removal. Particularly, as in Example 1 of the present invention, in the case of red mud ATRM-0.5 M and ATRM-1.0 M pretreated with an acid, the removal rate of hexavalent chromium (Cr ^{6 +} ) was not less than 10% (Cr ^{6 +} ) adsorption was not observed at all.

As shown in Table 2 above, the adsorption capacity of hexavalent chromium (Cr ^{6 +} ) of the adsorbent was compared with that of ATRM-2.0M which showed high adsorption efficiency. Experiments were conducted according to the characteristics of equilibrium adsorption and pH change of the solution, Experiments were performed.

(2) Adsorption characteristics according to maximum adsorption capacity and concentration of adsorbent

The equilibrium adsorption experiments were carried out in order to investigate the adsorption characteristics depending on the maximum adsorptivity and concentration of the adsorbent. The equilibrium adsorption experiments were carried out in a 50 ml tube filled with 1 g of ATRM-2.0 M at 25, 50, 100, 200 and 400 mg / ^{6 +)} solution (pH 7) into a 30 ml thermostatic agitator (SJ-808SF, Sejong scientific CO ., then stirred for 24 hours under the conditions of 25 ℃, 100 rpm using a Korea) were analyzed for residual levels.

The equilibrium adsorption test results were analyzed using the Freundlich model and the Langmuir model as shown in the following equations (3) and (4), and the results are shown in Table 3 and FIG.

In the above equations (3) and (4)

S is the amount (mg / g) of Cr ^{6 +} adsorbed per unit mass of adsorbent,

C is the concentration (mg / L) of hexavalent chromium (Cr ^{6 +} ) in the liquid phase in an equilibrium state,

K _F is the partition coefficient (L / g)

N is a Freundlich constant,

K _L is the Langmuir adsorption constant (L / mg) associated with the binding energy,

Q _m is the maximum adsorption amount (mg / g) of hexavalent chromium (Cr ^{6 +} ) per unit mass of adsorbent.

The values of K _F , n, K _L and Q _m were obtained by applying the Freundlich model and the Langmuir model to the experimental results.

absorbent ATRM-2.0 M Freundlich model KF (L / g) 0.620 1 / n 0.202 R ² 0.962 Langmuir model Qm (mg / g) 1.810 Km (L / mg) 7.244 R ² 0.898

(In Table 3, R ² is a coefficient of determination.)

As shown in Table 3, in the Freundlich model, the partition coefficient (K _F ) was 0.620 L / g, and the 1 / n value indicating the adsorption tendency between particles and contaminants was 0.202.

Generally, it is known that 1 / n, which indicates the adsorption tendency, shows a strong adsorption tendency when it is less than 0.5 (Edzwald, J., 2011. In Water Quality & Treatment: A Handbook on Drinking Water , 6th Ed. American Water Works Association), and since the adsorbent of the present invention is 0.02, it can be usefully used as an adsorbent.

On the other hand, the maximum adsorption amount (Q _m ) was 1.810 mg / g in the Langmuir model and the adsorption constant (K _m ) indicating the adsorption affinity was 7.244 L / mg. The R ² of the Langmuir model is 0.898 and the R ² value of the Freundlich model is 0.962. The adsorption of hexavalent chromium (Cr ^{6 +} ) by ATRM-2.0 M is more dependent on the Freundlich model assuming multiple adsorption than the Langmuir model (Cr ^{6 +} ) adsorption of ATRM-2.0 M is composed of multiple layers.

(3) Adsorption characteristics by pH

In order to investigate the adsorption characteristics by pH, 100 mg / L hexavalent chromium (Cr ^{6 +} ) solution was added at pH 3, 5, 7 (using Sevenmulti S40, Mettler Toledo, Switzerland) with 0.1 M HCl and 0.1 M KOH , 9, and 11, respectively. The agitation time, the amount of the adsorbent, and the volume of the solution were experimentally performed under the same conditions as the equilibrium adsorption. The results are shown in Table 4 and FIG.

Condition Of ATRM-2.0M
The adsorption amount per unit mass pH 3 1.334 mg / g pH 5 1.398 mg / g pH 7 1.274 mg / g pH 9 1.308 mg / g pH 11 1.358 mg / g

As shown in Table 4 and FIG. 3, the adsorption amount per unit mass of the solution was about 1.3-1.4 mg / g according to the pH of the solution, and it was confirmed that the initial pH of the solution had little effect on the adsorption amount per unit mass .

Conventionally, hexavalent chromium (Cr ⁶⁺ ) is present as an anion of CrO ₄ ^{2 -} , HCrO ₄ ^- , and Cr ₂ O ₇ ^{2 - in} the aqueous solution and is adsorbed while forming Al ^{3 +} , Fe ^{3 +} and outer- And it is confirmed that the adsorption amount is not changed even at a high pH condition, contrary to the result of the previous study that the pH is high and compete with OH ^- to lower the removal rate. In contrast, the ATRM-2.0 M adsorbent After 24 hours, it was confirmed that the pH was in the range of 4.13-4.48, and the change of pH was not large.

(4) Adsorption characteristics according to adsorbent injection amount

2, 3, 5, 7, and 9 g of ATRM-2.0 M were injected into 30 mL of 100 mg / L hexavalent chromium (Cr ^{6 +} ) solution for 24 hours. Respectively. The results are shown in Table 5 and FIG.

ATRM-2.0 M
Addition amount Removal rate (%) The adsorption amount per unit mass 1 g 42.5% 1.274 mg / g 2 g 80.2% 1.203 mg / g 3 g 92.2% 0.922 mg / g 5 g 97.6% 0.586 mg / g 7 g 100% 0.427 mg / g 9 g 100% 0.333 mg / g

As shown in Table 5 and FIG. 4, as the injection amount of ATRM-2.0 M increased from 1 g to 9 g, the total removal rate of hexavalent chromium (Cr ^{6 +} ) increased from 42.5% to 100% The adsorption amount per unit mass decreased from 1.274 mg / g to 0.333 mg / g. As the amount of adsorbent is increased, the removal rate of hexavalent chromium (Cr ^{6 +} ) increases, but the adsorption amount per unit mass decreases.

(5) Adsorption tendency according to mixing use of ATRM-2.0 M adsorbent

In order to investigate the adsorption tendency of ATRM-2.0 M with different adsorbents, ATRM-2.0 M was mixed with 0.5 g each of zeolite, oyster shell, limestone or montmorillonite to obtain 100 mg / L hexavalent chromium Cr ^{6 +} ) solution. The agitation time and the volume of the solution were carried out under the same conditions as the equilibrium adsorption. The results are shown in Table 6 and FIG.

division The adsorption amount per unit mass ATRM-2.0 M 1.274 mg / g ATRM-2.0 M + untreated red mite 1.066 mg / g ATRM-2.0 M + Zeolite 0.834 mg / g ATRM-2.0 M + oyster closure 0.385 mg / g ATRM-2.0 M + limestone 0.328 mg / g ATRM-2.0 M + montmorillonite 0.824 mg / g

As shown in Table 6 and FIG. 5, when ATRM-2.0 M according to the present invention was mixed with untreated red mud, 1.066 mg / g was obtained. When ATRM-2.0 M and zeolite were mixed, 0.834 mg / g, ATRM-2.0 M and 0.355 mg / g for mixed use of oyster hull, 0.328 mg / g for mixed use of ATRM-2.0 M and limestone, and 0.824 mg / g for ATRM-2.0 M and montmorillonite mixed Respectively. It has been found that the use of ATRM-2.0 M alone in the adsorption removal of hexavalent chromium (Cr ^{6 +} ) has a higher removal rate than that of mixed use with other adsorbent materials.

It is considered that the mixing of the other adsorbent materials has a higher pH than the use of ATRM-2.0M alone, which has a very negative effect on the removal of hexavalent chromium (Cr ^{6 +} ) in the aqueous solution due to the increase of OH ^- .

(6) Cr ^{6 +} removal characteristics of ATRM-2.0 M in seawater

In order to investigate the Cr ^{6 +} removal characteristics of ATRM-2.0 M in seawater, seawater taken from Jeongok Port, Hwaseong City, Gyeonggi Province was used for the post-filtration experiments in 3 μm quantitative filter paper (Advantes, NO. The electrical conductivity of seawater used in the experiment is 21.3 ms / cm and the pH is 7.4. 30 mL of a solution (pH 7) diluted to 100 mg / L in seawater and distilled water was injected into a 50 mL tube, and 1 g of ATRM-2.0 M was added. The mixture was stirred for 24 hours under the same conditions as the other tests. The results are shown in Table 7 and FIG.

division The adsorption amount per unit mass Distilled water 1.274 mg / g sea water 1.113 mg / g

As shown in Table 7 and FIG. 6, the adsorption amounts of ATRM-2.0 M in distilled water and seawater were 1.274 mg / g and 1.113 mg / g, respectively, and the adsorption performance per unit mass of seawater in distilled water and sea water Since there is no difference, it can be useful for removing heavy metals in fresh water and seawater environment.

Claims (17)

A heavy metal adsorption eliminator comprising red mud which has been pretreated with an aqueous acid solution having an ion concentration of 1.5-3.0 M of oxonium (H ₃ O ⁺ ) ion.
The method according to claim 1,
Wherein the heavy metal adsorption eliminator is added in an amount of 4-20 w / v% based on 100 ppm of the heavy metal.
The method according to claim 1,
Wherein the heavy metal adsorption eliminator has a heavy metal adsorption amount of 1-2 mg / g.
The method according to claim 1,
Wherein the heavy metal adsorption eliminator has an average particle diameter of 60 to 150 占 퐉.
The method according to claim 1,
Wherein the acid aqueous solution is at least one acid aqueous solution selected from hydrochloric acid, nitric acid, sulfuric acid and acetic acid.
The method according to claim 1,
Wherein the heavy metal is at least one selected from the group consisting of chromium, arsenic, selenium, molybdenum, and vanadium.
The method according to claim 1,
Wherein the heavy metal is a hexavalent chromium ion.
The method according to claim 1,
Wherein the heavy metal adsorption eliminator is for adsorbing and removing heavy metals in seawater or fresh water.
(1) adding red mud to an aqueous acid solution having an ion concentration of 1.5-3.0 M of oxonium (H ₃ O ⁺ ) ion and stirring;
(2) The method for producing heavy metal adsorbent of (1), wherein the red mud pretreated with the acid obtained in the step (1) is washed with distilled water and then dried.
10. The method of claim 9,
Wherein the red mud is added in an amount of 1 to 50 parts by weight based on 100 parts by weight of the aqueous acid solution in the step (1).
10. The method of claim 9,
In the step (1), the acid aqueous solution is at least one acid aqueous solution selected from hydrochloric acid, nitric acid, sulfuric acid and acetic acid.
10. The method of claim 9,
Wherein the drying in step (2) is performed at a temperature of 80-150 < 0 > C.
A method for removing heavy metals in a water comprising the step of introducing heavy metal adsorbent of claim 1 into seawater or fresh water to remove heavy metals by an adsorption reaction.
14. The method of claim 13,
Wherein the heavy metal adsorption eliminator is added in an amount of 4-20 w / v% based on 100 ppm of heavy metals in the water.
14. The method of claim 13,
Wherein the heavy metal adsorption eliminator has an average particle size of 60-150 占 퐉.
14. The method of claim 13,
Wherein the heavy metal is at least one selected from the group consisting of chromium, arsenic, selenium, molybdenum, and vanadium.
14. The method of claim 13,
Wherein the heavy metal is a hexavalent chromium ion.

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