KR100237312B1 - Alginate water treatment agent containing activated carbon and method for producing the same - Google Patents

Abstract

The activated carbon-alginic acid gel water treatment agent of the present invention is added dropwise an aqueous solution of alginate and powdered activated carbon to a polyvalent cation solution to crosslink the activated carbon and alginic acid to prepare an activated carbon-alginic acid gel, and the activated carbon-alginic acid gel is dried to activate activated carbon-alginic acid. Prepare a gel water treatment. The aqueous solution of alginate and powdered activated carbon is preferably 0.1 to 5% by weight of alginate and 0.5 to 10% by weight of powdered activated carbon. Polyvalent cation solutions include CaCl ₂ , SrCl ₂ , BaCl ₂ and AlCl ₃ . According to the above method, the activated carbon-alginate gel water treatment agent may coat the surface with the alginate gel, thereby preventing the activated carbon from being released from the water treatment agent and increasing the adsorption efficiency of heavy metals. The method of coating the water treatment agent with an alginate gel is to wet the surface of the water treatment agent in an alginate solution of 0.1 to 2.0% by weight, take it out, and put it back into the polyvalent cation solution to coat the alginate gel.

Description

Alginate gel water treatment agent containing activated carbon and its manufacturing method

Figure 1 (a) is an electron micrograph of a magnification of 33 times the surface of the alginate gel beads containing activated carbon according to the present invention and (b) is an electron micrograph of a 1000 times magnification.

Figure 2 (a) is an electron micrograph of a 33 times magnification of the surface of the alginate gel beads containing activated carbon coated with the surface of the present invention and (b) is an electron micrograph of a 300 times magnification.

[Field of Invention]

The present invention relates to a water treatment agent and a method for producing the same, which are used in wastewater treatment and sewage treatment of sewage to remove toxic organic substances, heavy metals, odors and the like. More specifically, the present invention relates to an alginate gel water treatment agent containing activated carbon obtained by crosslinking alginate and powdered activated carbon using a polycation solution and drying the same.

Background of the Invention and Prior Art

In sewage treatment, activated carbon is mainly installed in a post-treatment process for the removal of hardly decomposable substances which are not treated in a biological treatment as a secondary treatment. In some cases, powdered activated carbon may be used together during chemical precipitation treatment. In Korea, there have been no reports of the use of activated carbon adsorption facilities in sewage treatment plants.However, it is impossible to recover the quality of river water, which is the source of drinking water, without the introduction of advanced facilities. The introduction of is expected.

In industrial wastewater treatment, as in the case of sewage treatment, advanced treatment after microbial treatment, physicochemical treatment without microbial treatment, and activated carbon treatment are used. In Korea, detailed report data on applying activated carbon to wastewater treatment is very high. It's rare. The chemical industry manufactures a wide variety of materials, so the plant wastewater is varied and the composition and concentration fluctuate greatly. In addition, many synthetic chemicals are difficult to biodegrade or toxic, so the characteristics of activated carbon adsorption are often utilized.

As the industrial society develops, pollution by heavy metals is increasing day by day in sewage as well as industrial wastewater. Therefore, modern sewage, that is, industrial wastewater, is seriously contaminated with heavy metals as well as taste and organic toxic substances, and requires its effective treatment.

Previously, these organic toxicants and heavy metals were treated in two stages, or heavy metals were not properly removed. If the removal of organic toxic substances and heavy metal ions is carried out in two stages, the process itself is inefficient and disadvantageously expensive. Activated carbon may be used to remove heavy metal ions (Korean Patent Publication No. 75-260), but activated carbon is not widely used for removing heavy metals due to its high ability to remove activated carbon. However, recently, a patent for a water treatment agent for removing heavy metals using alginic acid gel has been filed due to the excellent heavy metal removing ability of alginic acid gel. (Korean Patent Application No. 97-31780). However, alginic acid gels contain large amounts of water, which makes it difficult to handle and apply them. When the alginic acid gel is dried, the production form of the alginic acid gel is not only deformed, but the volume of the alginate gel is greatly reduced as the moisture is removed, thereby reducing the rate of adsorption of heavy metals.

In the field of water purifiers to remove contaminants from drinking water, reverse osmosis membranes have been used. Reverse osmosis membranes hold both organic and inorganic metals, but they do not have a selectivity, so they also catch minerals (calcium, potassium, magnesium, sodium) that are beneficial to the human body. In addition, because the processing flow rate is very slow, the use of a storage tank has a problem of breeding and contaminating general bacteria in the storage tank, and processing costs are very high because various devices are required. Recently, in order to overcome the disadvantages of the reverse osmosis membrane, the development of a direct type water purifier that can be directly connected to a faucet has been actively made. Water treatment apparatus that can be used in such a direct type water purifier includes a cartridge using hollow fiber membrane and activated carbon (Korean Patent Publication Nos. 92-11300 and 95-16813) and a cartridge using ion exchange resin and activated carbon (Korean Patent Publication). No. 94-13575). However, when using a cartridge using a hollow fiber membrane and activated carbon, there is a problem in that the removal efficiency of heavy metals is very low. When using a cartridge using ion exchange resin and activated carbon in a water purifier, there is a disadvantage in that the cost is high and the mineral metal is also caught.

As described above, the present inventors have urgently developed a water treatment agent that can efficiently solve the above-mentioned problems in the water treatment agent and direct-type water purifier that treats taste, organic toxic substances, and heavy metals efficiently in sewage and wastewater treatment. They have begun to develop an alginate gel water treatment agent containing the activated carbon of the present invention.

[Purpose of invention]

It is an object of the present invention to provide an alginate gel water treatment agent (hereinafter referred to as 'activated carbon-alginate gel water treatment agent') containing activated carbon used to remove toxic organic substances, heavy metals, and taste substances by being used in wastewater treatment and direct water treatment of sewage. will be.

Another object of the present invention is to provide an activated carbon-alginate gel water treatment agent capable of maintaining sufficient mechanical strength as a water treatment agent.

Still another object of the present invention is to provide an activated carbon-alginate gel water treatment agent which can form a gel to prepare a water treatment agent such as spherical or flat plate.

It is still another object of the present invention to provide an activated carbon-alginate gel water treatment agent that can be used as a filter filler in a direct type water purifier, including batch and continuous wastewater treatment.

The above and other objects of the present invention can be achieved by the present invention described below.

[Summary of invention]

The activated carbon-alginate gel water treatment agent of the present invention is added dropwise an aqueous solution of alginate and powdered activated carbon to a polyvalent cation solution to crosslink the activated carbon and alginic acid to prepare an activated carbon-alginate gel, and to dry the activated carbon-alginic acid gel to activate activated carbon-alginic acid. Prepare a gel water treatment.

The aqueous solution of alginate and powdered activated carbon is 0.1 to 5% by weight of alginate and 0.5 to powdered activated carbon.

It is preferable that it is -10 weight%. Polyvalent cation solutions include CaCl ₂ , SrCl ₂ , BaCl ₂ and AlCl ₃ .

The activated carbon-alginate gel water treatment agent prepared according to the above method may coat the surface with the alginate gel, thereby preventing the activated carbon from being released from the water treatment agent and increasing the adsorption efficiency of heavy metals. In the method of coating the water treatment agent with alginate gel, the surface of the water treatment agent is moistened in an alginate solution of 0.1 to 2.0% by weight, and then taken out of the polyhydric cation solution to coat the alginate gel.

The activated carbon-alginate gel water treatment agent of the present invention may be manufactured in the form of a spherical or flat plate type, and may also be used as a filter filler for a direct type water purifier, including batch and continuous type wastewater treatment.

The activated carbon-alginic acid gel water treatment agent of the present invention can be reused through desorption process after being used in a water treatment process.

Details of the present invention will be described in detail below.

Detailed Description of the Invention

The activated carbon-alginate gel water treatment agent of the present invention is added dropwise an aqueous solution of alginate and powdered activated carbon to a polyvalent cation solution to crosslink the activated carbon and alginic acid to prepare an activated carbon-alginic acid gel, and to dry the activated carbon-alginic acid gel to dry activated carbon-alginic acid. Prepare a gel water treatment.

Alginic acid is a linear polymer composed of mannuronic acid and gluronic acid, and sodium alginate is preferably used as the alginate.

The aqueous solution of alginate and powdered activated carbon is preferably 0.1 to 5% by weight of alginate and 0.5 to 10% by weight of powdered activated carbon. Polyvalent cation solutions include CaCl ₂ , SrCl ₂ , BaCl ₂ and AlCl ₃ . The polyvalent cation solution is preferably 0.1 to 50% by weight, preferably 0.5 to 10% by weight.

In the present invention, alginic acid gel can be manufactured and used in a suitable form such as spherical shape and flat shape. The smaller the activated carbon-alginate gel, the faster the adsorption and removal of odors, organic toxicants and heavy metals.

In view of the present invention from the alginate gel side, it is possible to remove the organic material and the like by forming a gel containing activated carbon at the same time, and also to keep the alginate gel in a dry state to facilitate storage and handling, and to fill the column or the like. Enable it.

When the present invention is viewed from the side of activated carbon, the powdered activated carbon, which is finished in one use, is included in the alginate gel to be formed to make activated carbon that can be recycled and retains the heavy metal removal characteristics of the alginate gel.

According to the above method, the activated carbon-alginate gel water treatment agent may coat the surface with the alginate gel, thereby preventing the activated carbon from being released from the water treatment agent and increasing the adsorption efficiency of heavy metals. In the method of coating the water treatment agent with alginate gel, the surface of the water treatment agent is moistened in an alginate solution of 0.1 to 2.0% by weight, and then taken out of the polyhydric cation solution to coat the alginate gel.

As described above, the activated carbon-alginate gel water treatment agent prepared in the present invention is a water treatment agent capable of simultaneously removing various contaminants such as toxic organic substances and heavy metals by the role of activated carbon and alginic acid in sewage and wastewater treatment. In particular, it can be used in filter cartridges for direct-type water purifiers, in which case it is a water treatment agent that has the characteristic of selectively removing heavy metal components without removing mineral metal and also removing toxic organic substances.

The invention will be further illustrated by the following examples, which are intended to illustrate the invention and are not intended to limit the protection scope of the invention.

Example 1

An aqueous solution of 1% by weight of sodium alginate and 4% by weight of powdered activated carbon was added dropwise to CaCl ₂ solution to prepare alginate gel beads containing activated carbon in a conventional manner. The beads thus prepared were dried at 60 ° C. to remove moisture to prepare spherical activated carbon-alginate gel adsorbents having a diameter of about 2.7 mm. The electron microscope photograph which enlarged the surface of the beads thus prepared by 33 times is the first (a) degree, and the image which was enlarged 1000 times is the first (b) degree.

Example 2

Activated carbon-alginic acid beads prepared by the method of Example 1 was put in a 0.2% by weight solution of sodium alginate to wet the surface and then taken out to CaCl ₂ solution to form an alginate gel coating. The beads were dried at 60 ° C. to obtain activated carbon-alginic acid beads with surface coating. The electron microscope photograph of the surface of the beads thus prepared is 33 times enlarged in FIG. 2 (a) and the enlarged image 300 times is shown in FIG. 2 (b).

[Adsorption Test of Heavy Metals and Minerals on Activated Carbon-Alginate Gel Water Treatment Agent of Example 2]

1 g of the surface-coated activated carbon-alginate gel beads prepared in the same manner as in Example 2 were added to 500 ml of heavy metal and mineral preparation water, followed by stirring to adsorb the result.

TABLE 1

NOTE 1) A minus sign in the production rate means an increase in mineral content.

2) Measurement of metal ion concentration: The concentration of each sample was measured by an atomic absorption analyzer.

[Column Packing Adsorption Test of Activated Carbon-Alginate Gel Water Treatment Agent of Example 2]

27 g of the surface-coated activated carbon-alginate gel beads prepared in the same manner as in Example 2 were charged into a cylindrical plastic column 23.7 cm long and 2.8 cm in diameter, and then a heavy metal preparation was flowed at a flow rate of 5 ml per minute. The results of the adsorption experiment are shown in Table 2.

TABLE 2

Note) Determination of heavy metal concentration: The heavy metal solution was started to flow into the column, and after each time the heavy metal solution discharged from the column was collected and the concentration of each heavy metal was measured by an atomic absorption analyzer.

[High Concentration Heavy Metal Adsorption Test of Activated Carbon-Alginate Gel Water Treatment Agent of Example 2]

1 g of the surface-coated activated carbon-alginic acid gel beads prepared in the same manner as in Example 2 were put into 100 ml of a high concentration of heavy metal preparation water, stirred, and adsorbed, and the results are shown in Table 3.

TABLE 3

[Organic Adsorption Test of Activated Carbon-Alginate Gel Water Treatment Agent of Example 2]

1 g of surface-coated activated carbon-alginate gel beads prepared in the same manner as in Example 2, each 100 ppm of benzoic acid, para-toluic acid, and isophthalic acid solution of 500 ppm After the adsorption was carried out by stirring in, the results are shown in Table 4.

TABLE 4

[Organic and Heavy Metal Adsorption Test of Activated Carbon-Alginate Gel Water Treatment Agent of Example 2]

In the same manner as in Example 2, 1 g of the surface-coated activated carbon-alginate gel beads were put in 50 ppm of manganese and para-toluic acid solution, and the organic and heavy metals were simultaneously removed, and the results are shown in Table 5.

TABLE 5

Simple modifications and variations of the present invention can be readily used by those skilled in the art, and all such variations or modifications can be considered to be included within the scope of the present invention.

Claims (10)

An activated carbon-alginic acid gel water treatment agent, which is prepared by crosslinking activated carbon and alginic acid by adding an aqueous solution of 0.1-5 wt% alginate and 0.5-10 wt% powdered activated carbon to a polyvalent cation solution. The activated carbon-alginate gel water treatment agent according to claim 1, wherein the alginate is sodium alginate. The activated carbon-alginate gel water treatment agent according to claim 1, wherein the polyvalent cation solution is selected from the group consisting of CaCl ₂ , SrCl ₂ , BaCl ₂ , and AlCl ₃ solutions. An aqueous solution of 0.1-5% by weight of alginate and 0.5-10% by weight of powdered activated carbon was added dropwise to the polyvalent cation solution to crosslink the activated carbon and alginic acid to prepare activated carbon-alginic acid gel; And drying the activated carbon-alginic acid gel; Method for producing an activated carbon-alginate gel water treatment agent, characterized in that consisting of steps. The method of claim 4, wherein the alginate is sodium alginate. The method of claim 4, wherein the polyvalent cation solution is selected from the group consisting of CaCl ₂ , SrCl ₂ , BaCl ₂ , and AlCl ₃ solutions. An aqueous solution of 0.1-5% by weight of alginate and 0.5-10% by weight of powdered activated carbon was added dropwise to the polyvalent cation solution to crosslink the activated carbon and alginic acid to prepare activated carbon-alginic acid gel; Drying the activated carbon-alginic acid gel; Wet the dried activated carbon-alginate gel with an alginate solution of 0.1-2.0% by weight; And coating the wet activated carbon-alginic acid gel again with a polyvalent cation solution; Method for producing an activated carbon-alginate gel water treatment agent, characterized in that consisting of steps. 8. The method of claim 7, wherein the alginate is sodium alginate. The method of claim 7, wherein the polyvalent cation solution is selected from the group consisting of CaCl ₂ , SrCl ₂ , BaCl ₂ , and AlCl ₃ solutions. Water treatment method characterized in that the activated carbon-alginate gel water treatment agent prepared according to any one of claims 4 to 9 is used as a filter filler for continuous or batch wastewater treatment or a direct water purifier for treating organic matter or heavy metals. .

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