KR102473847B1 - A molded article for water quality improvement comprising activated carbon - Google Patents

Abstract

The present invention relates to an oxygen-generating composition containing activated carbon, and more specifically, to an oxygen-generating composition containing cement, sand, activated carbon, red clay, and water. The oxygen-generating composition of the present invention can gradually release oxygen into the air or water to increase the oxygen concentration in the water for a long period of time, exhibit antibacterial properties against germs and bacteria, remove green algae, purify contaminated water, and promote the growth of plants. In addition, the present invention can be manufactured in a liquid state, a powder state, a molded body, and the like, and used for supplying oxygen to fish farms, fish tanks, and the like, or to remove green algae and improve water quality, or to promote plant growth in pots, crops, and the like.

Description

Molded article for water quality improvement comprising activated carbon {A molded article for water quality improvement comprising activated carbon}

The present invention relates to an oxygen-generating composition containing activated carbon, and more particularly, to an oxygen-generating composition containing cement, sand, activated carbon, loess and water.

Oxygen-generating materials are used for supplying oxygen in emergency situations where in-flight pressure drops, emergency evacuation due to fire, and long-term work required in an enclosed space.

Materials that generate oxygen include lithium perchlorate (LiClO ₄ ), lithium chlorate (LiClO ₃ ), sodium perchlorate (NaClO ₄ ), sodium chlorate (NaClO ₃ ), potassium perchlorate ( There are potassium perchlorate, KClO ₄ ), potassium chlorate (KClO ₃ ), and the like, and these materials are known to generate salt and oxygen while decomposing when heated by an electrical or chemical method.

However, conventional oxygen generating materials generate excessive heat in the oxygen generating process, which causes oxygen generating molded bodies to fuse with each other, and surface hardening occurs due to a strong oxidation reaction, so that the oxygen generating material inside does not react.

Therefore, it is necessary to develop an oxygen-generating composition that can increase the oxygen concentration in water for a long period of time by gradually releasing oxygen into the air or water, exhibits antibacterial properties against germs or bacteria, and can remove algae and purify contaminated water. .

Korean Patent Publication No. 10-2018-0085334 Korean Patent Publication No. 10-2022-0081037

The present invention is to solve the problems of the prior art, and can increase the oxygen concentration in the water for a long period of time by gradually discharging oxygen into the air or water, exhibit antibacterial properties against germs or bacteria, remove algae and polluted water It is an object of the present invention to provide an oxygen generating composition capable of purifying and promoting the growth of plants.

In addition, the present invention is manufactured in a liquid state, powder state, molded body, etc., and is used for supplying oxygen to fish farms, fish tanks, etc., used for removing algae and improving water quality, or used for promoting plant growth in pots, crops, etc. It is an object of the present invention to provide an oxygen generating composition.

In order to achieve the above object, the present invention provides an oxygen generating composition including cement, sand, activated carbon, loess and water.

In one embodiment of the present invention, the composition comprises 70 to 120 parts by weight of sand, 5 to 30 parts by weight of activated carbon, 5 to 20 parts by weight of loess, and 1 to 20 parts by weight of water based on 100 parts by weight of cement. do.

In one embodiment of the present invention, the composition comprises 1 to 10 parts by weight of a copolymer of an acrylate group-containing silane coupling agent, 2-hydroxyethyl acrylate (HEA) and 2-hydroxyethyl methacrylate (HEMA) It is characterized in that it further includes.

In one embodiment of the present invention, the activated carbon may include (a) a first carbonization step of carbonizing rice hulls to produce a first carbonized material;

(b) a secondary carbonization step of carbonizing the primary carbide to produce a secondary carbide;

(c) a tertiary carbonization step of carbonizing the secondary carbide to produce a tertiary carbide; and

(d) characterized in that it is produced by a method comprising the step of grinding the tertiary carbide.

In addition, the present invention provides a molded article containing the oxygen generating composition.

The present invention can increase the oxygen concentration in the water for a long period of time by slowly discharging oxygen into the air or water, exhibit antibacterial properties against germs or bacteria, remove algae and purify contaminated water, and promote plant growth. It is possible to provide an oxygen generating composition capable of

In addition, the present invention is manufactured in a liquid state, powder state, molded body, etc., and is used for supplying oxygen to fish farms, fish tanks, etc., used for removing algae and improving water quality, or used for promoting plant growth in pots, crops, etc. It is possible to provide an oxygen generating composition that is.

The present invention will be described in detail based on the following examples. The terms, examples, etc. used in the present invention are merely exemplified to explain the present invention in more detail and help the understanding of those skilled in the art, and the scope of the present invention should not be construed as being limited thereto.

Technical terms and scientific terms used in the present invention represent meanings commonly understood by those of ordinary skill in the art to which this invention belongs, unless otherwise defined.

The present invention relates to an oxygen generating composition comprising cement, sand, activated carbon, loess and water.

The composition may include 70 to 120 parts by weight of sand, 5 to 30 parts by weight of activated carbon, 5 to 20 parts by weight of loess, and 1 to 20 parts by weight of water, based on 100 parts by weight of cement.

The cement acts as a binder binding the composition, and known cements such as Portland cement, slag cement, alumina cement, gypsum cement, and plastic cement may be used without limitation.

The sand is used to improve oxygen release characteristics and durability, and is preferably used in an amount of 70 to 120 parts by weight based on 100 parts by weight of cement.

When the content of sand satisfies the above numerical range, oxygen release characteristics, antibacterial properties, adsorption properties, and durability can be maximized.

The activated carbon is used to improve oxygen release characteristics, antibacterial properties and adsorption, and is preferably used in an amount of 5 to 30 parts by weight based on 100 parts by weight of cement.

When the content of activated carbon satisfies the above numerical range, oxygen release characteristics, antibacterial properties, and adsorption properties can be maximized.

The activated carbon includes (a) a first carbonization step of carbonizing rice hulls to produce a first carbonized material;

(b) a secondary carbonization step of carbonizing the primary carbide to produce a secondary carbide;

(c) a tertiary carbonization step of carbonizing the secondary carbide to produce a tertiary carbide; and

(d) it can be produced by a method comprising the step of grinding the tertiary carbide.

The step (a) is the first carbonization step of carbonizing rice hull to produce primary carbonized material. The temperature is raised from 100 ° C. to 300 ° C., and maintained at 300 ° C. for 30 minutes to 3 hours to first carbonize rice hull.

The first carbonization step may be performed under an inert gas, and nitrogen, argon, neon, helium, or the like may be used as the inert gas.

The inert gas may be injected at a rate of 10 ml/min to 100 ml/min, and when the injection rate satisfies the above numerical range, oxygen emission characteristics, antibacterial properties, adsorption properties, and the like can be maximized.

The first carbonization step may remove moisture, volatile components, impurities, etc. contained in the rice hull.

The heating rate of the first carbonization step is preferably 1 ° C./min to 10 ° C./min. When the heating rate satisfies the numerical range, oxygen release characteristics, antibacterial properties, adsorption properties, and the like can be maximized.

In addition, in the present invention, rice hull and rice bran may be simultaneously used as raw materials for activated carbon, and the weight ratio of rice hull and rice hull is preferably 100:1 to 20.

When the weight ratio of rice husk and rice husk satisfies the above numerical range, oxygen release characteristics, antibacterial properties, adsorption properties, and the like can be maximized.

In addition, in the present invention, rice hull, rice bran, and rice straw may be simultaneously used as raw materials for activated carbon, and the weight ratio of rice hull, rice bran, and rice straw is preferably 100:1 to 20:1 to 10.

When the weight ratio of rice hull, rice hull, and rice straw satisfies the above numerical range, oxygen release characteristics, antibacterial properties, adsorption properties, and the like can be maximized.

In addition, rice hull, rice bran, rice straw, and sawdust may be simultaneously used as raw materials for activated carbon in the present invention, and the weight ratio of rice hull, rice bran, rice straw, and sawdust is preferably 100:1 to 20:1 to 10:1 to 5.

When the weight ratio of rice hull, rice hull, rice straw, and sawdust satisfies the above numerical range, oxygen release characteristics, antibacterial properties, adsorption properties, and the like can be maximized.

The step (b) is a secondary carbonization step of carbonizing the primary carbide to produce a secondary carbide. can

The second carbonization step may be performed under an inert gas, and nitrogen, argon, neon, helium, or the like may be used as the inert gas.

The inert gas may be injected at a rate of 10 ml/min to 100 ml/min, and when the injection rate satisfies the above numerical range, oxygen emission characteristics, antibacterial properties, adsorption properties, and the like can be maximized.

The temperature increase rate of the second carbonization step is preferably 1 ° C / min to 10 ° C / min, and when the temperature increase rate satisfies the above numerical range, oxygen release characteristics, antibacterial properties, adsorption properties, etc. can be maximized.

In the second carbonization step, steam or carbon dioxide may be injected, and the steam or carbon dioxide may be injected at a rate of 0.1 ml / h to 0.5 ml / h, and when the injection rate satisfies the above numerical range, oxygen emission characteristics , antimicrobial activity, adsorption, etc. can be maximized.

The steam or carbon dioxide can increase the pores and specific surface area of the activated carbon by removing organic and inorganic substances contained in the rice hull.

The step (c) is a tertiary carbonization step of carbonizing the secondary carbide to produce a tertiary carbide. can

The third carbonization step may be performed under an inert gas, and nitrogen, argon, neon, helium, or the like may be used as the inert gas.

The inert gas may be injected at a rate of 10 ml/min to 100 ml/min, and when the injection rate satisfies the above numerical range, oxygen emission characteristics, antibacterial properties, adsorption properties, and the like can be maximized.

The temperature increase rate of the tertiary carbonization step is preferably 1 ° C / min to 10 ° C / min, and when the temperature increase rate satisfies the above numerical range, oxygen release characteristics, antibacterial properties, adsorption properties, etc. can be maximized.

In the third carbonization step, steam or carbon dioxide may be injected, and the steam or carbon dioxide may be injected at a rate of 0.5 ml / h to 1 ml / h, and when the injection rate satisfies the above numerical range, oxygen emission characteristics , antimicrobial activity, adsorption, etc. can be maximized.

The steam or carbon dioxide can increase the pores and specific surface area of the activated carbon by removing organic and inorganic substances contained in the rice hull.

In addition, in the present invention, steam and carbon dioxide can be used simultaneously, and the volume ratio of steam and carbon dioxide is preferably 60 to 80:20 to 40.

When the volume ratio of water vapor and carbon dioxide satisfies the above numerical range, oxygen release characteristics, antibacterial properties, adsorption properties, and the like can be maximized.

The step (d) is a step of crushing the tertiary carbide. Activated carbon having a certain size can be obtained by cooling the prepared tertiary carbide and then pulverizing the tertiary carbide using a known crushing means.

The pulverized activated carbon may be dried through a known drying means, through which the moisture content of the activated carbon may be adjusted.

In addition, in the present invention, after the step (d), the surface of the activated carbon is coated with a silane coupling agent containing an acrylate group, a copolymer of 2-hydroxyethyl acrylate (HEA) and 2-hydroxyethyl methacrylate (HEMA) It can be treated with, and the copolymer can improve the adsorption properties and bonding strength of activated carbon.

The acrylate group-containing silane coupling agent includes 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltri ethoxysilane, 3-acryloxypropyltrimethoxysilane, methacryloxymethyltriethoxysilane, methacryloxymethyltrimethoxysilane and the like.

The weight ratio of the acrylate group-containing silane coupling agent, 2-hydroxyethyl acrylate (HEA) and 2-hydroxyethyl methacrylate (HEMA) is preferably 2 to 10:100:20 to 50, and the above numerical values In the range, binding force and adsorption characteristics can be maximized.

The copolymer is used in an amount of 2 to 10 parts by weight based on 100 parts by weight of activated carbon. When the content is less than 2 parts by weight, the effect of addition is insignificant, and when the content exceeds 10 parts by weight, the specific surface area is reduced.

In addition, in the present invention, after step (d), the surface of the activated carbon is treated with an acrylate group-containing silane coupling agent, an acrylic acid monomer, 2-hydroxyethyl acrylate (HEA) and 2-hydroxyethyl methacrylate (HEMA) ), and the copolymer can improve adsorption properties and bonding strength of activated carbon.

The acrylic acid-based monomers include acrylic acid, methacrylic acid, carboxyl ethyl acrylate, carboxyl ethyl methacrylate, carboxyl pentyl acrylate, carboxyl pentyl methacrylate, itaconic acid, maleic acid, fumaric acid, methyl acrylic acid, ethyl acrylic acid, Butyl acrylic acid, 2-ethylhexyl acrylic acid, decyl acrylic acid, methyl methacrylic acid, ethyl methacrylic acid, butyl methacrylic acid, 2-ethylhexyl methacrylic acid, decyl methacrylic acid and the like.

The weight ratio of the silane coupling agent containing an acrylate group, acrylic acid monomer, 2-hydroxyethyl acrylate (HEA) and 2-hydroxyethyl methacrylate (HEMA) is 2 to 10:30 to 60:100:20 to 50 is preferred.

The copolymer is used in an amount of 2 to 10 parts by weight based on 100 parts by weight of activated carbon. When the content is less than 2 parts by weight, the effect of addition is insignificant, and when the content exceeds 10 parts by weight, the specific surface area is reduced.

The activated carbon has excellent oxygen emitting properties, antibacterial properties, adsorption properties, nonflammability, insulation properties, and deodorizing properties, and is inexpensive, so it can be effectively used in the fields of oxygen emitting materials, nonflammable materials, heat insulating materials, adsorbents, and catalysts.

The ocher is used to improve oxygen release characteristics, deodorizing characteristics and antibacterial properties, and is preferably used in an amount of 5 to 20 parts by weight based on 100 parts by weight of cement.

When the content of loess satisfies the above numerical range, oxygen emission characteristics, deodorizing characteristics and antibacterial properties can be maximized.

The water is used to adjust the concentration of the composition and harden the composition, and the water content is preferably 1 to 20 parts by weight based on 100 parts by weight of cement.

When the water content satisfies the above numerical range, oxygen release characteristics, adsorption properties, durability and antibacterial properties can be maximized.

In addition, the composition may further include a silane coupling agent containing an acrylate group, a copolymer of 2-hydroxyethyl acrylate (HEA) and 2-hydroxyethyl methacrylate (HEMA).

The weight ratio of the acrylate group-containing silane coupling agent, 2-hydroxyethyl acrylate (HEA) and 2-hydroxyethyl methacrylate (HEMA) is preferably 2 to 10:100:20 to 50.

It is preferable to use 1 to 10 parts by weight of the copolymer based on 100 parts by weight of cement, and when the content of the copolymer satisfies the above numerical range, oxygen release characteristics, adsorption properties, durability and antibacterial properties can be maximized.

In addition, the composition may further include a copolymer of an acrylate group-containing silane coupling agent, an acrylic acid monomer, 2-hydroxyethyl acrylate (HEA) and 2-hydroxyethyl methacrylate (HEMA).

The weight ratio of the silane coupling agent containing an acrylate group, acrylic acid monomer, 2-hydroxyethyl acrylate (HEA) and 2-hydroxyethyl methacrylate (HEMA) is 2 to 10:30 to 60:100:20 to 50 is preferred.

It is preferable to use 1 to 10 parts by weight of the copolymer based on 100 parts by weight of cement, and when the content of the copolymer satisfies the above numerical range, oxygen release characteristics, adsorption properties, durability and antibacterial properties can be maximized.

In addition, the composition may further include a silane coupling agent oligomer prepared by reacting an acrylate group-containing silane coupling agent, an epoxy group-containing silane coupling agent, bisphenol A (BPA) and 2-hydroxyethyl acrylate (HEA). .

The epoxy group-containing silane coupling agent includes 2-glycidoxyethylmethyldimethoxysilane, 2-glycidoxyethylmethyldiethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropylmethyldiethoxy Silane, 2-glycidoxyethyltrimethoxysilane, 2-glycidoxyethyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 2-(3 ,4-epoxycyclohexyl)ethylmethyldimethoxysilane, 2-(3,4-epoxycyclohexyl)ethylmethyldiethoxysilane, 3-(3,4-epoxycyclohexyl)propylmethyldimethoxysilane, 3-( 3,4-epoxycyclohexyl)propylmethyldiethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltriethoxysilane, 3- (3,4-epoxycyclohexyl)propyltrimethoxysilane, 3-(3,4-epoxycyclohexyl)propyltriethoxysilane, and the like.

The weight ratio of the acrylate group-containing silane coupling agent, the epoxy group-containing silane coupling agent, bisphenol A (BPA), and 2-hydroxyethyl acrylate is preferably 2 to 10:100:10 to 30:20 to 50.

The oligomer preferably has a weight average molecular weight of 5,000 to 50,000 g/mol.

The oligomer is preferably used in an amount of 1 to 10 parts by weight based on 100 parts by weight of cement, and when the content of the oligomer satisfies the above numerical range, oxygen release characteristics, adsorption properties, durability and antibacterial properties can be maximized.

In addition, the composition may further include coal ash, and the coal ash is preferably used in an amount of 1 to 10 parts by weight based on 100 parts by weight of cement.

When the content of the coal ash satisfies the above numerical range, oxygen emission characteristics, adsorption properties, durability and antibacterial properties can be maximized.

In addition, the composition may further include a briquette material, and the briquette material is preferably used in an amount of 1 to 10 parts by weight based on 100 parts by weight of cement.

When the content of the briquette ash satisfies the above numerical range, oxygen release characteristics, adsorption properties, durability and antibacterial properties may be maximized.

In addition, the composition may further include shell particles, and as shells, oyster shells, beetle shells, clam shells, lily shells, abalone shells, and the like may be used without limitation.

The content of shell particles is preferably 1 to 10 parts by weight based on 100 parts by weight of cement, and when the content satisfies the above numerical range, oxygen release characteristics, adsorption properties, durability and antibacterial properties can be maximized.

In addition, the present invention relates to a molded article containing the oxygen generating composition.

The oxygen-generating composition can increase the oxygen concentration in the water for a long period of time or maintain it above a certain concentration by gradually releasing oxygen into the air or water, exhibit antibacterial properties against germs or bacteria, remove algae, and purify polluted water. and can promote plant growth.

The oxygen-generating composition is manufactured in a liquid state, powder state, molded body, etc., and is used for supplying oxygen to fish farms, fish tanks, etc., or used for algae removal and water quality improvement in seas, rivers, rivers, etc., or used for pollen, crops, etc. It can be used for stimulating plant growth.

The molded body is manufactured in various shapes such as pellet form, rod form, block form (sphere, cylinder, cone, pyramid, hexahedron, polyhedron, etc.) and put into fish farms, fish tanks, etc. to discharge oxygen for a long period of time to increase the amount of dissolved oxygen in water It can exhibit antimicrobial properties against germs or bacteria, can improve water quality, and can be used for promoting plant growth in pollen, crops, etc.

The molded article may be manufactured by mixing the oxygen generating composition and then compression molding, press molding, injection molding, extrusion molding, or the like.

In addition, the prepared molded body may be pulverized to be prepared in a powder state.

The present invention will be described in detail through Examples and Comparative Examples below. The following examples are only exemplified for the practice of the present invention, and the content of the present invention is not limited by the following examples.

(Example 1)

After drying the rice hull, removing impurities, and putting it into a carbonization device, the temperature was raised from 100 ° C to 300 ° C at a rate of 5 ° C / min, and maintained at 300 ° C for 1 hour to first carbonize the rice hull. At this time, nitrogen was injected at 50 ml/min.

The primary carbide was heated from 300 °C to 600 °C at a rate of 5 °C/min, and maintained at 600 °C for 1 hour to perform secondary carbonization. At this time, water vapor was injected at 0.3 ml/h while nitrogen was injected at 50 ml/min.

The secondary carbide was heated from 600 °C to 900 °C at a rate of 5 °C/min, and maintained at 900 °C for 1 hour to perform tertiary carbonization. At this time, water vapor was injected at 0.7 ml/h while nitrogen was injected at 50 ml/min.

The tertiary carbide was cooled and pulverized to prepare activated carbon.

An oxygen generating composition was prepared by mixing 100 parts by weight of cement, 100 parts by weight of sand, 15 parts by weight of the activated carbon, 10 parts by weight of loess, and 10 parts by weight of water.

(Example 2)

An oxygen generating composition was prepared in the same manner as in Example 1, except that activated carbon prepared using 100 parts by weight of rice hull and 10 parts by weight of rice hull was used instead of rice hull.

(Example 3)

5 parts by weight of 3-methacryloxypropyltrimethoxysilane, 100 parts by weight of 2-hydroxyethyl acrylate (HEA), and 30 parts by weight of 2-hydroxyethyl methacrylate (HEMA) were mixed and reacted to prepare a copolymer. did

Activated carbon was surface treated with the copolymer, and at this time, 5 parts by weight of the copolymer was used based on 100 parts by weight of the activated carbon.

An oxygen generating composition was prepared in the same manner as in Example 1, except that the surface-treated activated carbon was used.

(Example 4)

5 parts by weight of 3-methacryloxypropyltrimethoxysilane, 100 parts by weight of 2-hydroxyethyl acrylate (HEA), and 30 parts by weight of 2-hydroxyethyl methacrylate (HEMA) were mixed and reacted to prepare a copolymer. did

An oxygen generating composition was prepared in the same manner as in Example 1, except that 5 parts by weight of the copolymer was additionally used.

(Example 5)

5 parts by weight of 3-methacryloxypropyltrimethoxysilane, 100 parts by weight of 3-glycidoxypropyltrimethoxysilane, 20 parts by weight of bisphenol A (BPA) and 30 parts by weight of 2-hydroxyethyl acrylate (HEA) Oligomers were prepared by mixing and reacting. At this time, the weight average molecular weight of the oligomer was 30,000 g/mol.

An oxygen generating composition was prepared in the same manner as in Example 1, except that 5 parts by weight of the oligomer was additionally used.

(Comparative Example 1)

The rice hull was heated from 100 ° C to 900 ° C at a rate of 5 ° C / min, and maintained at 900 ° C for 1 hour to carbonize the rice hull. At this time, water vapor was injected at 0.3 ml/h while nitrogen was injected at 50 ml/min.

Activated carbon was prepared by cooling the carbide and then pulverizing it.

An oxygen generating composition was prepared in the same manner as in Example 1, except that the activated carbon was used.

(Comparative Example 2)

An oxygen generating composition was prepared in the same manner as in Example 1, except that activated carbon was not used.

A molded body having a hexahedral shape was prepared by compression molding the compositions prepared in Examples and Comparative Examples.

The molded body was put into a container containing river water, and turbidity, BOD, COD, total nitrogen and total phosphorus of the river water were measured one month after the molded body was added, and the results are shown in Table 1 below.

division river water Example comparative example One 2 3 4 5 One 2 turbidity
(NTU) 34.2 3.0 2.6 2.7 2.9 2.5 16.2 20.7 BOD
(mg/L) 96.0 11.8 9.6 10.9 10.5 9.7 36.5 32.0 COD
(mg/L) 40.5 13.0 11.4 11.2 11.3 10.1 24.6 21.4 Total Nitrogen (TN)
(mg/L) 27.3 11.5 9.9 10.2 9.6 9.1 16.3 18.2 total phosphorus (TP)
(mg/L) 3.8 0.5 0.4 0.4 0.5 0.3 1.4 1.5

From the results of Table 1, Examples 1 to 5 are excellent in oxygen emission characteristics and water quality improvement effects, and in particular, Examples 2 to 5 are the most excellent in the above characteristics.

On the other hand, it can be seen that Comparative Examples 1 and 2 are inferior to those of Examples.

Claims (5)

cement; sand; activated carbon; ocher; A silane coupling agent oligomer prepared by reacting an acrylate group-containing silane coupling agent, an epoxy group-containing silane coupling agent, bisphenol A (BPA), and 2-hydroxyethyl acrylate (HEA); And in the molded body for water quality improvement containing water,
The molded body contains 70 to 120 parts by weight of sand, 5 to 30 parts by weight of activated carbon, 5 to 20 parts by weight of loess, 1 to 10 parts by weight of the oligomer, and 1 to 20 parts by weight of water, based on 100 parts by weight of cement.
The activated carbon
(a) a first carbonization step of carbonizing rice hull to produce a first carbonized material;
(b) a secondary carbonization step of carbonizing the primary carbide to produce a secondary carbide;
(c) a tertiary carbonization step of carbonizing the secondary carbide to produce a tertiary carbide; and
(d) a molded body for water quality improvement characterized in that it is manufactured by a method comprising the step of grinding the tertiary carbide.
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