KR102678135B1 - Activated carbon for water treatment and filter for water treatment containing the same - Google Patents

Abstract

The present invention relates to activated carbon for water treatment and a filter for water treatment containing the same, which has a BET specific surface area of 900 to 1,300 m ² /g and, in pore analysis by the DH method, a pore diameter in the range of 1 to 100 nm. The ratio of the pore volume of pores with a pore diameter of 2 nm or less out of the total pore volume is 80% or more, and in pore analysis by the MP method, the pore diameter of the total pore volume of pores with a pore diameter in the range of 0 to 2 nm is 80% or more. It relates to activated carbon for water treatment having a pore volume ratio of 0.8 nm or less of 85% or more and a water treatment filter containing the same.

Description

Activated carbon for water treatment and filter for water treatment containing the same {Activated carbon for water treatment and filter for water treatment containing the same}

The present invention relates to activated carbon for water treatment and a filter for water treatment containing the same. Activated carbon for water treatment having an activated carbon specific surface area and pore structure to improve the adsorption performance of low molecular compounds such as chloroform as an adsorbent for water treatment, and a filter containing the same. This relates to a water treatment filter.

Water is generally divided into drinking water, agricultural water, and industrial water depending on its use, and groundwater and river water are purified and used for various purposes. In particular, drinking water is produced and supplied through a multi-stage purification process such as filtration and sterilization of river water or groundwater. In the purification process, activated carbon is used to adsorb and remove various foreign substances contained in the water.

The activated carbon is an aggregate of amorphous carbon with well-developed micropores manufactured from wood, lignite, anthracite, and coconut shell as raw materials. During the activation process, micropores of the size of molecules are well formed, resulting in a large internal space. It is an adsorbent that has a large surface area. Activated carbon may have a surface area of more than 1,000 m ² per unit g, and the functional group of the carbon atom present on the surface has the property of adsorbing the molecules of the adsorbed substance by applying attractive force to the surrounding liquid or gas. Therefore, activated carbon is used in various industrial fields such as environment and water treatment.

In this way, activated carbon is a porous carbon material with numerous pores developed inside. The inner surface area of the pore layer is significantly large, and its surface is hydrophilic to impurities. Therefore, removal of soluble components as an adsorbed material requires soluble This is achieved by adsorbing the ingredients to the large internal surface of the pores.

The advanced water treatment market, which has so far been dominated by membrane separation and advanced oxidation technologies, is rapidly expanding in the global market as the application of activated carbon, which has a dramatically high adsorption capacity, has recently increased.

Due to the rapid increase in demand for activated carbon for advanced water treatment, Korea, which has a weak source of raw materials and a weak production base, is expected to face difficulties in the global water market. In order to increase the self-sufficiency of the domestic water industry, advanced water treatment, which can be considered a core technology, is needed. We are at a point where we need to accelerate research and development on highly efficient activated carbon as an adsorbent.

Meanwhile, sterilization of tap water with chlorine is mandatory for hygiene reasons. However, when chlorine added for sterilization purposes oxidizes and decomposes humin, a type of natural organic matter, it produces organochlorine compounds, which are carcinogenic, as a disinfection by-product. The 'disinfection by-products' are substances produced by the reaction between a disinfectant used in the purification of drinking water and organic compounds in the water, including disinfectants such as chlorine (Cl), chlorine dioxide (ClO ₂ ), and ozone ( When substances such as O ₃ ) are injected, they react with organic and inorganic substances in the water and are oxidized. As these substances are oxidized, products such as trihalomenthanes (THMs), aldehydes, and ketones are produced. do. These are called disinfection by-products. Most disinfection by-products detected in tap water are chloroform.

For this reason, activated carbon is being researched and developed to remove organic chlorine compounds, and in order to realize higher water purification ability, it is used to improve specific surface area or pore volume, as in Japanese Patent Laid-Open No. 2001-240407 and Japanese Patent No. 4628752. Various attempts have been made to improve the performance of activated carbon, but there are still limitations in satisfying the sufficient adsorption performance of low-molecular-weight organic chlorine compounds including chloroform.

In addition, conventional activated carbon filters are manufactured by combining a binder with activated carbon to prevent the generation of fine dust from activated carbon. However, in this case, the binder is worn away by the water being purified and detached during the water purification process. When dissolved in water, microplastics can be discharged along with purified water, which can cause health problems if ingested, and when the binder is worn and detached, activated carbon can be discharged as fine dust. , the problem of fine dust generation still remained.

According to this situation, the present invention seeks to provide a new activated carbon filter for water treatment that improves the adsorption performance of low-molecular-weight organic chlorine compounds such as chloroform without causing binder detachment or fine dust discharge problems.

Japanese Patent Publication No. 2001-240407 Japanese Patent Publication No. 4628752

The present invention was created to solve the above problems. Activated carbon for water treatment has excellent adsorption performance of low-molecular-weight organic chlorine compounds such as chloroform without causing binder detachment or fine dust discharge problems, and water treatment containing the same. The purpose is to provide a filter.

Activated carbon for water treatment according to an embodiment of the present invention has a BET specific surface area of 900 to 1,300 m ² /g, and in pore analysis by the DH method, the total pore volume of pores with a pore diameter in the range of 1 to 100 nm The ratio of the pore volume of pores with a pore diameter of 2.0 nm or less is 80% or more, and in pore analysis by the MP method, pores with a pore diameter of 0.8 nm or less out of the total pore volume of pores with a pore diameter in the range of 0 to 2.0 nm It is characterized by a pore volume ratio of 85% or more.

In addition, as an example, the activated carbon for water treatment has a total pore volume of 0.300 cc/g or more with a pore diameter in the range of 1 to 100 nm in pore analysis by the DH method, and the pore volume by the MP method is In the analysis, the total pore volume of pores with a pore diameter ranging from 0 to 2 nm is characterized as 0.340 cc/g or more.

Additionally, as an example, the activated carbon for water treatment preferably has an average particle diameter of 100 to 600 ㎛, and more specifically, 200 to 500 ㎛.

Additionally, as an example, the activated carbon for water treatment is characterized in that it has a compressive strength of 8 N/bead or more.

In addition, as an example, the activated carbon for water treatment is characterized by a sphericity degree of 80% or more.

In addition, a filter for water treatment according to another embodiment of the present invention is characterized by including the activated carbon for water treatment.

Additionally, in one embodiment, the water treatment filter is characterized in that it does not include a binder.

In addition, as an example, the water treatment filter is characterized by a chloroform removal life of 1,900 L or more as measured by Measurement Method 1 below.

[Measurement method 1]

A solution in which chloroform (CHCl ₃ ) was added dropwise to distilled water to a concentration of 0.25 mg/L was passed through a water treatment filter filled with 60 g of activated carbon at a pressure of 1.0 kgf/cm ² , and purge and trap and gas were applied to the permeate. Chloroform concentration was analyzed by chromatography-mass spectrometry. Permeate water is collected and analyzed in units of 50 L, and the flow rate passed until the chloroform removal rate is less than 80% is taken as the removal life.

The present invention relates to the specific surface area and pore volume of activated carbon for water treatment, with a BET specific surface area of 900 to 1,300 m ² /g, and in pore analysis by the DH method, the total pore volume of pores with a pore diameter in the range of 1 to 100 nm. The ratio of the pore volume of pores with a pore diameter of 2.0 nm or less is 80% or more, and in pore analysis by the MP method, pores with a pore diameter of 0.8 nm or less out of the total pore volume of pores with a pore diameter in the range of 0 to 2.0 nm By providing activated carbon for water treatment and a filter for water treatment made of activated carbon with a pore volume ratio of 85% or more, there is an effect of improving the removal performance of low-molecular-weight organic chlorine compounds through appropriate control of BET specific surface area and pore volume. there is.

In addition, when the activated carbon for water treatment according to the present invention has an additional sphericity of 80% or more, not only can the water purification performance be improved, but also the compressive strength and abrasion resistance are improved, so that the activated carbon generated by friction during the water purification process can be reduced. Abrasion is suppressed, which has the effect of eliminating the need for a binder or separate adsorbent to prevent activated carbon dust during filter manufacturing.

Figure 1 is a graph showing the chloroform adsorption performance using activated carbon for water treatment according to an embodiment of the present invention.

Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as commonly understood by a person skilled in the art to which the present invention pertains. In general, the nomenclature used herein is well known and commonly used in the art.

Throughout this specification, when a part “includes” a certain component, this means that it may further include other components rather than excluding other components, unless specifically stated to the contrary.

The present invention relates to activated carbon for water treatment having an activated carbon specific surface area and pore structure to improve the adsorption performance of low molecular compounds such as chloroform as an adsorbent for water treatment, and a water treatment filter containing the same.

Activated carbon can be obtained by carbonizing various raw materials such as wood (waste wood, thinning wood, sawdust), coffee bean residue, raw materials derived from natural products such as coconut shells, tree bark, and fruit, petrochemical by-products, and/or polymer resins. The raw material for activated carbon is not limited to this, and any material or method that can produce activated carbon can be used.

Activated carbon for water treatment

The activated carbon for water treatment according to the present invention preferably has a BET (Brunauer, Emmett & Teller method) specific surface area of 900 to 1,300 m ² /g, and more preferably 950 to 1,200 m ² /g.

If the BET specific surface area of activated carbon for water treatment is less than 900 m ² /g, the pore volume becomes low and there is a problem of not obtaining sufficient adsorption amount, and if the BET specific surface area of activated carbon for water treatment is more than 1,300 m ² /g, adsorption occurs. Performance can be improved, but there is a problem that the pore diameter is greatly expanded and the removal performance of low molecular compounds is reduced.

Additionally, in the pore distribution of activated carbon, the adsorption efficiency of the adsorption target varies depending on what diameter and how many pores exist. It is believed to be mainly affected by the size of the molecular species to be adsorbed, and it is very important to appropriately control the pore distribution of activated carbon when improving the removal performance of low-molecular-weight organic chlorine compounds such as chloroform compared to existing activated carbon for water purifiers. .

The activated carbon for water treatment according to the present invention has a ratio of the pore volume of pores with a pore diameter of 2 nm or less to the total pore volume of pores with a pore diameter of 1 to 100 nm in pore analysis by the DH method (Dollimore-Heal method). It is preferable that it is 80% or more, more preferably 87% or more, and even more preferably 93% or more.

At this time, in pore analysis by the DH method, it is preferable that the total pore volume of pores with a pore diameter in the range of 1 to 100 nm is 0.300 cc/g or more. If the pore volume is less than 0.300 cc/g, it is not suitable because the pore volume and pore diameter for removing chloroform are not formed.

The DH method is generally used to analyze pores with a diameter of 2.0 nm to 50.0 nm because it can relatively easily analyze the distribution of mesopore pores with a diameter of that diameter. By repeatedly specifying the pore volume with a pore diameter of 2.0 nm or less, activated carbon can be designed with a wide range of adsorption targets in addition to molecular species in the low molecular weight region.

In pore analysis by the DH method, when the pore volume ratio of pores with a pore diameter of 2.0 nm or less out of the total pore volume of pores with a pore diameter in the range of 1 to 100 nm is less than 80%, the removal performance of low molecular weight organic chlorine compounds such as chloroform This decreases significantly, and the adsorption capacity for adsorption targets other than the small molecule adsorption target also decreases.

In addition, the activated carbon for water treatment according to the present invention has a ratio of the pore volume of pores with a pore diameter of 0.8 nm or less to the total pore volume of pores with a pore diameter of 0 to 2.0 nm in pore analysis by the MP method (Micropore method). It is preferable that it is 85% or more, more preferably 87% or more, and even more preferably 93% or more.

At this time, in pore analysis by the MP method, it is preferable that the total pore volume of pores with a pore diameter in the range of 0 to 2 nm is 0.340 cc/g or more. If it is less than 0.340 cc/g, it is not suitable for the same reason as the DH method pore volume.

The MP method is generally used in the analysis of pores with a diameter of 2.0 nm or less because it can relatively easily analyze the distribution of micropores with a diameter of 2.0 nm or less. Pores with a pore diameter of 0.8 nm or less are involved in the adsorption and filtration of molecular species in the low molecular weight region, such as chloroform. Therefore, by maintaining the volume of pores with a pore diameter of 0.8 nm or less in the total pore volume at a certain number or more, the filtration performance of the low-molecular-weight organic chlorine-based compound targeted by the present invention can be further improved.

In pore analysis by the MP method, when the pore volume ratio of pores with a pore diameter of 0.8 nm or less out of the total pore volume of pores with a pore diameter in the range of 0 to 2.0 nm is less than 85%, low molecular weight organic chlorine compounds such as chloroform are removed. Performance deteriorates significantly.

In addition, the activated carbon for water treatment according to the present invention preferably has a compressive strength of 8 N/bead or more, and more preferably 10 N/bead or more. Specifically, if the compressive strength is more than 8 N/Bead, damage due to water pressure does not occur when using the filter after manufacturing, and wear resistance is also improved. On the other hand, if the compressive strength is less than 8 N/Bead, activated carbon is damaged by friction during the water purification process. Since it can break and generate dust and there is a problem of performance deterioration due to channeling phenomenon, it is desirable to have a compressive strength of 8 N/Bead or more.

In addition, in the present invention, the term "average particle size" refers to the particle size cumulative diagram of activated carbon using a particle size distribution measuring device (Accusizer 780A, Particle Sizing Systems), and the particle size of activated carbon at 50% of the cumulative point is referred to as the average particle size (D50). It is said that The term "D50" refers to the diameter (of particles) at which 50% by volume of the particles have a lower diameter as measured by dry laser particle sizing technology, also known as laser diffraction particle size measurement.

The average particle size of activated carbon can also affect the performance of water treatment filters. Specifically, the average particle diameter of the activated carbon according to the present invention is preferably 100 to 600 ㎛, more specifically 200 to 500 ㎛.

If the average particle size of activated carbon is too small, there is a disadvantage in that the differential pressure is high in the water purifier, and if the average particle size is too large, the contact area becomes small and the residual chlorine removal performance decreases. Therefore, it is preferable that the average particle diameter of activated carbon is 100 to 600 ㎛.

In addition, the activated carbon for water treatment according to the present invention can further improve water purification performance by additionally setting the degree of sphericity to preferably 80% or more, more preferably 85% or more, and even more preferably 90% or more.

The ‘degree of sphericity’ refers to the value obtained according to Equation 1 below.

[Equation 1]

Sphericity (%): minor axis length (a) / major axis length (b) × 100 (%)

At this time, the term 'spherical' does not mean a sphere in the mathematical sense, but means that the three-dimensional appearance of activated carbon has a round shape like a ball. Activated carbon is made up of fine particles, and these fine particles contain pores that form on its surface and extend to its interior.

As described above, the activated carbon for water treatment according to the present invention satisfies a sphericity level of 80% or more, making it possible to manufacture a filter for water treatment without a binder.

In other words, the filter for water treatment according to the present invention not only does not contain any binder, but also contains a binder to the extent that dust is not generated for the purpose of substantially avoiding the present invention. there is.

Specifically, when activated carbon is used in powder form, there is a risk that activated carbon dust may be discharged along with the purified water during the water purification process, and when used in granular form, as the particles are worn during the water purification process, they break down and become like powdered activated carbon. It generates dust and may be discharged together with purified water.

Accordingly, the present invention can solve the above problem by ensuring that the water treatment filter contains activated carbon with a sphericity of 80% or more. Specifically, when the degree of spheroidization of the activated carbon is 80% or more, not only can water purification performance be improved, but also compressive strength and abrasion resistance are improved, thereby suppressing wear of the activated carbon caused by friction during the water purification process, preventing activated carbon dust. It has the advantage of not requiring a binder or separate adsorbent.

On the other hand, when a water treatment filter is made of activated carbon and has a sphericity of less than 80%, the density as a filter filler is reduced compared to a case with a sphericity of 80% or more, resulting in differential pressure and channeling phenomenon, which reduces water purification performance. This is reduced, and since the degree of sphericity is low and the uniformity of the particles is not sufficiently improved, it has low compressive strength and abrasion resistance, which may lead to the problem of wear of the activated carbon due to friction during the water purification process and subsequent dust generation. . Therefore, it is preferable that the degree of sphericity of the activated carbon is 80% or more.

Activated carbon manufacturing method for water treatment

The method for producing activated carbon for water treatment according to an embodiment of the present invention is as follows.

A method for producing activated carbon for water treatment according to an embodiment of the present invention includes a first step of producing a furan resin; And a second step of carbonizing the furan resin and then activating it to produce activated carbon.

In the present invention, the first step is a step of producing a furan resin by adding a protective colloid to a reactant consisting of furfuryl alcohol, a cross-linking agent, water, and a catalyst, raising the temperature, and curing the reactant. In detail, the first temperature increase of the reactant is performed. Afterwards, a protective colloid is added and the temperature is raised a second time to harden to produce a furan resin.

In the present invention, the term “part by weight” may mean the ratio of weight between each component unless otherwise specified.

In the present invention, the reactant may be composed of 100 parts by weight of furfuryl alcohol, 80 to 130 parts by weight of a crosslinking agent, 100 to 300 parts by weight of water, and 1 to 4 parts by weight of a catalyst based on 100 parts by weight of furfuryl alcohol. It is not limited.

Specifically, the furfuryl alcohol has the following chemical structure and is named furan-2-ylmethanol.

[constitutional formula]

In the present invention, the reactant may include 80 to 130 parts by weight of a crosslinking agent based on 100 parts by weight of the furfuryl alcohol.

Specifically, if the cross-linking agent is included in less than 80 parts by weight, the surface of the furan resin may be uneven and wear may occur, and if it exceeds 130 parts by weight, there is a problem that the compressive strength of the activated carbon is lowered, so the cross-linking agent is 100 parts by weight of furfuryl alcohol. It is preferably contained in an amount of 80 to 130 parts by weight.

Specifically, the type of the crosslinking agent is not limited to a specific one, but may be formalin, paraformaldehyde, trioxane, tetraoxane, and acetal, but is not limited thereto.

In the present invention, the reactant may include 100 to 300 parts by weight of water based on 100 parts by weight of furfuryl alcohol.

Specifically, in the above reactant, if the content of water is less than 100 parts by weight, the reactant is formed into an egg shape or lump, and if the content of water is more than 300 parts by weight, the reaction time is prolonged, making it unsuitable for synthesis, so water is used as furfuryl alcohol. It is preferably included in 100 to 300 parts by weight based on 100 parts by weight.

In the present invention, the reactant may contain 1 to 4 parts by weight based on 100 parts by weight of furfuryl alcohol.

Specifically, in the above reactant, the catalyst is added to control the reactivity by adjusting the pH of the reactant mixed with furfuryl alcohol and water to 1 to 5, preferably pH 2 to 3, and an acid catalyst is preferred. .

Specifically, if the catalyst is included in less than 1 part by weight, the reaction does not proceed or curing does not occur, and if it is included in more than 4 parts by weight, the reaction proceeds rapidly, causing particles to form in lumps or making it difficult to obtain the desired particle shape. Therefore, it is preferable that the catalyst is included in an amount of 1 to 4 parts by weight based on 100 parts by weight of furfuryl alcohol. Specifically, the acid catalyst is not limited to a specific material, but may include inorganic acids such as sulfuric acid, hydrochloric acid, nitric acid, phosphorous acid, and phosphoric acid, decylbenzenesulfonic acid, dodecylbenzenesulfonic acid, lactic acid, maleic acid, malonic acid, malic acid, methanesulfonic acid, Benzenesulfonic acid, benzoic acid, salicylic acid, sulfanilic acid, citric acid, acetic acid, ascorbic acid, oxalic acid, octadecylbenzenesulfonic acid, tartaric acid, tetradecyl benzenesulfonic acid, trifluoroacetic acid, p-toluenesulfonic acid, phenolsulfonic acid, fumaric acid, propionic acid, pyruvic acid and hexadecyl acid. It may be one or more selected from decylbenzenesulfonic acid, and is preferably dodecylbenzenesulfonic acid, but is not limited thereto.

In the present invention, the reactant may be first heated to a temperature of 50 to 100° C., but is not limited thereto. Specifically, if the first temperature increase temperature of the reactant is less than 50 ℃, the reaction time is prolonged or the reaction does not proceed, and if it exceeds 100 ℃, the size of the generated particles is not controlled and lumps are generated, so the reactant is heated to 50 ℃. It is preferable that the temperature is first raised from 100°C to 100°C.

In addition, a furan resin can be produced by first raising the temperature of the reactant, adding a protective colloid to the reactant, and curing it by raising the temperature a second time to a higher temperature than the first temperature rise.

In the present invention, the term "protective colloid" refers to one that acts on the surface during the dispersion of particles to delay aggregation, and may be added in an amount of 0.01 to 0.3 parts by weight per 100 parts by weight of furfuryl alcohol, and is limited thereto. That is not the case.

Specifically, when the protective colloid is added in less than 0.01 parts by weight relative to 100 parts by weight of furfuryl alcohol, the reaction time is prolonged or spherical particles are not formed, and when added in excess of 0.3 parts by weight, small particles are formed. Since it is manufactured in powder form, it is preferable that the protective colloid is included in an amount of 0.01 to 0.3 parts by weight based on 100 parts by weight of furfuryl alcohol.

In the present invention, the protective colloid is at least one selected from the group consisting of methylcellulose, partially hydrolyzed polyvinyl alcohol, gum arabic, and hydroxyethylcellulose, preferably gum arabic, but is not limited thereto. .

In the present invention, the secondary temperature increase is performed at 60 to 120° C., but is not limited thereto. Specifically, if the secondary temperature increase temperature is less than 60 ℃, the curing time becomes longer or the curing does not proceed, making it impossible to obtain the desired particle shape, and if it exceeds 120 ℃, the furan resin melts and forms egg-shaped particles or lumps. It is preferable that the second temperature increase is performed at 60 to 120°C, and specifically, it is more preferable to perform the second temperature increase at 80 to 100°C.

Additionally, during the first and second temperature increases, stirring may be performed at 200 to 300 rpm. In this case, a spherical furan resin with spheroidization of more than 80% and high compressive strength can be produced.

The furan resin cured by the second temperature increase is cooled and then washed and dried. The cooling, washing, and drying may be performed by conventionally known methods and are not particularly limited.

In the present invention, the second step is to carbonize the furan resin and then activate it to produce activated carbon. Activated carbon can be produced by conventionally known carbonization and activation methods.

Specifically, the carbonization and activation method of the prepared furan resin is not limited, but preferably, the prepared furan resin is carbonized at 400 to 600 ° C. for 1 to 2 hours, and then at 800 to 1000 ° C. for 30 minutes to 150 minutes. It can be manufactured by activating with water vapor, but is not limited to this.

If carbonization is performed below 400 ℃, impurities in the furan resin may not be removed, which may interfere with pore formation during activation. If carbonization is performed below 600 ℃, the produced furan resin may break into particles due to heat shrinkage. Carbonization in the second step is preferably carried out at a temperature of 400 to 600°C, and specifically, 400 to 500°C.

If activation is performed below 800 ℃, pores do not form on the surface and inside of the activated carbon, so it does not show water treatment performance. If activation is performed at a temperature exceeding 1000 ℃, the compressive strength decreases and 2nm decreases due to overactivation of the activated carbon surface. Since water treatment performance may decrease due to a decrease in the pore volume ratio, the activation in the second step is preferably performed at a temperature of 800 to 1000 ° C., and specifically, 800 to 900 ° C.

The activated carbon for water treatment produced by the production method according to the present invention has a BET specific surface area of 900 to 1,300 m ² /g, and in pore analysis by the DH method, the total pore diameter is in the range of 1 to 100 nm. The ratio of the pore volume of pores with a pore diameter of 2.0 nm or less in the pore volume is more than 80%, and in pore analysis by the MP method, the pore diameter is 0.8 nm out of the total pore volume of pores with a pore diameter in the range of 0 to 2.0 nm. The pore volume ratio of the pores below is 85% or more, the average particle diameter is 100 to 600 ㎛, and the compressive strength is 8 N/bead or more. Additionally, the degree of sphericity may be 80% or more.

Filter for water treatment

A filter for water treatment according to another embodiment of the present invention includes the above-described activated carbon for water treatment.

In addition, as described above, the water treatment filter according to the present invention is characterized in that it does not contain a binder or contains only a binder that does not generate dust.

In addition, the water treatment filter according to the present invention has a chloroform removal life of 1,900 L or more, preferably 2,100 L or more, more preferably 2,300 L or more, and even more preferably 2,500 L, as measured by Measurement Method 1 below. It is characterized by the above.

[Measurement method 1]

A solution in which chloroform (CHCl ₃ ) was added dropwise to distilled water to a concentration of 0.25 mg/L was passed through a water treatment filter filled with 60 g of activated carbon at a pressure of 1.0 kgf/cm ² , and purge and trap and gas were applied to the permeate. Chloroform concentration was analyzed through chromatography-mass spectrometry. Permeated water was collected and analyzed in units of 50 L, and the flow rate passed until the chloroform removal rate was less than 80% was expressed as the removal life.

The method of measuring the chloroform removal rate was carried out by referring to the standard specifications of water purifiers and the notice on designation of inspection agencies (Ministry of Environment Notice No. 2021-157, August 3, 2021).

For reference, the water treatment filter of the present invention is a filter case filled with activated carbon, and the material, structure, and components of the filter case are not known to those skilled in the art. Since this is well-known, detailed description thereof will be omitted.

In addition, information known to those skilled in the art regarding the material, structure, and components of the filter case is incorporated into the content of the present invention.

Hereinafter, the adsorption performance of activated carbon for water treatment according to an embodiment of the present invention will be described in more detail through examples.

<Examples and Comparative Examples>

<Example 1>

After nitrogen gas (N ₂ ) was adjusted to a flow rate of 1,000 cc/min, 200 g of dried furan resin was flowed into an electric furnace reactor filled with it. The reactor was carbonized by raising the temperature from room temperature at a rate of 10°C/min to 470°C and maintaining it for 60 minutes (holding time).

Afterwards, for activation, the temperature was raised to 870°C at a rate of 10°C/mim and maintained for 30 minutes (maintenance time) using water vapor.

<Example 2>

Spherical activated carbon was prepared in the same manner as in Example 1, except that the activation time was set to 60 minutes.

<Example 3>

Spherical activated carbon was prepared in the same manner as in Example 1, except that the activation time was set to 100 minutes.

<Example 4>

Spherical activated carbon was prepared in the same manner as in Example 1, except that the activation time was set to 120 minutes.

<Comparative Example 1>

Activated carbon was prepared in the same manner as Example 1, except that the activation time was set to 10 minutes.

<Comparative Example 2>

Activated carbon was prepared in the same manner as Example 1, except that the activation time was set to 20 minutes.

<Comparative Example 3>

Activated carbon was prepared in the same manner as in Example 1, except that the activation temperature was 930°C and the activation retention time was 120 to 180 minutes.

<Comparative Example 4>

Activated carbon was prepared in the same manner as in Example 1, except that the activation temperature was 950°C and the activation retention time was 120 210 minutes.

The BET specific surface area and pore volume of the activated carbon prepared according to Examples 1 to 4 and Comparative Examples 1 to 4 and the pore volume according to the DH method and MP method were measured using the following methods, and the results are shown in Table 1 below.

The BET specific surface area was determined by measuring the nitrogen adsorption isotherm at 77K using TriStar 3020 from Micromeritics and using the BET method (Brunauer, Emmett & Teller method).

The pore volume according to the DH method (Dollimore-Heal method) and the pore volume according to the MP method (Micropore method) were measured by nitrogen adsorption at 77K using TriStar 3020 from Micromeritics.

<Experimental example>

Chloroform was removed using the activated carbon prepared according to Examples 1 to 4 and Comparative Examples 1 to 4, referring to the standard specifications and inspection agency designation notice for water purifiers (Ministry of Environment Notice No. 2021-157, Aug. 3, 2021). The removal rate (%) according to life (L) and water flow rate was measured, and these are shown in Table 1 and Figure 1 below.

division Example 1 Example 2 Example 3 Example 4 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 BET specific surface area (m2/g) 912 1,043 1,121 1,283 734 821 1,415 1,657 DH method Total pore volume (cc/g) 0.305 0.382 0.451 0.494 0.123 0.144 0.511 0.533 Pore volume with pore diameter less than 2.0 nm (cc/g, 1 ~ 100 nm) 0.253 0.332 0.410 0.464 0.087 0.109 0.368 0.309 Proportion of pore volume with pore diameter of 2.0 nm or less (%) 83 87 91 94 71 76 72 58 MP Act Total pore volume (cc/g, 0 ~ 2.0 nm)) 0.392 0.424 0.461 0.484 0.267 0.288 0.322 0.413 Pore volume with pore diameter of 0.8 nm or less (cc/g) 0.341 0.369 0.420 0.455 0.221 0.245 0.203 0.215 Pore volume ratio (%) with pore diameter less than 0.8 nm 87 87 91 94 83 85 63 52 Chloroform removal life (L) 1,950 2,100 2,350 2,500 1,200 1,250 1,400 1,550

As shown in Table 1 and Figure 1, as a result of comparing the activated carbon of the example according to the present invention and the activated carbon of the comparative example,

Within a BET specific surface area of 900 to 1,300 m ² /g, the ratio of pore volumes of 2 nm or less among the pore volumes in the 1 to 100 nm range in pore analysis by the DH method is more than 80%, and in pore analysis by the MP method, Activated carbon according to Examples 1 to 4, in which the pore volume ratio of 0.8 nm or less among the pore volumes in the range of 0 to 2.0 nm satisfies 85% or more, removes chloroform better than the comparative examples that do not partially or fully satisfy the above physical property range. Lifespan was found to be significantly higher.

In addition, in terms of chloroform removal rate according to water flow rate, the activated carbon according to Examples 1 to 4 according to the present invention was found to maintain high chloroform removal performance even at a much higher water flow rate than the comparative examples.

If the BET specific surface area is less than 900 m ² /g, chloroform removal performance is reduced due to insufficient pore volume formation by the DH method and MP method.

In addition, when the BET specific surface area is greater than 1,300 m ² /g, the pore diameter increases, and the pore volume ratio of 2.0 nm or less by the DH method is greatly reduced, greatly reducing the chloroform removal performance, and the pore volume ratio of 0.8 nm by the MP method is also greatly reduced. Due to the above-mentioned reasons, the chloroform removal performance is significantly reduced.

The present invention has been described above with reference to the embodiments shown in the accompanying drawings, but these are merely illustrative, and various modifications and other equivalent embodiments can be made by those skilled in the art. You will understand that Therefore, the scope of technical protection of the present invention should be determined by the claims below.

Claims (8)

The BET specific surface area is 900 to 1,300 m ² /g,
In pore analysis by the DH method, the total pore volume of pores with a pore diameter ranging from 1 to 100 nm is greater than 0.300 cc/g, and the pore diameter of the total pore volume of pores with a pore diameter ranging from 1 to 100 nm is 2.0 The ratio of the pore volume of pores smaller than nm is 80% or more,
In pore analysis by the MP method, the total pore volume of pores with a pore diameter ranging from 0 to 2.0 nm is 0.340 cc/g or more, and the pore diameter of the total pore volume of pores with a pore diameter ranging from 0 to 2.0 nm is 0.8. Activated carbon for water treatment, characterized in that the ratio of pore volume of pores of nm or less is 85% or more.
delete According to paragraph 1,
The activated carbon for water treatment is,
Activated carbon for water treatment, characterized in that the average particle diameter is 100 to 600 ㎛.
According to paragraph 1,
The activated carbon for water treatment is,
Activated carbon for water treatment, characterized in that it has a compressive strength of 8 N/bead or more.
According to paragraph 1,
The activated carbon for water treatment is,
Activated carbon for water treatment, characterized by a sphericity of 80% or more.
A filter for water treatment, characterized in that it contains the activated carbon for water treatment according to any one of claims 1, 3 to 5.
According to clause 6,
The water treatment filter is,
A filter for water treatment, characterized in that it does not contain a binder.
According to clause 6,
The water treatment filter is,
A water treatment filter characterized by a chloroform removal life of 1,900 L or more as measured by measurement method 1 below.
[Measurement method 1]
A solution in which chloroform (CHCl ₃ ) was added dropwise to distilled water to a concentration of 0.25 mg/L was passed through a water treatment filter filled with 60 g of activated carbon at a pressure of 1.0 kgf/cm ² , and purge and trap and gas were applied to the permeate. Chloroform concentration was analyzed by chromatography-mass spectrometry. Permeated water is collected and analyzed in 50 L units, and the flow rate passed until the chloroform removal rate is less than 80% is taken as the removal life.