KR101111642B1 - Manufacturing method of spherical form activated carbon - Google Patents

Abstract

The present invention relates to a method for producing spherical activated carbon having a low pressure loss and having a constant size and strength. (1) 100 parts by weight of a mixture of carbonaceous powder and phenol resin powder selected from the group consisting of charcoal, activated carbon or a mixture thereof A mixing step of preparing a molding mixture by mixing 20 to 45 parts by weight of lower alcohols having 1 to 4 carbon atoms; (2) a primary molding step of molding the molding mixture obtained in the mixing step into pellets (short cylindrical molded body); (3) 80 to 90 while stirring the pellets obtained in the first molding step at a rate of 50 times / minute on a sieve having a scale of 30 to 50 mesh. A secondary molding step of forming a spherical body by applying hot air at a temperature of ℃; (4) carbonizing the spheroid obtained in the secondary molding step by circulating carbon gas at a temperature of 600 to 800 ° C. for 100 to 150 minutes at a circulation rate of 100 to 200 ml / min; And (5) activating the spheroid through the carbonization step by circulating carbon dioxide gas at a circulation rate of 100 to 200 ml / min for 100 to 150 minutes at a temperature of 750 to 950 ° C .; It is done.

Carbon Powder, Activated Carbon, Carbonization, Activation, Binder, Spherical, Molding, Alcohol

Description

Manufacturing method of spherical activated carbon {Manufacturing method of spherical form activated carbon}

The present invention relates to a method for producing spherical activated carbon, and more particularly, to a method for producing spherical activated carbon having low pressure loss and having a constant size and strength.

Commercially available adsorbents include activated carbon, zeolites, and alumina. Activated carbon is an adsorbent that causes physical adsorption of fine mesh plane structure and has inherent heat and chemical resistance of carbon materials, and mostly has a diameter of a micropore size distribution of 2 nm and adsorbs nonpolar materials. Products having a specific surface area of about 800 to 2,000 m 2 / g are widely used. Zeolite is a crystalline aluminosilicate, which has a pore diameter (0.3 to 1 nm) of a certain size depending on the crystal form, and shows the effect of molecular sieves. It is used for adsorption of polar substances such as water. In this way, activated carbon is a lipophilic adsorbent, whereas zeolite is a hydrophilic adsorbent. Thus, by using a mixture of activated carbon and zeolite, mutual adsorption power can be complemented to express a complex function. In addition, the use of a mixture of other adsorbents such as alumina can provide additional complex functions. However, since activated carbon, zeolite, and alumina have different specific gravity, porosity, and surface properties, it is necessary to maintain a fixed form by using a binder to maintain a uniformly mixed state. Pitch, water glass, polyvinyl alcohol, etc. are used as a binder of a powder adsorbent.

The development of the manufacturing industry, the increase of fuel consumption, etc., the generation of various harmful gases to increase and improve the environmental regulation day by day, and the need to remove it is gradually increasing. In addition, as the production of high-precision products and the standard of cultural life increase, the demand for high-functional adsorbents with low flammability even at relatively high temperatures such as air cleaners, semiconductor processes, precision automation processes, various air conditioners, and exhaust gas removal increases rapidly. have. Domestic activated carbon related industry is insufficient to mass-produce high-quality products due to its small size and weakness of technology, and a large amount of low-grade products manufactured in China are imported. In addition, in the case of high-performance products, there is a significant impact on the industrial base by not providing reliable products. High-performance adsorption materials, on the other hand, have a low performance of domestic products and are almost entirely dependent on imports from developed countries such as the US, Japan, and Europe. In order to overcome this difficult situation, the production of high-performance filter materials for removal of air purifiers, precision industrial odors, harmful gases, pathogens, etc. is strongly demanded to increase the business feasibility through product diversification. Recognizing that this is a situation that is playing a vital role in the development of it. Effective and continuous removal of odors, harmful gases and pathogens is difficult to realize with activated carbon alone, and it is adsorbed and decomposed and removed to an acceptable level through the combination of high-performance spherical activated carbons with high surface area and fine pores. It is possible.

In particular, in the case of highly functional adsorbents with low environmental ignition and low ignition in producing high-quality electrical and electronic devices, (A) the increase in energy demand and the increase in the demand for clean products every year, (B) the deepening of environmental pollution, ( C) It is difficult to make efficient use of enormous facility investment, (D) It needs to develop mass production system of functional composite spherical products, (E) Green growth and sustainable eco-friendly technology and (F) Securing clean energy materials and practical technology The demand is increasing.

The domestic market is classified as an air pollution prevention facility, growing by an average of 11 trillion won in 2005, with an average annual growth rate of 11%. The domestic market size of volatile organic compounds (VOCs) emission treatment equipment is about 120 billion won, and the double adsorbent is about 10%. It is estimated to be about 12 billion won. Adsorbents for semiconductor clean rooms are estimated to be over 30 billion and more than 20 billion for air cleaners, and show a high growth rate of more than 5% a year due to increasing demand for health and environmental maintenance. Advanced companies in adsorbents include companies such as Calgon of the United States, Norrit of the Netherlands, and Kuraray of Japan. These companies are aiming for economies of scale with manufacturing, research, and sales bases in each region of the world to secure competitiveness in resources, human resources, and sales, and continue to invest heavily in research and development to develop high-performance, high-value-added products. With a focus on production and sales, the company continues to develop, maintaining a 60% market share and high business viability even in the offensive of low-cost goods in Asian countries. On the other hand, due to the development of precision industry such as semiconductors and the increase of regulations on prevention of environmental pollution, the demand for high-performance adsorption materials with excellent removal ability for various harmful gases such as air conditioners, air cleaners, gas masks, and vehicles in the clean room of manufacturing processes is rapidly increasing. It is increasing. Therefore, not only the above companies, but also odor and harmful gas from all over the world such as Japan's Canon, Mitsui Mining, Ebara Manufacturing, Nippon Oxygen and Germany's Babcock Anragen We are researching the removal technology. The technologies include combustion technology, oxidizer or catalyst technology, ozone technology, photocatalyst and UV light technology, inorganic microorganism technology, adsorbents such as activated carbon and zeolite. Various techniques are used.

Major markets and countries or regions can be classified into the United States, Europe, Japan, and India.

-Korean market size: 70 billion won (2007), 85 billion won (2011, average annual growth rate of 5%)

-Global market: 40 times larger than Korean market (KRW 280 billion (2007), KRW 430 billion (2011))

* Reference: Comprehensive Environmental Technology Development Plan (2003-2007), Carbon Adsorbent Workshop of the Korea Carbon Society, October 2007

Until now, several methods for producing an activated carbon molded article using a phenolaldehyde-based resin as a binder have been known. In the method described in Japanese Patent Application Laid-open No. 49-115110, activated carbon molded bodies are produced by adding a phenolaldehyde-based resin to carbon materials such as charcoal and extruding them, followed by carbonization or reactivation after carbonization. Surface area is 300 m <2> / g or less, and it is obtained by reactivation that the specific surface area is 1100300 m <2> / g. Japanese Patent Laid-Open Publication No. 57-27130 uses synthetic resin fibers such as phenolic resin and melamine resin for carbon materials, and Japanese Patent Laid-Open No. 3-42039 discloses a phenolic resin binder with powdered activated carbon. After shaping by mixing with carbonization, carbonization and reactivation are performed.

However, since the activating step is required after molding, the mechanical strength of the molded body is lowered, and the cost is high, which is not industrially preferable.

Japanese Patent Laid-Open Publication No. 55-167118 and Japanese Patent Laid-Open Publication No. Hei 7-207119 disclose a method for producing an activated carbon molded body by molding, drying and curing the activated carbon using a liquid phenolaldehyde-based resin at room temperature as a binder. It is described. However, in this method, activation is not performed and since the binder component blocks the pores of the activated carbon, there is a problem that the adsorption capacity of the activated carbon is significantly lowered.

The present invention has been made in order to solve the problems of the prior art as described above is to improve the production method of the spherical activated carbon having a low pressure loss, a certain size and strength.

Method for producing spherical activated carbon for achieving the object of the present invention as described above (1) carbon number 1 based on 100 parts by weight of a mixture of carbonaceous powder and phenol resin powder selected from the group consisting of charcoal, activated carbon or a mixture thereof Mixing step of preparing a molding mixture by mixing 20 to 45 parts by weight of the lower alcohol of 4 to 4; (2) a primary molding step of molding the molding mixture obtained in the mixing step into pellets (molded article of short cylindrical shape); (3) 80 to 90 while stirring the pellets obtained in the first molding step at a rate of 50 times / minute on a sieve having a scale of 30 to 50 mesh. A secondary molding step of forming a spherical body by applying hot air at a temperature of ℃; (4) carbonizing the spheroid obtained in the secondary molding step by circulating carbon gas at a temperature of 600 to 800 ° C. for 100 to 150 minutes at a circulation rate of 100 to 200 ml / min; And (5) activating the spheroid through the carbonization step by circulating carbon dioxide gas at a circulation rate of 100 to 200 ml / min for 100 to 150 minutes at a temperature of 750 to 950 ° C .; It is done.

In the mixing step, the carbonaceous powder may be 100 to 200 mesh carbon powder selected from the group consisting of wood charcoal, keratin shell charcoal, chaff charcoal, charcoal charcoal or a mixture of two or more thereof.

The carbonaceous powder in the mixing step may be a metal salt treatment.

In the mixing step, the mixture of the carbonaceous powder and the phenol resin powder may be formed by mixing 58 to 65 wt% of the carbonaceous powder and 42 to 35 wt% of the phenol resin powder.

The pellets in the first molding step (2-1) supplying the molding mixture obtained in the mixing step on the intermediate mold formed with the molding sphere having a plurality of cylindrical inner spaces; (2-2) the upper mold having a flat bottom surface is moved from the upper side of the middle mold to the middle mold to press the molding mixture on the intermediate mold so that the molding mixture is put into the molding spheres of the intermediate mold and pressurized. Pellet forming step of forming; (2-3) compression molding in the molding spheres of the intermediate mold by moving the lower mold having the outgoing protrusions having the same shape as the molding spheres of the intermediate mold from below the intermediate mold toward the intermediate mold; It may be formed by the withdrawal step; to push out the molding mixture.

After removing the upper mold from the intermediate mold after the pellet forming step, a removing step of removing the unmolded molding mixture remaining on the intermediate mold may be further performed.

The spherical body obtained in the secondary molding step may further comprise a drying step of drying for 7 to 10 hours at a temperature of 100 to 200 ℃ in the activated carbon powder prior to the carbonization step.

The carbonization step may further include a screening step of sieving on a sieve having a scale of 50 to 80 mesh before activating the globular body in the activation step.

According to the present invention, there is provided a method for producing spherical activated carbon having a low pressure loss and having a constant size and strength.

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

As exemplarily shown in FIG. 1, the method for producing spherical activated carbon according to the present invention includes (1) 100 parts by weight of a mixture of carbonaceous powder and phenol resin powder selected from the group consisting of charcoal, activated carbon or a mixture thereof. A mixing step of preparing a molding mixture by mixing 20 to 45 parts by weight of lower alcohols having 1 to 4 carbon atoms; (2) a primary molding step of molding the molding mixture obtained in the mixing step into pellets (short cylindrical molded body); (3) 80 to 90 while stirring the pellets obtained in the first molding step at a rate of 50 times / minute on a sieve having a scale of 30 to 50 mesh. A secondary molding step of forming a spherical body by applying hot air at a temperature of ℃; (4) carbonizing the spheroid obtained in the secondary molding step by circulating carbon gas at a temperature of 600 to 800 ° C. for 100 to 150 minutes at a circulation rate of 100 to 200 ml / min; And (5) activating the spheroid through the carbonization step by circulating carbon dioxide gas at a circulation rate of 100 to 200 ml / min for 100 to 150 minutes at a temperature of 750 to 950 ° C .; It is done.

In the mixing step of (1), the carbonaceous powder may be 100 to 200 mesh carbon powder selected from the group consisting of wood charcoal, keratin fruit shell charcoal, chaff charcoal, charcoal charcoal or a mixture of two or more thereof. However, it will be understood by those skilled in the art that in the manufacturing method according to the present invention, all kinds of organic materials which can be carbonized or carbonized can be used because both the carbonization step and the activation step are included.

The carbonaceous powder in the mixing step may be a metal salt treatment. The metal salt treatment may be carried out by impregnating the carbonaceous powder described above in an aqueous solution of a metal salt having antibacterial properties, and then separating the impregnated carbonaceous powder by filtration or the like and drying. The metal salts having antimicrobial properties include silver nitrate, silver sulfate, silver hydrochloride, silver acetate, copper nitrate, copper sulfate, copper hydrochloride, copper acetate, nickel nitrate, nickel sulfate, nickel hydrochloride, nickel Acetate, copper nitrate, sulfate of nickel, hydrochloride of nickel, acetate of nickel, titanium dioxide or a mixture of two or more thereof. The present invention is not limited by the type of the metal salt used, the concentration of the aqueous solution of the metal salt, etc., any metal salt having antimicrobial properties can be used, and the concentration of the aqueous solution of the metal salt is also desired by those skilled in the art It can be understood that the enemy can be controlled according to the type of carbon powder to be made.

The mixing step of (1) is a step of mixing the components used as the raw material of the spherical activated carbon in the manufacture of the spherical activated carbon according to the present invention with respect to 100 parts by weight of the mixture of the carbonaceous powder as a main ingredient and the phenol resin powder functioning as a binder 20 to 45 parts by weight of lower alcohols having 1 to 4 carbon atoms are mixed to prepare a molding mixture. In the above alcohol is used to impart fluidity to the mixture for shaping the mixture. When the alcohol is used in less than 20 parts by weight with respect to 100 parts by weight of the mixture, there may be a problem that the molding fluid is too low to be molded well, on the contrary, if it exceeds 45 parts by weight, moldability This may not be good and the sphere may be broken and broken.

The primary molding step of (2) consists of molding the molding mixture obtained in the mixing step into pellets (molded articles having short lengths). The primary molding step is a preceding molding step in order to facilitate molding into a spherical shape in the production of spherical activated carbon according to the present invention.

In the secondary molding step (3), the pellets obtained in the primary molding step are stirred for 10 to 20 minutes at a rate of 50 times / minute on a sieve having a scale of 30 to 50 mesh. It forms by spherical body by applying hot air of the temperature of 80-90 degreeC, shaking. The secondary molding step is more specifically (2-1) a supplying step of supplying the molding mixture obtained in the mixing step on the intermediate mold formed with the molding sphere having a plurality of cylindrical inner space (Fig. 2 ( A) and (b) process); (2-2) the upper mold having a flat bottom surface is moved from the upper side of the middle mold to the middle mold to press the molding mixture on the intermediate mold so that the molding mixture is introduced into the molding tools of the intermediate mold. Pellet forming step to be molded (Fig. 2 (c) process); (2-3) compression molding in the molding spheres of the intermediate mold by moving the lower mold having the outgoing protrusions having the same shape as the molding spheres of the intermediate mold from below the intermediate mold toward the intermediate mold; The pellets may be formed by a withdrawal step (step (d) and (e) of FIG. 2) to push out the molding mixture. The upper mold, the middle mold and the lower mold are shown in FIG. 2.

By the secondary molding step, the spherical activated carbon according to the present invention may be formed into a spherical shape, and then spherical activated carbon according to the present invention may be obtained by carbonization and activation. When the size of the scale of the sieve is less than 30 mesh in the above, there may be a problem that the molding of the pellets to be spherical shaped by stirring on the spherical shape is not made well, even if the pellet exceeds 50 mesh There may be a problem that the molding of these spheres is not made well. In addition, when the stirring time is less than 10 minutes, there may be a problem that the pellets that are not sufficiently spherical shape remains, on the contrary, more than 20 minutes is rather a problem that the spherical molded articles tend to be damaged There may be. In addition, when the temperature of the hot air is less than 80 ℃, there may be a problem that the heating effect is lowered, on the contrary, when it exceeds 90 ℃, the phenomena of the phenol resin is hardened quickly to harden spherical form There may be a problem. In addition, after removing the upper mold from the intermediate mold after the pellet forming step, a removing step of removing the unmolded molding mixture remaining on the intermediate mold may be further performed.

The carbonization step of (4) consists of circulating and carbonizing the spherical body obtained in the second molding step at a temperature of 600 to 800 ° C. for 100 to 150 minutes at a circulation rate of 100 to 200 ml / min. Here, when the carbonization temperature is less than 600 ℃ or the carbonization time is less than 100 minutes, there may be a problem that the carbonization is not enough, on the contrary, if the carbonization temperature exceeds 800 ℃ or the carbonization time exceeds 150 minutes There is no problem, but there is no need for excessive carbonization, but rather there may be a problem of wasting energy required for carbonization. In addition, when the circulation rate of the nitrogen gas is less than 100ml / min, there may be a problem that the carbonization is not made well due to the possibility of oxidation during carbonization, on the contrary, if the excess exceeds 200ml / min, No, but there may be a problem of excess waste.

The activation step of (5) consists of activating the spheroid through the carbonization step by circulating carbon dioxide gas at a circulation rate of 100 to 200 ml / min for 100 to 150 minutes at a temperature of 750 to 950 ° C. Here, when the activation temperature is less than 750 ℃ or the activation time is less than 100 minutes, there is a problem that the specific surface area becomes small due to insufficient activation is made, on the contrary, the activation temperature exceeds 950 ℃ Alternatively, if the activation time exceeds 150 minutes, there may be a problem of economic loss. In addition, when the circulation rate of the carbon dioxide gas is less than 100ml / min, there is a problem that the specific surface area becomes small due to insufficient activation, on the contrary, if it exceeds 200ml / min, the problem of economic loss This can be.

In the mixing step, the mixture of the carbonaceous powder and the phenol resin powder may be formed by mixing 58 to 65 wt% of the carbonaceous powder and 42 to 35 wt% of the phenol resin powder. When the phenolic resin powder is more than 42% by weight in the mixture, it is not spherical well, there may be a problem that the spherical shape is easily distorted during the stirring process, on the contrary, when less than 35% by weight, it is also spherical It may not have, and there may be a problem that cracks easily occur in the sphere during stirring.

The spherical body obtained in the secondary molding step may further comprise a drying step of drying for 7 to 10 hours at a temperature of 100 to 200 ℃ in the activated carbon powder prior to the carbonization step. In this drying step, since a large amount of phenol resin is used in the spherical body, the spherical bodies may stick to each other in subsequent processes, and it is preferable to dry the activated carbon powder in order to prevent this. In the drying step, if the drying temperature is less than 100 ℃ or the drying time is less than 7 hours, there may be a problem that the sufficient drying is not made, on the contrary, the drying temperature exceeds 200 ℃ or drying time is If it exceeds 10 hours, there is no particular problem, but there may be a problem of economic loss. Activated carbon powder used to dry the spherical body in the drying step may be recovered and removed to be used again in a drying step or to be used for other purposes.

The method may further include a screening step of sieving the spherical body having undergone the carbonization step on a sieve having a scale of 50 to 80 mesh before activating in the activation step. The sorting step is performed to remove the fine carbon powder. In the case of using a sieve of less than 50 mesh, there may be a problem that the screening is not made due to the spherical body coming out together, on the contrary, when using more than 80 mesh, the derivative will not escape There may be a problem that the screening is not made.

Hereinafter, preferred embodiments and comparative examples of the present invention will be described.

The following examples are intended to illustrate the invention and should not be understood as limiting the scope of the invention.

Preparation of spherical activated carbon according to the present invention is to use activated carbon powder which is not subjected to silver treatment as one group and activated carbon powder which is subjected to silver treatment as another group (by depositing activated carbon powder in silver nitrate solution of 0.01M The process was carried out in the same manner as described below, except that a treated activated carbon powder) was used.

Two types of spherical activated carbon were prepared using an activated carbon powder (Korean, Hanil Greentech, Coal based activated carbon) having a particle size of 100 to 400 mesh in the mixing step. Phenol resin (product made in Gangnam Hwaseong, Korea) was used as a binder used in the manufacturing process. The mixture for molding is 35 parts by weight (65 parts by weight of activated carbon powder), 37 parts by weight (63 parts by weight of activated carbon powder), 40 parts by weight (60 parts by weight of activated carbon powder) and 43 parts by weight (based on activated phenol resin) 57 parts by weight of powder) and a mixture of phenolic resin and activated carbon fine powder evenly mixed to obtain a mixture, and was mixed and kneaded by spraying 25 parts by weight of ethanol based on 100 parts by weight of the mixture.

In the first molding step these mixtures were molded into pellets by molding into molding molds for spheronization as shown in FIG.

In the second molding step, the pellets obtained in the first molding step are placed on a 50 mesh sieve, and stirred in a conventional shaker as shown in FIG. The pellet was spherical shaped by stirring at speed for 15 minutes.

After molding, the activated carbon powder was dried with stirring at 150 ° C. for 8 hours, and the spherical activated carbon prepared as described above was carbonized at 700 ° C. for 2 hours at a circulation rate of 150 ml / min.

After the carbonization in the activation step, these samples were activated for 2 hours at a circulation rate of 150 ml / min using carbon dioxide gas at 950 ° C. At this time, the temperature increase rate in the activation furnace was 10 ° C / min.

The spherical activated carbons obtained above were named as follows.

2 shows spherical activated carbons prepared according to the present invention. (A) is SAC35, (b) is SAC37, (c) is SAC40, and (d) is SAC43, respectively. As shown in Figure 2, according to the content of the phenol resin in the manufacturing process according to the present invention it was confirmed that the appearance before and after the activation shows a number of differences. Referring to Figure 2, after the activation, a large number of pores and cracks were characteristic according to the amount of phenol resin. The small amount of phenolic resin produced many cracks, and the apparent strength was also very weak. As the amount of phenolic resin was increased, the cracks gradually decreased, and spherical particles were well formed. However, in the case of SAC43 having a large amount of resin, moldability was also poor. Visually, it could be seen that the case of SAC40 of FIG.

In addition, the following experiments were performed using the spherical activated carbon according to the present invention as a sample.

Experimental Example 1

Iodine adsorption

0.5 g of a dry sample of average particle diameter of 325 mesh is precisely weighed up to 1 mg in 100 ml of a stoppered Erlenmeyer flask, and 50 ml of N / 10 iodine solution is added accurately, shaken with a shaker for 15 minutes at room temperature, and then put into a 50 ml settling plate. The sample was precipitated using a separator. 10 ml of the supernatant is aliquoted, and titrated with N / 10 sodium thiosulfate solution. When the yellow color of iodine becomes light, 1 ml of 1 weight / vol% starch solution is added as an indicator and the titration is continued to remove the blue color of the iodine starch. As the end point, the number of mg of iodine adsorbed per 1 g of the sample was obtained using Equation 1 below. 12.69 in the following formula 1 is the amount of iodine (mg) corresponding to 1 ml of N / 10 sodium thiosulfate solution.

In general, the iodine adsorption power of granular and finely divided activated carbon ranges from 900 to 1200 mg / g. However, when they are treated with metals or made into structures and spheres, they have been reported to decrease significantly. The results for the iodine adsorption force are shown in FIG. 3. As shown in FIG. 3, the sample before activation showed a significantly lower iodine adsorption capacity than the sample after activation. However, silver-treated spherical activated carbon samples showed slightly higher adsorption compared to untreated fertilizers. This is presumably due to the chemical reactivity by the formation of silver iodide with silver. The sample after activation showed a high adsorption capacity of 750 to 800 mg / g. These pores, which were closed (blocked) by the phenolic resin, are re-formed by reactivation and are considered to exhibit high adsorption capacity. In addition, the higher the content of the phenolic resin was confirmed that the adsorption capacity of iodine gradually decreases.

Experimental Example 2

Nitrogen Specific Surface Area Measurement

In general, low temperature nitrogen surface area measurements are used to measure them by the BET method (specific surface area analysis method according to Stephan B runauer, principles are released Paul E mmett and Edward T eller). The sample was lowered to the temperature of liquid nitrogen at low temperature, and then the adsorption amount of nitrogen gas was measured and converted to specific surface area.

Iodine adsorption and nitrogen adsorption are important parameters that characterize porous materials. These are directly related to gaseous adsorption and pollutant adsorption, and the specific surface area increases with the formation of pores. The results for the nitrogen specific surface area value of the spherical activated carbon are shown in FIG. 4. As shown in FIG. 4, in the case of spherical activated carbon before activation, the specific surface area shows a large change depending on the amount of phenol resin. When the amount of the phenol resin was 35 to 37% by weight, the specific surface area was formed at about 300 m 2 / g before and after the silver treatment. However, 40 to 43% by weight of spherical activated carbon samples showed a specific surface area reduction rate of 50% or more. This fact can be inferred from the relative decrease in the amount of activated carbon and clogging of pores by phenolic resin. Therefore, it was confirmed that the selection of the amount of the binder must be one of the important factors. After activation, it showed a significantly higher specific surface area value consistent with the iodine adsorption capacity. These are also considered to be an increase in specific surface area due to the generation of pores. The results before and after the silver treatment were somewhat different, but unlike the iodine adsorption, there was not much difference. According to the research results, in the case of silver treated activated carbon prepared by treating silver nitrate with activated carbon, the specific surface area tended to decrease gradually according to the amount of silver salt treated. The increase in specific surface area is closely related to the adsorption amount of organic substances and pollutants in the physical adsorption process.

Experimental Example 3

Strength measurement

The strength was measured according to JIS R 7212. The strength measurement was performed using a one-point needle, the instrument used was Instron 4201, the support distance was 30mm / min, the cross head speed (cross head speed) was 0.5mm / min. The diameter of the specimen was measured with spherical particles of about 5 mm, and the strength value was calculated based on Equation 2 below.

Where σ _F is the strength (kg / cm 2), P is the breaking load (kg), L is the support distance (cm), B is the sample width (cm), and D is the sample thickness (cm).

The strength of the ceramic material varies greatly depending on the type of the binder, but in general, the binders used in the carbon material are separated from the carbon by 30 to 40% of the carbonized material when carbonized. In the present invention, a large amount of binder was used because it has a lot of pores in the nature of the raw material. In activated carbon materials, the rearrangement between particles and the mutual bonding between particles are generally poor. As the binder leaves, more pores are left after firing. Such pore structure greatly degrades the mechanical properties due to stress concentration around the pore, and in particular, significantly affects tensile strength. 5 shows the result of the strength intensity of the spherical activated carbon. According to these results, the strength value increased as the amount of phenol resin increased. These results indicate that the amount of binder did not adversely affect the strength. Contrary to expectations, the interfacial bond between the binder and the activated carbon is well maintained to increase the bonding force. As shown in FIG. 2, the amount of binder had a significant effect on binding force and spherical shape. In the case of SAC40, the spherical formability was excellent, and the strength was also the highest. The silver samples of SAC43 showed slightly lower strength values, and this phenomenon is believed to have influenced the strength values by increasing the volatile content of the binder component. However, when spherical activated carbon was prepared using silver treated activated carbon, the strength value was slightly lower. This phenomenon is believed to be related to the silver inhibiting phenomenon in the binding of the phenol resin and activated carbon.

Experimental Example 4

Antibacterial function measurement

In order to measure the biological antimicrobial activity, E. coli , a non-pathogenic bacterium, was selected as a bacterium and measured using a halo test and a count method. The bacteria were incubated at 37 ° C. for 24 hours in a thermo-hygrostat before the developed spherical activated carbon samples were contacted with the test strain. Cultivated non-pathogenic strains were added dropwise by quantifying the specific pathogenic strains of the specific number of the spherical activated carbon samples 2g of each developed spherical activated carbon in 95ml of distilled water. The medium thus prepared was stored while shaking in a constant temperature and humidity chamber at 37 ° C. for 24 hours, and when the non-pathogenic strains lost their activity, the number of bacteria was counted at that time to determine the antimicrobial activity.

The production of activated carbon by metal treatment is one of the representative methods for enhancing the antibacterial function. Activated carbon has little antimicrobial activity, but has fungal affinity, and if contaminated bacteria are used, there is room for secondary pollution. In order to examine the antimicrobial properties, silver-treated activated carbon was treated by applying E. coli as a bacterium to sterilized medium. E. coli from the results showed that the antimicrobial properties by the growth inhibition by the treated silver. The results for the antimicrobial properties are shown in FIG. 6. Most bacteria are made up of proteins and are simple cellular constructs. These cells react with silver ions attached to the edges of carbon. Therefore, bacteria are killed because metal ions can't destroy or self-replicate. In addition, it was confirmed that the antibacterial activity against Salmonella, Listeria, Staphylococcus, Negionella and the like.

In addition, according to the studies studied, few studies have been conducted on the quantitative antimicrobial properties of activated carbon. Figure 7 shows the quantitative results on the antibacterial properties for the prepared spherical activated carbon. Initially, 10 ⁵ CFU / mL (colony forming unit (CFU); colony forming unit) were used. E. coli after spherical activated carbon treatment showed an antibacterial property of 98% or more. In the case of SAC40 according to the present invention, the antimicrobial activity was slightly high, but all four samples showed excellent antimicrobial activity.

Experimental Example 5

Pressure loss

The pressure loss of the material passing through the pipe was measured. The sample stored in the tank was configured by the pump to circulate a pipe having an internal diameter of 27.0 mm and a total length of 12 m. The pressure loss was averaged using an inverted type manometer with a 300mm distance between taps and a mono pump with a maximum capacity of 3.5㎥ / hour (Mohno pump, model: 2NE-20A). Pressure loss was measured while varying the flow rate in the range of 0.25-1.7 m / sec. In general, the pressure drop due to the friction loss along the length of the straight pipe can be obtained by the Hazen-Wiliams formula of Equation 3 below.

Where ΔP is the pressure drop per kilometer of pipe length (kg / cm 2) due to friction loss, Q is the flow rate in the pipe (l / min), d is the inner diameter of the pipe (mm) and C is the roughness of the pipe 120 to be.

When the gas tower line velocity (LV) is the same, the adsorption (deodorization) efficiency increases as the particle size is smaller, but the blowing pressure loss increases, so it is important to select the optimum particle size in consideration of the static pressure of the blower. Atmospheric adsorption towers are quite difficult in mechanical design and installation due to pressure loss. However, spherical activated carbon has more porosity between particles, uniform particles, and less pressure loss. The activated carbon used in the adsorption system should be sufficiently examined for the properties of the material to be treated, and the relationship between the adsorption characteristics of the activated carbon and the pore distribution and the molecular weight distribution of the material to be adsorbed should be examined. In addition, in the case where the concentration of the substance to be adsorbed is high, it is a principle that the activated carbon adsorption treatment is performed after sufficiently reducing it by another treatment method. Most importantly, the selection and use of the most appropriate activated carbon must be carried out according to the purpose of use. Therefore, it is necessary to clarify whether the adsorbed material is mono- or multi-component, and set conditions such as the lifetime and contact time of activated carbon from the equilibrium adsorption and the results of the solution test. In order to solve this problem, spherical activated carbon has the most optimal condition. As a result, usage is also increasing in developed countries. If the formability is not good during the production of spherical activated carbon, the generation of fine powder and debris increases due to the occurrence of cracks and cracks. When using such conventional spherical activated carbon, not only is it a direct cause of pressure loss, but also durability is reduced. According to the present invention, as shown in FIG. 8, when the amount of the binder is small, the pressure loss value is gradually decreased, and in the case of SAC43, it is increasing again. This fact is considered to be closely related to formability. As shown in FIG. 2, in the case of SAC40, moldability was most excellent. In this regard, in the case of SAC40, the pressure loss was the smallest. Silver treated activated carbon showed slightly higher value than untreated activated carbon. As mentioned above, in the case of silver treatment, the pressure value is expected to be large due to the formation of cracks and debris due to the complex effect of volatilization of the dendritic volatiles and nitrate gas components during the heat treatment process. .

The present invention can be used in the manufacturing industry of activated carbon and adsorbents using the activated carbon.

While the invention has been shown and described with reference to certain exemplary embodiments thereof, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention as defined by the appended claims.

1 is a flow chart showing a method for producing spherical activated carbon according to the present invention.

Figure 2 is a photograph of the state of the spherical activated carbon produced according to the present invention.

Figure 3 is a graph showing the results for the iodine adsorption power of spherical activated carbon prepared according to the present invention.

Figure 4 is a graph showing the results for the nitrogen specific surface area of the spherical activated carbon prepared according to the present invention.

5 is a graph showing the result of the strength intensity of the spherical activated carbon prepared according to the present invention.

Figure 6 is a photograph showing the results of the antimicrobial properties of SAC40 among the results for the antimicrobial properties of spherical activated carbon prepared according to the present invention.

Figure 7 is a graph showing the quantitative results on the antibacterial properties of spherical activated carbon prepared according to the present invention.

8 is a graph showing the results for the pressure loss of the spherical activated carbon prepared according to the present invention.

Claims (8)

In the production of spherical activated carbon, (1) a mixing step of preparing a molding mixture by mixing 20 to 45 parts by weight of a lower alcohol having 1 to 4 carbon atoms with respect to 100 parts by weight of a mixture of carbonaceous powder and phenol resin powder selected from the group consisting of charcoal, activated carbon or a mixture thereof; ; (2) molding the molding mixture obtained in the mixing step into pellets, (2-1) a supplying step of supplying the molding mixture obtained in the mixing step onto the intermediate mold in which molding spheres having a plurality of cylindrical inner spaces are formed; (2-2) the upper mold having a flat bottom surface is moved from the upper side of the middle mold to the middle mold to press the molding mixture on the intermediate mold so that the molding mixture is put into the molding spheres of the intermediate mold and pressurized. Pellet forming step of forming; And (2-3) compression molding in the molding spheres of the intermediate mold by moving the lower mold having the outgoing protrusions having the same shape as the molding spheres of the intermediate mold from below the intermediate mold toward the intermediate mold; A primary molding step of molding into pellets (short cylindrical shaped bodies) by the drawing-out step of pushing out the molding mixture; (3) 80 to 90 while stirring the pellets obtained in the first molding step at a rate of 50 times / minute on a sieve having a scale of 30 to 50 mesh. A secondary molding step of forming a spherical body by applying hot air at a temperature of ℃; (4) carbonizing the spheroid obtained in the secondary molding step by circulating carbon gas at a temperature of 600 to 800 ° C. for 100 to 150 minutes at a circulation rate of 100 to 200 ml / min; And (5) activating the spheroid through the carbonization step by circulating carbon dioxide gas for 100 to 150 minutes at a circulation rate of 100 to 200ml / min at a temperature of 750 to 950 ℃; Spherical activated carbon production method characterized in that it comprises a. The method of claim 1, In the mixing step, the carbonaceous powder is a charcoal powder of 100 to 200 mesh selected from the group consisting of wood charcoal, keratin shell charcoal, chaff charcoal, charcoal charcoal or a mixture of two or more thereof. The method of claim 1, In the mixing step, the carbonaceous powder is a spherical activated carbon production method, characterized in that the metal salt treatment. The method of claim 1, In the mixing step, the mixture of the carbonaceous powder and the phenol resin powder is 58 to 65% by weight of the carbon powder and the phenol resin powder 42 to 35% by weight of the production method of the spherical activated carbon, characterized in that the mixture. delete The method of claim 1, And removing the upper mold from the intermediate mold after the pellet forming step, and then removing the unmixed molding mixture remaining on the intermediate mold. The method of claim 1, The spherical body of the spherical activated carbon further comprises a drying step of drying for 7 to 10 hours in the activated carbon powder at a temperature of 100 to 200 ℃ before performing the carbonization step Manufacturing method. The method of claim 1, And a sorting step of sieving the spherical body having undergone the carbonization step on a sieve having a scale of 50 to 80 mesh before activating in the activation step.

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