METHOD FOR PREPARING POLYANILINE COMPLEX WITH ANTIMICROBIAL ACTIVITY AND HEAVY METAL REMOVAL EFFICIENCY USING CONDUCTIVE POLYANILINE POLYMER DOPED WITH ORGANIC ACID AND METAL ION IN DEFINED ORDER, AND POLYANILINE COMPLEX PREPARED FROM THE SAME

Abstract

Disclosed is a method for preparing an insoluble polyaniline complex with antimicrobial activity and heavy metal removal efficiency that involves doping a porous nonconductive polyaniline emeraldine base with an organic acid to impart conductivity and then with a metal ion to render the metal ion attached to the surface of the conductive polymer, and a polyaniline complex prepared from the preparation method, which polyaniline complex is excellent in the ability to adsorb and/or eliminate bacteria and other microbes and to remove heavy metals and hence available in any of various applications for antimicrobial activity and heavy metal removal, including filters for water purifier, automobile or household air conditioner, gas masks, water and sewage treatment system, air purifier, cleanroom, etc.

Claims

1. A method for preparing a polyaniline complex for antimicrobial activity and heavy metal removal efficiency, the method comprising: (a) synthesizing a polyaniline emeraldine base in the form of a nano-fiber using a conventional interfacial polymerization; (b) doping the polyaniline emeraldine base of the step (a) with an organic acid to prepare a polyaniline emeraldine salt complex; and (c) doping the polyaniline emeraldine salt complex of the step (b) with a metal ion or a metal salt to prepare an insoluble polyaniline/metal complex.

2. The method as claimed in claim 1, wherein the organic acid of the step (b) has a carboxyl group.

3. The method as claimed in claim 2, wherein the organic acid of the step (b) is ethylenediaminetetraacetic acid (EDTA).

4. The method as claimed in claim 1, wherein the organic acid of the step (b) is contained in an amount of 20 to 50 wt. % with respect to the total weight of the conductive polyaniline polymer.

5. The method as claimed in claim 1, wherein the metal ion or the metal salt of the step (c) includes silver (Ag).

6. The method as claimed in claim 5, wherein the metal ion or the metal salt of the step (c) is contained in an amount of 5 to 30 wt. % with respect to the conductive polyaniline polymer.

7. A polyaniline complex for antimicrobial activity and heavy metal removal efficiency as prepared by the method as claimed in claim 1.

8. The polyaniline complex for antimicrobial activity and heavy metal removal efficiency as claimed in claim 7, wherein the polyaniline complex for antimicrobial activity and heavy metal removal efficiency is prepared in a form available for any one selected from the group consisting of a water purifier, a water and sewage treatment system, an automobile, a household appliance, an air purifier, a gas mask, an air conditioner, and a cleanroom.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

[0030] FIG. 1 is an electron micrograph showing that the polyaniline emeraldine base of the present invention has the nano-fiber form with numerous pores.

[0031] FIG. 2 is an electron micrograph showing that the polyaniline emeraldine salt complex prepared by doping the polyaniline emeraldine base with EDTA as an organic acid has a nano-fiber structure with numerous pores.

[0032] FIG. 3 is an electron micrograph showing that silver (Ag) nanoparticles are produced and adsorbed on the surface of the polyaniline/metal complex in the polyaniline emeraldine salt complex doped with an organic acid, EDTA.

[0033] FIG. 4A, FIG. 4B and FIG. 4C are images showing the virus removal activity of the polyaniline complex for antimicrobial activity and heavy metal removal efficiency according to the present invention.

[0034] FIG. 5A, FIG. 5B and FIG. 5C are images showing the bacteria removal activity of the polyaniline complex for antimicrobial activity and heavy metal removal efficiency according to the present invention.

DETAILED DESCRIPTION OF THE INVENTION

[0035] Hereinafter, a detailed description will be given as to the present invention through the following examples, which are not construed to define the scope of the present invention but obviously many modifications and variations are possible in the light of the teaching of the present invention.

Example 1

[0036] Preparation of Polyaniline Complex for Antimicrobial Activity and Heavy Metal Removal Efficiency According to Present Invention

[0037] A description as to the method for preparing a polyaniline complex for antimicrobial activity and heavy metal removal efficiency according to the present invention is given as follows.

[0038] (1) Synthesis of Polyaniline Emeraldine Base in Nano-Fiber Form

[0039] 96 g of aniline was added to 500 ml of chloroform, and 2 L of a 3M aqueous solution of HCl was slowly added over one hour under agitation. The temperature of the reaction bath was maintained at 28 C. with a condenser. 10 g of lithium chloride (LiCl) was added to prevent the solution of the reaction bath from freezing at lower temperature. 57 g of ammonium persulfate used as a radical polymerization initiator was dissolved in 200 ml of water, and the solution was then added dropwise over 2 hours. A 12-hour reaction resulted in producing a polyaniline emeraldine salt doped with hydrochloric acid (HCl). The salt thus obtained was filtered through a filter paper and then treated with ammonia water to prepare 25 g of an HCl-undoped polyaniline emeraldine base in the nano-fiber form. The polyaniline emeraldine base thus obtained was observed with a scanning electron microscope.

[0040] The results are presented in FIG. 1.

[0041] As can be seen from FIG. 1, the polyaniline emeraldine base of the present invention had the nano-fiber form with numerous pores.

[0042] (2) Preparation of Polyaniline Emeraldine Salt Complex

[0043] To dope the synthesized polyaniline emeraldine base with an organic acid, 1 g of ethylenediaminetetraacetic acid (EDTA) was dissolved in 2 L of water, and 2 g of the polyaniline emeraldine base was treated with the aqueous solution of EDTA using an ultrasonic washing machine for one hour. A 12-hour agitation with an agitator ended up producing 2.5 g of an EDTA-doped polyaniline emeraldine salt complex.

[0044] The polyaniline emeraldine salt complex thus obtained was filtered through a filter paper, washed with distilled water multiple times to remove the unreacted EDTA molecules, and then dried out. The dried polyaniline emeraldine salt complex was photographed with a scanning electron microscope.

[0045] The results are presented in FIG. 2.

[0046] As can be seen from FIG. 2, the polyaniline emeraldine salt complex maintained its structure comprised of nano-fibers with numerous pores even though it was doped with an organic acid, EDTA.

[0047] (3) Preparation of Polyaniline/Metal Complex

[0048] To dope the EDTA-doped polyaniline emeraldine salt complex with an antimicrobial metal ion, 5 g of the EDTA-doped polyaniline emeraldine salt complex was soaked with 1 L of a 5% aqueous solution of silver nitrate (AgNO.sub.3) and aged for 2 days to cause a gradual reduction reaction of silver (Ag) ions sticking to the surface of the polymer into silver (Ag) nanoparticles, resulting in producing 5.4 g of an insoluble polyaniline/metal complex with silver nanoparticles on the surface. The polyaniline/metal complex thus obtained was washed with distilled water multiple times to remove the unreacted silver nitrate portion and then dried out. The dried polyaniline/metal complex was photographed with a scanning electron microscope.

[0049] The results are presented in FIG. 3.

[0050] As can be seen from FIG. 3, nano-sized silver (Ag) particles were uniformly created and attached on the surface of the insoluble polyaniline/metal complex.

Comparative Example 1

[0051] Preparation of Polyaniline Complex Doped with Metal Ion and then with Organic Acid

[0052] The procedures were performed to prepare a polyaniline complex for antimicrobial activity and heavy metal removal efficiency in the same manner as described in Example 1, excepting that a polyaniline emeraldine base was doped with silver nitrate (AgNO.sub.3) as an antimicrobial metal ion to prepare a polyaniline/metal complex and then with ethylenediaminetetraacetic acid (EDTA) as an organic acid to prepare a polyaniline emeraldine salt complex, while in Example 1, a polyaniline emeraldine base was doped with EDTA as an organic acid to prepare a polyaniline emeraldine salt complex and then with silver nitrate (AgNO.sub.3) as an antimicrobial metal ion to prepare a polyaniline/metal complex.

[0053] Hereinafter, a detailed description will be given as follows.

[0054] (1) Synthesis of Polyaniline Emeraldine Base

[0055] 96 g of aniline was added to 500 ml of chloroform, and 2 L of a 3M aqueous solution of HCl was slowly added over one hour under agitation. The temperature of the reaction bath was maintained at 28 C. with a condenser. 10 g of lithium chloride (LiCl) was added to prevent the solution of the reaction bath from freezing at lower temperature. 57 g of ammonium persulfate used as a radical polymerization initiator was dissolved in 200 ml of water, and the solution was added dropwise over 2 hours. A 12-hour reaction resulted in producing a polyaniline emeraldine salt doped with hydrochloric acid (HCl). The salt thus obtained was filtered through a filter paper and then treated with ammonia water to prepare 25 g of an HCl-undoped polyaniline emeraldine base in the nano-fiber form.

[0056] (2) Preparation of Polyaniline/Metal Complex

[0057] To dope the synthesized polyaniline emeraldine base with an antimicrobial metal ion, 5 g of the polyaniline emeraldine base was soaked with 1 L of a 5% aqueous solution of silver nitrate (AgNO.sub.3) and aged for 2 days to cause a gradual reduction reaction of silver (Ag) ions sticking to the surface of the polymer into silver (Ag) nanoparticles, resulting in producing 5.4 g of an insoluble polyaniline/metal complex with silver nanoparticles on the surface. The polyaniline/metal complex thus obtained was washed with distilled water multiple times to remove the unreacted silver nitrate portion and then dried out.

[0058] (3) Preparation of Polyaniline Emeraldine Salt Complex

[0059] To dope the metal-ion-doped polyaniline/metal complex with an organic acid, 1 g of ethylenediaminetetraacetic acid (EDTA) was dissolved in 2 L of water, and 2 g of the polyaniline/metal complex was treated with the aqueous solution of EDTA using an ultrasonic washing machine for one hour. A 12-hour agitation with an agitator ended up producing 2.5 g of an EDTA-doped polyaniline emeraldine salt complex.

[0060] The polyaniline emeraldine salt complex thus obtained was filtered through a filter paper, washed with distilled water multiple times to remove the unreacted EDTA molecules, and then dried out.

Comparative Example 2

[0061] Preparation of Polyaniline Complex Using Organic Acid as Sole Dopant

[0062] (1) Synthesis of Polyaniline Emeraldine Base

[0063] 96 g of aniline was added to 500 ml of chloroform, and 2 L of a 3M aqueous solution of HCl was slowly added over one hour under agitation. The temperature of the reaction bath was maintained at 28 C. with a condenser. 10 g of lithium chloride (LiCl) was added to prevent the solution of the reaction bath from freezing at lower temperature. 57 g of ammonium persulfate used as a radical polymerization initiator was dissolved in 200 ml of water, and the solution was then added dropwise over 2 hours. A 12-hour reaction resulted in producing a polyaniline emeraldine salt doped with hydrochloric acid (HCl). The salt thus obtained was filtered through a filter paper and then treated with ammonia water to prepare 25 g of an HCl-undoped polyaniline emeraldine base in the nano-fiber form.

[0064] (2) Preparation of Polyaniline Emeraldine Salt Complex

[0065] To dope the synthesized polyaniline emeraldine base with an organic acid, 1 g of ethylenediaminetetraacetic acid (EDTA) was dissolved in 2 L of water, and 2 g of the polyaniline emeraldine base was treated with the aqueous solution of EDTA using an ultrasonic washing machine for one hour. A 12-hour agitation with an agitator ended up producing 2.5 g of an EDTA-doped polyaniline emeraldine salt complex.

[0066] The polyaniline emeraldine salt complex thus obtained was filtered through a filter paper, washed with distilled water multiple times to remove the unreacted EDTA molecules, and then dried out.

Comparative Example 3

[0067] Preparation of Polyaniline Complex Doped Using Metal Ion as Sole Dopant

[0068] (1) Synthesis of Polyaniline Emeraldine Base

[0069] 96 g of aniline was added to 500 ml of chloroform, and 2 L of a 3M aqueous solution of HCl was slowly added over one hour under agitation. The temperature of the reaction bath was maintained at 28 C. with a condenser. 10 g of lithium chloride (LiCl) was added to prevent the solution of the reaction bath from freezing at lower temperature. 57 g of ammonium persulfate used as a radical polymerization initiator was dissolved in 200 ml of water, and the solution was then added dropwise over 2 hours. A 12-hour reaction resulted in producing a polyaniline emeraldine salt doped with hydrochloric acid (HCl). The salt thus obtained was filtered through a filter paper and then treated with ammonia water to prepare 25 g of an HCl-undoped polyaniline emeraldine base in the nano-fiber form.

[0070] (2) Preparation of Polyaniline/Metal Complex

[0071] To dope the synthesized polyaniline emeraldine base with an antimicrobial metal ion, 5 g of the polyaniline emeraldine base was soaked with 1 L of a 5% aqueous solution of silver nitrate (AgNO.sub.3) and aged for 2 days to cause a gradual reduction reaction of silver (Ag) ions sticking to the surface of the polymer into silver (Ag) nanoparticles, resulting in producing 5.4 g of an insoluble polyaniline/metal complex with silver nanoparticles on the surface. The polyaniline/metal complex thus obtained was washed with distilled water multiple times to remove the unreacted silver nitrate portion and then dried out.

Experimental Example 1

[0072] Antimicrobial Activity Testing when Using Organic Acid and Metal Ion as Dopants in Different Doping Orders

[0073] 2 g of the polyaniline complex for antimicrobial activity and heavy metal removal efficiency according to the present invention in Example 1 was filled in a 1612 urethane hose to prepare a specimen filter for water purifier.

[0074] To prepare a control filter, the procedures were performed in the same manner as described above, excepting that the polyaniline complex of Comparative Example 1 was used.

[0075] 1-1. Virus Removal Testing

[0076] The virus as used herein was MS2 virus, and the virus removal efficiency was evaluated according to the VF international standards.

[0077] More specifically, MS2 virus was added to water in an amount of 1 ml per 5 L of water to prepare an aqueous solution, which was then passed through a filter for water purifier under the pressure of 1 kg at a rate of 60 ml/min. 500 ml of the aqueous solution obtained as a filtrate was subjected to a virus removal testing.

[0078] The testing results are presented in Table 1 and FIG. 4.

[0079] In FIG. 4A, the image (A) shows a log reduction of MS2 virus counts from a 6 input log to a less than 4 output log in the virus removal testing; in FIG. 4B, the image (B) shows a 5 log reduction of the input virus; and in FIG. 4C, the image (C) shows a 6 log reduction.

[0080] As can be seen from Table 1 and FIG. 4, the polyaniline complex for antimicrobial activity and heavy metal removal efficiency according to the present invention in Example 1 had a 6.1 input log of the virus on the first day and a 5.7 log reduction of the input virus on the fourth day, showing that more than 90% of the input virus was consistently removed.

[0081] On the other hand, the polyaniline complex of Comparative Example 1 as prepared using a metal ion and then an organic acid as dopants in a different doping order from Example 1 had a 6.3 input log of the virus on the first day and a 2.3 log reduction of the input virus on the fourth day, showing that no more than about 30% of the input virus was removed.

[0082] In conclusion, the polyaniline complex prepared by doping with an organic acid and then with a metal ion according to the present invention was superior in the virus removal efficiency to the polyaniline complex prepared by doping with a metal ion and then with an organic acid according to Comparative Example 1.

TABLE-US-00001 TABLE 1 Virus Input Output Log Div. pfu/ml Input log log reduction Example 1 1.sup.st day 1.9 10.sup.6 6.1 0.0 6.1 4.sup.th day 1.9 10.sup.6 6.1 0.4 5.7 Comparative 1.sup.st day 1.9 10.sup.6 6.3 0.0 6.3 Example 1 4.sup.th day 1.9 10.sup.6 6.3 4.0 2.3

[0083] 1-2. Bacteria Removal Testing

[0084] The bacterium as used herein was E. coli, and the bacteria removal efficiency was evaluated according to the VF international standards.

[0085] More specifically, E. coli was added to water in an amount of 1 ml per 3 L of water to prepare an aqueous solution, which was then passed through a filter for water purifier under the pressure of 1 kg at a rate of 60 ml/min. 500 ml of the aqueous solution obtained as a filtrate was subjected to a bacteria removal testing.

[0086] The testing results are presented in Table 2 and FIG. 5.

[0087] In FIG. 5A, the image (A) shows a log reduction of E. coli counts from an 8 input log to a less than 6 output log in the bacteria removal testing; in FIG. 5B, the image (B) shows a 6-8 log reduction of E. coli; in FIG. 5C, and the image (C) shows an 8 log reduction of E. coli.

[0088] As can be seen from Table 2 and FIG. 5, the polyaniline complex for antimicrobial activity and heavy metal removal efficiency according to the present invention in Example 1 had an 8.0 input log of E. coli on the first day and an about 7.2 log reduction of E. coli on the fourth day, showing that more than 90% of the bacteria was consistently removed.

[0089] On the other hand, the polyaniline complex of Comparative Example 1 as prepared in a different doping order with a metal ion and an organic acid had an 8.3 input log of E. coli on the first day and a 4.0 log reduction of E. coli on the fourth day, showing that no more than about 50% of the bacteria was removed.

[0090] In conclusion, the polyaniline complex prepared by doping with an organic acid and then with a metal ion according to the present invention was superior in the bacteria removal efficiency to the polyaniline complex prepared by doping with a metal ion and then with an organic acid according to Comparative Example 1.

TABLE-US-00002 TABLE 2 Bacteria Input Output Log Div. pfu/ml Input log log reduction Example 1 1.sup.st day 1.9 10.sup.6 8.0 0.0 8.0 4.sup.th day 1.9 10.sup.6 8.0 0.8 7.2 Comparative 1.sup.st day 1.9 10.sup.6 8.3 0.0 8.3 Example 1 4.sup.th day 1.9 10.sup.6 8.3 4.3 4.0

Experimental Example 2

[0091] Antimicrobial Activity Testing when Using Organic Acid as Sole Dopant

[0092] 2 g of the polyaniline complex for antimicrobial activity and heavy metal removal efficiency according to the present invention in Example 1 was filled in a 1612 urethane hose to prepare a specimen filter for water purifier.

[0093] To prepare a control filter, the procedures were performed in the same manner as described above, excepting that the polyaniline complex of Comparative Example 2 was used.

[0094] 2-1. Virus Removal Testing

[0095] The virus as used herein was MS2 virus, and the virus removal efficiency was evaluated according to the VF international standards.

[0096] More specifically, MS2 virus was added to water in an amount of 1 ml per 5 L of water to prepare an aqueous solution, which was then passed through a filter for water purifier under the pressure of 1 kg at a rate of 60 ml/min. 500 ml of the aqueous solution obtained as a filtrate was subjected to a virus removal testing.

[0097] The testing results are presented in Table 3.

[0098] As can be seen from Table 3, the polyaniline complex for antimicrobial activity and heavy metal removal efficiency according to the present invention in Example 1 had a 6.1 input log of the virus on the first day and a 5.7 log reduction of the input virus on the fourth day, showing that more than 90% of the input virus was consistently removed.

[0099] On the other hand, the polyaniline complex of Comparative Example 2 as prepared using an organic acid as a sole dopant had a 6.0 input log of the virus on the first day and a 3.1 log reduction of the input virus on the fourth day, showing that no more than about 50% of the input virus was removed.

[0100] In conclusion, the polyaniline complex prepared by doping with an organic acid and then with a metal ion according to the present invention was far superior in the virus removal efficiency to the polyaniline complex prepared by doping with an organic acid solely according to Comparative Example 2.

TABLE-US-00003 TABLE 3 Virus Input Output Log Div. pfu/ml Input log log reduction Example 1 1.sup.st day 1.9 10.sup.6 6.1 0.0 6.1 4.sup.th day 1.9 10.sup.6 6.1 0.4 5.7 Comparative 1.sup.st day 1.9 10.sup.6 6.0 0.0 6.1 Example 2 4.sup.th day 1.9 10.sup.6 6.0 2.9 3.1

[0101] 2-2. Bacteria Removal Testing

[0102] The bacterium as used herein was E. coli, and the bacteria removal efficiency was evaluated according to the VF international standards.

[0103] More specifically, E. coli was added to water in an amount of 1 ml per 3 L of water to prepare an aqueous solution, which was then passed through a filter for water purifier under the pressure of 1 kg at a rate of 60 ml/min. 500 ml of the aqueous solution obtained as a filtrate was subjected to a bacteria removal testing.

[0104] The testing results are presented in Table 4.

[0105] As can be seen from Table 4, the polyaniline complex for antimicrobial activity and heavy metal removal efficiency according to the present invention in Example 1 had an 8.0 input log of E. coli on the first day and an about 7.2 log reduction of E. coli on the fourth day, showing that more than 90% of the bacteria was consistently removed.

[0106] On the other hand, the polyaniline complex of Comparative Example 2 as prepared using an organic acid as a sole dopant had an 8.0 input log of E. coli on the first day and a 5.1 log reduction of E. coli on the fourth day, showing that about 60% of the bacteria was removed.

[0107] In conclusion, the polyaniline complex prepared by doping with an organic acid and then with a metal ion according to the present invention was far superior in the bacteria removal efficiency to the polyaniline complex prepared by doping with an organic acid solely according to Comparative Example 2.

TABLE-US-00004 TABLE 4 Bacteria Input Output Log Div. pfu/ml Input log log reduction Example 1 1.sup.st day 1.9 10.sup.6 8.0 0.0 8.0 4.sup.th day 1.9 10.sup.6 8.0 0.8 7.2 Comparative 1.sup.st day 1.9 10.sup.6 8.0 0.0 8.3 Example 2 4.sup.th day 1.9 10.sup.6 8.0 2.9 5.1

Experimental Example 3

[0108] Antimicrobial Activity Testing when Using Metal Ion as Sole Dopant

[0109] 2 g of the polyaniline complex for antimicrobial activity and heavy metal removal efficiency according to the present invention in Example 1 was filled in a 1612 urethane hose to prepare a specimen filter for water purifier.

[0110] To prepare a control filter, the procedures were performed in the same manner as described above, excepting that the polyaniline complex of Comparative Example 3 was used.

[0111] 3-1. Virus Removal Testing

[0112] The virus as used herein was MS2 virus, and the virus removal efficiency was evaluated according to the VF international standards.

[0113] More specifically, MS2 virus was added to water in an amount of 1 ml per 5 L of water to prepare an aqueous solution, which was then passed through a filter for water purifier under the pressure of 1 kg at a rate of 60 ml/min. 500 ml of the aqueous solution obtained as a filtrate was subjected to a virus removal testing.

[0114] The testing results are presented in Table 5.

[0115] As can be seen from Table 5, the polyaniline complex for antimicrobial activity and heavy metal removal efficiency according to the present invention in Example 1 had a 6.1 input log of the virus on the first day and a 5.7 log reduction of the input virus on the fourth day, showing that more than 90% of the input virus was consistently removed.

[0116] On the other hand, the polyaniline complex of Comparative Example 3 as prepared using a metal ion as a sole dopant had a 6.0 input log of the virus on the first day and a 3.8 log reduction of the input virus on the fourth day, showing that no more than about 50% of the input virus was removed.

[0117] In conclusion, the polyaniline complex prepared by doping with an organic acid and then with a metal ion according to the present invention was far superior in the virus removal efficiency to the polyaniline complex prepared by doping with a metal ion solely according to Comparative Example 3.

TABLE-US-00005 TABLE 5 Virus Input Output Log Div. pfu/ml Input log log reduction Example 1 1.sup.st day 1.9 10.sup.6 6.1 0.0 6.1 4.sup.th day 1.9 10.sup.6 6.1 0.4 5.7 Comparative 1.sup.st day 1.9 10.sup.6 6.0 0.0 6.0 Example 3 4.sup.th day 1.9 10.sup.6 6.0 2.2 3.8

[0118] 3-2. Bacteria Removal Testing

[0119] The bacterium as used herein was E. coli, and the bacteria removal efficiency was evaluated according to the VF international standards.

[0120] More specifically, E. coli was added to water in an amount of 1 ml per 3 L of water to prepare an aqueous solution, which was then passed through a filter for water purifier under the pressure of 1 kg at a rate of 60 ml/min. 500 ml of the aqueous solution obtained as a filtrate was subjected to a bacteria removal testing.

[0121] The testing results are presented in Table 6.

[0122] As can be seen from Table 6, the polyaniline complex for antimicrobial activity and heavy metal removal efficiency according to the present invention in Example 1 had an 8.0 input log of E. coli on the first day and an about 7.2 log reduction of E. coli on the fourth day, showing that more than 90% of the bacteria was consistently removed.

[0123] On the other hand, the polyaniline complex of Comparative Example 3 as prepared using a metal ion as a sole dopant had a 6.0 input log of E. coli on the first day and a 3.8 log reduction of E. coli on the fourth day, showing that about 60% of the bacteria was removed.

[0124] In conclusion, the polyaniline complex prepared by doping with an organic acid and then with a metal ion according to the present invention was far superior in the bacteria removal efficiency to the polyaniline complex prepared by doping with a metal ion solely according to Comparative Example 3.

TABLE-US-00006 TABLE 6 Bacteria Input Output Log Div. pfu/ml Input log log reduction Example 1 1.sup.st day 1.9 10.sup.6 8.0 0.0 8.0 4.sup.th day 1.9 10.sup.6 8.0 0.8 7.2 Comparative 1.sup.st day 1.9 10.sup.6 6.0 0.0 6.0 Example 3 4.sup.th day 1.9 10.sup.6 6.0 2.2 3.8

Experimental Example 4

[0125] Testing for Heavy Metal Removal when Using Organic Acid and Metal Ion as Dopants in Different Doping Orders

[0126] 2 g of the polyaniline complex for antimicrobial activity and heavy metal removal efficiency according to the present invention in Example 1 was filled in a 1612 urethane hose to prepare a specimen filter for heavy metal removal. Then, 2 L of an aqueous solution containing 1,000 ppm of heavy metal ions was passed through the filter to calculate the final TDS value with respect to the initial measurement value and determine the heavy metal removal efficiency.

[0127] The procedures were performed in the same manner as described above to prepare a control filter and carry out a testing, excepting that the polyaniline complex of Comparative Example 1 was used.

[0128] The testing results are presented in Table 7.

[0129] As can be seen from Table 7, the heavy metal removal testing showed that the polyaniline complex for antimicrobial activity and heavy metal removal efficiency according to the present invention had considerably high heavy metal removal efficiencies; 99% for nickel, 90% for lead, 91% for cadmium, 91% for zinc, 88% for copper, 88% for mercury, and 86% for chrome.

[0130] On the other hand, the polyaniline complex of Comparative Example 1 as prepared using a metal ion and then an organic acid as dopants in a different doping order from Example 1 had relatively low heavy metal removal efficiencies; 85% for nickel, 95% for lead, 90% for cadmium, 77% for zinc, 89% for copper, 93% for mercury, and 95% for chrome.

[0131] In conclusion, the polyaniline complex prepared by doping with an organic acid and then with a metal ion according to the present invention was superior in the heavy metal removal efficiency to the polyaniline complex prepared by doping with a metal ion and then with an organic acid according to Comparative Example 1.

TABLE-US-00007 TABLE 7 Heavy metal removal efficiency (%) Heavy metal Example 1 Comparative Example 1 Nickel 99 85 Lead 90 95 Cadmium 91 90 Zinc 91 77 Copper 88 89 Mercury 88 93 Chrome 86 95

Experimental Example 5

[0132] Testing for Heavy Metal Removal when Using Organic Acid as Sole Dopant

[0133] 2 g of the polyaniline complex for antimicrobial activity and heavy metal removal efficiency according to the present invention in Example 1 was filled in a 1612 urethane hose to prepare a specimen filter for heavy metal removal. Then, 2 L of an aqueous solution containing 1,000 ppm of heavy metal ions was passed through the filter to calculate the final TDS value with respect to the initial measurement value and determine the heavy metal removal efficiency.

[0134] The procedures were performed in the same manner as described above to prepare a control filter and carry out a testing, excepting that the polyaniline complex of Comparative Example 2 was used.

[0135] The testing results are presented in Table 8.

[0136] As can be seen from Table 8, the heavy metal removal testing showed that the polyaniline complex for antimicrobial activity and heavy metal removal efficiency according to the present invention had considerably high heavy metal removal efficiencies; 99% for nickel, 90% for lead, 91% for cadmium, 91% for zinc, 88% for copper, 88% for mercury, and 86% for chrome.

[0137] On the other hand, the polyaniline complex of Comparative Example 2 as prepared using an organic acid as a sole dopant had relatively low heavy metal removal efficiencies; 81% for nickel, 78% for lead, 81% for cadmium, 75% for zinc, 59% for copper, 67% for mercury, and 82% for chrome.

[0138] In conclusion, the polyaniline complex prepared by doping with an organic acid and then with a metal ion according to the present invention was superior in the heavy metal removal efficiency to the polyaniline complex prepared by doping with an organic acid solely according to Comparative Example 2.

TABLE-US-00008 TABLE 8 Heavy metal removal efficiency (%) Heavy metal Example 1 Comparative Example 2 Nickel 99 81 Lead 90 78 Cadmium 91 81 Zinc 91 75 Copper 88 59 Mercury 88 67 Chrome 86 82

Experimental Example 6

[0139] Testing for Heavy Metal Removal when Using Metal Ion as Sole Dopant

[0140] 2 g of the polyaniline complex for antimicrobial activity and heavy metal removal efficiency according to the present invention in Example 1 was filled in a 1612 urethane hose to prepare a specimen filter for heavy metal removal. Then, 2 L of an aqueous solution containing 1,000 ppm of heavy metal ions was passed through the filter to calculate the final TDS value with respect to the initial measurement value and determine the heavy metal removal efficiency.

[0141] The procedures were performed in the same manner as described above to prepare a control filter and carry out a testing, excepting that the polyaniline complex of Comparative Example 3 was used.

[0142] The testing results are presented in Table 9.

[0143] As can be seen from Table 9, the heavy metal removal testing showed that the polyaniline complex for antimicrobial activity and heavy metal removal efficiency according to the present invention had considerably high heavy metal removal efficiencies; 99% for nickel, 90% for lead, 91% for cadmium, 91% for zinc, 88% for copper, 88% for mercury, and 86% for chrome.

[0144] On the other hand, the polyaniline complex of Comparative Example 3 as prepared using a metal ion as a sole dopant had relatively low heavy metal removal efficiencies; 72% for nickel, 82% for lead, 78% for cadmium, 67% for zinc, 73% for copper, 72% for mercury, and 70% for chrome.

[0145] In conclusion, the polyaniline complex prepared by doping with an organic acid and then with a metal ion according to the present invention was superior in the heavy metal removal efficiency to the polyaniline complex prepared by doping with a metal ion solely according to Comparative Example 3.

TABLE-US-00009 TABLE 9 Heavy metal removal efficiency (%) Heavy metal Example 1 Comparative Example 3 Nickel 99 72 Lead 90 82 Cadmium 91 78 Zinc 91 67 Copper 88 73 Mercury 88 72 Chrome 86 70