KR101169523B1 - Method for preparing metal nanoparticles using biomass - Google Patents

Abstract

The present invention relates to a method for producing metal nanoparticles that produce metal nanoparticles by reducing metal ions adsorbed on a surface of biomass to biomass. In the present invention, since metal ions are reduced by adsorption of metal ions through biomass and reducing substances present on the surface or inside of biomass, metal nanoparticles are not eco-friendly, economical and harmless to humans without using chemicals such as reducing agents. Particles can be prepared.

Description

 Method for preparing metal nanoparticles using biomass {Method for preparing metal nanoparticles using biomass}

The present invention relates to a method for producing metal nanoparticles using biomass, and more particularly to a method for producing metal nanoparticles by reducing metal ions adsorbed on the surface of biomass to biomass to produce metal nanoparticles. .

Metal nanoparticles have been manufactured by physical or chemical methods, but physical methods require expensive equipment, and chemical methods require post-treatment processes due to the toxicity of electron donors and organic solvents.

On the other hand, countries not only increase the value of metals as oil resources but also raise the concern about the ecological effects of toxic metals released into the natural environment, which removes and recovers metals from wastewater, groundwater, soil or waste. Research is being actively conducted. Conventional methods of treating heavy metal wastewater include oxidation / reduction method, flocculation sedimentation method, adsorption, ion exchange method, electrolysis method, neutralization method, extraction method, etc. The flocculation sedimentation method and ion exchange resin method are most commonly used, but these processes are particularly used in solution. When metals in the range of 1 to 100 mg / L are contained, they are inefficient or very expensive (Water Treatment Principles and Design, John Wiley and Sons, 1985).

Adsorption technology using activated carbon looks promising in recovering valuable metals, but it is expensive to prepare the necessary carbon. Meanwhile, in the adsorption method using microorganisms, microorganisms have a metal-binding portion, which is environmentally friendly, and various studies are being conducted. For example, biosorption of silver ions using Thiobacillus sp. And Cladosporium sp. Has been suggested (Pethkar et al., 2001). It is also known that many kinds of bacteria reduce the ionic form of valuable metals to zero-valent nanoparticles. However, the exact mechanism by which these microorganisms reduce metal ions to produce nanoparticles is not known.

One technical problem to be solved by the present invention is to provide a method for generating metal nanoparticles by adsorbing and reducing the metal ions in the waste water using biomass.

One aspect of the invention, the step of adsorbing metal ions by stirring a mixture of a water-soluble metal compound and bacterial biomass, reducing the metal ions adsorbed on the surface of the bacterial biomass to the bacterial biomass to produce metal nanoparticles It relates to a method for producing metal nanoparticles comprising the step of.

Another aspect of the invention relates to metal nanoparticles produced by the method.

In the present invention, since metal ions are reduced by adsorption of metal ions through biomass and reducing substances present on the surface or inside of biomass, metal nanoparticles are not eco-friendly, economical and harmless to humans without using chemicals such as reducing agents. Particles can be prepared.

1 is a schematic diagram showing the structure of a main functional group when bacterial biomass is present in an aqueous solution.
2 is a TEM image of the activated bacterial biomass (a) and the inactivated biomass (b) surface after the metal nanoparticle generation step.
Figure 3 shows the amount of silver ions adsorption according to the adsorption time in Example 1.
4 is a UV-vis spectrum for identifying silver nanoparticles produced by Example 1. FIG.
Figure 5 is an analysis of the X-ray diffraction (XRD) pattern of the silver nanoparticles produced by Example 1.
6 is a graph showing the analysis of the maximum adsorption amount for each metal ion concentration of RB (a) and PEIB (b).
Figure 7 shows the metal nanoparticles produced in Experimental Example 1 by TEM after 24 hours.
8 is a graph showing the analysis of metal ion adsorption amount of PEIB and RB over time.
9 is a TEM image of an image of reduced metal nanoparticles analyzed over time.

The method for preparing metal nanoparticles according to the present invention includes the steps of adsorbing metal ions onto bacterial biomass and reducing metal ions adsorbed on the bacterial biomass to the bacterial biomass to produce metal nanoparticles.

Hereinafter, the present invention will be described in more detail.

First, the surface-modified biomass that can be used in the nanoparticle manufacturing method of the present invention will be described in detail.

In the present invention, "biomass" refers to a living or dead biological material (biomass) that can be used for industrial production, in particular the bacterial biomass of the present invention bacteria such as E. coli or Corynebacterium It means biomass consisting of cells.

Bacteria such as Escherichia coli and Corynebacterium are widely used as strains producing substances such as antibiotics, anticancer agents, amino acids and nucleic acids. They are killed after being used and discarded as solid fermentation waste.

Figure 1 is a schematic diagram showing the structure of the main functional group when the solid waste bacterial biomass is present in the aqueous solution. Referring to FIG. 1, the bacterial biomass is rich in anionic functional groups (carboxyl or phosphate groups) and cationic functional groups (amine groups).

In the present invention, a cationic compound or polymer containing a large amount of cationic functional groups, such as amine groups and amino groups, is introduced to the surface of the bacterial biomass to increase the content of the cationic functional groups in order to adsorb metal ions exhibiting anionicity in solution. Or anionic functional groups are blocked or removed.

In the present invention, a compound or polymer containing a large amount of anionic functional groups such as carboxyl group, phosphoric acid group, sulfonic acid group and hydroxyl group in order to adsorb metal ions exhibiting cationicity in solution is further introduced on the surface of the bacterial biomass to obtain anionic functional group. Increasing the content, or those in which the cationic functional groups are blocked or removed can be used.

The bacterial biomass preferably comprises an amine group-containing cationic polymer crosslinked on its surface.

As used herein, the term “amine group-containing cationic polymer” refers to a polymer having an amine group in the main chain or side chain and having a totally positive charge. The amine group-containing cationic polymer of the present invention is one or more cations. It can be prepared by polymerizing a monomer, or by polymerizing one or more nonionic monomers and one or more cationic monomers.

The method for crosslinking the amine group-containing cationic polymer to the bacterial biomass is not particularly limited, but preferably the amine group-containing cationic polymer is crosslinked to the bacterial biomass surface by an amine group or a hydroxy group. It is preferable.

In the present invention, bacterial biomass is Corynebacterium sp .), Escherichia sp . , Bacillus sp . ) And Serratia sp . It may be composed of one or more bacterial cells selected from the group consisting of).

Non-limiting examples of the bacteria that make up these bacterial biomass are Corynebac

Coriumbacterium ammoniagenes, Corynebacterium glutamicum, Escherichia coli, Bacillus megatherium and Serratia marcescens and Brea Bacteria, such as non-bacterium ammonia genes.

In addition to the above-mentioned bacteria, Corynebacterium betae, Corynebacterium beticola, Corynebacterium bovis, Corynebacterium callunae, Corynebacterium Corybacterium fascians, Corynebacterium flak, Corynebacterium diphtheriae, Corynebacterium equi, Corynebacterium fascians flaccumfaci, Corynebacterium flavescens, Corynebacterium hoagii, Corynebacterium ilicis, Corynebacterium insidiosum, Corynebacterio insidium bacterio Bacteria, such as Neybacterium kutscheri and Corynebacterium lilium, It may include.

Examples of the amine group-containing cationic polymer usable in the present invention include polyethyleneimine, amine-terminated polyethylene oxide, amine-terminated polyethylene / propylene oxide, polymer of dimethyl amino ethyl methacrylate and dimethyl aminoethyl meta It can be selected from the group consisting of copolymers of acrylate and vinylpyrrolidone, linear polymers of epichlorohydrin and dimethylamine, polydiallyldimethylammonium chloride, polyethanolamine / methylchloride and modified polyethyleneimines. .

The amine group-containing cationic polymer may be a polyethyleneimine homopolymer of Formula 1 or a modified polyethyleneimine.

[Formula 1]

Wherein n is from 10 to 500.

The amine group-containing cationic polymer may have a cationic charge of 70 mol% or more, and the molecular weight of the amine group-containing cationic polymer is not particularly limited, but may be, for example, in the range of 1000 to 200,000.

The amine group-containing cationic polymer is a polyethyleneimine homolimer and the biomass may be a biomass of Corynebacterium glutamicum.

When producing a surface modified bacterial biomass by the method of the present invention, first, the dried bacterial biomass is added to the amine group-containing cationic polymer solution and reacted. Subsequently, a crosslinking agent is added to the bacterial biomass and the amine group-containing cationic polymer solution to react, and finally, the biomass is washed and dried to prepare a surface modified bacterial biomass.

The amine group-containing cationic polymer solution may include one or more selected from the group consisting of water, alcohol, chloroform and pyridine as a solvent. In this step, it is preferable to disperse the biomass in a sufficient amount of the amine group-containing cationic polymer. For example, the ratio of the biomass and the amine group-containing cationic polymer is 1: 0.5-2 (w: w). ), Preferably it is mixed in 1: 1 or (w: w).

The temperature for reacting the bacterial biomass with the amine group-containing cationic polymer is not particularly limited, but may be, for example, reacted at a temperature of about 20 ° C. to 150 ° C. to increase the reaction efficiency.

When the amine group-containing cationic polymer is crosslinked on the surface of the bacterial biomass, the crosslinking agent is treated to secure the chemical bond between the bacterial biomass and the amine group-containing cationic polymer. In this case, at least one selected from the group consisting of glutaraldehyde, isocyanide derivatives, and bisdiazobibenzidine may be used as the crosslinking agent.

As shown in FIG. 2, when treating the crosslinking agent, the crosslinking agent may be mixed in a volume ratio of about 1: 1 to 10: 1 with respect to the mixed solution of the biomass and the amine group-containing cationic polymer in a solution state. Preferably it is mixed at a volume ratio of about 5: 1.

The surface-modified bacterial biomass usable in the present invention may be one in which an anionic functional group on the surface is blocked or removed to increase the adsorption capacity of the anionic complex.

As shown in FIG. 1, since anionic functional groups such as carboxyl groups and phosphate groups present on the surface of the bacterial biomass exist in the state of being negatively charged in water, the repulsive force acts on the anionic valuable metal complex or metal ion. do. This repulsive force interferes with the binding of biomass with anionic complexes or metal ions.

The bacterial biomass may use a surface-modified biomass substituted with a compound having a cationic functional group, such as an amine group, a phosphate group, a sulfonic acid group, and an anionic functional group serving as a hinder.

The bacterial biomass may use a surface-modified biomass in which a carboxyl group, phosphoric acid group, or sulfonic acid group on its surface is alkylated, cycloalkylated, or arylated.

An example of the surface-modified biomass may be represented by the following Chemical Formula 1, wherein Chemical Formula 1 is a structure in which hydrogen of the carboxyl or phosphate group of the bacterial biomass is substituted with an alkyl group, a cycloalkyl group, an aryl group, or an amine group. .

[Formula 2]

Biomass - COO R

In the above formula, R is an alkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, or an aryl group having 6 to 15 carbon atoms or NR ₁ R ₂ . Wherein R 1 and R 2 are each hydrogen, an alkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, or an aryl group having 6 to 15 carbon atoms.

In the above formula, if the carbon number is too high, there may be some difficulties in commercialization, and therefore, it is more preferable to alkylate with an alkyl group having 1 to 6 carbon atoms, and most preferably methylation.

The method of alkylating, cycloalkylating and arylating the amino group of the biomass may include reacting the biomass in a mixed solution of aldehyde and carboxylic acid.

Although the content ratio of the aldehyde, carboxylic acid, and biomass is not necessarily limited, it is preferable to react the mixed solution of 1 ml to 40 ml of aldehyde and 1 ml to 160 ml of carboxylic acid based on 1 g of biomass.

In the above content, the volume ratio of aldehyde and carboxylic acid is more preferably 1 to 1/4.

It is most preferable that the content ratio of the aldehyde, the carboxylic acid and the biomass is 20ml: 40ml: 1g.

It is preferable that the aldehyde is formaldehyde and the carboxylic acid is formic acid in terms of reducibility, and a method of alkylating the amino group of the biomass using the same may be represented by the following Scheme 1.

[Reaction Scheme 1]

The reaction is preferably reacted for 1 to 48 hours at 10 to 100 ℃. The reaction may be reacted at 10 to 1000 rpm in a mixed reactor.

On the other hand, when the valuable metal complex or the metal ion is cationic, it is possible to use a surface modified biomass with increased anionicity. By further combining a compound having at least one of a carboxyl group, a sulfonic acid group and a phosphoric acid group to the raw material biomass, a bacterial biomass with increased anionicity can be prepared.

Compound having a carboxyl group further bonded to the raw material biomass may be represented by the formula (1).

(3)

R ₁ -CH ₂ -OOCH ₂ -Biomass

In the above formula, R ₁ is a carboxyl group, a linear or branched alkyl group having 1 to 10 carbon atoms, at least one carboxyl group, an alkenyl group or an alkoxy group, or represented by the following general formula (4).

[Formula 4]

Wherein R ₂ and R ₃ are each H, —OH, —COOH, —CH ₂ —OOH.

The compound having the carboxyl group may be represented by the following formula (4). Formula 4 is a structure in which the amine group or amino group of the raw material biomass is substituted with a compound having a carboxyl group.

[Chemical Formula 5]

-NH ₂ R ₄ COOR ₅

Wherein R ₄ is a linear or branched alkylene group having 1-10 carbon atoms, a linear or branched alkenylene group having 2-10 carbon atoms and R ₅ is H, Na or K.

 In addition, the bacterial biomass may use a surface-modified biomass in which the amine group or amino group, which is a cationic functional group, is substituted with a compound having an anionic functional group such as a carboxyl group, a phosphoric acid group, or a sulfonic acid group.

It is preferable that the said compound is a C1-C10 alkyl group, a C3-C10 cycloalkyl group, or a C6-C15 aryl group. It is more preferable to alkylate with an alkyl group having 1 to 6 carbon atoms, and most preferably methylate the amino group present in the biomass.

The structure in which the amine group or amino group of the biomass is alkylated, cycloalkylated, or arylated may be represented by the following Chemical Formula 1. Substituted amino groups with alkyl groups, cycloalkyl groups, and aryl groups will be referred to as alkylation, cycloalkylation, and arylation.

[Formula 6]

Biomass - N (R) ₂

Wherein R is an alkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, or an aryl group having 6 to 15 carbon atoms.

Hereinafter, a method of preparing metal nanoparticles using the bacterial biomass will be described in detail.

Metal ion adsorption step

The step is a step of adsorbing metal ions by stirring a mixture of a water-soluble metal compound and bacterial biomass.

 The biomass may use the above-described biomass, the surface-modified biomass, and may use an active (live) or inactive (dead) biomass.

The bacterial biomass may be washed with distilled water after culturing to separate the culture medium and to remove the media component from the surface of the biomass.

The inactivated bacterial biomass may be used by sterilization treatment, preferably, heat sterilization treatment. The sterilizer may be heat sterilized at about 10 minutes to 2 hours at a high temperature of 100 degrees or more.

The deactivated biomass may release the reducing material therein to the bacterial biomass surface during thermal sterilization. The inactivated bacterial biomass may reduce metal ions by the reducing material on its surface.

As the water-soluble metal compound, a water-soluble metal salt, a water-soluble metal oxide salt, or a combination thereof can be used. More specifically, the water-soluble metal compound is Ag 2 CO 3, Ag (NH 3) 2, AgNO 2, AgNO 3, AgCl, AgClO 4, AgClO 3, AgCOOCCH 3, H 3 AsO 4, AuCl, AuCl 3, AuCl 4 H 4 N, HAuCl 4, KAuCl 4, KAuBr 4, CdSO 4, Co ( NH3) 6, Cu (NH3) 4, CuSO4, Ni (NH3) 6, Pb (NO3) 2, PbSO4, Pd (NO3) 2, PdCl2 2H2O, (CH4) 2PdCl6, PdCl2, Pd (NH3) 4Cl2, Pd ( NH3) 2 (NO2) 2, PtCl2, PtCl4, Pt (CN) 2, Pt (NH3) 2Cl4, H2PtCl6 · 6H2O, SnCl2, SnCl4, SnBr2, Zn (NH3) 4, ZrO (NO3) 2, (NH3) 2Pt (NO2) 2, PtCl2 (C6H5CN) 2, PtCl2 (C5H5N) 2, Sn (CH3COCHCOCH3) 2, Sn (CH3) 4, (CH3) 2SnCl2, RhX3, RhX3? nH2O, Rh2 (CO) 4X2, where X is a halide such as Cl-, Br- or I-), RuCl3? nH 2 O, Ru (NO) (NO 3) 3 or a combination thereof may be used.

Another example of the water-soluble metal compound may be a waste containing non-ferrous metals such as waste catalyst, waste scrap, waste batteries, industrial waste liquid, converter dust, and waste cans containing valuable metals.

Industrial wastes containing valuable metals occur mainly in industries that use valuable metals as catalysts in the chemical process and in the electrical and electronics industry. In particular, the wastewater generated in the wastewater generated in the chemical plant contains ruthenium (Ru) and iridium (Ir), and the ICP analysis wastewater contains various valuable metal species (especially platinum and rhodium). .

In the above reaction, there is no particular limitation on the mixing ratio of the biomass and the water-soluble metal compound. As an example, the biomass 1g / L ~ 100g / L can be mixed in 100mg / L ~ 1000mg / L of a water-soluble metal compound.

The biomass can be used in the form of finely divided granules.

The biomass extract may be used by putting the biomass in a solvent such as water or the like while being heated or unheated.

The method can control the adsorption rate by changing the pH, reaction temperature, initial metal ion content in the mixture.

For example, when the metal ion is a cation in the adsorption step, the pH range in the mixture can be adjusted to 5 to 10.

Metal nanoparticles  Creation stage

The step is to reduce the metal ions adsorbed on the surface of the bacterial biomass to the bacterial biomass to generate metal nanoparticles.

The step may reduce the metal ions adsorbed on the bacterial biomass surface to the bacterial biomass. That is, the metal ions are reduced to nanoparticles by the reducing substances present in or on the surface of the biomass even without additional chemicals such as reducing agents or auxiliary agents added to the mixture.

Reducing material, which is a term used in the present invention, is a material existing on or inside a biomass, and may reduce metal ions to generate zero-valent metal particles. The reducing material may represent an active functional group that allows metal ions to propagate through the cell membrane, and more broadly, may be used as a term encompassing a physicochemical mechanism for reducing metal ions by such functional groups. Examples of such functional groups include enzymes, organics, inorganics, and other metabolites. More specifically, examples of the reducing material may be an amine group, amino group, carboxyl group, phosphoric acid group, sulfonic acid group or hydroxyl group present on the surface or inside of the bacterial biomass, or a carboxyl group introduced to such biomass surface. It may be a compound or a polymer containing a large amount of phosphoric acid group, sulfonic acid group, hydroxyl group, amine group, preferably an amine group-containing cationic polymer crosslinked on the surface of bacterial biomass.

In the metal nanoparticle generation step, the reduction reaction proceeds at the same time as the mixture is adsorbed, and the metal nanoparticles begin to be produced, and after the reduction reaction is reached for about 48 hours, preferably 24 hours after the adsorption equilibrium is reached. It happens mainly.

Even before the adsorption reaction of the mixture reaches an equilibrium, a small amount of metal nanoparticles may be produced, and most metal nanoparticles are produced after a high concentration of metal ions are adsorbed on the biomass to reach an adsorption equilibrium. According to the present invention, metal nanoparticles can be obtained by maintaining the mixture for about 48 hours after equilibrium of adsorption.

In the present invention, the activated bacterial biomass and the sterilized inactivated biomass can be used, but the reduction mechanism is somewhat different. 2 is a TEM image of the activated bacterial biomass and the inactivated biomass surface after the metal nanoparticle generation step. Referring to FIG. 2, nanoparticles are hardly generated on the activated bacterial biomass surface, but a large amount of metal nanoparticles are generated on the inactivated bacterial biomass surface. Inactivated bacterial biomass causes functional groups (eg, organic groups) present inside the cell to be released into the cell surface or solution by rupture of active cells during high temperature autoclave, thus inactivating bacterial biomass. The mass is believed to have more reducing material on the cell surface, and more actively produce metal nanoparticles on the cell surface than on the activated biomass.

In the present invention, since metal ions are reduced by adsorption of metal ions through biomass and reducing substances present on the surface or inside of biomass, metal nanoparticles are not eco-friendly, economical and harmless to humans without using chemicals such as reducing agents. Particles can be prepared.

The metal nanoparticle generation step may control the production rate or size of the metal nanoparticles by adding an auxiliary agent to the mixture. The adjuvant is a compound that promotes the formation of metal nanoparticles, or when the reaction proceeds to a certain extent and the metal nanoparticles are produced in a desired size and shape, the counter ions that surround the metal nanoparticles to terminate the reaction (counter) Preference is given to compounds which can provide ions).

As the adjuvant, halide material, nitrate, sulfate, phosphate may be used.

The adjuvant may be at least one selected from the group of KCl, NaCl, NaBr, KF, KI, KBr, NaNO3, KNO3, Na2SO4, NaH2PO4, KH2PO4.

In order to control the size of the metal nanoparticles, the reduction rate of the metal nanoparticles can be controlled by the reaction temperature, the reaction pH, and the concentration of the reaction time. When the reduction rate of the metal ions is slow, the metal ions adhere to the reduced metal and thus the reduction is made, thereby increasing the size of the metal nanoparticles. On the other hand, if the reduction rate of the metal ions is fast, the metal ions themselves are rapidly reduced, so that the size of the metal nanoparticles is small and mainly spherical. Therefore, the size of the metal nanoparticles can be controlled by increasing the reaction conditions, that is, increasing the reaction temperature, or increasing the adsorption equilibrium concentration in order to increase the reduction rate of the metal ions.

In another aspect, the present invention relates to metal nanoparticles prepared by the above method. The metal nanoparticles may range in size from 5 to 100 nm.

Hereinafter, the present invention will be described in more detail with reference to examples, but these are merely to illustrate preferred embodiments of the present invention, and the examples do not limit the scope of the present invention.

Example  One

Microorganisms ( Corynebacterium After culturing glutamicum ), the microbial culture was centrifuged to separate cells. Subsequently, three times washing with distilled water (DW) was carried out to remove the media components of the separated cell surface, followed by centrifugation to obtain activated biomass cells. Subsequently, some of the activated cells were sterilized at 120 ° C. and 15 min using an autoclave to obtain inactivated biomass cells.

Subsequently, 0.2 g (medium free cell pellet) of activated biomass cells and inactivated biomass cells were added to 20 ml of 100 mg / L water-soluble metal compound (silver nitrate, AgNO3) and stirred at 160 rpm, 30 ° C. and 24 hours for silver ions. Was adsorbed (adsorption rate experiment results are shown in FIG. 3). Subsequently, the mixture was stirred at 160 rpm, 30 ° C., and 72 hours to produce silver nanoparticles. After 72 hours of silver ion adsorption, TEM, UV-vis, and XRD were analyzed and shown in FIGS. 2, 4, and 5, respectively.

Example  2

Corynebacterium glutamicum biomass, a fermentation waste obtained in the form of a dried powder from the fermentation process (C. glutamicum 50 g of biomass) (subjective Gunsan Plant, Gunsan, Jeonbuk) was added to 500 mL of water containing 10% (W / V) polyethyleneimide (PEI) and stirred at room temperature for about 24 hours. After the reaction was completed, solid-liquid separation was performed to collect only the biomass and put it back in a 500 ml solution of 1% (V / V) glutaraldehyde and stirred at room temperature. After the reaction was completed, washed several times with deionized water and then lyophilized to obtain a surface-modified biomass (PEIB).

Meanwhile, as in Example 1, Corynebacterium glutamicum, which is a fermentation waste from the subject, was washed three times using distilled water (D.W), and then centrifuged and dried to obtain biomass (RB).

Experiment 1 Experiment by Metal Concentration

158 ppm ~ 520 ppm HAuCl ₄ 0.09 g of biomass (PEIB, RB) was added to 90 mL of each metal concentration, and the maximum adsorption amount of each metal ion concentration was analyzed and shown in FIG. 6. The produced metal nanoparticles were obtained after 24 hours. Analysis by TEM is shown in FIG. 7.

Experiment 2 Reduction Rate Experiment

270 ppm HAuCl ₄ 0.03 g biomass (PEIB, RB) was added to 30 ml, and the adsorption amount of metal ions was analyzed by time, and is shown in FIG.

Figure 3 shows the amount of silver ions adsorption according to the adsorption time in Example 1. Referring to FIG. 3, both the activated biomass 3a and the inactivated biomass 3b were quickly adsorbed, and the maximum adsorption amount of each microorganism was 43.27 mg / g and 47.13 mg / g. Referring to Figure 3, it can be seen that within 30 minutes the metal ion is rapidly adsorbed to the biomass.

4 is a UV-vis spectrum for identifying silver nanoparticles produced by Example 1. FIG. Referring to FIG. 4, it can be seen that the silver nanoparticles are generated because the peak increases in the 420-440 nm region. Inactivated biomass (b) shows a higher value than biomass (a) activated at UV peak because the color is more intense when the biomass itself is turbid in water.

FIG. 2 is a photograph taken by transmission electron microscopy (TEM) of the silver nanoparticle image generated by Example 1. FIG. Referring to FIG. 2, both activated biomass (a) and inactivated biomass (b) generated silver nanoparticles, but more metal nanoparticles were generated on the inactivated biomass surface.

Figure 5 is an analysis of the X-ray diffraction (XRD) pattern of the silver nanoparticles produced by Example 1. Referring to FIG. 5, the deactivated biomass (5b) is cubic phases (38.7 (111), 44.5 (200) and 64.1 (220)), and the activated biomass (5a) is silver chloride nanoparticles with cubic phases (27.8). (111), 32 (200), 46 (220) and 54.5 (222)) patterns.

FIG. 6 is a graph illustrating the maximum adsorption amount of each metal ion concentration of PEIB and RB, and FIG. 7 is a graph illustrating analysis of the metal nanoparticles generated in Experimental Example 1 by TEM after 24 hours. Referring to FIG. 6, when the concentration of metal ions is 158 ppm, RB adsorbs more than PEIB, but as the concentration of metal ions increases, PEIB adsorbs and reduces more than RB. Referring to FIG. 7, the metal nanoparticle size of the low concentration is small, and as the metal ion concentration increases, the size increases. In particular, in the case of metal nanoparticles made using PEIB, it can be seen that the size change is obvious.

FIG. 8 is a graph illustrating analysis of metal ion adsorption amount of PEIB and RB over time, and FIG. 9 is a TEM image of an image of reduced metal nanoparticles analyzed over time. Referring to FIG. 8, in the case of RB, about 5 minutes after the adsorption of metal ions, metal nanoparticles are generated, and in the case of PEIB, the reduction is performed at the same time as the adsorption of metal ions. After 1 minute of adding the PEIB to the metal ion solution, metal nanoparticles of 1 to 2 nm were seen, and after 1 hour, the size of the metal nanoparticles was increased.

Although the above has been described in detail with reference to a preferred embodiment of the present invention, this description is merely to describe and disclose an exemplary embodiment of the present invention. Those skilled in the art will readily recognize that various changes, modifications and variations can be made from the above description and the accompanying drawings without departing from the scope and spirit of the invention.

Claims (15)

Agitating a mixture of the water-soluble metal compound and the sterilized inactivated bacterial biomass to adsorb metal ions onto the bacterial biomass surface; And
And maintaining the bacterial biomass in the water-soluble metal compound after the adsorption equilibrium of the metal ions is reached to generate metal nanoparticles.  The method of claim 1, wherein the producing of the metal nanoparticles comprises reducing material present in or on the surface of the bacterial biomass to reduce the metal ions.  The method of claim 2, wherein the reducing material is an amine group, amino group, carboxyl group, phosphoric acid group, sulfonic acid group or hydroxyl group present on the surface or inside of the bacterial biomass, or a carboxyl group, phosphoric acid group, sulfonic acid introduced on the surface of the biomass. Method for producing a metal nanoparticles, characterized in that the compound containing a group, a hydroxyl group or an amine group.  The method of claim 1, wherein the producing of the metal nanoparticles comprises maintaining the bacterial biomass in the water-soluble metal compound for 48 hours. delete delete  The method of claim 1, wherein the inactivated bacterial biomass is heat sterilized so that the reducing material therein is released to the surface of the bacterial biomass.  The method of claim 1, wherein the adsorption step of adjusting the pH range of the mixture to 5 to 10 when the metal ion is a cation. delete The method of claim 1, wherein the water-soluble metal compound is Ag2CO3, Ag (NH3) 2, AgNO2, AgNO3, AgCl, AgClO4, AgClO3, AgCOOCCH3, H3AsO4, AuCl, AuCl3, AuCl4H4N, HAuCl4, KAuCl4, KAuBr4, CdSO4, Co (NH3) ) 6, Cu (NH3) 4, CuSO4, Ni (NH3) 6, Pb (NO3) 2, PbSO4, Pd (NO3) 2, PdCl2 2H2O, (CH4) 2PdCl6, PdCl2, Pd (NH3) 4Cl2, Pd (NH3) 2 (NO2) 2, PtCl2, PtCl4, Pt (CN) 2, Pt (NH3) 2Cl4, H2PtCl6, 6H2O, SnCl2, SnCl4, SnBr2, Zn (NH3) 4, ZrO (NO3) 2, (NH3) 2Pt ( NO2) 2, PtCl2 (C6H5CN) 2, PtCl2 (C5H5N) 2, Sn (CH3COCHCOCH3) 2, Sn (CH3) 4, (CH3) 2SnCl2, RhX3, RhX3? nH2O, Rh2 (CO) 4X2, where X is a halide such as Cl-, Br- or I-), RuCl3? nH 2 O, Ru (NO) (NO 3) 3 or a method for producing a metal nanoparticles, characterized in that at least one selected from the group consisting of.  The method of claim 1, wherein the mixture is a mixture of 1 g / L to 100 g / L of the biomass and 100 mg / L to 1000 mg / L of a water-soluble metal compound.  The method of claim 1, wherein the bacterial biomass is Corynebacterium ammonia genes (Corynebacterium ammoniagenes), Corynebacterium glutamicum (Escherichia coli), Bacillus megaterium (Bacillus) megatherium) and at least one selected from the group consisting of Serratia marcescens and Brevibacterium ammoniagenes, wherein the surface of the bacterial biomass is an amine group, amino group, carboxyl group, or phosphate group. Method for producing metal nanoparticles, characterized in that the surface-modified to at least one selected from the group of compounds containing sulfonic acid groups and hydroxyl groups. The method of claim 1, wherein the bacterial biomass comprises an amine group-containing cationic polymer crosslinked on its surface, the amine group-containing cationic polymer is polyethyleneimine, amine-terminated polyethylene oxide, amine-terminus Naked polyethylene / propylene oxide, polymer of dimethyl amino ethyl methacrylate and copolymer of dimethyl aminoethyl methacrylate and vinylpyrrolidone, linear polymer of epichlorohydrin and dimethylamine, polydiallyldimethylammonium chloride, Method for producing metal nanoparticles, characterized in that it is selected from the group consisting of polyethanolamine / methyl chloride and modified polyethyleneimine.  2. The method of claim 1, wherein the method adds an adjuvant which is one of a halide material, nitrate, sulfate or phosphate to the metal nanoparticle production step. The nanoparticles prepared according to any one of claims 1 to 4, 7, 8 and 10 to 14, wherein the size of the nanoparticles is a metal, characterized in that 5 ~ 100nm Nanoparticles.

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