KR20160080946A - Eco-friendly Method for producing of silica using fermented solution) - Google Patents

Abstract

The present invention relates to a method for producing silica environmentally friendly from biomasses using a microorganism fermented broth, and specifically, to a method for producing silica environmentally friendly comprising: a step of mixing biomasses with a microorganism fermented broth to prepare a mixed solution, and then treating the mixed solution at high temperatures and pressures; a step of separating a filtrate from the mixed solution treated at the high temperatures and pressures, and cleaning the separated filtrate; and heat-treating the cleaned filtrate. A method for producing silica environmentally friendly using a microorganism fermented broth according to the present invention is capable of efficiently producing silica from various biomasses using the microorganism fermented broth only without using harmful synthetic materials.

Description

TECHNICAL FIELD [0001] The present invention relates to a method for producing an eco-friendly silica using a microbial fermentation broth,

The present invention relates to a method for producing silica in an environmentally friendly manner using a microbial fermentation broth, and more particularly, to a method for producing environmentally friendly silica by mixing a biomass and a fermentation broth with a microbial fermentation broth followed by high temperature and high pressure treatment, separating the filtrate from the high- Washing the washed filtrate, and heat treating the washed filtrate. According to the present invention, it is possible to efficiently produce silica from various biomass using only the microbial fermentation broth without using harmful synthetic materials.

A large amount of silica is present in the biomass, especially in the leucrose-based biomass, and is known to contain about 10% by weight of silica, especially in rice hulls and rice straw.

These biomass-derived silicas can be prepared from silicon raw materials (JAAmick, J. Electrochem. Soc. 129, 864 (1982); LPHunt, J. Electrochem. Soc. 131, 1683 (Am. Chem. Soc., 74, 2869 (1991)), and cement additives (Jose James, et.al, J. Sci. Ind. Res. 51, 383 (1992)).

On the other hand, in order to obtain silica from biomass, research on the development of techniques for removing organic materials (biomass, cellulose, hemicellulose, lignin, etc.) of biomass has been continuously carried out. Typically, rice husk or rice straw is treated with acid, A method of obtaining silica has been used.

However, these conventional methods only focus on the production of silica. In addition to using harmful substances such as strong acids, it is difficult to control the structure of produced silica, that is, the pore size and the pore size, There was a limit to commercialization.

Accordingly, the present invention provides a process for producing an environmentally friendly silica which can easily produce high purity silica from a biomass without using a toxic substance such as a strong acid and can easily control the structure of produced silica, that is, .

In order to accomplish the above object, the present invention provides a method for producing a microbial fermentation product, comprising mixing a biomass and a microbial fermentation broth, Separating and washing the filtrate from the high-temperature high-pressure treated mixed solution; And heat treating the washed filtrate. The present invention also provides a method for producing environmentally-friendly silica using the microbial fermentation broth.

The microbial fermentation broth may be a fermentation broth of phytopathogenic fungi or saprophytic fungus. Preferably, the microbial fermentation broth is a cytoplasmic enzyme, and the fungus including oxaloacetate hydolase Is preferably used. At this time, it is preferable that the fungus is cultured under a condition of pH 5 to 6 using hexose as a carbon source.

The high-temperature and high-pressure treatment may be performed by mixing 0.5 to 2 L of the fermentation broth with 100 g of biomass per 100 g of biomass, and then performing the reaction at 120 to 200 ° C under 1 to 5 atm for 1 to 5 hours in a carbon dioxide atmosphere And the heat treatment after washing can be performed at 700 to 1,000 ° C for 3 to 5 days.

In another embodiment, the high-temperature and high-pressure treatment may be performed by mixing 0.5 to 2 L of the fermentation broth of microorganism per 100 g of biomass, and then conducting the reaction in air atmosphere at 120 to 200 ° C and 250 to 1,200 atm for 30 minutes to 2 hours And the heat treatment after the washing may be performed at 700 to 1,000 ° C for 1 to 3 days.

On the other hand, the biomass is preferably lignin cellulose biomass such as rice bran, rice husk, rice straw, reed, corn leaf and stem.

The silica production method of the present invention can produce high purity silica having a high specific surface area from biomass using only environmentally friendly microbial fermentation liquid without using any harmful substances such as strong acids.

Figs. 1A and 1B are photographs showing the difference between before and after pyrolysis according to Example 1 of the present invention
2 - TEM (transmission electron microscope) photograph of silica prepared according to Example 1 of the present invention
3A and 3B, BET data of silica prepared according to Example 1 of the present invention
4A and 4B are photographs showing the difference between before and after pyrolysis according to Example 2 of the present invention
5a, b - BET data of silica prepared according to Example 2 of the present invention
6A and 6B are photographs showing the difference before and after pyrolysis according to the comparative example of the present invention
Figure 7 - BET data of silica prepared according to the comparative example of the present invention

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. Prior to the description, terms and words used in the present specification and claims should not be construed as limited to ordinary or dictionary meanings and should be construed in accordance with the technical concept of the present invention.

Throughout this specification, when an element is referred to as "including" an element, it is understood that it may include other elements as well, without departing from the other elements unless specifically stated otherwise. In addition, the steps described in the present invention can be carried out in a different order than those described in the specification unless clearly specified in the context.

The method for producing silica according to the present invention comprises mixing a biomass and a microbial fermentation broth and then subjecting the mixture to high temperature and high pressure treatment; Separating and washing the filtrate from the high-temperature high-pressure treated mixed solution; And heat treating the washed filtrate. Let's take a closer look at each step below.

First, the biomass containing silica is mixed with the fermentation broth of the microorganism and treated at a high temperature and a high pressure to remove the organic matter of the biomass.

At this time, the biomass may be various kinds of biomass containing silica, but preferably lignin cellulose biomass such as rice bran, rice husk, rice straw, reed, corn leaf and stem showing a high silica content is used .

Meanwhile, the microbial fermentation broth is preferably a fermentation broth of a phytopathogenic fungus or saprophytic fungus. In the case of the phytopathogenic fungus or fungus fungus, various active ingredients capable of decomposing plant cell walls . ≪ / RTI >

In particular, in the case of a tree root fungus containing cytoplasmic enzyme oxaloacetate hydolase, the hydrolytic enzyme may be added to the cellulosic, hemicellulose, lignin or the like, such as oxalic acid, And the like, thereby further promoting the removal of impurities from the biomass.

These bio-derived components are more environmentally friendly than the use of harmful synthetic materials such as strong acids, and decomposition of biomass is performed under milder conditions. Therefore, the structure of silica produced by controlling the synthesis conditions such as heat treatment temperature and time It is easy to control.

Various types of fungi having oxaloacetate hydolase may be used. In one embodiment, Aspergillus niger , Paxillus involutus and the like can be used.

At this time, in order to increase the decomposition efficiency of cellulose, hemicellulose, lignin and other organic substances, it is preferable that the fungus is cultured under a condition of pH 5 to 6 using hexose as a carbon source.

When the biomass and the microbial fermentation broth are prepared, the biomass is mixed with the microbial fermentation broth and then subjected to a high-temperature and high-pressure pretreatment in order to remove the organic matter. In this case, And the reaction is carried out under a carbon dioxide atmosphere at 120 to 200 ° C and 1 to 5 atm for 1 to 5 hours. In this case, the heat treatment is carried out at 700 to 1,000 ° C. for 3 to 5 days .

In another embodiment, the high-temperature and high-pressure treatment may be performed by mixing 0.5 to 2 L of the fermentation broth of microorganism per 100 g of biomass, and then conducting the reaction in air atmosphere at 120 to 200 ° C and 250 to 1,200 atm for 30 minutes to 2 hours In this case, the post-cleaning heat treatment can be performed at 700 to 1,000 ° C for 1 to 3 days.

The mixed solution having been subjected to the high-temperature high-pressure treatment is subjected to a washing process after separating the filtrate through a filter or the like. The washing process is preferably performed until hot water and clear water come out of the fermentation broth so that all of the components of the fermentation broth can be removed. However, the present invention is not limited thereto, and organic matter (ethanol, methanol) may be used as the washing solution.

The washed filtrate is subjected to heat treatment for final thermal decomposition of carbon components such as cellulose, hemicellulose, and lignin and other residues. The heat treatment may vary depending on high temperature and high pressure treatment conditions as described above, Specifically, it may be carried out at a temperature of 700 to 1,000 DEG C for 1 to 3 days or for 3 to 5 days. The thus prepared silica exhibits a high purity of 95% or more.

Hereinafter, the effects of the present invention will be described in detail through examples of the silica production method of the present invention. However, these embodiments are intended to illustrate one or more embodiments, and the scope of the invention is not limited to these embodiments.

[Example 1]

1) Aspergillus niger was cultured under pH 6 with sugar as a carbon source, and the fermentation broth was isolated. 20 g of rice husk was added to 200 mL of the above fermentation broth, and the mixture was reacted at 200 psi with CO ₂ at 200 캜 for 3 hours. Then, the mixture was washed with hot water until a clear color appeared in the Vaccum filter. Thereafter, the washed slurry was transferred to a crucible and thermally decomposed at 800 ° C. for 96 hours to finally produce silica. FIGS. 1A and 1B are photographs showing the difference between before and after pyrolysis. It can be seen that the carbon component and the like are removed through the pyrolysis process.

2) TEM photograph and BET data of the silica prepared according to Example 1 are shown in FIG. 2 and FIG. 3, and the total surface area, mass change and ICP component data are shown in Tables 1 and 2 below.

Surface area (m 2 / g) Pore volume (cm < 3 > / g) Pore size (nm) 70.5768 0.206229 107.067 Initial biomass mass (g) Mass after pyrolysis (g) percentage(%) 40 4.723 12

Analysis item Analysis SO2 95.8362 Al2O3 0.094679 CaO 1.420185 MgO 0.357676 Na2O 0.01052 MNO 0.063119 P2O5 0.115719 NiO 0.610154 ZnO 0.03156 CuO 0.03156 Cr2O3 1.325506 S 0.02104 C 0.04208 Total amount 99.96

As can be seen from the above data, high purity (over 95%) silica having an average pore size of about 100 nm and a specific surface area of about 70 / g could be produced.

[Example 2]

1) Aspergillus niger was cultured under pH 6 with sugar as a carbon source, and the fermentation broth was isolated. 60 g of rice husk was added to 600 mL of the above fermentation broth and autoclaved at 121 ° C and 250 to 1,200atm pressure for 1 hour, followed by washing with hot water to obtain a clear color in a Vaccum filter. Thereafter, the washed slurry was transferred to a crucible and thermally decomposed at 800 ° C for 48 hours to finally produce silica. FIGS. 4A and 4B are photographs showing the difference between before and after pyrolysis. It can be confirmed that carbon components and impurities are removed through pyrolysis.

2) BET data of the silica prepared according to Example 2 is shown in Figs. 5A and 5B, and the total surface area, mass change and ICP component data are shown in Tables 3 and 4 below.

Surface area (m 2 / g) Pore volume (cm < 3 > / g) Pore size (nm) 50.0135 0.124953 8.5755 Initial biomass mass (g) Mass after pyrolysis (g) percentage(%) 60 6.8976 11

Analysis item Analysis SiO2 97.30 Al2O3 0.05 FeO3 0.02 CaO 2.36 MgO 0.03 Na2O 0.03 K2O 0.02 MnO 0.02 P2O5 0.07 Li2O 0.03 S 0.01 C 0.01 Total amount 99.95

As can be seen from the above data, the autoclave was able to reduce the reaction time by half or more, and had high purity (97% or more) silica having an average pore size of about 8 nm and a specific surface area of about 50 g / .

[Comparative Example]

20 g of rice husk was pyrolyzed immediately at 800 ° C for 72 hours without treatment with microbial fermentation broth to produce silica. 6A and 6B are photographs showing the difference between before and after pyrolysis, and it can be seen that the shape of the rice hull was maintained almost even after pyrolysis. BET data of the silica prepared according to the comparative example are shown in Fig. 7, and the total surface area, mass change and ICP component data are shown in Tables 5 and 6 below.

Surface area (m 2 / g) Pore volume (cm < 3 > / g) Pore size (nm) 1.2091 0.001019 57.382 Initial biomass mass (g) Mass after pyrolysis (g) percentage(%) 20 2.3461 12

Analysis item Analysis SiO2 94.70 Al2O3 0.08 Fe2O3 0.06 CaO 1.42 MgO 0.54 Na2O 0.09 K2O 1.70 MnO 0.18 P2O5 1.14 ZnO 0.02 S 0.07 C 0.04 Total amount 100.04

As can be seen from the above data, when the microbial fermentation broth was not treated at high temperature and high pressure, it was confirmed that the specific surface area was very small as compared with the examples.

The present invention is not limited to the above-described specific embodiments and descriptions, and various modifications can be made to those skilled in the art without departing from the gist of the present invention claimed in the claims. And such modifications are within the scope of protection of the present invention.

Claims (9)

Mixing the biomass with the microbial fermentation broth, and then subjecting the mixture to high temperature and high pressure;
Separating and washing the filtrate from the high-temperature high-pressure treated mixed solution; And
Heat treating the washed filtrate;
Wherein the microbial fermentation broth is a microbial fermentation broth. The method according to claim 1,
Wherein the microbial fermentation broth is a phytopathogenic fungus or a saprophytic fungus fermentation broth. 3. The method of claim 2,
Wherein the fungus is a cytoplasmic enzyme and is a tree root fungus including oxaloacetate hydolase. The method of claim 1, wherein the fungus is a cytoplasmic enzyme. The method of claim 3,
Wherein the fungus is cultured under a condition of pH 5 to 6 using hexose as a carbon source. ≪ RTI ID = 0.0 > 8. < / RTI > The method according to claim 1,
Wherein the high temperature and high pressure treatment is performed by mixing 0.5 to 2 L of the microbial fermentation broth per 100 g of the biomass and then performing the reaction for 1 to 5 hours at 120 to 200 캜 and 1 to 5 atm under a carbon dioxide atmosphere. A method for manufacturing an environmentally friendly silica. 6. The method of claim 5,
Wherein the heat treatment is performed at 700-1,000 DEG C for 3-5 days. The method according to claim 1,
Wherein the high temperature and high pressure treatment is carried out by mixing 0.5 to 2 L of the microbial fermentation broth per 100 g of the biomass and then performing the reaction for 30 minutes to 2 hours under the reaction conditions of 120 to 200 DEG C and 250 to 1,200 atm in the air atmosphere. (Method for manufacturing environmentally friendly silica using fermentation liquid). 8. The method of claim 7,
Wherein the heat treatment is performed at 700 to 1,000 DEG C for 1 to 3 days. The method according to claim 1,
Wherein the biomass is a lignin cellulose-based biomass.

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