JP2006281042A - Continuous porous molded body immobilizing microbe and method for discoloring dye using this - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a dye discoloring carrier which is not conventionally present and has capacity by contriving a continuous porous molded body which highly efficiently immobilizes a safe microbe without adversely affecting the human body. <P>SOLUTION: By immobilizing a large quantity of Basidiomycetes on the continuous porous molded body, the dye discoloring carrier is obtained which is not conventionally present, is safe and has capacity. Particularly, it is preferable to immobilize Basidiomycetes such as Coriolus hirsutus on the crushed continuous porous molded body containing ash of rice hull. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention is a technique related to decolorization of a dye using a continuous porous molded body in which microorganisms having high decolorization property with respect to the dye are immobilized with high efficiency.

  The waste liquid discharged from the process of handling the dye contains various dyes and is often hardly decomposable. Examples of methods for colorless treatment of these colored waste liquids include adsorption, filtration, coagulation sedimentation, and chemical decomposition, but their effects are limited, and the total cost, including the treatment costs for sludge, is rather expensive. This is a colorless process.

  Further, as a method that replaces the above method, a treatment method using microorganisms has attracted attention, and some fungi that have already decomposed and become colorless have been reported. These methods have less secondary problems than the physicochemical methods and are being studied as cost-effective methods. However, in the treatment method with microorganisms, the ability of the bacteria to decolorize is weak, and the specificity in the relationship between the bacteria and the dye to be treated is recognized, and further, the treatment efficiency is improved and a versatile method is desired.

  In order to improve these problems, Patent Document 1 discloses a technique for screening bacteria that decolorize dyes and isolating new strains of filamentous fungi having high decoloring activity for various dyes.

  Moreover, in patent document 2, the technique which paid its attention to the microbe which decolorizes and decomposes | disassembles the azo dye contained in many colored wastewater is disclosed.

JP-A-9-173051 JP2003-334588

  However, in the above method, the problem of safety still remains, and the object of the present invention is to provide a continuous porous molded body in which microorganisms having high decolorization properties that do not adversely affect the human body are immobilized with high efficiency. It is an object of the present invention to provide a carrier for dye decolorization which has an unprecedented processing capability.

  The present invention has found that a dye-decolorizing carrier having an unprecedented processing ability can be obtained by immobilizing basidiomycetes in a large amount on a continuous porous molded body, and has led to the present invention. In order to achieve the above object, the present invention provides the following means.

  [1] A dye decolorizing carrier, wherein at least one or a plurality of bacteria are immobilized on a continuous porous molded body, and the dyeing solution and the bacteria are brought into contact with each other for decolorization.

  [2] The dye decolorizing carrier according to item 1 above, wherein the continuous porous molded body is obtained by crushing a continuous porous molded body containing rice husk ash.

  [3] The continuous porous molded body is obtained by pulverizing a continuous porous molded body containing one or more binders selected from the group consisting of cement and gypsum, rice husk ash and inorganic aggregate. 3. The dye decolorizing carrier according to item 1 or 2 above.

  [4] The dye decolorizing carrier according to any one of items 1 to 3, wherein the continuous porous molded body is obtained by crushing the continuous porous molded body so that the particle diameter is 0.5 mm to 5 mm.

  [5] For dye decolorization according to any one of the preceding items 1 to 4, wherein at least one or more basidiomycetes selected from the group of basidiomycetes of Arakawakawatake, Kawaratake, shiitake, and oyster mushrooms are immobilized on a continuous porous molded body. Carrier.

  [6] A method for decolorizing a dye with the dye decolorizing carrier according to any one of items 1 to 5

  According to the invention of [1], since the carrier is a continuous porous molded body, it is possible to immobilize a large number of bacteria capable of dye decolorization, and decoloration is caused by contacting the dye solution and the bacteria. A carrier for dye decolorization that is excellent in durability and rich in decoloring power can be obtained.

  According to the invention of [2], the continuous porous molded body is obtained by pulverizing the continuous porous molded body containing rice husk ash, and is thus formed due to the unique shape of rice husk ash. Since a continuous porous structure is ensured and it is lightweight and can provide a suitable growth environment for bacteria and microorganisms, a carrier for dye decolorization having an excellent decolorizing power can be obtained. In addition, rice husk ash, which has not been used and is often discarded in the past, is one of the main raw materials, so that resources can be effectively used and environmental conservation can be achieved.

  According to the invention of [3], the continuous porous molded body contains one or more binders selected from the group consisting of cement and gypsum, rice husk ash and inorganic aggregate, so After that, sufficient strength as a continuous porous molded body can be obtained.

  According to the invention of [4], the continuous porous molded body is obtained by finely pulverizing the continuous porous molded body so that the particle diameter is 0.5 mm to 5 mm, and therefore, more bacteria are immobilized. It is possible to increase the contact area with the dye and to provide a dye-decolorizing carrier having a stronger decolorizing power.

  According to the invention of [5], since the bacterium is at least one or a plurality of basidiomycetes selected from the group of basidiomycete, agaricus mushrooms, shiitake mushrooms, and oyster mushrooms, it is used for dye decolorization having a stronger decolorizing power It can be a carrier.

  The invention of [6] is a method in which an excellent dye decolorization function is exhibited because bacteria and microorganisms are fixed not only on the surface but also on an internal continuous porous structure.

  The present invention is to decolorize the bacteria having the ability to decolorize the dye by allowing the dye to pass through the continuous porous molded body by fixing the bacteria having the ability to decolorize the dye and bringing the dye into contact with the dye. is there. Although it does not specifically limit as a microbe which has the capability to decolorize a dye, The basidiomycete of Aragekawaratake, Kawaratake, Shiitake, and Oyster mushroom is suitable. Among these, Aragekawaratake is superior in its ability to decolorize many types of dyes and is more suitable.

  Basidiomycetes are well known as fungi that decay wood in nature. When basidiomycete spores fall on wood, they germinate and become hyphae, and grow from sugar and starch in the wood as nutrients, followed by cellulose and hemicellulose. The wood that decomposes to lignin and is nourished by basidiomycetes becomes crumbly and returns to the soil. A basidiomycete (wood decaying fungus) that changes to white when wood decays is called white decaying fungus. The white rot fungus is said to secrete hydrogen peroxide and peroxidase (a powerful oxidase) outside the cells and decompose the pigment. Examples include enoki mushrooms, oyster mushrooms, and shirohirotake. Alagekawaratake is a mushroom belonging to the family Sarnococcidae that is widely distributed worldwide and consists of many white-rot fungi and is more suitable for the present invention.

  Although the mechanism of the present invention has not been fully elucidated, it is considered that the enzyme is secreted by the enzyme secreted by the basidiomycete, and a large amount of this decolorizing enzyme is extracted from the basidiomycete, and the enzyme and the dye are combined. It is important to increase the chance of contact. In order to fix the basidiomycetes to the continuous porous molded body, first, the basidiomycetes are cultured in a liquid PD medium at an appropriate temperature. A preferable temperature is 15 to 50 ° C., and the cells are cultured for several days. Next, a continuous porous molded body is put into this basidiomycete culture solution and further cultured for several days.

  After several days, the continuous porous molded body is taken out and placed in a column and cultured for several days. By doing so, basidiomycetes are firmly immobilized on the surface and inside of the continuous porous molded body.

  The continuous porous molded body used in the present invention is preferably a continuous porous molded body containing rice husk ash. Furthermore, a crushed continuous porous molded body is preferable. As rice husk ash, any ash can be used as long as it is obtained by burning rice husk obtained by milling rice. Although the color tone and crystal form of rice husk ash vary depending on the atmosphere at the time of burning, the firing temperature, and the firing time, any of these can be used.

  One or more binders selected from the group consisting of cement and gypsum may be used as the binder for the continuous porous molded body. Any kind of cement may be used, but Portland cement is preferably used. Also, the gypsum is not particularly limited. The strength of the obtained porous body can be ensured by the hydration reaction between these binders and rice husk ash.

  The inorganic aggregate is a component used for improving the strength of the porous body. The inorganic aggregate is not particularly limited, and examples thereof include silica, silicon sand, mountain sand, sea sand, silicate and the like mainly composed of silicon dioxide. Examples of the silicate include clay, diatomaceous earth, zeolite, feldspar, and fly ash. Among these, it is preferable to use silica stone or silicate because the strength of the porous body can be further improved. Particularly preferred is a configuration using silica stone, which can further improve the strength of the porous body.

  The continuous porous molded body in the present invention is preferably one obtained by finely crushing the continuous porous molded body so that the particle diameter is 0.5 mm to 5 mm. By crushing, a porous molded body with more surface pores exposed to the outside can be obtained, and since the particle size is 0.5 mm to 5 mm, many basidiomycetes are immobilized on the continuous porous molded body. Can do.

  Next, the present invention will be described specifically by way of examples. In the examples, the dye decolorization ability was measured by collecting various dye solutions at regular intervals and measuring the absorbance to obtain the color decoloration rate.

<Example 1>
A continuous porous molded body obtained by mixing 20 parts by weight of cement, 60 parts by weight of rice husk ash and 20 parts by weight of silica and then sintering at 800 ° C. for 12 hours is prepared as a continuous porous molded body. 0.01 g of Aragekawaratake mushrooms were cultured in a liquid PD medium at 28 ° C. for 1 day, and a continuous porous molded body having a particle size of 3 mm was poured and immersed therein, and further cultured at 28 ° C. for 1 day. Thereafter, only the continuous porous molded body was taken out, put into a column, and cultured as it was for 7 days. Next, 1 L of dye solution was circulated at 2 mL / min through the column thus prepared, and the dye solution was collected every 12 hours, and the absorbance was measured to calculate the decolorization rate. As the dyeing solution, a dyeing solution having a concentration of 0.1 mg / L was prepared using three kinds of dyes: a cationic dye (Astrazone blue) and an acid dye (Lanasan blue) and a reactive dye (Cibacron blue), and measured. The results are shown in Table 1.

<Example 2>
The same procedure as in Example 1 was conducted except that 0.005 g of oyster mushrooms and 0.005 g of shiitake mycelia were used instead of the fungus mushrooms in Example 1.

<Example 3>
The same procedure as in Example 1 was performed except that the continuous porous molded body was crushed to a particle size of 5 mm in Example 1.

<Comparative Example 1>
In Example 1, it carried out like Example 1 except having changed the particle size of the continuous porous molded object into 10 mm.

<Comparative example 2>
Example 1 was carried out in the same manner as Example 1 except that 80 parts by weight of cement and 20 parts by weight of silica were used.

<Comparative Example 3>
Example 1 was carried out in the same manner as Example 1 except that 80 parts by weight of cement and 20 parts by weight of rice husk ash were used.

  As can be seen from Table 1, the basidiomycetes produced from the mushrooms of the present invention immobilized on a continuous porous material that was crushed were able to decolorize cations, reactions and acid dyes and were satisfactory. However, in Comparative Example 1 in which the continuous porous molded body was not crushed and in Comparative Example 2 in which the continuous porous molded body did not contain rice husk ash, the decolorization rate was not satisfactory. Further, Comparative Example 3 containing no aggregate was brittle and could not form a continuous porous body.

  The technology of the present invention fixes bacteria having the ability to decolorize a dye to a continuous porous molded body, and passes the dye solution through the continuous porous molded body, thereby bringing the bacteria into contact with the dye solution and decolorizing. Therefore, the fields used are wide and are widely used by selecting the type of bacteria to be fixed.

Claims (6)

A dye decolorizing carrier comprising: immobilizing at least one or more bacteria on a continuous porous molded body, and bringing the dye solution into contact with the bacteria to decolorize the dye. 2. The dye decolorizing carrier according to claim 1, wherein the continuous porous molded body is obtained by crushing a continuous porous molded body containing rice husk ash. The continuous porous molded body is obtained by crushing one or more binders selected from the group consisting of cement and gypsum, and a continuous porous molded body containing rice husk ash and inorganic aggregate. Item 3. The dye decolorizing carrier according to Item 1 or 2. The dye decolorizing carrier according to any one of claims 1 to 3, wherein the continuous porous molded body is obtained by crushing the continuous porous molded body so as to have a particle size of 0.5 mm to 5 mm. The carrier for dye decolorization according to any one of claims 1 to 4, wherein the bacterium is immobilized on a continuous porous molded body at least one or a plurality of basidiomycetes selected from the group of basidiomycetes of Aragekawaratake, Kawaratake, Shiitake, and oyster mushrooms. A method for decolorizing a dye by the dye decolorizing carrier according to any one of claims 1 to 5.