JPS5843348B2 - Method for producing inorganic cured body - Google Patents

Description

[Detailed description of the invention] This invention relates to a method for producing an inorganic cured body.

A lime component raw material and an alumina component raw material are mixed in a predetermined ratio and fired to form a tri-lucium aluminate solid solution (3CaO-
A1203) was added to this and the required amount of water was added to produce a 3-force lucium aluminate 6 hydrate solid solution (3CaO
Calcium aluminate trisulfate hydrate (3CaO-A
1203・3CaSO4・31~32H20, hereinafter TS
The method for producing an inorganic cured body in which TSH is synthesized, shaped into a desired shape, and then cured to produce an inorganic cured TSH body has the problem that the production volume cannot be increased due to the slow reaction rate. was there.

Therefore, an object of the present invention is to provide a method for producing an inorganic cured product that can increase the production amount.

In summary, the present invention provides a trivalent lucium aluminate solid solution (3CaO-A1203, hereinafter abbreviated as C3A) or a trivalent lucium aluminate 6 hydrate solid solution (3C
aO-A1203・6H20, hereinafter abbreviated as C3AH6)
Gypsum and ethanolamine are added and mixed, shaped into a desired shape, and then cured to produce an inorganic hardened product.

The mixing molar ratio of C3A or C3AH6 and gypsum is C3
Gypsum (CaSO4
・2H20, CaSO4 ・1/2H20, Ca5O4)
It is preferable to select it so that it is 2.1 to 3.3 moles.

The amount of ethanolamine added is C3A or C3AH6
It is preferable to select the amount from 1 to 7% based on the slurry mixture obtained by adding gypsum and gypsum water.

In addition to the above raw materials, other additives such as reinforcing materials and fillers may be added.

Next, a method for producing an inorganic cured body will be explained.

The C3A used in this invention may be obtained in any way, but for example, it can be obtained by mixing CaO and Al2O3 at a molar ratio of approximately 3:1 and firing this at a high temperature of 900 to 1400°C. I can do it.

C3AH6 can be obtained by, for example, hydrating C3A in the form of fine powder, or mixing CaO and Al2O3 in a molar ratio of approximately 3:1.
It can be obtained by adding water to and mixing the mixture, which is 0.5 to 6 times the amount of the solid content, and subjecting the mixture to a wet heat reaction in an autoclave.

Ethanolamine is monoethanolamine (HOCH
2CH2NH2), jetanolamine (HOCH2C
H2)2NH, triethanolamine (HOCH2CH
2) s N.

The above raw materials and gypsum are blended in a desired blending ratio.

At this time, adjust the water mixing ratio appropriately. Then, the obtained mixture is shaped and cured to produce an inorganic cured body.

Next, examples will be described.

Example 1 561 parts of CaO that had passed through 200 meshes (same weight basis and below) and 3780 parts of Al(OH) that had passed through 100 meshes were mixed and placed in an electric furnace and heated at 1,100°C for 2 hours to obtain lumpy C3A. .

This lumpy C3A is crushed and the amount passing through 300 meshes is converted into C3.
It was used as raw material A.

Next, asbestos (Canadian chrysotile 6D) 40
1 part is defibrated in a high-speed mixer using 2000 parts of water, and 25 parts of glass fiber (1 part 2-inch chopped strand) is added thereto and further defibrated to prepare a fiber solution.

On the other hand, the aforementioned C3A270.3 parts and dihydrate gypsum 516.
A mixture is made by mixing 3 parts and 1,000 parts water in a high speed mixer.

Transfer these fiber solutions and mixture to a propeller type stirrer,
Add 240 parts of triethanolamine and 5,000 parts of water and mix uniformly.

Next, this is made into paper using a paper making machine, placed in a mold, and pressure-molded using a press to produce a plate-shaped extruded body, which is heated at a temperature of 2.
After curing for 2 days at 5° C. and 100% RH, an inorganic cured product was obtained.

The bending strength of this cured product at each bulk specific gravity is as follows.

Example 2 2741 parts of Ca(OH), 3780 parts of Al(OH), and 3000 parts of water were placed in an autoclave equipped with a stirrer, and the temperature was raised to 190°C in about 45 minutes.
After reacting for 2 hours at
A H6 slurry was obtained.

An inorganic cured body was obtained using the same formulation and operation as in Example 1, except that 378.3 parts of this C3AH6 slurry was used.

The bending strength of the obtained cured product at each bulk specific gravity is as follows.

Comparative Examples 1 and 2: Inorganic cured products were obtained in the same manner as in Examples 1 and 2, except that triethanolamine in Examples 1 and 2 was omitted.

The reaction rates in the above Examples and Comparative Examples were determined by X-ray diffraction and are shown in FIG.

In the figure, A is Example 1. B is Example 2. C is Comparative Example 1. D is the reaction rate curve of Comparative Example 2.

As is clear from the figure, addition of triethanolamine greatly increases the reaction rate.

Next, FIG. 2 shows the degree of improvement in reaction rate depending on the type of ethanolamine.

That is, Figure 2 shows the degree of reaction rate improvement when 3.77 parts of each ethanolamine was added to 27 parts of C3A, 51.6 parts of gypsum, and 47 parts of water, and F is the increase in reaction rate when triethanolamine is used. , G shows the reaction rate curve when jetanolamine is used, H shows the reaction rate curve when monoethanolamine is used, and ■ shows the reaction rate curve when ethanolamine is excluded.

As is clear from the figure, triethanolamine improves the reaction rate the most, followed by jetanolamine and then monoethanolamine.

As described above, the method for producing an inorganic cured body of the present invention comprises three steps.
Gypsum and ethanolamine are added to and mixed with a lucium aluminate solid solution or a 3-lucium aluminate hexahydrate solid solution, shaped into a desired shape, and then cured, resulting in a faster reaction rate.

As a result, the production amount of the inorganic cured product can be increased.

[Brief explanation of the drawing]

FIG. 1 is a reaction rate curve diagram, and FIG. 2 is a reaction rate improvement curve diagram depending on the type of ethanolamine.

Claims (1)

[Claims] A method for producing an inorganic hardened body, which comprises adding gypsum and ethanolamine to a 13-force lucium aluminate solid solution or a 3-force lucium aluminate 6-hydrate solid solution, mixing the mixture, shaping it into a desired shape, and then curing it.