KR101263227B1 - Geopolymer Composition having high strength and manufacturing method thereof - Google Patents

Abstract

The present invention relates to a high-strength geopolymer composition comprising fly ash and amorphous aluminosilicate, wherein the mixture of fly ash: aluminosilicate is 80: 20-20: 80 with modified liquid potassium silicate, which is an alkali stimulant, Adding 50% by weight, the geopolymer composition of the present invention can exhibit a much higher level of initial and later compressive strength than conventional cement. The present invention also proposes a geopolymer composition which can express strength of 100 MPa (3 days) and 130 MPa (28 days) or more using fly ash and amorphous aluminosilicate, respectively.

Description

High strength geopolymer composition and method for manufacturing same

The present invention relates to a high strength geopolymer composition comprising fly ash and amorphous aluminosilicates and a method of making the same.

Recently, technologies for using fly ash as a cement substitute have been developed. Fly ash is currently generated from thermal power plants and cogeneration plants. These fly ash materials are expected to be excellent raw materials for filling with high ratio of amorphous glass phase, clay-like chemical composition and spherical particle characteristics. to be. The present invention is to provide a geopolymer composition of ultra high strength (100Mpa) by the addition of highly active blast furnace slag and metakaolin to such a fly ash.

Unlike the conventional cement manufacturing process, this geopolymer composition manufacturing process has a low energy consumption and does not emit a large amount of CO ₂ . In addition, there is an advantage that does not require mechanical mixing (milling), elution for a long time, high temperature reaction (more than 100 ℃) to give a special high energy. The geopolymer composition prepared by the present invention exhibits very stable volume stability, high initial and late compressive strength, excellent durability and high fire resistance.

Geopolymer composition according to the present invention is a geopolymer mortar, concrete and heavy metals for fireproof panels, fireproof panels, high-strength concrete, high-strength repair mortar, artificial marble, artificial rock, building materials, ceramic tiles, buildings, etc. It can be utilized as a useful binder for immobilization of various industrial by-products.

Geopolymer manufacturing techniques known to date have used silicates and hydroxides as alkaline materials such as pure alumina, silica, calcium oxide and the like. Korean Patent No. 10-0846821 describes a process for preparing a geopolymer material from fly ash, which is a step of grinding and milling raw fly ash material in a ball mill or vertical roller mill, which is mechanically processed. Mixing in a mixer, mixing with an alkaline activator such as silicate or hydroxide of potassium or sodium, and molding into a desired form and curing at a temperature in the range of 60 to 250 ° C. However, this technique requires energy consumption for processing compared to using the generated fly ash as it is, and since it is manufactured in a temperature range of 60 to 250 ° C. after molding, it also has a disadvantage of consuming a lot of energy.

Korean Patent No. 10-0852215 relates to an eco-friendly ecobrick manufacturing method using a geopolymer reaction of briquette materials. More specifically, eco-friendly ecobrick production using sodium hydroxide aqueous solution as an alkaline stimulant to briquettes produced after briquette combustion. However, this technique uses high concentrations of NaOH, so whitening occurs due to remaining Na ions after the reaction, and whitening generated on the surface becomes a major factor that causes product contamination. In addition, since high concentration of NaOH is used, the alkalinity of the product is high, so when it is installed near a river or a human body, it may cause skin trouble by alkali, and thus there is a limit to use.

Korean Patent No. 10-0807244 discloses an amorphous composition of a high refractory inorganic binder which improves the structural safety and heat shielding properties of main structural members by preventing cross-sectional loss and explosive explosion caused by high temperature due to fire in high-rise and underground concrete structures. The present invention relates to an orthopedic fireproof board manufactured from the composition, wherein the fly ash 5-20 wt%, the metakaolin 5-20 wt%, the fine aggregate 35-70 wt%, the alkaline stimulant 5-15 wt% and the alkali silicate solution 5-10 wt% Korean Patent No. 10-0759855 relates to a non-plastic inorganic binder using an alkali stimulant and fly ash, and replaces cement and cement secondary products by recycling a large amount of fly ash generated and discarded in Korea. To provide non-plastic inorganic binders, but these patents use fly ash and metakaolin, In age 28 days the compressive strength has a drawback stopping to about 20MPa since the property is not a composition which can sufficiently exhibit the compressive strength of the composition. This low compressive strength makes it possible to use the structure as an auxiliary but difficult to use as a structure.

Korean Patent No. 10-0796534 discloses a binder composed of 30 to 60% by weight of Portland cement, 30 to 60% by weight of blast furnace slag powder, and 10 to 30% by weight of fly ash as a binder of the concrete composition. This technology also uses blast furnace slag or fly ash as a substitute for cement, so it is not an efficient way to recycle waste resources. As a result, there is a problem that whitening occurs.

In addition, the above techniques also have problems of lack of compressive strength and fluidity. Cement-containing compositions solve the problem by adding a separate water reducing agent, a fluidizing agent, etc. due to the lack of fluidity.

The present invention aims to solve the problems of the prior arts, and in particular, to provide a substitute material for cement. Another object of the present invention is to provide a geopolymer composition having excellent initial and later compressive strengths (100 MPa or more). Still another object of the present invention is to extend the amount of fly ash to 80% by weight. It is yet another object of the present invention to provide a wider range of construction materials and applications requiring varying strengths by providing high strength geopolymer compositions.

The geopolymer composition of the present invention is a fly ash: amorphous aluminosilicate weight ratio of 80: 20 ~ 20: 80 to 1 to 5% by weight of the reaction regulator is added to the mixed powder 100 parts by weight of potassium silicate 30 ~ It consists of adding 30-50 parts by weight of a modified liquid potassium silicate consisting of 80% by weight, caustic carry 5-30% by weight and water 15-60% by weight. Table 1 shows the chemical composition of the powder.

[Table 1]

The fly ash used in the present invention includes not only the bituminous coal fly ash of the thermal power plant used in the above inventions, but also anthracite fly ash containing a large amount of fly ash and coal briquettes generated from cogeneration plants with little utility.

Anthracite fly ash or cogeneration fly ash, which could not be utilized in the existing cement production, is also a very important raw material in the present invention. Regardless of the type of fly ash, when the amount used is 90% by weight or more, it is difficult to express the compressive strength of 100 MPa intended in the present invention because of low reactivity of the fly ash, and shows a low compressive strength of 53 MPa or less even after 28 days of curing.

In addition, when the addition amount of the fly ash is less than 20% by weight, the compressive strength shows an extremely high strength of 140 MPa or more, but it becomes a problem that the long-term strength due to the occurrence of cracks on the surface is lowered. Due to its heterogeneity, it is not suitable for structural use in buildings.

The role of the fly ash used also plays a very important role in the geopolymer composition. Fly ash is a spherical particle having a particle size of about 20 μm, which facilitates the flow between particles and absorbs a small amount of the added liquid. Therefore, the fly ash can be molded even with a small amount of alkaline solution, which is economically economical.

Amorphous aluminosilicates usable in the present invention may be blast furnace slag, metakaolin, silica fume, etc., in which a large amount of the amorphous glass phase is contained, and more particularly, the filling properties of the geopolymer composition using a mixture of blast furnace slag and metakaolin. It was adapted for improvement and high intensity expression.

In the case of the use amount of 20% by weight or less, the strength is low because it must be dependent on the reactivity of the fly ash, and in the case of 80% by weight or more, the use of blast furnace slag increases, so that the initial quenching and hydration heat generated therefrom occurs. As a result, there is a concern that cracks are generated, and since cracks are caused by expansion and growth of cracks, long-term strength is lowered. In addition, since the amount of fly ash is lowered, it is difficult to secure fluidity, recyclability is low, and the amount of modified liquid potassium silicate is also greatly increased, resulting in an increase in production price.

In the present invention, the blast furnace slag and metakaolin are adjusted in the range of 3.5 to 4.70 molar ratio of SiO ₂ / Al ₂ O ₃ in consideration of the reactivity with fly ash. Most preferably, the mass ratio of SiO ₂ / Al ₂ O ₃ is about 4.16.

The blast furnace slag has a brain characteristic of 6,000 cm 3 / g, and is preferably used. In order to express high strength of 100 MPa, it is preferable to use highly reactive high brain. If higher than this, there is a problem of low economic efficiency, if lower than this, there is a problem of low reactivity.

The addition of metakaolin to blast furnace slag is due to the rapid and long-term drying of the initial hydroxyl groups by the metakaolin clay, which is released again and continuously induces the geopolymer reaction of blast furnace slag and fly ash. In addition, the initial curing speed is also delayed because it rapidly absorbs the hydroxyl group. In addition, it has lower activity (lower calcination temperature) than fly ash or blast furnace slag, but since it contains a large amount of amorphous inside, it is also used as a main raw material for geopolymers. . If the brain is too high, it will interfere with the geopolymer reaction, it is easy to crack due to the particulate properties, and if it is lower than 6,000 cm 3 / g, the reactivity is poor, so it is difficult to express the desired properties in the present invention. It is also preferable to use a blast furnace slag-like brain for homogeneous mixing.

The reaction modifier used in the present invention is to inhibit and promote the initial reaction of CaO of the modified liquid potassium silicate and amorphous aluminosilicate, and organic or inorganic acids such as tartaric acid, citric acid, malonic acid, gypsum, gluconic acid and glucoheptonic acid. Inorganic salts such as NaCl and MgCl ₂ and sewage sludge incinerators, industrial phosphate wastewater, aluminum phosphate wastewater, and various kinds of ginseng salts.

Detailed description of such reaction regulators, tartaric acid, citric acid, malonic acid, gypsum, gluconic acid, etc. in the initial reaction of cement or geopolymer cement, generally serves to lower the alkali of the paste, mainly tartaric acid It is used a lot. Citric acid and malonic acid are often used as a reaction retardant of geopolymers, which are highly alkaline and have a mechanism similar to cement.

Phosphate is used as a retarder for alkaline activated cement as it induces the binding of Ca ions and P ions in cement to inhibit CSH gel formation by the reaction of Ca ions and silica. On the other hand, sewage sludge incineration or aluminum phosphate wastewater is a material that has not been used at present, and aluminum phosphate wastewater is not suitable for the present invention. It exists in solution, and there is a problem that the operation is difficult because it involves a precipitation reaction upon contact with the modified liquid potassium silicate. Sewage sludge incineration, on the other hand, contains more than 15% P ₂ O ₅ and has very good filling. It is preferable to use a mixture of such sewage sludge incinerator and NaCl as a reaction regulator. It can be uniformly mixed by dry mixing with powdered fly ash and amorphous aluminosilicate mixture. Sewage sludge incineration ash is a fly ash incinerated by heat treatment of sewage sludge above 800 ℃.

The reaction modifier has an effect of extending the gel time and the hydration time of the geopolymer by at least 15% of P ₂ O ₅ and NaCl present in the sewage sludge incinerator when the geopolymer powder is in contact with the liquid potassium silicate. Especially when P ₂ O ₅ in sewage sludge ash is mixed with Ca ions contained in amorphous aluminosilicate powder with modified liquid potassium silicate in solution, two P ions bind to 5 Ca ions. It forms an intermediate of the initial calcium phosphate, and consumes Ca ions to inhibit the contact between Si (OH) ₄ and Ca ions.

NaCl also serves to lower the heat of hydration and polycondensation of geopolymers. In this way, the formation of calcium silicate gel according to the reaction of Ca ions and Si ions, which are the initial reactions of the geopolymers, is suppressed and the surface hardening is suppressed. It is possible to obtain a stable geopolymer molded body by securing the movement time to the surface (remaining fluidity such that no crack occurs on the surface of the molded body when water moves to the surface).

As a reaction regulator, it is preferable to use a powder mixed with sewage sludge incinerator and NaCl in a weight ratio of 8.0 to 9.0: 1.0 to 2.0. When the amount of the reaction regulator is exceeded, it is difficult to express the high strength of 100 MPa desired in the present invention.

In addition, the modified liquid potassium silicate according to the present invention is composed of 30 to 80% by weight potassium silicate, 5 to 30% by weight caustic and 15 to 60% by weight of water. Potassium silicate is used in the range of 30 to 80% by weight, most preferably 50% by weight. Also caustic is preferably 5 to 30% by weight, most preferably 10% by weight. Caustic carry's role is to promote alkali irritant effect through pH increase. The amount of caustic and potassium silicate added is determined according to the amount of water used, and the amount of water is preferably 15 to 60% by weight. Most preferably 30% by weight is added.

It is necessary not to use existing alkaline materials with any Na ₂ O. The use of Na ₂ O in high dissociation properties is not desirable because the object of the present invention is to be exposed to nature to contact with rain or to be used in the air temperature change and in water. In addition, Na ₂ O, which is highly dissociable, is included in the condensation or evaporation process of moisture and is transferred to the surface and reacts with CO ₂ gas in the air to generate substances such as Na ₂ CO ₃ , causing whitening. Since cracks on the surface occur, there is a problem of inferior long-term stability. For this purpose, it is necessary to design low dissociation of Na ₂ O or to use materials having excellent water repellency or waterproofing properties, thereby decreasing general utility. Potassium silicate used in the present invention and caustic used in the reforming is one of the main raw materials mainly used where whitening is concerned because the rate of curing at room temperature is low and the carbonic acid reaction is lower than that of sodium silicate.

The modified liquid potassium silicate composition used in the present invention is in the range of 30 to 80% by weight potassium silicate, 5 to 30% by weight caustic and 15 to 60% by weight of water, respectively, the amount of each of which is out of this limited range, In case of potassium, when used at 30% by weight or less, the amount of monomer production of Si (OH) ₄ , which acts as a seed in geopolymer formation, is insufficient, so that initial and long-term strength cannot be satisfied, and exceeds 80% by weight. In this case, the concentration is very high, and the fluidity is greatly reduced. In order to secure the minimum flowability of 180mm to 230mm for filling the mold, it is necessary to add an excessive amount to secure the target flowability.

At the same time, problems such as whitening occur due to the generation of free SiO ₂ due to the formation of excess monomers. In addition, if a modified liquid suitable for economical efficiency is added, a relatively small amount should be used, so that molding is difficult due to lack of fluidity, which causes a quenching, which makes the molding operation itself difficult. In addition, when caustic carri is added below 5% by weight, the pH value cannot achieve the target 12.5, and when 30% by weight is used, the pH value becomes> 14, which increases the alkali irritant effect but causes excessive Alkaline cations and OH radicals can cause problems that adversely affect the environment. In addition, there is a problem that the weight ratio rises sharply, and the economic feasibility decreases.

In addition, when the amount of water used is less than 15% by weight, the specific gravity is increased, so that a large amount of modified liquid potassium silicate must be added in order to secure effective fluidity, and the market competitiveness due to the price increase is lowered. In addition, if it exceeds 60% by weight, it is advantageous in securing fluidity and economical efficiency, but it is difficult to manufacture a high strength binder targeted in the present invention, and in particular, the amount of the combustion material suitable for expressing the compressive strength required as a building material is There is a problem of being very low.

In addition, the modified liquid potassium silicate used in the present invention is preferably used so that the ratio (molar ratio) of K ₂ O / SiO ₂ to industrial potassium silicate is 0.63 to 1.0 so as to have a pH of 12.5 or more. When the K ₂ O / SiO ₂ ratio of potassium silicate used is less than the above-mentioned range, the initial compressive strength is hardly expressed, and when it exceeds the above-mentioned range, it breaks down even at a small impact due to lack of fluidity and crack generation due to high specific gravity. Problems may arise. More preferably, the ratio of K ₂ O / SiO ₂ is adjusted to be used in the range of 0.60 to 0.80.

If the ratio of K ₂ O / SiO ₂ exceeds 0.80, the pH value will increase to 12 or more when the final product (28 days) is in contact with water bodies. It becomes difficult to use. When used within this range, the pH value at the 28-day water contact of the final product may be 12 or less, contributing to the formation of a stable ecological habitat in terms of water environment.

In addition, the amount of the modified liquid potassium silicate is preferably used in an amount of 30 to 50 parts by weight based on 100 parts by weight of a mixture of fly ash, amorphous aluminosilicate, and a reaction regulator. If this range is exceeded, it is difficult to secure the target fluidity and compressive strength, and the business feasibility is lowered due to the lack of economy due to liquidity and use.

Method for producing a geopolymer composition of the present invention comprises the steps of fly ash: amorphous aluminosilicate ratio of 80: 20 ~ 20: 80 mixing; 1-5% by weight of the reaction regulator was added for 5 minutes high speed mixer; It consists of adding 30-50 weight part of modified liquid potassium silicate consisting of 30-80 weight% of potassium silicates, 5-30 weight% of caustic carry, and 15-60 weight% of water with respect to 100 weight part of mixed powders. The composition thus obtained is an ultrahigh strength geopolymer composition which exhibits a compressive strength of 100 MPa or more at 3 days of age and 130 MPa or more at 28 days of age only by performing low temperature curing for 4 to 24 hours in a temperature range of room temperature to 100 ° C.

The high-strength geopolymer composition of the present invention exhibits very high initial and late compressive strengths without the use of cement, and can sufficiently secure crack generation and fluidity which adversely affects the strength development. The geopolymer composition may be used together with sand, aggregate, and the like, and may be effectively used as road paving materials, building materials, repair materials, and the like. In addition, it can be mixed with ceramic fiber and ceramic chamotte, etc., and used as a heat insulation material for fireproof, fireproof panel, and concrete anti-expanding coating.

1 is an electron micrograph of the specimen obtained in Examples 1, 3, 5, 7,
2 is a graph showing the results of XRD diffraction analysis of the specimen obtained in Examples 1, 3, 5, 7,
3 is a chemical composition analysis photograph in the microstructure of the specimen obtained by Example 5 and Comparative Example 3,
4 is an external photograph of specimens obtained by Example 5 and Comparative Example 3;
5 is an electron micrograph of a specimen obtained in Comparative Example 5,
6 is an electron micrograph of a specimen obtained in Comparative Example 6.

An embodiment of the present invention is as follows.

( Example  One)

Fly ash: Amorphous aluminosilicate: Mixing ratio of reaction modifier (sewage sludge incinerator: NaCl = 8.5: 1.5, weight ratio) of 77: 20: 3 mixture to 100 parts by weight of K ₂ O / SiO ₂ ratio of 0.65 33 parts by weight of the modified liquid potassium silicate having a content of 45% of the solid content adjusted by using the slurry was prepared to be in the range of 180 to 230 mm, and then, bubbles were removed while applying vibration to a 5 × 5 × 5 cm triple cube mold. Molded in a method of filling, which is then maintained at room temperature for 4 hours to balance the surface and internal evaporation of water, and then cured for 8 hours at a temperature of 60 ° C., measured for 3, 7, and 28 days. The compressive strengths of the specimens were 101.7MPa, 115.0MPa and 135.7MPa, respectively. The compressive strengths of the specimens were 10.87 MPa.

Electron micrographs of the fracture surfaces of the specimens prepared in Examples 1, 3, 5, and 7 were as shown in FIG. 1. The microstructure of the geopolymer composition prepared by the present example is very dense, the particles are expected to be fly ash and the glassy phase therein, and were more dense in the specimen with the lower amount of fly ash added. In addition, XRD diffraction analysis results were as shown in FIG.

As shown in Figure 2 it can be confirmed the peak characteristics of the round hill-shaped peak of 20 ° ~ 35 ° (2θ) symbolizes the geopolymer, the higher the content of the fly ash, the larger the range and area was shown.

The chemical component analysis results in the microstructure were as shown in FIG. 3. From the chemical component analysis results of the dense part of the geopolymer composition, it was confirmed that the peaks of Si, Al, and Ca, which are major components of fly ash and amorphous aluminosilicate, were strongly developed. In addition, the peaks of K ions were also expressed from the use of the modified liquid potassium silicate (Table 2).

[Table 2]

( Example  2)

The same procedure as in Example 1 was carried out, but the mixing ratio of fly ash: amorphous aluminosilicate was changed to 67:30. As a result, the compressive strengths of 3, 7, and 28-day-old specimens were 112.9 MPa, 136.3 MPa, and 145.9 MPa, respectively.

( Example  3)

The same procedure as in Example 1 was carried out, but the mixing ratio of fly ash: amorphous aluminosilicate was changed to 57:40, and the modified liquid potassium silicate was changed to 36 parts by weight.

As a result, the compressive strengths of 3, 7, and 28-day-old specimens were 135.9 MPa, 137.7 MPa, and 149.7 MPa, respectively. The pH value of the specimens completed at 28 days of age was 10.89.

( Example  4)

The same procedure as in Example 1 was carried out, but the mixing ratio of fly ash: amorphous aluminosilicate was changed to 50:47. As a result, the compressive strengths of 3, 7, and 28 days old specimens were 145.7 MPa, 157.2 MPa, and 159.3 MPa, respectively.

( Example  5)

The same procedure as in Example 1 was carried out, but the mixing ratio of fly ash: amorphous aluminosilicate was changed to 40:57, and the modified liquid potassium silicate was changed to 38 parts by weight. As a result, the compressive strengths of 3, 7, and 28-day-old specimens expressed 156.6 MPa, 173.5 MPa, and 178.0 MPa, respectively. The pH value of the specimens completed at 28 days of age was 11.59. The appearance photograph of the specimen showing the highest strength value among the geopolymer compositions invented by the present invention is shown in FIG. 4 (FIG. 3 left).

( Example  6)

In the same manner as in Example 1, the mixing ratio of fly ash: amorphous aluminosilicate was changed to 30: 67, and the modified liquid potassium silicate was changed to 39 parts by weight. As a result, the compressive strengths of 3, 7, and 28-day-old specimens expressed 160.9 MPa, 159.0 MPa, and 177.0 MPa, respectively.

( Example  7)

In the same manner as in Example 1, the mixing ratio of fly ash: amorphous aluminosilicate was changed to 20: 77, and the modified liquid potassium silicate was changed to 40 parts by weight. As a result, the compressive strengths of 3, 7, and 28-day-old specimens expressed 160.9 MPa, 159.0 MPa, and 177.0 MPa, respectively. The pH value of the specimens completed at 28 days of age was 11.50.

( Comparative example  One)

The same procedure as in Example 1 was carried out, but the mixing ratio of fly ash: amorphous aluminosilicate was changed to 97: 0, and the modified liquid potassium silicate was changed to 30 parts by weight. As a result, the compressive strengths of 3, 7, and 28 days old specimens showed 18.2 MPa, 23.1 MPa, and 27.4 MPa, respectively. The pH value of the specimens completed at 28 days of age was 10.50.

( Comparative example  2)

The same procedure as in Example 1 was carried out, but the mixing ratio of fly ash: amorphous aluminosilicate was changed to 87:10, and the modified liquid potassium silicate was changed to 32 parts by weight. As a result, the compressive strengths of 3, 7, and 28 days old specimens expressed 33.8 MPa, 48.7 MPa, and 53.5 MPa, respectively.

( Comparative example  3)

In the same manner as in Example 1, the mixing ratio of fly ash: amorphous aluminosilicate was changed to 10: 87, and the modified liquid potassium silicate was changed to 44 parts by weight. As a result, the compressive strengths of 3, 7, and 28-day-old specimens expressed 145.7 MPa, 126.4 MPa, and 109.3 MPa, respectively. The pH value of the specimens completed at 28 days of age was 11.63.

The decrease in long-term strength means that the role of the fly ash is to maintain the long-term strength, and at the same time, the rapid reaction due to the high content of blast furnace slag and metakaolin causes cracks due to the movement of water to the surface and the heat of hydration, and it grows and cracks. This is due to the occurrence. Figure 4 shows a photograph of the specimen produced as a comparative example (Fig. 3 right).

( Comparative example  4)

The same procedure as in Example 1 was carried out, but the mixing ratio of fly ash: amorphous aluminosilicate was changed to 5:92, and the modified liquid potassium silicate was changed to 44 parts by weight. As a result, the compressive strengths of 3, 7, and 28-day-old specimens expressed 149.7 MPa, 161.5 MPa, and 109.0 MPa, respectively.

( Comparative example  5)

Usually, 30 parts by weight of water is added to 100 parts by weight of Portland cement, followed by slurrying, followed by vibration filling molding in a vibration molding machine. The molded specimens were naturally cured for 4 hours and then demolded and cured at 60 ° C. for 8 hours. After curing, the specimens were cured for 3, 7, 28 days, and the compressive strength characteristics were evaluated. As a result, the compressive strengths of 3, 7, and 28 days old specimens were 48.1 MPa, 57.4 MPa, and 60.6 MPa, respectively, which are very low values compared to the compressive strength of the geopolymer composition. In addition, the pH value after 28 days of water contact of the 28-day age specimen was 13.3. Figure 5 shows a microstructure photograph after 28 days of age of cement. In the picture, the needle-shaped particles, which are expected to be cement hydrates, are well developed between the plate-shaped particles. This can be confirmed that very different from the microstructure of the geopolymer composition of FIG.

[Table 3]

[Table 4]

( Example  8)

Embodiment, but the same procedure of 4, and changes the mole ratio of the modified K ₂ O / SiO ₂ of liquid potassium silicate as 0.60. Invention conditions and strength measurement results are shown in Tables 3 and 4. As a result, after 3, 7, 28 days of age the compressive strength was 136.2MPa, 145.7MPa, 156.2MPa respectively.

( Example  9)

Embodiment, but the same procedure of 4 was modified to change the molar ratio of K ₂ O / SiO ₂ of liquid potassium silicate 0.70, 40 parts by weight. As a result, the compressive strengths of 136.9 MPa, 133.5 MPa, and 158.7 MPa were exhibited after 3, 7, and 28 days of age, respectively.

( Example  10)

Embodiment, but the same procedure of 4, and changes the mole ratio of the modified K ₂ O / SiO ₂ of liquid potassium silicate 0.75 and 43 parts by weight. As a result, after 3, 7, 28 days of age, the compressive strength was 132.6MPa, 133.1MPa, 156.1MPa, respectively.

( Example  11)

Embodiment, but the same procedure of 4, and changes the mole ratio of the modified K ₂ O / SiO ₂ of liquid potassium silicate 0.80, 45 parts by weight. As a result, after 3, 7, 28 days of age, the compressive strength was 129.3MPa, 150.3MPa, 157.2MPa, respectively.

( Example  12)

Embodiment, but the same procedure of 4, and changes the mole ratio of the modified K ₂ O / SiO ₂ of liquid potassium silicate 0.90, 47 parts by weight. As a result, after 3, 7, 28 days of age, the compressive strength was 137.5MPa, 149.5MPa, 172.6MPa, respectively.

( Example  13)

Embodiment, but the same procedure of 4, and changes the mole ratio of the modified K ₂ O / SiO ₂ of liquid potassium silicate 1.00, 50 parts by weight. As a result, after 3, 7, 28 days of age, the compressive strength was 146.6MPa, 143.2MPa, 177.5MPa, respectively.

( Comparative example  6)

Embodiment, but the same procedure of 4 was modified to change the molar ratio of K ₂ O / SiO ₂ of liquid potassium silicate 0.48, 40 parts by weight. As a result, after 3, 7, 28 days of age the compressive strength was 4.1MPa, 7.1MPa, 18.5MPa respectively. 6 shows a microstructure photograph of a 28-day-old specimen of the prepared specimen. As can be seen from the electron micrographs, there are many individual particles that do not participate in the reaction, and there are large cracks across the center of the microstructure.

( Comparative example  7)

Embodiment, but the same procedure of 4 was modified to change the molar ratio of K ₂ O / SiO ₂ of liquid potassium silicate 0.56, 40 parts by weight. As a result, the compressive strengths of 6.6 MPa, 9.6 MPa, and 19.0 MPa were achieved after 3, 7, and 28 days of age, respectively.

[Table 5]

TABLE 6

[Table 7]

[Table 8]

( Example  14)

Embodiment, but the same procedure of 4, modified to secure the molar ratio of K ₂ O / SiO ₂ of liquid potassium silicate to 0.65, and by changing the addition amount to 20% by weight of water in the liquid phase reforming was added 37 parts by weight. As a result, after 3, 7, 28 days of age, the compressive strength was 133.8MPa, 146.1MPa, 164.8MPa, respectively.

( Example  15)

Embodiment, but the same procedure of 4, modified to secure the molar ratio of K ₂ O / SiO ₂ of liquid potassium silicate as 0.65, and the amount of water in the liquid was added 35 parts by weight modified by changing to 30% parts by weight. As a result, after 3, 7, 28 days of age the compressive strength was 143.8MPa, 137.7MPa, 166.7MPa respectively.

( Example  16)

Embodiment, but the same procedure of 4, modified to secure the molar ratio of K ₂ O / SiO ₂ of liquid potassium silicate as 0.65, and the amount of water in the liquid phase reforming was added to change to 55% parts by weight of 37 wt. As a result, after 3, 7, 28 days of age, the compressive strength was 118.3MPa, 120.5MPa, 129.6MPa respectively.

( Comparative example  8)

The same procedure as in Example 16 was carried out, except that 37 parts by weight of water was changed to 70% by weight. As a result, the compressive strength of 76.9 MPa, 87.4 MPa, and 89.3 MPa after 3, 7, 28 days of age, respectively.

Claims (5)

Fly ash: mixing so that the weight ratio of amorphous aluminosilicate is 80: 20-20: 80; Adding 1 to 5% by weight of a powdery reaction control agent mixed with sewage sludge incinerator and NaCl in a weight ratio of 8.0 to 9.0: 1.0 to 2.0; 30 to 80 parts by weight of modified liquid potassium silicate consisting of 30 to 80% by weight of potassium silicate, 5 to 30% by weight of caustic carry, and 15 to 60% by weight of water to 100 parts by weight of the mixed powder to which the reaction regulator is added. Method for preparing ultra high strength geopolymer composition.
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