CN111232997A - Method for co-producing analcime by high-modulus water glass and product thereof - Google Patents

Abstract

The invention relates to the field of utilization of silicon and aluminum mineral residues, and discloses a method for co-producing analcite with high modulus water glass. Mixing to carry out hydrothermal reaction, then carrying out solid-liquid separation to obtain high modulus water glass solution and filter residue; _II ) washing and drying the filter residue to obtain analcite; wherein, the content of SiO in the silicon residue is 50-80% by weight, and the content of Al ₂ O ₃ is 10-20% by weight. The water glass prepared by this method has a high modulus, and the Na ₂ O content in the water glass can meet the requirements of industrial liquid sodium silicate. At the same time, analcite is prepared, which realizes the full utilization of silicon slag and improves the utilization of resources as a whole. Rate.

Description

Method for co-producing analcite with high modulus water glass and product thereof

technical field

The invention relates to the field of utilization of silicon and aluminum mineral residues, in particular to a method for co-producing analcite with high-modulus water glass, a method for preparing high-modulus water glass co-producing analcite from silicon slag or high-alumina fly ash, and products thereof .

Background technique

The solid residues of fly ash, coal gangue and kaolin that are mainly stockpiled after aluminum extraction have caused serious pollution to the surrounding environment and buried greater safety hazards, but these solid residues are still rich in silicon and aluminum components. , usually the content of SiO ₂ in the residue is about 50-80%, and the content of Al ₂ O ₃ is about 5-20%. The resource utilization of these solid residues can not only solve the environmental harm caused by them, but also improve the Economic and social benefits of comprehensive utilization of fly ash, coal gangue and kaolin.

Water glass is an aqueous solution of sodium silicate, which is a widely used chemical product. The production methods of water glass are divided into solid phase method and liquid phase method; solid phase method is to mix quartz sand and soda ash in a certain proportion and then melt at high temperature to generate molten solid sodium silicate. High modulus water glass, but high energy consumption. The liquid phase method for producing water glass is to react sodium hydroxide solution and quartz powder in a reactor to generate sodium silicate solution, and then filter to obtain water glass product, which has low energy consumption. , but the modulus of water glass is lower.

Zeolite is a kind of aluminosilicate with developed pore structure. It has very good ion exchange performance, adsorption performance and catalytic performance. It is widely used in water treatment, gas drying and other chemical fields. Analcite is an aluminum-containing sodium aluminosilicate with a structural formula of [Na(Si ₂ Al) 0 ₆ ·H ₂ O]. Most analcites have a fixed chemical composition, with only a small amount of potassium or calcium substituted for sodium, and some aluminum substituted for silicon. Analcite has huge potential market value in metal ion adsorption and screening separation, gas separation, and pure water separation. After chemical modification treatment, analcite shows unique molecular sieve characteristics, and has a good adsorption effect on heavy metal ions such as Pb, Cu, Zn, etc., and can be used to treat wastewater containing such heavy metals.

In the preparation process of traditional analcite molecular sieves, medicines and reagents with higher chemical purity are basically used, and low-purity raw materials with low price are rarely used. The output of high-alumina fly ash in China is huge, and its main components are SiO ₂ and Al ₂ O ₃ . After the high-alumina fly ash is extracted from aluminum by acid method, silicon slag is produced. In engineering, silicon slag is often used as a pad foundation. The consumption of slag is still low compared to the huge amount of emissions, and a large amount of silicon slag can only be piled up idle, which not only occupies valuable land resources, but may also pollute the environment. The SiO ₂ and Al ₂ O ₃ still contained in the silicon slag can be used as raw materials for the production of water glass and analcite. At present, most of the common fly ash is used to produce water glass or analcite. The produced water glass has a low modulus, and the production of high modulus water glass mostly requires a calcination process, which is complicated and consumes high energy.

SUMMARY OF THE INVENTION

The purpose of the present invention is to overcome the problems in the prior art that the use of fly ash to produce water glass is complicated, the energy consumption is high, and the modulus of the water glass produced is low, and a co-production method for preparing high modulus water glass by using silicon slag is provided. The method of zeolite and the high modulus water glass and analcite products prepared by the method. The method has the advantages of simple operation process, low energy consumption, high modulus of the prepared water glass, the Na ₂ O content in the water glass can meet the standard of industrial liquid water glass ("GB/T4209-2008 Industrial Sodium Silicate"), and at the same time The analite is prepared, the silicon slag residue is fully utilized, and the resource utilization rate is improved as a whole.

In order to achieve the above purpose, a first aspect of the present invention provides a method for co-producing analcite with high modulus water glass, characterized in that the method comprises the following steps:

1) mixing low modulus water glass solution with silicon slag and carrying out hydrothermal reaction, then carrying out solid-liquid separation to obtain high modulus water glass solution and filter residue;

II) washing and drying the filter residue to obtain analcite;

Wherein, the content of SiO ₂ in the silicon slag is 50-80 wt %, and the content of Al ₂ O ₃ is 5-20 wt %.

Preferably, in step I), the hydrothermal reaction temperature is 120-200° C., the hydrothermal reaction time is 1-6 h, and the hydrothermal reaction pressure is 0.2-2.0 MPa.

Preferably, the content of SiO ₂ in the silicon slag is 70-80 wt %, and the content of Al ₂ O ₃ is 8-15 wt %.

Preferably, the silicon slag is selected from at least one of fly ash, coal gangue and silicon slag obtained from aluminum extraction from kaolinite.

Preferably, the silicon slag contains amorphous SiO ₂ .

Preferably, in step 1), the mass ratio of the low modulus water glass to the silicon slag is 1:(2.5-5.0).

The second aspect of the present invention provides a method for preparing high modulus water glass co-producing analcite from silicon slag, characterized in that the method comprises the following steps:

1) mixing silicon slag with sodium hydroxide solution to obtain mixed slurry;

2) carrying out the desiliconization reaction of the slurry, and then carrying out solid-liquid separation to obtain a low modulus water glass solution and a first filter residue;

3) using the low-modulus water glass solution according to the method for co-producing analcite with high-modulus water glass according to the present invention to obtain a high-modulus water glass solution and analcite;

Wherein, the content of SiO ₂ in the silicon slag is 50-80 wt %, and the content of Al ₂ O ₃ is 5-20 wt %.

Preferably, in step 1), the mass ratio of the silicon slag to the sodium hydroxide solution is 1:(3-6), and the mass concentration of the sodium hydroxide solution is 10%-20%.

Preferably, in step 2), the desiliconization reaction temperature is 60-120°C, and the desiliconization reaction time is 0.5-2h;

A third aspect of the present invention provides a method for preparing high-modulus water glass co-producing analcite from high-alumina fly ash, characterized in that the method comprises the following steps:

a) contacting high-alumina fly ash with an acid solution to extract aluminum by acid method to obtain alumina and silicon slag;

b) Using the silicon slag to prepare high-modulus water glass and co-producing analcite by using the method for preparing high-modulus water glass and co-producing analcite described in the present invention.

The fourth aspect of the present invention provides high modulus water glass and analcite prepared by the method of the present invention.

Through the above technical solutions, the present invention realizes the preparation of high-modulus water glass from silicon slag to co-produce analcite, and realizes the full utilization of silicon slag, and the utilization rate reaches 100%, and also provides a high-modulus water glass joint. The simple process for producing analcite, the modulus of the prepared high modulus water glass reaches 3.5, the Na ₂ O content in the water glass can meet the standard of industrial liquid water glass, and the particle size of the prepared anallite is 4-10 μm, Particle size requirements for various analite applications can be met.

Other features and advantages of the present invention will be described in detail in the detailed description section that follows.

Description of drawings

Fig. 1 is the schematic flow sheet of silicon slag system high modulus water glass co-production analcite of the present invention;

Fig. 2 is the XRD spectrum of the analcite prepared in Example 6 of the present invention;

FIG. 3 is an SEM image of the analcite prepared in Example 6 of the present invention.

Detailed ways

Specific embodiments of the present invention will be described in detail below. It should be understood that the specific embodiments described herein are only used to illustrate and understand the present invention, but not to limit the present invention.

The endpoints of ranges and any values disclosed herein are not limited to the precise ranges or values, which are to be understood to encompass values proximate to those ranges or values. For ranges of values, the endpoints of each range, the endpoints of each range and the individual point values, and the individual point values can be combined with each other to yield one or more new ranges of values that Ranges should be considered as specifically disclosed herein.

A first aspect of the present invention provides a method for co-producing analcite with high modulus water glass, characterized in that the method comprises the following steps:

1) mixing low modulus water glass solution with silicon slag and carrying out hydrothermal reaction, then carrying out solid-liquid separation to obtain high modulus water glass solution and filter residue;

II) washing and drying the filter residue to obtain analcite;

Wherein, the content of SiO ₂ in the silicon slag is 50-80 wt %, and the content of Al ₂ O ₃ is 5-20 wt %.

Preferably, the content of SiO ₂ in the silicon slag is 70-80 wt %, and the content of Al ₂ O ₃ is 8-15 wt %.

Preferably, the residue satisfying the above-mentioned content of silicon and aluminum may be at least one selected from the group consisting of fly ash, coal gangue and kaolin clay extracted from silicon residues.

According to the present invention, preferably, the silicon slag contains amorphous SiO ₂ in phase. Wherein, the amorphous SiO ₂ means that the SiO ₂ in the present invention mainly exists as SiO ₂ in an amorphous state.

In the present invention, preferably, the modulus of the low modulus water glass in step I) is 0.5-1.5, and the low modulus water glass can be prepared by the method of the present invention, or can be obtained commercially.

In the present invention, high modulus water glass is prepared by hydrothermal reaction. In step 1), the hydrothermal reaction temperature can be 120-200° C., the hydrothermal reaction time can be 1-6h, and the hydrothermal reaction pressure can be 0.2 -2.0MPa; in order to further improve the modulus of the prepared high modulus water glass, preferably, the hydrothermal reaction temperature can be 150-180°C, the hydrothermal reaction time can be 2.5-5h, and the hydrothermal reaction pressure It can be 0.8-1.3MPa.

Preferably, in step 1), the mass ratio of the low modulus water glass to the silicon slag is 1:(2.5-5.0).

Specifically, the hydrothermal reaction process may be uniform mixing of the low modulus water glass prepared by the method of the present invention and the silicon slag in a mass ratio of 1:(2.5-5.0), and then pouring into the hydrothermal reaction kettle , the reaction temperature is controlled by steam heating to be 120-200 ° C, the reaction pressure is 0.2-2.0 MPa, and the reaction is continued for 1-6 h. After the reaction is completed, the slurry is taken out and filtered to obtain the filtrate and the second filter residue. The filtrate has a modulus of 2.5 The high modulus water glass of -3.5, wherein the modulus and Na ₂ O content of the high modulus water glass are determined according to "GB/T4209-2008 Industrial Sodium Silicate"; the second filter residue is washed and dried to obtain Analcite with a particle size of 4 to 10 μm.

Specifically, in the washing process, water at 50-100° C. can be used for washing 2-6 times, wherein the amount of water is 3-6 times the weight of the filter residue formed by filtration; the drying process can be performed at 80-100° C. Dry for 3-10h.

The second aspect of the present invention provides a method for preparing high modulus water glass co-producing analcite from silicon slag, characterized in that the method comprises the following steps:

1) mixing silicon slag with sodium hydroxide solution to obtain mixed slurry;

2) carrying out the desiliconization reaction of the slurry, and then carrying out solid-liquid separation to obtain a low modulus water glass solution and a first filter residue;

3) using the low-modulus water glass solution according to the method for co-producing analcite with high-modulus water glass according to the present invention to obtain a high-modulus water glass solution and analcite;

Wherein, the content of SiO ₂ in the silicon slag is 50-80 wt %, and the content of Al ₂ O ₃ is 5-20 wt %.

Preferably, the content of SiO ₂ in the silicon slag is 70-80 wt %, and the content of Al ₂ O ₃ is 8-15 wt %.

According to the present invention, in order to obtain low modulus water glass, preferably, in step 1), the mass ratio of the silicon slag to the sodium hydroxide solution is 1:(3-6), and the mass of the sodium hydroxide solution is 1: (3-6). The concentration is 10%-20%.

According to the present invention, in order to prepare low modulus water glass, preferably, in step 2), the desiliconization reaction temperature is 60-120° C., and the desiliconization reaction time is 0.5-2h;

Specifically, the desiliconization reaction process may be to mix the silicon slag and the sodium hydroxide solution in a mass ratio of 1:(3-6), wherein the mass concentration of the sodium hydroxide solution is 10%-20%, and then the The uniformly mixed slurry is poured into the desiliconization reaction kettle, and the reaction temperature is controlled to be 60-120 ° C by steam heating, and the reaction is continued for 0.5-2 h. After the reaction is completed, the slurry is taken out and filtered to obtain the filtrate and the first filter residue. The filtrate is the mold Low modulus water glass with a number of 0.5-1.5, wherein the modulus of the low modulus water glass is determined according to "GB/T4209-2008 Industrial Sodium Silicate".

According to the present invention, the water glass prepared by the above method is low modulus water glass, and its modulus is 0.5-1.5, which can be further used to prepare high modulus water glass.

A third aspect of the present invention provides a method for preparing high-modulus water glass and co-producing analcite from high-alumina fly ash, characterized in that the method comprises the following steps:

a) contacting high-alumina fly ash with an acid solution to extract aluminum by acid method to obtain alumina and silicon slag;

b) Using the silicon slag to prepare high-modulus water glass co-producing anallite by the method of the present invention for preparing high-modulus water glass co-producing anallite.

According to a preferred embodiment of the present invention, the silicon slag can be obtained from the residue of high-alumina fly ash acid extraction aluminum, wherein, the acid extraction process of aluminum can be the use of sulfuric acid or hydrochloric acid to acidify the high-alumina fly ash Alumina is dissolved and extracted, and the SiO ₂ activity of the silicon slag is very high after acid leaching. In order to improve the extraction efficiency of alumina, hydrochloric acid is preferably used to extract alumina in high-alumina fly ash. Specifically, the preparation process of the silicon slag can be as follows: firstly, the high-alumina fly ash is ground with a pulverizing grinder, the particle size after grinding is in the range of 100-200 mesh, and the solid content is 25-35% by adding water. The slurry of 35-45% by weight of solid content is obtained after the magnetic field strength is 12-18,000 GS under the magnetic field strength of 12-18,000 GS. Adding hydrochloric acid with a concentration of 20-26% by weight to the filter cake to carry out acid dissolution reaction, the molar ratio of HCl in the hydrochloric acid to the alumina in the high-alumina fly ash is 2.5-3.5:1, and the reaction temperature is 100-180 ° C. The pressure is 0.3-1.0MPa, the reaction time is 1.2-3h, suction filtration, the filter cake is washed with water with a solid-liquid ratio of high-alumina fly ash and water of 0.5-2:1, and the silicon slag is obtained by filtration.

Wherein, the high-alumina fly ash comes from the wet discharge fly ash of a power plant in Inner Mongolia, and the main components are Al ₂ O ₃ 52 wt % and SiO ₂ 37 wt %.

The method for preparing high-modulus water glass and co-producing analcite provided by the high-alumina fly ash provided by the invention can improve the utilization efficiency of the high-alumina fly ash. Wherein, in step a), alumina can be produced, and the produced silicon slag can be used in step b) to prepare high-modulus water glass while co-producing analcite.

The fourth aspect of the present invention provides high modulus water glass and analcite prepared by the method of the present invention.

The present invention will be described in detail below by means of examples.

In the following examples, the modulus of water glass is determined by "GB/T4209-2008 Industrial Sodium Silicate"; the particle size of analcite is determined by a laser particle size analyzer;

The high-alumina fly ash comes from the wet discharge fly ash of Inner Mongolia Power Plant, and the main components are Al ₂ O ₃ 52% by weight and SiO ₂ 37% by weight;

The coal gangue is mined from Inner Mongolia, and the main components are Al ₂ O ₃ 31% by weight and SiO ₂ 60% by weight;

Kaolinite is mined from Inner Mongolia, and its main components are Al ₂ O ₃ 37% by weight and SiO ₂ 42% by weight;

The main phase composition of the obtained analcite was determined by XRD;

The morphological characteristics of the prepared analcite were observed by SEM;

In the following examples, the calculation method of the yield of water glass is: (SiO ₂ weight % in water glass×water glass volume×density)/(silicon slag weight×silicon slag SiO ₂ weight %).

Preparation Example 1

The high-alumina fly ash is ground with a pulverizing grinder. The particle size after grinding is in the range of 100-200 mesh, and water is added to make a slurry with a solid content of 30% by weight. A vertical ring magnetic separator is used. Magnetic separation at 15,000 GS was performed 3 times, and a filter cake with a solid content of 42 wt % was obtained after being filtered by a plate and frame filter press; hydrochloric acid with a concentration of 31 wt % was added to the filter cake to carry out acid dissolution reaction. The molar ratio of alumina in the high-alumina fly ash is 3:1, the reaction temperature is 150°C, the reaction pressure is 0.7MPa, and after the reaction time is 1.8h, suction filtration, and the filter cake uses the solid-liquid ratio of high-alumina fly ash and water Washed with 1.3:1 water, filtered to obtain silicon slag.

The content of SiO ₂ in the prepared silicon slag was 70% by weight, and the content of Al ₂ O ₃ was 15% by weight.

Preparation Example 2

The coal gangue is crushed into 5-10mm particles, and the coal gangue particles are activated by a rotary kiln. The activation temperature is 850 ° C. The activated coal gangue particles are ground by a pulverizing grinder, and the particle size range after grinding is 100. -200 mesh, add water to make a slurry with a solid content of 30% by weight, use a vertical ring magnetic separator, magnetically separate 3 times at a magnetic field strength of 15,000 GS, and filter by a plate and frame filter press to obtain a solid content of 42%. The filter cake of % by weight; adding the hydrochloric acid with a concentration of 26% by weight to the filter cake to carry out acid dissolution reaction, the molar ratio of HCl in the hydrochloric acid to the alumina in the coal gangue is 3:1, the reaction temperature is 140 ° C, and the reaction pressure is 0.6 MPa, after a reaction time of 1.5h, suction filtration, the filter cake is washed with water with a solid-liquid ratio of high-alumina fly ash to water of 1.3:1, and filtered to obtain silicon slag.

The content of SiO ₂ in the prepared silicon slag is 76% by weight, and the content of Al ₂ O ₃ is 9% by weight.

Preparation Example 3

The kaolinite is broken into 5-10mm particles, and the coal gangue particles are activated by a rotary kiln. The activation temperature is 900 ° C. The activated coal gangue particles are ground by a pulverizing grinder. 100-200 mesh, add hydrochloric acid with a concentration of 28% by weight to the kaolinite pulverized particles to carry out acid dissolution reaction, the molar ratio of HCl in the hydrochloric acid to the alumina in the kaolinite is 3:1, and the reaction temperature is 150 ℃, The reaction pressure is 0.7MPa, and the reaction time is 1.5h, then suction filtration, and the filter cake is washed with water with a solid-liquid ratio of high-alumina fly ash to water of 1.3:1, and the silicon slag is obtained by filtration.

The content of SiO ₂ in the prepared silicon slag is 80% by weight, and the content of Al ₂ O ₃ is 8% by weight.

Examples 1-5 are used to illustrate the preparation of low modulus water glass.

Example 1

The silicon slag obtained in Preparation Example 1 and the sodium hydroxide solution with a mass concentration of 15% were uniformly mixed at a mass ratio of 1:4.5 to obtain a mixed slurry, and then the mixed slurry was poured into the desiliconization reaction kettle, and the steam was passed through. The reaction temperature is controlled by heating, and the slurry is reacted at 100 ° C for 1.2 hours. After the reaction is completed, the slurry is taken out and filtered. The filtrate is low modulus water glass. The modulus of the prepared water glass was 1.1.

Example 2

The silicon slag obtained in Preparation Example 1 and the sodium hydroxide solution with a mass concentration of 10% were uniformly mixed in a mass ratio of 1:3 to obtain a mixed slurry, and then the mixed slurry was poured into the desiliconization reaction kettle, and the steam was passed through. The reaction temperature was controlled by heating, and the slurry was reacted at 60 °C for 2 hours. After the reaction was completed, the slurry was taken out and filtered. The filtrate was low modulus water glass, which was measured and prepared according to "GB/T4209-2008 Industrial Sodium Silicate". The modulus of the obtained water glass was 0.9.

Example 3

The silicon slag obtained in Preparation Example 1 and the sodium hydroxide solution with a mass concentration of 20% were uniformly mixed in a mass ratio of 1:6 to obtain a mixed slurry, and then the mixed slurry was poured into the desiliconization reaction kettle, and the steam was passed through. The reaction temperature is controlled by heating, and the slurry is reacted at 120 ° C for 0.5 h. After the reaction is completed, the slurry is taken out and filtered. The filtrate is low modulus water glass. The modulus of the prepared water glass was 1.5.

Example 4

According to the method of Example 1, the difference is: the silicon slag obtained in Preparation Example 2 is used to prepare low modulus water glass, and the modulus of the prepared water glass measured according to "GB/T4209-2008 Industrial Sodium Silicate" is 1.2 .

Example 5

According to the method of Example 1, the difference is: the silicon slag obtained in Preparation Example 3, the low modulus water glass, and the modulus of the water glass obtained by measuring according to "GB/T4209-2008 Industrial Sodium Silicate" is 1.4 .

Comparative Example 1

According to the method of Example 1, the difference is that the mass ratio of silicon slag and sodium hydroxide is 2:1. As a result, because the slurry is too viscous and the reaction efficiency is low, the modulus of the water glass obtained by filtration is only 0.4.

Examples 6-14 are used to illustrate the preparation of high modulus water glass and analcite.

Example 6

The low modulus water glass obtained in Example 1 and the silicon slag obtained in Preparation Example 1 were uniformly mixed in a mass ratio of 1:3, and then poured into a hydrothermal reaction kettle, and the reaction temperature was controlled to be 150 ° C by steam heating, and the reaction pressure was It was 1.3MPa, and the reaction was continued for 5h. After the reaction was completed, the slurry was taken out and filtered, and the filtrate was high modulus water glass. According to "GB/T4209-2008 Industrial Sodium Silicate", the modulus of the prepared water glass and the content of Na ₂ O in the water glass were measured, and the results are shown in Table 1;

The filter residue was washed 4 times with water at 80°C, and the amount of water was 4.5 times the weight of the filter residue formed by filtration. After washing, the residue was dried at 90°C for 7 hours to obtain analcite. The particle size of the obtained analcite was measured by a laser particle size analyzer, and the results are shown in Table 1.

Example 7

The low modulus water glass obtained in Example 2 and the silicon slag obtained in Preparation Example 1 were uniformly mixed at a mass ratio of 1:4, and then poured into a hydrothermal reactor, and the reaction temperature was controlled to be 180 ° C by steam heating, and the reaction pressure was The reaction was continued for 2.5h. After the reaction was over, the slurry was taken out and filtered. The filtrate was high modulus water glass. According to "GB/T4209-2008 Industrial Sodium Silicate", the modulus of the prepared water glass and the content of Na ₂ O in the water glass were measured, and the results are shown in Table 1;

The filter residue was washed three times with water at 60°C, wherein the amount of water was 3 times the weight of the filter residue formed by filtration. After washing, the residue was dried at 100°C for 5 hours to obtain analcite. The particle size of the obtained analcite was measured by a laser particle size analyzer, and the results are shown in Table 1.

Example 8

The low modulus water glass obtained in Example 3 and the silicon slag obtained in Preparation Example 1 were uniformly mixed at a mass ratio of 1:5, then poured into a hydrothermal reactor, and the reaction temperature was controlled to be 165 ° C by steam heating, and the reaction pressure was The reaction was continued for 3.5h. After the reaction was over, the slurry was taken out and filtered, and the filtrate was high modulus water glass. According to "GB/T4209-2008 Industrial Sodium Silicate", the modulus of the prepared water glass and the content of Na ₂ O in the water glass were measured, and the results are shown in Table 1;

The filter residue was washed twice with water at 100°C, wherein the amount of water was 5 times the weight of the filter residue formed by filtration. After washing, the residue was dried at 80°C for 9 hours to obtain analcite. The particle size of the obtained analcite was measured by a laser particle size analyzer, and the results are shown in Table 1.

Example 9

According to the method of Example 6, the difference is: in the hydrothermal reaction kettle, the reaction temperature is controlled by steam heating to be 120° C., the reaction pressure is 2.0 MPa, and the reaction is continued for 6 hours. The results are shown in Table 1.

Example 10

According to the method of Example 6, the difference is: in the hydrothermal reaction kettle, the reaction temperature is controlled by steam heating to be 200° C., the reaction pressure is 0.2 MPa, and the reaction is continued for 1.2 h. The results are shown in Table 1.

Example 11

According to the method of Example 6, the difference is that the low-modulus water glass is commercially available with a modulus of 1.2. The results are shown in Table 1.

Example 12

According to the method of Example 6, the difference is: the low modulus water glass obtained in Example 1 and the silicon slag obtained in Preparation Example 1 are uniformly mixed in a mass ratio of 1:6.5, and then poured into a hydrothermal reactor. The results are shown in Table 1.

Example 13

According to the method of Example 6, the difference is: the low modulus water glass obtained in Example 1 and the silicon slag obtained in Preparation Example 1 are uniformly mixed in a mass ratio of 1:1.2, and then poured into a hydrothermal reactor. The results are shown in Table 1.

Example 14

According to the method of Example 6: the difference is that the low modulus water glass obtained in Example 4 and the silicon slag obtained in Preparation Example 2 are uniformly mixed at a mass ratio of 1:3. The results are shown in Table 1.

Example 15

According to the method of Example 6: the difference is that the low modulus water glass obtained in Example 5 and the silicon slag obtained in Preparation Example 3 are uniformly mixed at a mass ratio of 1:3. The results are shown in Table 1.

Comparative Example 2

The silicon slag obtained in Preparation Example 1 and the sodium hydroxide solution with a mass concentration of 15% were uniformly mixed at a mass ratio of 1:4.5 to obtain a mixed slurry, and then the mixed slurry was poured into the desiliconization reaction kettle, and the steam was passed through. The reaction temperature was controlled by heating, and the slurry was reacted at 100 °C for 1.2 h. After the reaction was completed, all the slurry was poured into the hydrothermal reactor. The reaction temperature was controlled by steam heating to 150 °C, and the reaction pressure was 1.3 MPa. After the reaction was completed for 5h, the slurry was taken out, filtered, and the modulus of the prepared water glass was measured according to "GB/T4209-2008 Industrial Sodium Silicate", and the results are shown in Table 1;

The filter residue was washed 4 times with water at 80°C, and the amount of water was 4.5 times the weight of the filter residue formed by filtration. After washing, the residue was dried at 90°C for 7 hours to obtain analcite. The particle size of the obtained analcite was measured by a laser particle size analyzer, and the results are shown in Table 1.

Comparative Example 3

The ordinary fly ash (Al ₂ O ₃ 31 wt %, SiO ₂ 62 wt %) and sodium hydroxide solution with a mass concentration of 15% are uniformly mixed in a mass ratio of 1:4 to obtain a mixed slurry, and then the mixed The slurry was poured into the desiliconization reaction kettle, and the reaction temperature was controlled by steam heating, so that the slurry was reacted at 100 ° C for 2 hours. After the reaction was completed, the slurry was taken out, filtered, and measured according to "GB/T4209-2008 Industrial Sodium Silicate" The modulus of the prepared water glass. The results are shown in Table 1.

Table 1

It can be seen from the results in Table 1 that the method described in the present invention can prepare a high modulus water glass product by a liquid phase method, the modulus of the water glass can reach 3.5, and the Na ₂ O content in the water glass can meet the requirements of industrial liquid water At the same time, the yield of water glass reaches 69%, and the by-product analcite product realizes the full utilization of silicon slag, reduces the energy consumption for preparing high modulus water glass, and obtains high value-added products.

The preferred embodiments of the present invention have been described above in detail, however, the present invention is not limited thereto. Within the scope of the technical concept of the present invention, a variety of simple modifications can be made to the technical solutions of the present invention, including combining various technical features in any other suitable manner. These simple modifications and combinations should also be regarded as the content disclosed in the present invention. All belong to the protection scope of the present invention.

Claims (9)

1. a method for high modulus water glass co-production analcite, is characterized in that, described method comprises the steps: 1) mixing low modulus water glass solution with silicon slag and carrying out hydrothermal reaction, then carrying out solid-liquid separation to obtain high modulus water glass solution and filter residue; II) washing and drying the filter residue to obtain analcite; Wherein, the content of SiO ₂ in the silicon slag is 50-80 wt %, and the content of Al ₂ O ₃ is 5-20 wt %. 2. method according to claim 1, is characterized in that, in step 1), described hydrothermal reaction temperature is 120-200 ℃, and hydrothermal reaction time is 1-6h, and hydrothermal reaction pressure is 0.2-2.0MPa ; Preferably, the hydrothermal reaction temperature is 150-180° C., the hydrothermal reaction time is 2.5-5 h, and the hydrothermal reaction pressure is 0.8-1.3 MPa. 3. The method according to claim 1 or 2, wherein in step 1), in the silicon slag, the content of SiO ₂ is 70-80% by weight, and the content of Al ₂ O ₃ is 8-15% by weight ; Preferably, the silicon slag is selected from at least one of fly ash, coal gangue and silicon slag extracted from aluminum by kaolinite; Preferably, the silicon slag contains amorphous SiO ₂ . 4. The method according to any one of claims 1-3, wherein in step 1), the mass ratio of the low modulus water glass to the silicon slag is 1:(2.5-5.0). 5. A method for preparing high modulus water glass co-producing analcite from silicon slag, wherein the method comprises the following steps: 1) mixing silicon slag with sodium hydroxide solution to obtain mixed slurry; 2) carrying out the desiliconization reaction of the slurry, and then carrying out solid-liquid separation to obtain a low modulus water glass solution and a first filter residue; 3) high modulus water glass solution and analcite are obtained from the low modulus water glass solution according to the method for the high modulus water glass co-production analcite described in any one of claims 1-4; Wherein, the content of SiO ₂ in the silicon slag is 50-80 wt %, and the content of Al ₂ O ₃ is 5-20 wt %. 6. method according to claim 5, is characterized in that, in step 1), the mass ratio of described silicon slag and sodium hydroxide solution is 1: (3-6), the mass concentration of described sodium hydroxide solution 10%-20%. 7 . The method according to claim 5 , wherein, in step 2), the desiliconization reaction temperature is 60-120° C., and the desiliconization reaction time is 0.5-2h. 8 . 8. A method for preparing high-modulus water glass co-producing analcite with high-alumina fly ash, characterized in that the method comprises the following steps: a) contacting high-alumina fly ash with an acid solution to extract aluminum by acid method to obtain alumina and silicon slag; b) The silicon slag is used to prepare high modulus water glass to co-produce analcite by the method of any one of claims 5-8. 9. The high modulus water glass and analcite prepared by the method according to any one of claims 1-8.

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