阅读说明：本技术 一种多孔粉煤灰砖及其制备方法 (Porous flyash brick and preparation method thereof ) 是由 孙伟 于 2021-08-02 设计创作，主要内容包括：本发明公开一种多孔粉煤灰砖及其制备方法,包括砖体和砖体上均匀贯穿的通孔,所述砖体分为上下两层,上层为具有微孔结构的吸附材料层,下层为粉煤灰材料层；该多孔粉煤灰砖的一个截面为长方形,边长为20-30cm；制备浆料；制备吸附材料；将吸附材料涂覆在浆料上表面,之后经过模具成型,得到湿坯体,升温至200℃,在此温度下保温2h,烧结,制得多孔粉煤灰砖基料,其中吸附材料形成吸附材料层,浆料形成粉煤灰材料层；污水经过多孔粉煤灰砖时通过特定的通孔通过,当经过吸附材料层时,对其进行吸附除杂,之后经过粉煤灰材料层,对污水中的重金属离子进行去除,使得该多孔粉煤灰砖具有优异的污水净化性能。(The invention discloses a porous flyash brick and a preparation method thereof, wherein the porous flyash brick comprises a brick body and through holes uniformly penetrating through the brick body, wherein the brick body is divided into an upper layer and a lower layer, the upper layer is an adsorption material layer with a microporous structure, and the lower layer is a flyash material layer; one section of the porous flyash brick is rectangular, and the side length is 20-30 cm; preparing slurry; preparing an adsorbing material; coating an adsorption material on the upper surface of the slurry, molding by a mold to obtain a wet blank, heating to 200 ℃, preserving heat for 2 hours at the temperature, and sintering to obtain a porous fly ash brick base material, wherein the adsorption material forms an adsorption material layer, and the slurry forms a fly ash material layer; sewage passes through specific through-hole when porous fly ash brick, when the adsorption material layer, adsorbs the edulcoration to it, later passes through the fly ash material layer, gets rid of the heavy metal ion in the sewage for this porous fly ash brick has excellent sewage purification performance.)

1. The porous fly ash brick is characterized by comprising a brick body (1) and through holes (2) uniformly penetrating through the brick body (1), wherein the brick body (1) is divided into an upper layer and a lower layer, the upper layer is an adsorption material layer (11) with a microporous structure, and the lower layer is a fly ash material layer (12);

the adsorption material layer (11) is an adsorption material, and the adsorption material is prepared by the following steps:

step S11, adding the silver nitrate solution into the calcium nitrate solution, stirring at a constant speed, adding sodium dodecyl benzene sulfonate, and continuously stirring for 10min to obtain a solution a for later use; dropwise adding an ammonium dihydrogen phosphate solution into the solution a, controlling the dropwise adding time to be 30min, adding ammonia water to adjust the pH value until the pH value is 11 after the dropwise adding is finished, then placing the solution into a reaction kettle, respectively preserving the heat at 160 ℃, 170 ℃ and 180 ℃ for reaction for 4h, aging a reaction product for 30h after the reaction is finished, centrifuging and filtering, respectively washing once with deionized water and absolute ethyl alcohol, drying and grinding to obtain powder;

and step S12, adding 20% ammonium bicarbonate solution into the prepared powder, uniformly mixing, drying for 24 hours, transferring to an oven, and keeping the temperature at 75 ℃ for drying for 5 hours to obtain the adsorbing material.

2. The porous fly ash brick of claim 1, wherein the porous fly ash brick has a rectangular cross section and the side length of the porous fly ash brick is 20-30 cm.

3. The porous fly ash brick as claimed in claim 1, wherein the volume ratio of the silver nitrate solution to the calcium nitrate solution in step S11 is 1: 1, the amount of the ammonium dihydrogen phosphate solution is 10% by volume of the solution a, the amount of the sodium dodecylbenzenesulfonate is 0.5-0.8% by mass of the solution a, and the amount of the ammonium hydrogen carbonate in step S12 is 15-20% by mass of the powder.

4. The method for preparing a porous fly ash brick according to claim 1, comprising the steps of:

step S1, mixing and stirring 45-55 parts of fly ash, 10-15 parts of expanded perlite powder, 3-5 parts of zeolite powder, 4-6 parts of furnace slag, 2-5 parts of calcium carbonate, 1-2 parts of calcium chloride and 0.1-0.5 part of potassium sulfate for 20min to prepare a mixture, crushing the mixture twice to prepare a raw material, adding water, stirring for 10min to prepare a slurry, and controlling the water content of the slurry to be 18-20%;

step S2, preparing an adsorbing material;

s3, coating an adsorption material on the upper surface of the slurry, molding by a mold to obtain a wet blank, drying at 100 ℃, introducing argon, heating to 200 ℃, preserving heat for 2 hours at the temperature, and sintering to obtain a porous fly ash brick base material, wherein the adsorption material forms an adsorption material layer (11), and the slurry forms a fly ash material layer (12);

and step S4, washing and drying the porous fly ash brick base material by using deionized water and ethanol, putting the base material into a treatment solution, heating in a water bath at 40-50 ℃, stirring at a constant speed for 36 hours, and then washing and drying for 20 hours to obtain the porous fly ash brick, wherein the weight ratio of the porous fly ash brick base material to the treatment solution is 10: 200.

5. The method for preparing a porous fly ash brick as claimed in claim 4, wherein the treating fluid is a mixture of gamma- (2, 3-glycidoxy) propyltrimethoxysilane and a 15% ethanol aqueous solution in a volume ratio of 1: 10.

6. The method of claim 4, wherein the length of the mold in step S3 is 30cm and 20cm, respectively, and the mold has a rectangular longitudinal section, and the mold has 10 uniformly distributed cylinders.

Technical Field

The invention belongs to the technical field of environment-friendly materials, and particularly relates to a porous fly ash brick and a preparation method thereof.

Background

At present, methods for purifying water quality of heavily polluted urban riverways mainly comprise riverway dredging, mechanical salvage, artificial aeration and biological restoration methods (ecological floating beds, artificial wetlands and microbial restoration). However, for the heavily polluted river channel, the concentration of the pollutants in the river channel is high due to long-term continuous pollution, the water environment quality is poor, and the ecological system is seriously damaged, so that the concentration of the pollutants in the heavily polluted river channel is difficult to reduce by the conventional physical method, and the heavily polluted river channel can only play a role of treating the symptoms but not the root causes. Although the biological method can improve water quality and ecological environment, the biological repair is difficult to directly carry out in water with high pollution concentration, low dissolved oxygen and low transparency, the effect of the biological repair technology is seriously influenced, and the technical cost is increased.

Disclosure of Invention

In order to overcome the technical problems, the invention provides a porous fly ash brick and a preparation method thereof.

The purpose of the invention can be realized by the following technical scheme:

a porous fly ash brick comprises a brick body and through holes uniformly penetrating through the brick body, wherein the brick body is divided into an upper layer and a lower layer, the upper layer is an adsorption material layer with a microporous structure, and the lower layer is a fly ash material layer;

the adsorption material layer is an adsorption material, and the adsorption material is prepared by the following steps:

step S11, adding a silver nitrate solution with the concentration of 0.150mol/L into a calcium nitrate solution with the concentration of 0.1mol/L, stirring at a constant speed, adding sodium dodecyl benzene sulfonate, and continuously stirring for 10min to prepare a solution a for later use; dropwise adding an ammonium dihydrogen phosphate solution into the solution a, controlling the dropwise adding time to be 30min, adding ammonia water to adjust the pH value until the pH value is 11 after the dropwise adding is finished, then placing the solution into a reaction kettle, respectively preserving the heat at 160 ℃, 170 ℃ and 180 ℃ for reaction for 4h, aging a reaction product for 30h after the reaction is finished, centrifuging and filtering, respectively washing once with deionized water and absolute ethyl alcohol, drying and grinding to obtain powder;

and step S12, adding an ammonium bicarbonate solution with the mass fraction of 20% into the prepared powder, uniformly mixing, drying for 24 hours, transferring into an oven, and keeping the temperature at 75 ℃ for drying for 5 hours to prepare the adsorbing material.

Furthermore, one section of the porous flyash brick is rectangular, and the side length is 20-30 cm.

Further, the volume ratio of the silver nitrate solution to the calcium nitrate solution in the step S11 is 1: 1, the dosage of the ammonium dihydrogen phosphate solution is 10% of the volume of the solution a, the dosage of the sodium dodecyl benzene sulfonate is 0.5-0.8% of the mass of the solution a, and the dosage of the ammonium hydrogen carbonate in the step S12 is 15-20% of the mass of the powder.

A preparation method of the porous fly ash brick comprises the following steps:

step S1, mixing and stirring 45-55 parts of fly ash, 10-15 parts of expanded perlite powder, 3-5 parts of zeolite powder, 4-6 parts of furnace slag, 2-5 parts of calcium carbonate, 1-2 parts of calcium chloride and 0.1-0.5 part of potassium sulfate for 20min to prepare a mixture, crushing the mixture twice to prepare a raw material, adding water, stirring for 10min to prepare a slurry, and controlling the water content of the slurry to be 18-20%;

step S2, preparing an adsorbing material;

step S3, coating an adsorption material on the upper surface of the slurry, molding through a mold to obtain a wet blank, drying at 100 ℃, introducing argon, heating to 200 ℃, preserving heat for 2 hours at the temperature, and sintering to obtain a porous fly ash brick base material, wherein the adsorption material forms an adsorption material layer, and the slurry forms a fly ash material layer;

and step S4, washing and drying the porous fly ash brick base material by using deionized water and ethanol, putting the base material into a treatment solution, heating in a water bath at 40-50 ℃, stirring at a constant speed for 36 hours, and then washing and drying for 20 hours to obtain the porous fly ash brick, wherein the weight ratio of the porous fly ash brick base material to the treatment solution is 10: 200.

Furthermore, the treatment liquid is formed by mixing gamma- (2, 3-epoxypropoxy) propyl trimethoxy silane and ethanol water solution with the volume fraction of 15% according to the volume ratio of 1: 10.

Further, the length of the mold in step S3 is 30cm and 20cm, respectively, wherein the longitudinal section of the mold is rectangular, and the mold is provided with uniformly distributed columns, and the number of the columns is 10.

The invention has the beneficial effects that:

in the invention, in the step S1, raw materials are mixed to prepare slurry, then in the step S2, an adsorbing material is prepared, silver nitrate solution and calcium nitrate solution are mixed, ammonium dihydrogen phosphate is added, powder loaded with silver ions is prepared by a hydrothermal synthesis method, in the step S3, the powder is uniformly coated on the upper surface of the slurry, then sintering is carried out at different temperatures to prepare a porous flyash brick base material, ammonium bicarbonate in the powder loaded with silver ions is used as a pore-forming agent, sintering decomposition is carried out to prepare porous ceramic which contains silver ions and is rich in pore channels, the porous ceramic has a large specific surface area and has strong adsorption performance, a porous structure can efficiently release silver ions and improve antibacterial performance, then in the step S4, the porous flyash brick base material is placed in a treating fluid, and gamma- (2, 3-epoxypropoxy) propyl trimethoxy silane is combined with a large amount of hydroxyl groups on the surface of a flyash material layer, the porous fly ash brick is characterized in that Si-O-Si bonds are formed and then attached to the side surface of the fly ash material layer, wherein grafted amino groups have excellent complexing effect on heavy metal ions and further can remove the heavy metal ions in the environment, so that sewage passes through specific through holes when passing through the porous fly ash brick, and is adsorbed and decontaminated when passing through the adsorption material layer, and then the heavy metal ions in the sewage are removed through the fly ash material layer, so that the porous fly ash brick has excellent sewage purification performance, and therefore the porous fly ash brick has excellent purification effect when being applied to a sewage river.

Drawings

In order to facilitate understanding for those skilled in the art, the present invention will be further described with reference to the accompanying drawings.

FIG. 1 is a cross-sectional view of a porous fly ash brick of the present invention.

In the figure: 1. a brick body; 11. a layer of adsorbent material; 12. a fly ash material layer; 2. and a through hole.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1

The adsorbing material is prepared by the following steps:

step S11, adding a silver nitrate solution with the concentration of 0.150mol/L into a calcium nitrate solution with the concentration of 0.1mol/L, stirring at a constant speed, adding sodium dodecyl benzene sulfonate, and continuously stirring for 10min to prepare a solution a for later use; dropwise adding an ammonium dihydrogen phosphate solution into the solution a, controlling the dropwise adding time to be 30min, adding ammonia water to adjust the pH value after the dropwise adding is finished until the pH value is 11, then placing the solution into a reaction kettle, carrying out heat preservation reaction at 160 ℃, 170 ℃ and 180 ℃ for 4h, aging a reaction product for 30h after the reaction is finished, centrifuging and filtering the solution, washing the solution once with deionized water and absolute ethyl alcohol respectively, drying and grinding the solution to obtain powder, wherein the volume ratio of a silver nitrate solution to a calcium nitrate solution is 1: 1, the amount of the ammonium dihydrogen phosphate solution is 10% of the volume of the solution a, and the amount of sodium dodecyl benzene sulfonate is 0.5% of the mass of the solution a;

and step S12, adding an ammonium bicarbonate solution with the mass fraction of 20% into the prepared powder, uniformly mixing, drying for 24 hours, transferring into an oven, and keeping the temperature at 75 ℃ for drying for 5 hours to prepare the adsorbing material, wherein the using amount of the ammonium bicarbonate is 15% of the mass of the powder.

Example 2

The adsorbing material is prepared by the following steps:

step S11, adding a silver nitrate solution with the concentration of 0.150mol/L into a calcium nitrate solution with the concentration of 0.1mol/L, stirring at a constant speed, adding sodium dodecyl benzene sulfonate, and continuously stirring for 10min to prepare a solution a for later use; dropwise adding an ammonium dihydrogen phosphate solution into the solution a, controlling the dropwise adding time to be 30min, adding ammonia water to adjust the pH value after the dropwise adding is finished until the pH value is 11, then placing the solution into a reaction kettle, carrying out heat preservation reaction at 160 ℃, 170 ℃ and 180 ℃ for 4h, aging a reaction product for 30h after the reaction is finished, centrifuging and filtering the solution, washing the solution once with deionized water and absolute ethyl alcohol respectively, drying and grinding the solution to obtain powder, wherein the volume ratio of a silver nitrate solution to a calcium nitrate solution is 1: 1, the amount of the ammonium dihydrogen phosphate solution is 10% of the volume of the solution a, and the amount of sodium dodecyl benzene sulfonate is 0.6% of the mass of the solution a;

and step S12, adding an ammonium bicarbonate solution with the mass fraction of 20% into the prepared powder, uniformly mixing, drying for 24 hours, transferring into an oven, and keeping the temperature at 75 ℃ for drying for 5 hours to prepare the adsorbing material, wherein the using amount of the ammonium bicarbonate is 18% of the mass of the powder.

Example 3

The adsorbing material is prepared by the following steps:

step S11, adding a silver nitrate solution with the concentration of 0.150mol/L into a calcium nitrate solution with the concentration of 0.1mol/L, stirring at a constant speed, adding sodium dodecyl benzene sulfonate, and continuously stirring for 10min to prepare a solution a for later use; dropwise adding an ammonium dihydrogen phosphate solution into the solution a, controlling the dropwise adding time to be 30min, adding ammonia water to adjust the pH value after the dropwise adding is finished until the pH value is 11, then placing the solution into a reaction kettle, carrying out heat preservation reaction at 160 ℃, 170 ℃ and 180 ℃ for 4h, aging a reaction product for 30h after the reaction is finished, centrifuging and filtering the solution, washing the solution once with deionized water and absolute ethyl alcohol respectively, drying and grinding the solution to obtain powder, wherein the volume ratio of a silver nitrate solution to a calcium nitrate solution is 1: 1, the amount of the ammonium dihydrogen phosphate solution is 10% of the volume of the solution a, and the amount of sodium dodecyl benzene sulfonate is 0.8% of the mass of the solution a;

and step S12, adding an ammonium bicarbonate solution with the mass fraction of 20% into the prepared powder, uniformly mixing, drying for 24 hours, transferring into an oven, and keeping the temperature at 75 ℃ for drying for 5 hours to prepare the adsorbing material, wherein the using amount of the ammonium bicarbonate is 20% of the mass of the powder.

Comparative example 1

Activated carbon.

2g of the adsorbing materials of examples 1 to 3 and comparative example 1 were added into a conical flask with a plug, 40mL of which was simulated by methylene blue at 15mg/L, and the flask was shaken in a constant temperature shaker at 25 ℃ for 15min, and the decolorization rate was measured, and the results are shown in the following table 1:

TABLE 1

	Example 1	Example 2	Example 3	Comparative example 1
					The removal rate is%	93.58	93.60	93.56	81.50

As can be seen from Table 1 above, the decolorization ratio for examples 1-3 is 93.56-93.60%, and for comparative example 1 is 81.50%.

Example 4

Referring to fig. 1, the porous fly ash brick of the present invention comprises a brick body 1 and through holes 2 uniformly penetrating through the brick body 1, wherein the brick body 1 is divided into an upper layer and a lower layer, the upper layer is an adsorption material layer 11 with a microporous structure, and the lower layer is a fly ash material layer 12;

the porous fly ash brick is prepared by the following steps:

step S1, mixing and stirring 45 parts of fly ash, 10 parts of expanded perlite powder, 3 parts of zeolite powder, 4 parts of furnace slag, 2 parts of calcium carbonate, 1 part of calcium chloride and 0.1 part of potassium sulfate for 20min to prepare a mixture, crushing the mixture twice, wherein the time of the first crushing is 1min, the time of the second crushing is 2min, sieving the mixture by a roller sieve with the aperture of 2mm to prepare a raw material, adding water, and stirring for 10min to prepare a slurry, wherein the water content of the slurry is controlled to be 18%;

step S2 of preparing an adsorbent according to example 1;

step S3, coating an adsorption material on the upper surface of the slurry, molding by a mold to obtain a wet blank, drying at 100 ℃, introducing argon, heating to 200 ℃, keeping the temperature for 2 hours, continuing heating to 500 ℃, keeping the temperature for 2 hours, finally heating to 750 ℃, keeping the temperature for 2 hours to prepare a porous fly ash brick base material, wherein the adsorption material forms an adsorption material layer 11, the slurry forms a fly ash material layer 12, the length of the mold is respectively 30cm and 20cm, the longitudinal section of the mold is rectangular, uniform cylinders are arranged in the mold, and the number of the cylinders is 10;

and step S4, washing and drying the porous fly ash brick base material by using deionized water and ethanol, putting the washed and dried porous fly ash brick base material into treatment liquid, heating the base material in water bath at 40 ℃, stirring the base material at a constant speed for 36 hours, and then washing and drying the base material for 20 hours to obtain the porous fly ash brick, wherein the weight ratio of the porous fly ash brick base material to the treatment liquid is 10: 200.

The treatment fluid is formed by mixing gamma- (2, 3-epoxypropoxy) propyl trimethoxy silane and ethanol water solution with volume fraction of 15% according to the volume ratio of 1: 10.

Example 5

A porous fly ash brick comprises a brick body 1 and through holes 2 uniformly penetrating through the brick body 1, wherein the brick body 1 is divided into an upper layer and a lower layer, the upper layer is an adsorption material layer 11 with a microporous structure, and the lower layer is a fly ash material layer 12;

the porous fly ash brick is prepared by the following steps:

step S1, mixing and stirring 50 parts of fly ash, 12 parts of expanded perlite powder, 4 parts of zeolite powder, 5 parts of furnace slag, 3 parts of calcium carbonate, 1 part of calcium chloride and 0.3 part of potassium sulfate for 20min to obtain a mixture, crushing the mixture twice to obtain a raw material, adding water, stirring for 10min to obtain a slurry, and controlling the water content of the slurry to be 19%;

step S2 of preparing an adsorbent according to example 1;

step S3, coating an adsorption material on the upper surface of the slurry, molding by a mold to obtain a wet blank, drying at 100 ℃, introducing argon, heating to 200 ℃, keeping the temperature for 2 hours, continuing heating to 500 ℃, keeping the temperature for 2 hours, finally heating to 750 ℃, keeping the temperature for 2 hours to prepare a porous fly ash brick base material, wherein the adsorption material forms an adsorption material layer 11, the slurry forms a fly ash material layer 12, the length of the mold is respectively 30cm and 20cm, the longitudinal section of the mold is rectangular, uniform cylinders are arranged in the mold, and the number of the cylinders is 10;

and step S4, washing and drying the porous fly ash brick base material by using deionized water and ethanol, putting the washed and dried porous fly ash brick base material into treatment liquid, heating the base material in water bath at 40 ℃, stirring the base material at a constant speed for 36 hours, and then washing and drying the base material for 20 hours to obtain the porous fly ash brick, wherein the weight ratio of the porous fly ash brick base material to the treatment liquid is 10: 200.

The treatment fluid is formed by mixing gamma- (2, 3-epoxypropoxy) propyl trimethoxy silane and ethanol water solution with volume fraction of 15% according to the volume ratio of 1: 10.

Example 6

A porous fly ash brick comprises a brick body 1 and through holes 2 uniformly penetrating through the brick body 1, wherein the brick body 1 is divided into an upper layer and a lower layer, the upper layer is an adsorption material layer 11 with a microporous structure, and the lower layer is a fly ash material layer 12;

the porous fly ash brick is prepared by the following steps:

step S1, mixing and stirring 55 parts of fly ash, 15 parts of expanded perlite powder, 5 parts of zeolite powder, 6 parts of furnace slag, 5 parts of calcium carbonate, 2 parts of calcium chloride and 0.5 part of potassium sulfate for 20min to obtain a mixture, crushing the mixture twice to obtain a raw material, adding water, stirring for 10min to obtain a slurry, and controlling the water content of the slurry to be 20%;

step S2 of preparing an adsorbent according to example 1;

step S3, coating an adsorption material on the upper surface of the slurry, molding by a mold to obtain a wet blank, drying at 100 ℃, introducing argon, heating to 200 ℃, keeping the temperature for 2 hours, continuing heating to 500 ℃, keeping the temperature for 2 hours, finally heating to 750 ℃, keeping the temperature for 2 hours to prepare a porous fly ash brick base material, wherein the adsorption material forms an adsorption material layer 11, the slurry forms a fly ash material layer 12, the length of the mold is respectively 30cm and 20cm, the longitudinal section of the mold is rectangular, uniform cylinders are arranged in the mold, and the number of the cylinders is 10;

and step S4, washing and drying the porous fly ash brick base material by using deionized water and ethanol, putting the washed and dried porous fly ash brick base material into treatment liquid, heating the base material in a water bath at 50 ℃ and stirring the mixture at a constant speed for 36 hours, and then washing and drying the mixture for 20 hours to obtain the porous fly ash brick, wherein the weight ratio of the porous fly ash brick base material to the treatment liquid is 10: 200.

The treatment fluid is formed by mixing gamma- (2, 3-epoxypropoxy) propyl trimethoxy silane and ethanol water solution with volume fraction of 15% according to the volume ratio of 1: 10.

Comparative example 2

The comparative example is a Shandong Huatong sintered flyash brick.

The fly ash bricks prepared in the examples 4 to 6 are tested for the adsorption performance of heavy metal ions according to the test standard of CN 201810501956.8; the compressive strength of the brick is tested according to GB13544-2000 sintered perforated brick, and the results are shown in the following table:

from Table 2 above, it can be seen that examples 4-6 are directed to Cd³⁺The adsorption capacity is 365-²⁺The adsorption capacity is 620-624(mg/g), the compressive strength grade is MU20, and comparative example 2 is for Cd³⁺The adsorption capacity was 26(mg/g) for Pb²⁺The adsorption capacity is 75(mg/g), and the compressive strength grade is MU20, so the fly ash brick prepared by the invention has excellent heavy metal ion adsorption performance on the basis of not influencing the strength.

In the description herein, references to the description of "one embodiment," "an example," "a specific example" or the like are intended to mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

The foregoing is illustrative and explanatory only and is not intended to be exhaustive or to limit the invention to the precise embodiments described, and various modifications, additions, and substitutions may be made by those skilled in the art without departing from the scope of the invention or exceeding the scope of the claims.