CN109455972B

CN109455972B - Preparation method of aluminum silicate accelerator

Info

Publication number: CN109455972B
Application number: CN201811487482.2A
Authority: CN
Inventors: 王栋民; 张川川; 杨国武; 王璜琪
Original assignee: China University of Mining and Technology Beijing CUMTB
Current assignee: China University of Mining and Technology Beijing CUMTB
Priority date: 2018-12-06
Filing date: 2018-12-06
Publication date: 2020-07-31
Anticipated expiration: 2038-12-06
Also published as: CN109455972A

Abstract

The invention relates to a preparation method of an aluminum silicate accelerator, which comprises the following steps: adding soluble silicate into a solution containing a dispersing agent, preferably dropwise, to form a mixed solution; adding soluble aluminum salt into the prepared mixed solution, preferably dropwise, so as to react with the soluble silicate to generate a suspension containing aluminum silicate; and adding a setting time regulator into the aluminum silicate-containing suspension to prepare the aluminum silicate accelerator. The preparation process is simple, the process is economic and environment-friendly, and the prepared aluminum silicate accelerator can obviously shorten the quick setting time and the final setting time.

Description

Preparation method of aluminum silicate accelerator

Technical Field

The invention relates to the field of preparation of materials, in particular to a preparation method of an aluminum silicate accelerator.

Background

The accelerator is a chemical additive used for shortening the cement setting time and enabling cement concrete or mortar to be quickly set within a few minutes after being mixed, and is commonly used in quick construction projects such as sprayed concrete, rush repair, leaking stoppage and the like in projects such as tunnels, subways and the like. The production accelerator is divided into two main categories of liquid and powder. The powder accelerator mainly comprises aluminum oxide clinker, carbonate and quicklime, but generally has high alkali content and poor dispersibility in concrete mixtures, and easily causes the problems of high dust and high resilience loss in spray construction and the like. Compared with the prior art, the liquid accelerator can reduce the dust and resilience problems in spraying, can be better dispersed in concrete mixtures, and improves the spraying construction quality.

Modified sodium silicate, metaaluminate, aluminum sulfate, and the like are generally added as inorganic salt components to the liquid accelerator. However, the liquid accelerator prepared from inorganic salt components such as modified sodium silicate, metaaluminate, aluminum sulfate and the like has high concentration, the mass fraction of inorganic salt is more than 50%, the production cost is high, the stability is poor, and precipitates are easy to generate.

Disclosure of Invention

In view of the problems of the prior art, the present invention has been made, and an object of the present invention is to provide a method for preparing an aluminum silicate accelerator, which can remarkably shorten the initial setting time and the final setting time by preparing an aluminum silicate-containing suspension by a specific method and preparing the aluminum silicate accelerator by adding a setting time adjusting agent using aluminum silicate as an inorganic salt component.

The invention provides a preparation method of aluminum silicate, which comprises the following steps:

adding soluble silicate or a part of the soluble silicate to a solution containing a dispersing agent, preferably dropwise, to form a mixed solution;

adding soluble aluminum salt or the remaining portion of the soluble aluminum salt and the soluble silicate, preferably dropwise, to the resulting mixture, thereby reacting the soluble aluminum salt and the soluble silicate to produce an aluminum silicate-containing suspension; and

and adding a setting time regulator into the aluminum silicate-containing suspension to prepare the aluminum silicate accelerator.

The inventor of the application finds that the soluble silicate is added into the solution containing the dispersant preferably and dropwise added, on one hand, the dispersibility of the soluble silicate in the solvent can be improved, so that when the soluble aluminum salt is dropwise added, the soluble silicate can be fully contacted with the soluble aluminum salt, and then fully reacted under the condition of high dispersion, and finally, the prepared aluminum silicate does not contain a fibrous structure, and has better dispersibility and smaller granularity; on the other hand, because the solution already contains enough soluble silicate, the soluble aluminum salt can immediately react with the soluble silicate, and the flocculation reaction is avoided.

Meanwhile, the prepared aluminum silicate suspension with better dispersity and smaller granularity is used as an inorganic salt component, a setting time regulator is added to prepare the aluminum silicate accelerator, and the setting time regulator and Al are utilized³⁺The complexation between ions reduces Al in the solution³⁺The concentration of the ions can enable the solution to be more stable, and the setting time regulator is also beneficial to shortening the setting time of the cement.

According to the invention, a portion of the soluble silicate is preferably added, preferably dropwise, to the dispersant-containing solution to form a mixed solution; the remaining portion of the soluble silicate is then added, preferably dropwise, to the resulting mixture along with a soluble aluminum salt, to react with the soluble silicate to form aluminum silicate. Therefore, enough soluble silicate can be ensured to react with the soluble aluminum salt when the soluble aluminum salt is added, so that the flocculation reaction is effectively avoided, the reaction duration can be reduced, and the reaction efficiency is improved.

According to the invention, preferably under stirring, soluble silicate is added, preferably dropwise, to the solution containing the dispersant and/or soluble aluminum salt is added, preferably dropwise, to the resulting mixture; more preferably, the stirring operation is performed by a high-speed stirring paddle, and most preferably, the rotation speed of the high-speed stirring paddle is 900-; more preferably, the dropwise adding operation is realized by a peristaltic pump, and most preferably, the liquid outlet speed of the peristaltic pump is 0.5-3 g/min.

According to the present invention, the solution containing the soluble silicate and the solution containing the soluble aluminum salt may be dropped at the same rate or at different rates, preferably at different rates.

According to the present invention, it is preferable to continue stirring for 5 to 20 hours after adding soluble aluminum salt, preferably dropwise, to the obtained mixed solution to make the reaction more sufficient.

In some preferred embodiments of the present invention, the dispersant is selected from at least one of sodium polyacrylate, ammonium polyacrylate, and sodium hexametaphosphate; preferably, the dispersant is sodium polyacrylate.

According to the present invention, the above-mentioned specific dispersant, particularly sodium polyacrylate, has good water solubility and high polarity, and can form soluble chain anions by binding with soluble aluminum salt, and thus is adsorbed on the surface of aluminum silicate solid particles, increasing the charge on the surface of the aggregated solid particles, increasing the repulsion between particles forming steric hindrance, and improving the dispersibility of sodium polyacrylate.

In some preferred embodiments of the present invention, the soluble silicate is selected from at least one of potassium silicate, sodium silicate and ammonium silicate; preferably, the soluble silicate is sodium silicate.

According to the present invention, the potassium silicate, the sodium silicate and the ammonium silicate may be in any conventional form, and for example, the sodium silicate may be anhydrous sodium silicate, sodium silicate pentahydrate, sodium silicate nonahydrate or water glass.

In some preferred embodiments of the present invention, the soluble aluminum salt is selected from at least one of aluminum chloride, aluminum sulfate, aluminum nitrate, and aluminum sulfide; preferably, the soluble aluminium salt is aluminium sulphate.

According to the present invention, aluminum chloride, aluminum sulfate, aluminum nitrate and aluminum sulfide may be used in any conventional form, and for example, anhydrous aluminum sulfate or aluminum sulfate octadecahydrate may be used as aluminum sulfate.

In some preferred embodiments of the present invention, the mass ratio of the soluble silicate to the dispersant is (1-15):1, preferably (2-10): 1; and/or the mass ratio of the soluble silicate to the soluble aluminium salt is (1-3):1, preferably (1.8-2.3): 1.

According to the present invention, when the mass ratio of the soluble silicate to the dispersant and/or the mass ratio of the soluble silicate to the soluble aluminum salt is within the above-specified range, it is advantageous to obtain aluminum silicate having a good dispersibility and a small particle size.

In some preferred embodiments of the present invention, the concentration of the dispersant in the dispersant-containing solution is 5% to 25%, preferably 10% to 15%.

According to the invention, in the solution of the dispersant, the solvent is an alcohol organic solvent or water, preferably water; wherein the alcohol organic solution is selected from C₁-C₅At least one of the alcohols is preferably at least one of methanol, ethanol, n-propanol, isopropanol, n-butanol, sec-butanol, tert-butanol, iso-butanol and n-pentanol.

In some preferred embodiments of the invention, the soluble silicate is added to the dispersant-containing solution after dissolving in a solvent, preferably water, to form a silicate solution; and/or soluble aluminum salt is dissolved in a solvent, preferably water, to form an aluminum salt solution, and then the aluminum salt solution is added to the mixed solution.

According to the invention, a soluble silicate is dissolved in a solvent, preferably water, at a temperature of 20 ℃ to 35 ℃, preferably at room temperature, to form a silicate solution; and/or dissolving a soluble aluminium salt in a solvent, preferably water, at a temperature of from 40 ℃ to 80 ℃, preferably from 50 ℃ to 65 ℃, to form an aluminium salt solution, more preferably incubating the formed aluminium salt solution for from 0.5h to 2 h.

According to the invention, the dissolution operation carried out in the above-mentioned temperature range is advantageous for the adequate dissolution of the soluble silicate and the soluble aluminium salt and for the stability during subsequent use.

In some preferred embodiments of the present invention, the concentration of silicate in the silicate solution is 10% to 45%, preferably 25% to 30%; and/or the concentration of the aluminum salt in the aluminum salt solution is 5-35%, preferably 15-20%.

According to the present invention, when the concentration of the silicate and the concentration of the aluminum salt are within the above-specified ranges, it is advantageous to obtain aluminum silicate having a good dispersibility and a small particle size.

In some preferred embodiments of the present invention, the setting time adjuster is selected from at least one of diethanolamine, triethanolamine, triisopropanolamine, diethylenetriamine, aminoethylethanolamine, and ammonium polyvinylalcohol phosphate; preferably, the mass ratio of the coagulation time regulator to the soluble aluminum salt is (0.2-0.6):1, preferably (0.3-0.5): 1.

According to the present invention, the above-mentioned specific setting time modifier, particularly an alkanolamine compound such as diethanolamine, can be more favorably used in combination with Al³⁺The ions are complexed, which is beneficial to improving the stability of the accelerator and shortening the setting time of the cement.

Another aspect of the present invention provides an aluminum silicate accelerator prepared according to the above preparation method.

In the present invention, unless otherwise specified, "water" means deionized water, and room temperature means 25 ℃.

The initial setting time of the aluminum silicate accelerator provided by the invention is below 10min, the final setting time is below 25min, and even the initial setting time is below 4min, and the final setting time is below 10 min.

Detailed Description

The present invention will be described in detail below with reference to examples, but the scope of the present invention is not limited to the following description.

The initial setting time and the final setting time of the aluminum silicate setting accelerators prepared in examples 1 to 10 and comparative example 1 were tested according to GB/T1346-.

The apparatus used in the following examples 1-10, comparative example 1 includes but is not limited to:

electric mixer, shanghai sele instruments ltd, model: HD 2010W.

Cement paste mixer, shanghai leiyun testing instrument manufacture ltd, model: NJ-160.

Standard method vicat instrument, hebei rongda road and bridge department instrument, model: ISO.

The reagents used in the following examples 1-10, comparative example 1 include, but are not limited to:

sodium silicate nonahydrate, Shanghai Michelin Biochemical technology, Inc.;

aluminum sulfate octadecahydrate, Shanghai Michelin Biochemical technology, Inc.;

sodium polyacrylate, Shanghai Michelin Biochemical technology, Inc.;

diethanolamine, Shanghai Michelin Biochemical technology, Inc.;

triethanolamine, Shanghai Michelin Biochemical technology, Inc.;

reference cement, maurus midwifery cement limited.

Example 1

Preparing 80g of sodium polyacrylate water solution (the mass fraction of the sodium polyacrylate is 6%), and placing the sodium polyacrylate water solution in a reactor (please supplement the name, the model and the like of the reactor) as a bottom material;

dissolving 39.1g of sodium silicate nonahydrate in 20g of deionized water at room temperature to obtain 59.1g of sodium silicate solution (the mass fraction of the sodium silicate is 28%);

under the condition of water bath at 60 ℃, 19.46g of aluminum sulfate octadecahydrate is dissolved in 40g of deionized water and is kept warm for 1 hour to prepare an aluminum sulfate solution (the mass fraction of the aluminum sulfate is 16.8 percent);

then under the condition of stirring (the rotating speed of a high-speed stirring paddle is 1000rpm), dropwise adding the prepared sodium silicate solution into the sodium polyacrylate aqueous solution at the speed of 1g/min by using a peristaltic pump, and continuously stirring for 0.5h after dropwise adding is finished to prepare a suspension containing sodium silicate and sodium polyacrylate; then, dropwise adding the prepared aluminum sulfate solution into the prepared suspension at the speed of 1g/min by using a peristaltic pump, and continuously stirring for 12 hours after the dropwise adding is finished to prepare the aluminum sulfate-containing suspension (wherein the mass ratio of the sodium silicate nonahydrate to the sodium polyacrylate is 8:1, and the mass ratio of the sodium silicate nonahydrate to the aluminum sulfate octadecahydrate is 2: 1);

and finally, 6g of diethanol amine is added into the prepared aluminum silicate-containing suspension, and the mixture is stirred for 1 hour at the rotating speed of 100rpm, so that the aluminum silicate accelerator is prepared.

The prepared aluminum silicate accelerator was added to a reference cement, and the initial setting time and the final setting time thereof were measured, and the results are shown in table 1.

Example 2

Preparing 240g of sodium polyacrylate water solution (the mass fraction of the sodium polyacrylate is 13%), and placing the sodium polyacrylate water solution in a three-neck flask as a bottom material;

117.31g of sodium silicate nonahydrate is dissolved in 60g of deionized water at room temperature to prepare 177.31g of sodium silicate solution (the mass fraction of the sodium silicate is 28%);

58.38g of aluminum sulfate octadecahydrate are dissolved in 120g of deionized water under the water bath condition of 65 ℃, and the temperature is kept for 1 hour to prepare 178.38 aluminum sulfate solution (the mass fraction of the aluminum sulfate is 16.8 percent);

then under the condition of stirring (the rotating speed of a high-speed stirring paddle is 1000rpm), dropwise adding the prepared sodium silicate solution into the sodium polyacrylate aqueous solution at the speed of 1.97g/min by using a peristaltic pump, after dropwise adding for 0.5h, dropwise adding the prepared aluminum sulfate solution at the speed of 2.97g/min by using the peristaltic pump while dropwise adding the sodium silicate solution, and continuously stirring for 12h after dropwise adding is completed to prepare an aluminum silicate-containing suspension (wherein the mass ratio of sodium nonahydrate to sodium polyacrylate is 3.75:1, and the mass ratio of sodium nonahydrate to aluminum octadecahydrate is 2: 1);

and finally, adding 18g of triethanolamine into the prepared aluminum silicate-containing suspension and stirring at the rotating speed of 100rpm for 0.5h to prepare the aluminum silicate accelerator.

Example 3

Aluminum silicate was prepared in the same manner as in example 1 except that the mass fraction of sodium polyacrylate was 20%. The prepared aluminum silicate accelerator was added to a reference cement, and the initial setting time and the final setting time thereof were measured, and the results are shown in table 1.

Example 4

Aluminum silicate was prepared in the same manner as in example 1 except that the mass fraction of sodium polyacrylate was 25%. The prepared aluminum silicate accelerator was added to a reference cement, and the initial setting time and the final setting time thereof were measured, and the results are shown in table 1.

Example 5

Aluminum silicate was prepared in the same manner as in example 1 except that the mass fraction of sodium polyacrylate was 30%. The prepared aluminum silicate accelerator was added to a reference cement, and the initial setting time and the final setting time thereof were measured, and the results are shown in table 1.

Example 6

Aluminum silicate was prepared in the same manner as in example 1 except that the mass ratio of sodium silicate nonahydrate to sodium polyacrylate was 4: 1. The prepared aluminum silicate accelerator was added to a reference cement, and the initial setting time and the final setting time thereof were measured, and the results are shown in table 1.

Example 7

Aluminum silicate was prepared in the same manner as in example 1 except that the mass ratio of sodium silicate nonahydrate to aluminum sulfate octadecahydrate was 1: 1. The prepared aluminum silicate accelerator was added to a reference cement, and the initial setting time and the final setting time thereof were measured, and the results are shown in table 1.

Example 8

Aluminum silicate was prepared in the same manner as in example 1, except that "6% by mass aqueous ammonium polyacrylate solution" was used instead of the 6% by mass aqueous sodium polyacrylate solution in example 1. The prepared aluminum silicate accelerator was added to a reference cement, and the initial setting time and the final setting time thereof were measured, and the results are shown in table 1.

Example 9

An aluminum silicate was prepared in the same manner as in example 1, except that "a 28% by mass potassium silicate solution" was used instead of "a 28% by mass sodium silicate solution". The prepared aluminum silicate accelerator was added to a reference cement, and the initial setting time and the final setting time thereof were measured, and the results are shown in table 1.

Example 10

Aluminum silicate was prepared in the same manner as in example 1, except that "aluminum chloride having a mass fraction of 16.8% was used" instead of "aluminum sulfate solution having a mass fraction of 16.8%". The prepared aluminum silicate accelerator was added to a reference cement, and the initial setting time and the final setting time thereof were measured, and the results are shown in table 1.

Comparative example 1

The concrete formula of the accelerator is as follows: 18% of sodium silicate, 3% of diethanolamine and the balance of water.

The prepared sodium silicate setting accelerator was added to a reference cement, and the initial setting time and the final setting time thereof were measured, and the results are shown in table 1.

Comparative example 2

The accelerator with aluminum sulfate as an inorganic salt component is provided, and the specific formula of the accelerator with aluminum sulfate is as follows: 18% of aluminum sulfate, 3% of diethanol amine and the balance of water.

The prepared aluminum sulfate accelerator was added to a reference cement, and the initial setting time and the final setting time thereof were measured, and the results are shown in table 1.

Comparative example 3

The set time of the reference cement without the accelerator was measured and the final set time was measured, and the results are shown in Table 1.

TABLE 1

Comparing examples 1 to 10 and comparative example 3 in Table 1, it is understood that the aluminum silicate accelerator of the present application can significantly shorten the initial setting time and the final setting time of cement. Comparing examples 1 to 10 of the present application with comparative examples 1 and 2, it is understood that the aluminum silicate accelerator of the present application can shorten the initial setting time of cement more effectively and improve the final setting time of cement.

In addition, as can be seen from comparison between example 1 and comparative examples 1 and 2 of the present application, the aluminum silicate content of the accelerator can be calculated to be about 5.8% which is much lower than that of the inorganic salt component in comparative examples 1 and 2, and it can be seen that the accelerator prepared by the preparation method provided by the present application can not only significantly shorten the setting time of cement, but also reduce the usage amount of the inorganic salt component and reduce the production and use costs.

It should be noted that the above-mentioned embodiments are only for explaining the present invention, and do not constitute any limitation to the present invention. The present invention has been described with reference to exemplary embodiments, but the words which have been used herein are words of description and illustration, rather than words of limitation. The invention can be modified, as prescribed, within the scope of the claims and without departing from the scope and spirit of the invention. Although the invention has been described herein with reference to particular means, materials and embodiments, the invention is not intended to be limited to the particulars disclosed herein, but rather extends to all other methods and applications having the same functionality.

Claims

1. A preparation method of an aluminum silicate accelerator comprises the following steps:

adding soluble silicate or a part of the soluble silicate into a solution containing a dispersing agent to form a mixed solution;

adding soluble aluminum salt or the remaining portion of the soluble aluminum salt and the soluble silicate to the resulting mixture, thereby reacting the soluble aluminum salt with the soluble silicate to produce an aluminum silicate-containing suspension; and

2. The method according to claim 1, wherein the soluble silicate or a part of the soluble silicate is added dropwise to a solution containing a dispersant to form a mixed solution.

3. The production method according to claim 1, wherein a remaining part of the soluble aluminum salt or the soluble aluminum salt and the soluble silicate is added dropwise to the obtained mixed solution.

4. The method according to claim 1, wherein the dispersant is at least one selected from the group consisting of sodium polyacrylate, ammonium polyacrylate, and sodium hexametaphosphate.

5. The method of claim 4, wherein the dispersant is sodium polyacrylate.

6. The method according to any one of claims 1 to 5, wherein the soluble silicate is at least one selected from the group consisting of potassium silicate, sodium silicate and ammonium silicate.

7. The method of claim 6, wherein the soluble silicate is sodium silicate.

8. The production method according to any one of claims 1 to 5, wherein the soluble aluminum salt is selected from at least one of aluminum chloride, aluminum sulfate, aluminum nitrate, and aluminum sulfide.

9. The method according to claim 8, wherein the soluble aluminum salt is aluminum sulfate.

10. The production method according to any one of claims 1 to 5, characterized in that the mass ratio of the soluble silicate to the dispersant is (1-15): 1; and/or the mass ratio of the soluble silicate to the soluble aluminum salt is (1-3): 1.

11. The method according to claim 10, wherein the mass ratio of the soluble silicate to the dispersant is (2-10): 1; and/or the mass ratio of the soluble silicate to the soluble aluminum salt is (1.8-2.3): 1.

12. The production method according to any one of claims 1 to 5, wherein the concentration of the dispersant in the dispersant-containing solution is 5% to 25%.

13. The method according to claim 12, wherein the concentration of the dispersant in the dispersant-containing solution is 10% to 15%.

14. The production method according to any one of claims 1 to 5, characterized in that a soluble silicate is dissolved in a solvent to form a silicate solution, and then added to the dispersant-containing solution; and/or dissolving soluble aluminum salt in a solvent to form an aluminum salt solution, and then adding the aluminum salt solution into the mixed solution.

15. The method according to claim 14, wherein a soluble silicate is dissolved in water to form a silicate solution, and then the silicate solution is added to the dispersant-containing solution; and/or dissolving soluble aluminum salt in water to form an aluminum salt solution, and then adding the aluminum salt solution into the mixed solution.

16. The method according to claim 14, wherein the silicate solution has a concentration of 10% to 45%; and/or the concentration of the aluminum salt in the aluminum salt solution is 5-35%.

17. The method of claim 16, wherein the silicate solution has a silicate concentration of 25% to 30%; and/or the concentration of the aluminum salt in the aluminum salt solution is 15-20%.

18. The production method according to any one of claims 1 to 5, wherein the setting time adjuster is at least one selected from the group consisting of diethanolamine, triethanolamine, triisopropanolamine, diethylenetriamine, aminoethylethanolamine, and ammonium polyvinyl alcohol phosphate.

19. The method according to claim 18, wherein the mass ratio of the setting time adjuster to the soluble aluminum salt is (0.2-0.6): 1.

20. The method according to claim 19, wherein the mass ratio of the setting time adjuster to the soluble aluminum salt is (0.3-0.5): 1.

21. An aluminum silicate accelerator prepared according to the preparation method of any one of claims 1 to 20.