阅读说明：本技术 一种改性纳米碳酸钙的制备方法 (Preparation method of modified nano calcium carbonate ) 是由 赵小英 于 2021-10-08 设计创作，主要内容包括：本发明涉及碳酸钙生产技术领域,尤其涉及一种改性纳米碳酸钙的制备方法,包括如下步骤：生石灰和水按比例混合,加入螯合剂,反应制得石灰浆,对石灰浆进行震荡,并将石灰浆的固态颗粒含量调节至10％-15％；制备改性剂；将乙烯基三乙氧基硅烷、磷酸酯和去离子水按照6:1:3的比例进行制备,形成离子表面活性剂；对进行静置,静置完毕后向溶液内加入二氧化碳,对溶液进行气化,从而制备得到纳米碳酸钙悬浮液；真空干燥后得到纳米碳酸钙。本发明通过设置整体操作设备,改善了该方法的工艺流程,减少了需要使用的制备设备,降低了改性纳米碳酸钙制备时对化工工作者的操作要求,提高了改性纳米碳酸钙生产的整体产量。(The invention relates to the technical field of calcium carbonate production, in particular to a preparation method of modified nano calcium carbonate, which comprises the following steps: mixing quicklime and water in proportion, adding a chelating agent, reacting to obtain lime slurry, vibrating the lime slurry, and adjusting the solid particle content of the lime slurry to 10-15%; preparing a modifier; preparing vinyl triethoxysilane, phosphate and deionized water according to the ratio of 6:1:3 to form an ionic surfactant; standing, adding carbon dioxide into the solution after standing, and gasifying the solution to prepare the nano calcium carbonate suspension; vacuum drying to obtain the nano calcium carbonate. The invention improves the process flow of the method, reduces the preparation equipment required, reduces the operation requirement on chemical workers during the preparation of the modified nano calcium carbonate and improves the overall yield of the production of the modified nano calcium carbonate by arranging the overall operation equipment.)

1. The preparation method of the modified nano calcium carbonate is characterized by comprising the following steps:

s1, mixing quicklime and water in proportion, adding a chelating agent, reacting to obtain lime slurry, vibrating the lime slurry, and adjusting the solid particle content of the lime slurry to 10-15%;

s2, preparing a modifier; preparing vinyl triethoxysilane, phosphate and deionized water according to the ratio of 6:1:3 to form an ionic surfactant;

s3, adding the ionic surfactant prepared in the S2 into the lime slurry prepared in the S1, and shaking the mixed solution;

s4, standing the mixed solution after the shaking of S3 is finished, adding carbon dioxide into the solution after the standing is finished, and gasifying the solution to prepare a nano calcium carbonate suspension;

s5, drying the nano calcium carbonate suspension, grinding and filtering the dried particles, and drying in vacuum to obtain the nano calcium carbonate.

2. The preparation method of the modified nano calcium carbonate according to claim 1, wherein the preparation equipment used for realizing the method comprises a frame (1), a workbench component (2), a centrifugal component (3), a vibration storage component (4), a gas filling component (5), a first connecting line (32), a second connecting line (33) and a control module (6); the centrifugal assembly (3), the vibration storage assembly (4) and the air-entrapping assembly (5) are arranged on the rack (1); the workbench component (2) is arranged on the centrifugal component (3); the oscillation storage component (4) is in communication connection with the workbench component (2) through a first connecting wire (32); the gas filling assembly (5) is in communication connection with the workbench assembly (2) through a second connecting wire (33).

3. The method for preparing modified nano calcium carbonate according to claim 2 is characterized in that the method is implemented in a preparation device, wherein the workbench component (2) comprises a workbench (7) and a communication connector (8); the control module (6) is arranged on the workbench (7); the communication connecting piece (8) is arranged on the workbench (7); the first connecting wire (32) and the second connecting wire (33) are arranged on the communication connecting piece (8).

4. The preparation method of modified nano calcium carbonate according to claim 2, characterized in that, in the preparation equipment used for realizing the method, the centrifugal component (3) comprises a centrifugal bin (9), a centrifuge (12), a test tube mounting rack I (13) and a centrifugal heating element (14); the centrifugal bin (9) is arranged on the frame (1); the centrifugal machine (12) is arranged on the centrifugal bin (9); the test tube mounting rack I (13) is arranged on the centrifuge (12); the centrifugal heating element (14) is arranged on the centrifugal bin (9), and the centrifugal heating element (14) is positioned below the centrifugal machine (12).

5. The method for preparing modified nano calcium carbonate according to claim 4, wherein the method is implemented in a preparation device, the centrifugal assembly (3) further comprises a sliding plate (10) and a linear module (11); the linear module (11) is arranged on the centrifugal bin (9); the sliding plate (10) is arranged on the linear module (11), and the sliding plate (10) is arranged on the centrifugal bin (9) in a sliding mode.

6. The method for preparing modified nano calcium carbonate according to claim 4, characterized in that, in the preparation equipment used for realizing the method, the centrifugal assembly (3) further comprises a heat insulation plate (15); the heat insulation plate (15) is arranged at one end of the centrifugal bin (9) close to the workbench component (2).

7. The preparation method of modified nano calcium carbonate according to claim 2, wherein in the preparation equipment used for realizing the method, the oscillation storage component (4) comprises an oscillation bin (16), an oscillation machine, a cover plate (23), a constant temperature bin (24), a constant temperature heating element (25) and a test tube mounting rack III (26); the vibration bin (16) is arranged on the rack (1); the cover plate (23) is arranged on the vibration bin (16) in a vibration mode; the oscillating machine is arranged in the oscillating bin (16); the constant temperature bin (24) is arranged on the rack (1); the test tube mounting rack III (26) is arranged on the constant temperature bin (24); and is positioned at one side of the oscillating machine; the constant temperature heating element (25) is arranged on the constant temperature bin (24) and is positioned below the test tube mounting rack III (26).

8. The preparation method of modified nano calcium carbonate according to claim 7, wherein the preparation equipment used for realizing the method comprises a first rotating base (17), a cylinder (18), a rotating frame (19), a rotating piece (20), a second test tube mounting rack (21) and a second rotating base (22); the first rotating seat (17) is rotatably arranged on the oscillating bin (16); the cylinder body end of the cylinder (18) is arranged on the first rotating seat (17); the second rotating seat (22) is arranged at the piston end of the cylinder (18); the test tube mounting rack II (21) is arranged on the rotating seat II (22); the rotating frame (19) driven by the rotating piece (20) is rotatably arranged on the second test tube mounting frame (21).

9. The preparation method of the modified nano calcium carbonate according to claim 2, wherein the preparation equipment used for realizing the method is characterized in that the air-adding assembly (5) comprises an air-adding bin (27), an air-adding heating element (28), a test tube mounting rack four (29), an air tank (30) and an air-adding pipe (31); the air adding bin (27) is arranged on the frame (1); the gas-filling heating element (28) is arranged on the gas-filling bin (27); the test tube mounting rack IV (29) is arranged on the gas filling bin (27) and is positioned above the gas filling heating element (28); the air tank (30) is arranged on the air charging bin (27); the gas filling pipe (31) is provided on the gas tank (30).

10. The method for preparing modified nano calcium carbonate according to claim 1, wherein the method is carried out in the apparatus according to any one of claims 2 to 8 by the following steps:

s1, controlling the temperature of the centrifugal heating element (14), the constant-temperature heating element (25) and the air-entrapping heating element (28) by using the control module (6);

s2, placing quicklime and water in a test tube according to a proportion, adding a chelating agent into the test tube, placing the test tube on a second test tube mounting rack (21), and reacting to obtain lime slurry; the rotating piece (20) works to drive the test tube and the second embassy mounting rack (21) to rotate on the rotating frame (19), so that the lime slurry is vibrated, and the solid particle content of the lime slurry is adjusted to 10% -15%;

s3, preparing a modifier; adding vinyl triethoxysilane, phosphate and deionized water into a test tube according to the proportion of 6:1:3 for preparation to form an ionic surfactant;

s4, adding the ionic surfactant prepared in the S3 into the lime slurry prepared in the S1, and placing the mixed solution on a centrifuge (12) for shaking and centrifugation to obtain a mixed solution;

s5, placing the test tube in a constant temperature bin (24), standing the mixed solution after the S4 oscillation is finished, placing the test tube on a test tube mounting rack IV (29) after the standing is finished, adding carbon dioxide into the solution, and gasifying the solution to prepare the nano calcium carbonate suspension;

s6, drying the nano calcium carbonate suspension, grinding and filtering the dried particles, and drying in vacuum to obtain the nano calcium carbonate.

Technical Field

The invention relates to the technical field of calcium carbonate production, in particular to a preparation method of modified nano calcium carbonate.

Background

The invention with the application number of CN202010347297.4 discloses a preparation method of modified nano calcium carbonate, which comprises the steps of firstly stirring and mixing quicklime and water in proportion, then adding EDTA, continuing stirring, sieving with a 150-200 mesh sieve, and filtering to remove slag to obtain lime slurry for later use; then mixing tannic acid and deionized water to obtain a solution A, adding polyvinyl alcohol into the solution A under the stirring condition, and heating to obtain hydrogel; mixing the lime slurry and the hydrogel to obtain a mixed solution B, adding carbon dioxide into the mixed solution B for a carbonization reaction, heating the mixed solution B to 50-60 ℃ for a constant temperature, adding stearic acid, urea and starch into the mixed solution B, stirring and mixing for 2-5 hours, filtering and drying to obtain modified nano calcium carbonate; the method is convenient for improving and controlling the crystal form of the nano calcium carbonate product, and the obtained nano calcium carbonate product has large specific surface area and is loose and porous.

However, the above prior art has the following drawbacks: the method has complex flow, more preparation equipment is needed, the requirement on chemical workers is higher, if errors occur in the preparation flow, the production of the nano calcium carbonate fails, waste is caused, and the production efficiency and the yield of the nano calcium carbonate are not improved.

Disclosure of Invention

The invention provides a preparation method of modified nano calcium carbonate aiming at the technical problems in the background technology.

The technical scheme of the invention is as follows: a preparation method of modified nano calcium carbonate comprises the following steps:

s1, mixing quicklime and water in proportion, adding a chelating agent, reacting to obtain lime slurry, vibrating the lime slurry, and adjusting the solid particle content of the lime slurry to 10-15%;

s2, preparing a modifier; preparing vinyl triethoxysilane, phosphate and deionized water according to the ratio of 6:1:3 to form an ionic surfactant;

s3, adding the ionic surfactant prepared in the S2 into the lime slurry prepared in the S1, and shaking the mixed solution;

s4, standing the mixed solution after the shaking of S3 is finished, adding carbon dioxide into the solution after the standing is finished, and gasifying the solution to prepare a nano calcium carbonate suspension;

s5, drying the nano calcium carbonate suspension, grinding and filtering the dried particles, and drying in vacuum to obtain the nano calcium carbonate.

Preferably, the preparation equipment used for realizing the method comprises a frame, a workbench assembly, a centrifugal assembly, a vibration storage assembly, an air-entrapping assembly, a first connecting wire, a second connecting wire and a control module; the centrifugal assembly, the vibration storage assembly and the gas filling assembly are arranged on the frame; the workbench component is arranged on the centrifugal component; the vibration storage assembly is in communication connection with the workbench assembly through a first connecting line; the gas filling assembly is in communication connection with the workbench assembly through a second connecting line.

Preferably, in the preparation equipment used for realizing the method, the workbench component comprises a workbench and a communication connector; the control module is arranged on the workbench; the communication connecting piece is arranged on the workbench; the first connecting wire and the second connecting wire are arranged on the communication connecting piece.

Preferably, in the preparation equipment used for realizing the method, the centrifugal assembly comprises a centrifugal bin, a centrifuge, a test tube mounting rack I and a centrifugal heating element; the centrifugal bin is arranged on the frame; the centrifugal machine is arranged on the centrifugal bin; the first test tube mounting rack is arranged on the centrifuge; the centrifugal heating member is arranged on the centrifugal bin, and the centrifugal heating member is positioned below the centrifugal machine.

Preferably, in the preparation equipment used for realizing the method, the centrifugal assembly further comprises a sliding plate and a linear module; the linear module is arranged on the centrifugal bin; the sliding plate is arranged on the linear module and is arranged on the centrifugal bin in a sliding manner; the centrifugal assembly further comprises a heat insulation plate; the heat insulation plate is arranged at one end of the centrifugal bin close to the workbench component.

Preferably, in the preparation equipment used for realizing the method, the vibration storage component comprises a vibration bin, a vibration machine, a cover plate, a constant temperature bin, a constant temperature heating element and a test tube mounting rack; the vibration bin is arranged on the frame; the cover plate is arranged on the vibration bin in a vibration mode; the oscillating machine is arranged in the oscillating bin; the constant temperature bin is arranged on the frame; the test tube mounting rack III is arranged on the constant temperature bin; and is positioned at one side of the oscillating machine; the constant temperature heating member sets up on the constant temperature storehouse, and is located the below of test tube mounting bracket three.

Preferably, in the preparation equipment used for realizing the method, the shaking machine comprises a rotating seat I, a cylinder, a rotating frame, a rotating part, a test tube mounting frame II and a rotating seat II; the first rotating seat is rotatably arranged on the oscillating bin; the cylinder body end of the cylinder is arranged on the first rotating seat; the second rotating seat is arranged at the piston end of the cylinder; the test tube mounting rack II is arranged on the rotating seat II; the rotating frame driven by the rotating piece is rotatably arranged on the test tube mounting frame II.

Preferably, in the preparation equipment used for realizing the method, the gas filling assembly comprises a gas filling bin, a gas filling heating element, a test tube mounting rack IV, a gas tank and a gas filling pipe; the air adding bin is arranged on the frame; the gas-filling heating element is arranged on the gas-filling bin; the test tube mounting rack IV is arranged on the gas filling bin and is positioned above the gas filling heating element; the gas tank is arranged on the gas adding bin; the gas filling pipe is arranged on the gas tank.

The operation steps of the device are as follows:

s1, controlling the temperature of the centrifugal heating element, the constant-temperature heating element and the gas-filling heating element by using the control module;

s2, placing quicklime and water in a test tube according to a proportion, adding a chelating agent into the test tube, placing the test tube on a second test tube mounting rack, and reacting to obtain lime slurry; the rotating piece works to drive the test tube and the second embassy mounting rack to rotate on the rotating frame, so that the lime slurry is vibrated, and the solid particle content of the lime slurry is adjusted to be percent;

s3, preparing a modifier; adding vinyltriethoxysilane, phosphate and deionized water into a test tube according to the proportion to prepare an ionic surfactant;

s4, adding the ionic surfactant prepared by the S into the lime slurry prepared by the S, and placing the mixed solution on a centrifuge for shaking centrifugation to obtain a mixed solution;

s5, placing the test tube in a constant-temperature bin, standing the mixed solution after S oscillation, placing the test tube on a test tube mounting rack IV after standing, adding carbon dioxide into the solution, and gasifying the solution to prepare the nano calcium carbonate suspension;

s6, drying the nano calcium carbonate suspension, grinding and filtering the dried particles, and drying in vacuum to obtain the nano calcium carbonate.

Compared with the prior art, the technical scheme of the invention has the following beneficial technical effects: by arranging the integral operation equipment, the process flow of the method is improved, the preparation equipment required to be used is reduced, the operation requirement on chemical workers during the preparation of the modified nano calcium carbonate is reduced, the integral yield of the production of the modified nano calcium carbonate is improved, and the purity of the modified nano calcium carbonate is improved by adjusting the modifier, so that the improvement of the production efficiency and the production quality standard of the nano calcium carbonate is facilitated.

Drawings

Fig. 1 is a schematic structural diagram of an embodiment of the present invention.

FIG. 2 is a cross-sectional view of one embodiment of the present invention.

Fig. 3 is a partially enlarged structural diagram of a portion a in fig. 2.

Fig. 4 is a partially enlarged structural diagram of a portion B in fig. 2.

Reference numerals: 1. a frame; 2. a table assembly; 3. a centrifuge assembly; 4. a vibration storage component; 5. a gas adding assembly; 6. a control module; 7. a work table; 8. a communication connector; 9. a centrifugal bin; 10. a sliding plate; 11. a linear module; 12. a centrifuge; 13. a first test tube mounting rack; 14. a centrifugal heating element; 15. a heat insulation plate; 16. a vibration bin; 17. a first oscillating seat; 18. a cylinder; 19. a rotating frame; 20. a rotating member; 21. a second test tube mounting rack; 22. a second rotating seat; 23. a cover plate; 24. a constant temperature bin; 25. a constant temperature heating member; 26. a test tube mounting rack III; 27. a gas adding bin; 28. aerating a heating element; 29. a test tube mounting rack IV; 30. a gas tank; 31. an air adding pipe; 32. a first connecting line; 33. and a second connecting line.

Detailed Description

Example one

The invention provides a preparation method of modified nano calcium carbonate, which comprises the following steps:

s1, mixing quicklime and water in proportion, adding a chelating agent, reacting to obtain lime slurry, vibrating the lime slurry, and adjusting the solid particle content of the lime slurry to 10%;

s2, preparing a modifier; preparing vinyl triethoxysilane, phosphate and deionized water according to the ratio of 6:1:3 to form an ionic surfactant;

s3, adding the ionic surfactant prepared in the S2 into the lime slurry prepared in the S1, and shaking the mixed solution;

s4, standing the mixed solution after the shaking of S3 is finished, adding carbon dioxide into the solution after the standing is finished, and gasifying the solution to prepare a nano calcium carbonate suspension;

s5, drying the nano calcium carbonate suspension, grinding and filtering the dried particles, and drying in vacuum to obtain the nano calcium carbonate.

Example two

The invention provides a preparation method of modified nano calcium carbonate, which comprises the following steps:

s1, mixing quicklime and water in proportion, adding a chelating agent, reacting to obtain lime slurry, vibrating the lime slurry, and adjusting the solid particle content of the lime slurry to 12%;

s2, preparing a modifier; preparing vinyl triethoxysilane, phosphate and deionized water according to a ratio of 4:3:3 to form an ionic surfactant;

s3, adding the ionic surfactant prepared in the S2 into the lime slurry prepared in the S1, and shaking the mixed solution;

s4, standing the mixed solution after the shaking of S3 is finished, adding carbon dioxide into the solution after the standing is finished, and gasifying the solution to prepare a nano calcium carbonate suspension;

s5, drying the nano calcium carbonate suspension, grinding and filtering the dried particles, and drying in vacuum to obtain the nano calcium carbonate.

EXAMPLE III

The invention provides a preparation method of modified nano calcium carbonate, which comprises the following steps:

s1, mixing quicklime and water in proportion, adding a chelating agent, reacting to obtain lime slurry, vibrating the lime slurry, and adjusting the solid particle content of the lime slurry to 15%;

s2, preparing a modifier; preparing vinyl triethoxysilane, phosphate and deionized water according to the ratio of 7:2:1 to form an ionic surfactant;

s3, adding the ionic surfactant prepared in the S2 into the lime slurry prepared in the S1, and shaking the mixed solution;

s4, standing the mixed solution after the shaking of S3 is finished, adding carbon dioxide into the solution after the standing is finished, and gasifying the solution to prepare a nano calcium carbonate suspension;

s5, drying the nano calcium carbonate suspension, grinding and filtering the dried particles, and drying in vacuum to obtain the nano calcium carbonate.

Through comparative experiments, it can be seen that in the first to third embodiments, the purity of the modified nano calcium carbonate prepared in the first embodiment reaches 85%, and is higher than that of the modified nano calcium carbonate prepared in the second and third embodiments, which belongs to the best embodiment ratio.

As shown in fig. 1-4, the preparation equipment used for implementing the method comprises a frame 1, a workbench assembly 2, a centrifugal assembly 3, a shaking storage assembly 4, a gas filling assembly 5, a first connecting line 32, a second connecting line 33 and a control module 6; the centrifugal assembly 3, the vibration storage assembly 4 and the gas filling assembly 5 are arranged on the frame 1; the workbench component 2 is arranged on the centrifugal component 3; the oscillation storage component 4 is in communication connection with the workbench component 2 through a first connecting line 32; the gas filling assembly 5 is in communication connection with the workbench assembly 2 through a second connecting line 33.

Further, in the preparation equipment used for realizing the method, the workbench component 2 comprises a workbench 7 and a communication connector 8; the control module 6 is arranged on the workbench 7; the communication connecting piece 8 is arranged on the workbench 7; the first connecting line 32 and the second connecting line 33 are arranged on the communication connector 8. Through setting up workstation subassembly 2, be convenient for carry out integrated control to centrifugal subassembly 2, shock storage assembly 4 and air entrainment subassembly 5 to improve the work efficiency of preparation modified nanometer calcium carbonate.

Further, in the preparation equipment for realizing the method, the centrifugal assembly 3 comprises a centrifugal bin 9, a centrifugal machine 12, a test tube mounting rack I13 and a centrifugal heating element 14; the centrifugal bin 9 is arranged on the frame 1; the centrifuge 12 is arranged on the centrifugal bin 9; the test tube mounting rack I13 is arranged on the centrifuge 12; the centrifugal heating element 14 is arranged on the centrifuge chamber 9, the centrifugal heating element 14 being located below the centrifuge 12. Through setting up centrifuge 12, be convenient for carry out centrifugal oscillation to modified nanometer calcium carbonate turbid liquid. And a centrifugal heating element 14 is arranged, so that the modified nano calcium carbonate suspension in the centrifugal process is ensured to be at the optimal experimental temperature.

Further, in the preparation equipment used for implementing the method, the centrifugal assembly 3 further comprises a sliding plate 10 and a linear module 11; the linear module 11 is arranged on the centrifugal bin 9; the sliding plate 10 is arranged on the linear module 11, and the sliding plate 10 is arranged on the centrifugal bin 9 in a sliding manner; the centrifuge assembly 3 further comprises a heat shield 15; a heat shield 15 is provided at the end of the centrifuge chamber 9 adjacent the table assembly 2.

Further, in the preparation equipment used for realizing the method, the oscillation storage component 4 comprises an oscillation bin 16, an oscillation machine, a cover plate 23, a constant temperature bin 24, a constant temperature heating element 25 and a test tube mounting rack III 26; the oscillation bin 16 is arranged on the frame 1; the cover plate 23 is arranged on the oscillating bin 16 in an oscillating way; the oscillating machine is arranged in the oscillating bin 16; the constant temperature bin 24 is arranged on the frame 1; the third test tube mounting rack 26 is arranged on the constant temperature bin 24; and is positioned at one side of the oscillating machine; the constant temperature heating element 25 is arranged on the constant temperature bin 24 and is positioned below the test tube mounting rack III 26.

Furthermore, in the preparation equipment used for realizing the method, the shaking machine comprises a first rotating seat 17, a cylinder 18, a rotating frame 19, a rotating part 20, a second test tube mounting rack 21 and a second rotating seat 22; the first rotating seat 17 is rotatably arranged on the oscillating bin 16; the cylinder body end of the cylinder 18 is arranged on the first rotating seat 17; the second rotating seat 22 is arranged at the piston end of the cylinder 18; the test tube mounting rack II 21 is arranged on the rotating seat II 22; the rotating frame 19 driven by the rotating piece 20 is rotatably arranged on the second test tube mounting frame 21.

Further, in the preparation equipment for realizing the method, the gas filling assembly 5 comprises a gas filling bin 27, a gas filling heating element 28, a test tube mounting rack IV 29, a gas tank 30 and a gas filling pipe 31; the air adding bin 27 is arranged on the frame 1; the gas-adding heating element 28 is arranged on the gas-adding bin 27; the test tube mounting rack IV 29 is arranged on the gas filling bin 27 and is positioned above the gas filling heating element 28; the air tank 30 is arranged on the air charging bin 27; a gas filling pipe 31 is provided on the gas tank 30.

The operation steps of the device are as follows:

s1, controlling the temperature of the centrifugal heating element 14, the constant-temperature heating element 25 and the air-entraining heating element 28 by using the control module 6;

s2, placing quicklime and water in a test tube according to a proportion, adding a chelating agent into the test tube, placing the test tube on a second test tube mounting rack 21, and reacting to obtain lime slurry; the rotating piece 20 works to drive the test tube and the second quisqualis mounting rack 21 to rotate on the rotating rack 19, so that the lime slurry is vibrated, and the solid particle content of the lime slurry is adjusted to 10% -15%;

s3, preparing a modifier; adding vinyl triethoxysilane, phosphate and deionized water into a test tube according to the proportion of 6:1:3 for preparation to form an ionic surfactant;

s4, adding the ionic surfactant prepared in the S3 into the lime slurry prepared in the S1, and placing the mixed solution on a centrifuge 12 for shaking centrifugation to obtain a mixed solution;

s5, placing the test tube in the constant temperature bin 24, standing the mixed solution after the shaking of S4, placing the test tube on a test tube mounting rack IV 29 after the standing is finished, adding carbon dioxide into the solution, and gasifying the solution to prepare the nano calcium carbonate suspension;

s6, drying the nano calcium carbonate suspension, grinding and filtering the dried particles, and drying in vacuum to obtain the nano calcium carbonate.

It is to be understood that the above-described embodiments of the present invention are merely illustrative of or explaining the principles of the invention and are not to be construed as limiting the invention. Therefore, any modification, equivalent replacement, improvement and the like made without departing from the spirit and scope of the present invention should be included in the protection scope of the present invention. Further, it is intended that the appended claims cover all such variations and modifications as fall within the scope and boundaries of the appended claims or the equivalents of such scope and boundaries.