Preparation method of cubic porous calcium carbonate with high specific surface area

Abstract

The invention belongs to the technical field of functional calcium carbonate preparation, and particularly relates to a preparation method of high-specific-surface-area cubic porous calcium carbonate. The method comprises the following steps: S1, heating a calcium chloride solution, and adding calcium hydroxide to obtain a calcium chloride treatment solution; s2, adding a surface modifier into the sodium carbonate solution to obtain a sodium carbonate treatment solution; s3, adding the sodium carbonate treatment solution into the calcium chloride treatment solution to obtain a mixed solution; s4, performing ultrasonic crushing treatment on the mixed solution, then performing centrifugal treatment, and performing drip washing to obtain the cubic porous calcium carbonate with the high specific surface area. According to the method provided by the invention, the calcium hydroxide is introduced into the calcium chloride solution, the calcium hydroxide and the calcium chloride grab the sodium carbonate, the calcium hydroxide and the sodium carbonate react to generate the sodium hydroxide, and the sodium hydroxide and the calcium chloride are combined to generate the calcium hydroxide; the preparation of porous calcium carbonate of cubic calcium carbonate is realized.

Description

Technical Field

[0001] The invention belongs to the technical field of functional calcium carbonate preparation, and in particular relates to a method for preparing cubic porous calcium carbonate with a high specific surface area. Background Art

[0002] In the traditional calcium carbonate production process, the specific surface area of ​​the obtained calcium carbonate product is relatively small, usually 1-10m 2 / g range. This kind of calcium carbonate with low specific surface area has certain limitations in certain application fields. For example, in the rubber and plastics industry, calcium carbonate with low specific surface area has poor compatibility with organic matrices and is difficult to disperse evenly, resulting in unsatisfactory mechanical properties of the filled material; in the catalyst field, the smaller specific surface area limits the exposure of the active sites of the catalyst, thereby affecting the efficiency of the catalytic reaction. In order to meet the market demand for high-performance materials, researchers have been working hard to explore methods to increase the specific surface area of ​​calcium carbonate. At present, the preparation methods of porous calcium carbonate mostly adopt template method, emulsion liquid film method, co-precipitation method, solvent-hydrothermal method, gel crystallization method, etc., and porous calcium carbonate particles with different morphologies can be obtained by different preparation methods. However, most of these methods have complex processes and harsh reaction conditions, and are difficult to be applied on a large scale in industry.

[0003] In summary, although the existing methods for preparing high specific surface area calcium carbonate have achieved some results to a certain extent, there are still many problems, such as high production cost, complex process, unstable product quality, environmental pollution, etc. Therefore, developing a simple and easy method for preparing high specific surface area calcium carbonate has important practical significance and application value. Summary of the invention

[0004] The main purpose of the present invention is to provide a method for preparing cubic porous calcium carbonate with high specific surface area to overcome the shortcomings of the prior art.

[0005] In order to achieve the above-mentioned invention object, the technical solution adopted by the present invention includes:

[0006] According to one aspect of an embodiment of the present invention, there is provided a method for preparing a high specific surface area cubic porous calcium carbonate, comprising the following steps:

[0007] S1, after heating the calcium chloride solution, adding calcium hydroxide to make the pH value of the calcium chloride solution greater than 12, to obtain a calcium chloride treatment solution;

[0008] S2, adding a surface modifier to a sodium carbonate solution to obtain a sodium carbonate treatment solution;

[0009] S3, adding the sodium carbonate treatment solution to the calcium chloride treatment solution while stirring to obtain a mixed solution;

[0010] S4, subjecting the mixed solution to ultrasonic crushing treatment and then to centrifugation treatment, collecting the precipitate, and rinsing the precipitate to obtain the high specific surface area cubic porous calcium carbonate.

[0011] Furthermore, in step S1, the calcium chloride solution is heated to 30-50°C.

[0012] Furthermore, in step S1, the concentration of the calcium chloride solution is 300-400 g / L.

[0013] Furthermore, in step S1, the concentration of calcium hydroxide in the calcium chloride treatment solution is 0.1-0.15 g / L.

[0014] Furthermore, in step S1, ferric chloride is added to the calcium chloride solution so that the concentration of ferric chloride in the calcium chloride treatment solution is 0.5-1.0 g / L.

[0015] Furthermore, in step S2, the sodium carbonate solution is first heated to 30-50° C., and then the surface modifier is added.

[0016] Furthermore, in step S2, the sodium carbonate concentration in the sodium carbonate treatment solution is 300-400 g / L.

[0017] Furthermore, in step S2, the surface modifier includes CTAB or SDBS, and the concentration of the surface modifier is 1-10 g / L.

[0018] Furthermore, in step S3, the stirring is carried out in a mixer, and the rotation speed of the mixer is 60-120 r / min. During the stirring, when the torque reaches 400-500 Nm, the rotation speed is reduced to 10-20 r / min; when the torque is reduced to 20-50 Nm, the rotation speed is increased to 60-80 r / min.

[0019] Furthermore, the mixed liquid is treated in an ultrasonic crushing tank for 30-60 minutes.

[0020] Compared with the prior art, the advantages of the present invention include:

[0021] The present invention provides a method for preparing a high specific surface area cubic porous calcium carbonate, wherein calcium hydroxide is introduced into a calcium chloride solution, calcium hydroxide and calcium chloride rob sodium carbonate, calcium hydroxide and sodium carbonate react to generate sodium hydroxide, sodium hydroxide and calcium chloride combine to generate calcium hydroxide, and multiple reactions and conversions are performed on the surface of calcium carbonate crystals to achieve the preparation of a cubic porous calcium carbonate. The entire process of the present invention is simple, does not require special equipment, and is convenient for large-scale production. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present invention. Moreover, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0023] Figure 1 This is a process flow chart of preparing cubic porous calcium carbonate with high specific surface area in a typical embodiment of the present invention;

[0024] Figure 2 This is a SEM image of porous calcium carbonate prepared in a typical embodiment of the present invention;

[0025] Figure 3 for Figure 2 A partial enlarged view of . DETAILED DESCRIPTION

[0026] In view of the deficiencies in the prior art, the inventor of this case has proposed the technical solution of the present invention after long-term research and extensive practice. The technical solution, its implementation process and principle will be further explained as follows.

[0027] The present invention is further described in detail below in conjunction with specific embodiments, and the examples provided are only for illustrating the present invention, rather than for limiting the scope of the present invention. The examples provided below can be used as a guide for further improvements by those of ordinary skill in the art, and do not constitute a limitation of the present invention in any way.

[0028] The experimental methods in the following examples, unless otherwise specified, are all conventional methods, and are performed according to the techniques or conditions described in the literature in the field or according to the product instructions. The materials, reagents, etc. used in the following examples, unless otherwise specified, can all be obtained from commercial channels.

[0029] like Figure 1 As shown, an embodiment of the present invention provides a method for preparing a high specific surface area cubic porous calcium carbonate, comprising the following steps:

[0030] S1. A calcium chloride solution having a concentration of 300-400 g / L is heated to 30-50° C., and then calcium hydroxide is added to make the pH value of the calcium chloride solution greater than 12 to obtain a calcium chloride treatment solution; the concentration of calcium hydroxide in the calcium chloride treatment solution is 0.1-0.15 g / L; and ferric chloride is further added to the calcium chloride solution, so that the concentration of ferric chloride in the calcium chloride treatment solution is 0.5-1.0 g / L;

[0031] S2, heating the sodium carbonate solution to 30-50° C., and then adding a surface modifier to obtain a sodium carbonate treatment solution; the sodium carbonate concentration in the sodium carbonate treatment solution is 300-400 g / L; the surface modifier includes CTAB or SDBS, and the concentration of the surface modifier is 1-10 g / L;

[0032] S3, stirring while adding the sodium carbonate treatment solution to the calcium chloride treatment solution to obtain a mixed solution; the stirring is carried out in a stirrer, the rotating speed of the stirrer is 60-120r / min, during the stirring, when the torque reaches 400-500 Nm, the rotating speed is reduced to 10-20r / min; when the torque is reduced to 20-50 Nm, the rotating speed is increased to 60-80r / min, and stirring is continued for 30-60min;

[0033] S4, sending the mixed solution into an ultrasonic crushing tank for treatment, the treatment time is 30-60min; then centrifuging, collecting the precipitate, and eluting the precipitate to obtain the high specific surface area cubic porous calcium carbonate.

[0034] Example 1

[0035] This embodiment provides a method for preparing a high specific surface area cubic porous calcium carbonate, comprising the following steps:

[0036] S1, heating a 300 g / L calcium chloride solution to 30° C., then adding calcium hydroxide to make the pH value of the calcium chloride solution greater than 12, to obtain a calcium chloride treatment solution; the concentration of calcium hydroxide in the calcium chloride treatment solution is 0.1 g / L; ferric chloride is further added to the calcium chloride solution, so that the concentration of ferric chloride in the calcium chloride treatment solution is 0.5 g / L;

[0037] S2, heating the sodium carbonate solution to 30° C., and then adding a surface modifier to obtain a sodium carbonate treatment solution; the sodium carbonate concentration in the sodium carbonate treatment solution is 300 g / L; the surface modifier includes CTAB or SDBS, and the concentration of the surface modifier is 1 g / L;

[0038] S3, stirring while adding the sodium carbonate treatment solution to the calcium chloride treatment solution to obtain a mixed solution; the stirring is carried out in a stirrer, the rotating speed of the stirrer is 60r / min, and during the stirring, when the torque reaches 400 Nm, the speed is reduced to 10r / min; when the torque is reduced to 20 Nm, the speed is increased to 60r / min, and stirring is continued for 30min;

[0039] S4, sending the mixed solution into an ultrasonic crushing tank for treatment, the treatment time is 30 minutes; then centrifuging, collecting the precipitate, and eluting the precipitate to obtain the high specific surface area cubic porous calcium carbonate.

[0040] Example 2

[0041] This embodiment provides a method for preparing a high specific surface area cubic porous calcium carbonate, comprising the following steps:

[0042] S1. A calcium chloride solution having a concentration of 350 g / L is heated to 40° C., and then calcium hydroxide is added to make the pH value of the calcium chloride solution greater than 12 to obtain a calcium chloride treatment solution; the concentration of calcium hydroxide in the calcium chloride treatment solution is 0.125 g / L; ferric chloride is further added to the calcium chloride solution, so that the concentration of ferric chloride in the calcium chloride treatment solution is 0.75 g / L;

[0043] S2, heating the sodium carbonate solution to 40° C., and then adding a surface modifier to obtain a sodium carbonate treatment solution; the sodium carbonate concentration in the sodium carbonate treatment solution is 350 g / L; the surface modifier includes CTAB or SDBS, and the concentration of the surface modifier is 5.5 g / L;

[0044] S3, stirring while adding the sodium carbonate treatment solution to the calcium chloride treatment solution to obtain a mixed solution; the stirring is carried out in a stirrer, the rotating speed of the stirrer is 90r / min, and during the stirring, when the torque reaches 450 Nm, the speed is reduced to 15r / min; when the torque is reduced to 35 Nm, the speed is increased to 70r / min, and stirring is continued for 45min;

[0045] S4, sending the mixed solution into an ultrasonic crushing tank for treatment, the treatment time is 45min; then centrifuging, collecting the precipitate, and eluting the precipitate to obtain the high specific surface area cubic porous calcium carbonate.

[0046] Example 3

[0047] This embodiment provides a method for preparing a high specific surface area cubic porous calcium carbonate, comprising the following steps:

[0048] S1. A calcium chloride solution having a concentration of 300-400 g / L is heated to 50° C., and then calcium hydroxide is added to make the pH value of the calcium chloride solution greater than 12 to obtain a calcium chloride treatment solution; the concentration of calcium hydroxide in the calcium chloride treatment solution is 0.15 g / L; and ferric chloride is further added to the calcium chloride solution, so that the concentration of ferric chloride in the calcium chloride treatment solution is 1.0 g / L;

[0049] S2, heating the sodium carbonate solution to 50° C., and then adding a surface modifier to obtain a sodium carbonate treatment solution; the sodium carbonate concentration in the sodium carbonate treatment solution is 400 g / L; the surface modifier includes CTAB or SDBS, and the concentration of the surface modifier is 10 g / L;

[0050] S3, stirring while adding the sodium carbonate treatment solution to the calcium chloride treatment solution to obtain a mixed solution; the stirring is carried out in a stirrer, the rotating speed of the stirrer is 120r / min, and during the stirring, when the torsion reaches 500 Nm, the rotating speed is reduced to 20r / min; when the torsion is reduced to 50 Nm, the rotating speed is increased to 80r / min, and stirring is continued for 60min;

[0051] S4, sending the mixed solution into an ultrasonic crushing tank for treatment, the treatment time is 60min; then centrifuging, collecting the precipitate, and eluting the precipitate to obtain the high specific surface area cubic porous calcium carbonate.

[0052] like Figure 2 As shown, the calcium carbonate prepared by the method of the present invention has a cubic structure and a very uniform particle size distribution of about 0.5 microns, excellent physical and chemical properties, and has a relatively direct improvement in reducing the friction coefficient during the application process. Figure 3 for Figure 2 A local enlarged schematic diagram of Figure 3 As shown, the calcium carbonate prepared by the method of the present invention has a porous structure. Due to this structure, its specific surface area is much larger than that of conventional light calcium carbonate.

[0053] Experiment 1

[0054] Samples 1 and 2 were prepared by the method of the present invention. Sample 1 in this experiment was prepared by using calcium chloride purchased online to form a solution, and then the method of the present invention was used to generate porous calcium carbonate with a high specific surface area; Sample 2 was a calcium chloride solution prepared by reacting papermaking white mud and industrial by-product hydrochloric acid, and then the method of the present invention was used to generate porous calcium carbonate with a high specific surface area.

[0055] The specific surface areas of Samples 1 and 2 are compared with those of commercially available products, as shown in Table 1 below;

[0056] Table 1

[0057] sample Specific surface area 1 <![CDATA[25.22m 2 / g]]> 2 <![CDATA[27.49m 2 / g]]> Light calcium carbonate sold on the market <![CDATA[5.16m 2 / g]]>

[0058] As can be seen from Table 1, by adopting the method of the present invention, a product with a high specific surface area is obtained; and the high specific surface area porous calcium carbonate prepared by the calcium chloride solution prepared from two industrial hazardous wastes (industrial by-product hydrochloric acid and papermaking white mud) through the above reaction has similar performance indicators to the high specific surface area porous calcium carbonate prepared from commercially available calcium chloride. Therefore, the two industrial hazardous wastes can be transformed into resources, reducing costs and increasing efficiency while safeguarding environmental protection.

[0059] The above are only some embodiments of the present invention. It should be pointed out that for ordinary technicians in this field, other modifications and improvements can be made without departing from the creative concept of the present invention, which all belong to the protection scope of the present invention.

Claims

1. A method for preparing high specific surface area cubic porous calcium carbonate, characterized in that: The following steps are involved: S1, after heating the calcium chloride solution, adding calcium hydroxide to make the pH value of the calcium chloride solution greater than 12, to obtain a calcium chloride treatment solution; S2, adding a surface modifier to a sodium carbonate solution to obtain a sodium carbonate treatment solution; S3, adding the sodium carbonate treatment solution to the calcium chloride treatment solution while stirring to obtain a mixed solution; S4, subjecting the mixed solution to ultrasonic crushing treatment and then to centrifugation treatment, collecting the precipitate, and rinsing the precipitate to obtain the high specific surface area cubic porous calcium carbonate.

2. The method for preparing the high specific surface area cubic porous calcium carbonate according to claim 1, characterized in that: In step S1, the calcium chloride solution is heated to 30-50°C.

3. The method for preparing the high specific surface area cubic porous calcium carbonate according to claim 1, characterized in that: In step S1, the concentration of the calcium chloride solution is 300-400 g / L.

4. The method for preparing the high specific surface area cubic porous calcium carbonate according to claim 1, characterized in that: In step S1, the concentration of calcium hydroxide in the calcium chloride treatment solution is 0.1-0.15 g / L.

5. The method for preparing the high specific surface area cubic porous calcium carbonate according to claim 1, characterized in that: In step S1, ferric chloride is added to the calcium chloride solution so that the concentration of ferric chloride in the calcium chloride treatment solution is 0.5-1.0 g / L.

6. The method for preparing the high specific surface area cubic porous calcium carbonate according to claim 1, characterized in that: In step S2, the sodium carbonate solution is first heated to 30-50° C., and then the surface modifier is added.

7. The method for preparing the high specific surface area cubic porous calcium carbonate according to claim 1, characterized in that: In step S2, the sodium carbonate concentration in the sodium carbonate treatment solution is 300-400 g / L.

8. The method for preparing the high specific surface area cubic porous calcium carbonate according to claim 1, characterized in that: In step S2, the surface modifier includes CTAB or SDBS, and the concentration of the surface modifier is 1-10 g / L.

9. The method for preparing the high specific surface area cubic porous calcium carbonate according to claim 1, characterized in that: In step S3, the stirring is carried out in a mixer, and the rotation speed of the mixer is 60-120 r / min. During the stirring, when the torque reaches 400-500 Nm, the rotation speed is reduced to 10-20 r / min; when the torque is reduced to 20-50 Nm, the rotation speed is increased to 60-80 r / min.

10. The method for preparing the high specific surface area cubic porous calcium carbonate according to claim 1, characterized in that: The mixed liquid is treated in an ultrasonic crushing tank for 30-60 minutes.

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