CN115974126A - Method for regulating and controlling crystal morphology of phosphogypsum-based calcium sulfate dihydrate - Google Patents
Method for regulating and controlling crystal morphology of phosphogypsum-based calcium sulfate dihydrate Download PDFInfo
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- CN115974126A CN115974126A CN202211621346.4A CN202211621346A CN115974126A CN 115974126 A CN115974126 A CN 115974126A CN 202211621346 A CN202211621346 A CN 202211621346A CN 115974126 A CN115974126 A CN 115974126A
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- phosphogypsum
- calcium sulfate
- sulfate dihydrate
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- stirring
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- PASHVRUKOFIRIK-UHFFFAOYSA-L calcium sulfate dihydrate Chemical compound O.O.[Ca+2].[O-]S([O-])(=O)=O PASHVRUKOFIRIK-UHFFFAOYSA-L 0.000 title claims abstract description 141
- 239000013078 crystal Substances 0.000 title claims abstract description 37
- 230000001105 regulatory effect Effects 0.000 title claims abstract description 25
- 238000000034 method Methods 0.000 title claims abstract description 24
- 230000001276 controlling effect Effects 0.000 title claims abstract description 20
- 230000033228 biological regulation Effects 0.000 claims abstract description 10
- 239000012296 anti-solvent Substances 0.000 claims abstract description 5
- 238000003756 stirring Methods 0.000 claims description 32
- 238000010438 heat treatment Methods 0.000 claims description 24
- 238000001035 drying Methods 0.000 claims description 22
- 239000000047 product Substances 0.000 claims description 15
- 239000012065 filter cake Substances 0.000 claims description 14
- 238000001914 filtration Methods 0.000 claims description 14
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 11
- 239000000126 substance Substances 0.000 claims description 9
- 239000007788 liquid Substances 0.000 claims description 8
- 238000002360 preparation method Methods 0.000 claims description 8
- 239000008367 deionised water Substances 0.000 claims description 7
- 229910021641 deionized water Inorganic materials 0.000 claims description 7
- DNIAPMSPPWPWGF-GSVOUGTGSA-N (R)-(-)-Propylene glycol Chemical compound C[C@@H](O)CO DNIAPMSPPWPWGF-GSVOUGTGSA-N 0.000 claims description 5
- 239000002904 solvent Substances 0.000 claims description 3
- 239000002994 raw material Substances 0.000 claims description 2
- 229960001714 calcium phosphate Drugs 0.000 claims 1
- 229910000389 calcium phosphate Inorganic materials 0.000 claims 1
- 239000001506 calcium phosphate Substances 0.000 claims 1
- 239000002131 composite material Substances 0.000 claims 1
- 150000002191 fatty alcohols Chemical class 0.000 claims 1
- 238000002156 mixing Methods 0.000 claims 1
- KFZMGEQAYNKOFK-UHFFFAOYSA-N Isopropanol Chemical compound CC(C)O KFZMGEQAYNKOFK-UHFFFAOYSA-N 0.000 description 6
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 6
- BDERNNFJNOPAEC-UHFFFAOYSA-N propan-1-ol Chemical compound CCCO BDERNNFJNOPAEC-UHFFFAOYSA-N 0.000 description 6
- 238000007873 sieving Methods 0.000 description 6
- 239000012467 final product Substances 0.000 description 5
- 239000000843 powder Substances 0.000 description 5
- 238000001179 sorption measurement Methods 0.000 description 5
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 4
- 230000000694 effects Effects 0.000 description 2
- 239000002689 soil Substances 0.000 description 2
- 208000001889 Acid-Base Imbalance Diseases 0.000 description 1
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000004566 building material Substances 0.000 description 1
- 239000013064 chemical raw material Substances 0.000 description 1
- 238000002425 crystallisation Methods 0.000 description 1
- 230000008025 crystallization Effects 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000011049 filling Methods 0.000 description 1
- 239000000706 filtrate Substances 0.000 description 1
- 239000004615 ingredient Substances 0.000 description 1
- 229910021645 metal ion Inorganic materials 0.000 description 1
- 230000020477 pH reduction Effects 0.000 description 1
- 239000012466 permeate Substances 0.000 description 1
- 239000011574 phosphorus Substances 0.000 description 1
- 229910052698 phosphorus Inorganic materials 0.000 description 1
- 229920000642 polymer Polymers 0.000 description 1
- -1 roadbeds Substances 0.000 description 1
- 239000002910 solid waste Substances 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
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Classifications
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W30/00—Technologies for solid waste management
- Y02W30/50—Reuse, recycling or recovery technologies
- Y02W30/91—Use of waste materials as fillers for mortars or concrete
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- Solid-Sorbent Or Filter-Aiding Compositions (AREA)
Abstract
The invention discloses a method for regulating and controlling the morphology of phosphogypsum-based calcium sulfate dihydrate crystals, which realizes the regulation and control of the morphology of the phosphogypsum-based calcium sulfate dihydrate crystals by regulating the types of anti-solvents and the reaction temperature, improves the added value of products, has obvious economic benefit and widens the use path of phosphogypsum.
Description
Technical Field
The invention relates to a method for regulating and controlling the crystal morphology of phosphogypsum-based calcium sulfate dihydrate, belonging to the technical field of chemical raw material preparation.
Background
The phosphorus chemical industry is one of the national pillar industries, and produces solid waste phosphogypsum while bringing economic benefit, because the yield of the phosphogypsum is huge and the comprehensive utilization rate is low, the phosphogypsum is mainly stockpiled, and the stockpiling of the phosphogypsum not only occupies a large amount of land and wastes a large amount of economy, but also causes a series of environmental problems, so that the acid-base imbalance of the soil around the yard pollutes the farmland around the yard; the filtrate permeates into the underground water, so that the pollution of water resources is caused; because the output is huge, the dam of the storage yard is higher, so that the danger of dam break at any time exists, and the life safety of surrounding residents is threatened; currently, phosphogypsum is applied to the aspects of building materials, roadbeds, soil conditioners, chemical raw materials, polymer filling and the like, and the structure of the phosphogypsum is an important factor influencing the application of the phosphogypsum. Therefore, the phosphogypsum structure is regulated and controlled, and the additional value of the phosphogypsum structure is improved, so that the phosphogypsum resource utilization is of very important practical significance.
In phosphogypsum structure regulation, the structure of calcium sulfate dihydrate is usually regulated by using an atmospheric pressure acidification method, and a crystal form regulator (a crystallization promoter) is used for changing the crystal growth mode. Therefore, an anti-solvent method is provided for regulating and controlling the structure of the phosphogypsum, and the shape of the calcium sulfate dihydrate in the phosphogypsum is regulated and controlled by regulating the type of the anti-solvent and the reaction temperature.
Disclosure of Invention
The invention provides a novel method for adjusting phosphogypsum-based calcium sulfate dihydrate, prepares various phosphogypsum crystals with controllable shapes, solves the problem that the application field of the phosphogypsum is limited due to the shape of the phosphogypsum in the prior art, expands the application field of the phosphogypsum, and has the advantages of simple operation, environment-friendly solvent and obvious effect.
The technical scheme of the invention is as follows: a method for regulating and controlling crystal morphology of phosphogypsum-based calcium sulfate dihydrate comprises the following steps:
(1) Preparation of phosphogypsum solution: drying the phosphogypsum at 60 ℃, crushing the phosphogypsum, and sieving the crushed phosphogypsum with a 100-mesh sieve according to a solid-to-liquid ratio of 1: 100-500 dissolving the phosphogypsum in deionized water, stirring for a certain time at room temperature, and filtering out insoluble substances to obtain the phosphogypsum solution.
(2) And (3) regulation and control of the structure: putting a certain amount of phosphogypsum solution into a stirring and heating device, heating at the temperature of 1-75 ℃, stirring at the speed of 100-500 r/min, then adding aliphatic alcohol with the same temperature into the phosphogypsum solution, adding the aliphatic alcohol into the phosphogypsum solution by 20-100 percent, stirring and heating for 3-10 min, and filtering while the solution is hot to obtain a filter cake.
(3) And (3) drying: drying the obtained filter cake at 50-80 deg.c for 2-8 hr to obtain the product.
The invention has the beneficial effects that:
the method has the advantages of simple operation, environment-friendly solvent, obvious effect and larger specific surface area, and the obtained phosphogypsum-based calcium sulfate dihydrate crystal has good adsorption performance on metal ions in water.
Drawings
FIG. 1 is a flow chart of regulation;
FIG. 2 shows the morphology of a methanol 55 ℃ product;
FIG. 3 is a plot of ethanol 55 deg.C product;
FIG. 4 shows the morphology of n-propanol product at 55 ℃;
FIG. 5 shows the morphology of a 55 ℃ isopropanol product;
FIG. 6 shows the morphology of the isopropanol 15 ℃.
Figure 7 shows the specific surface area and adsorption performance of phosphogypsum-based calcium sulphate dihydrate crystals prepared by different anti-solvents.
Detailed Description
Example 1
A method for regulating and controlling the crystal morphology of phosphogypsum-based calcium sulfate dihydrate comprises the following steps:
(1) Preparation of phosphogypsum solution: drying the phosphogypsum at 60 ℃, crushing the phosphogypsum, and sieving the crushed phosphogypsum by a 100-mesh sieve according to a solid-liquid ratio of 1:200 dissolving the phosphogypsum in deionized water, stirring for 4hr at room temperature, and filtering out insoluble substances to obtain the phosphogypsum solution.
(2) And (3) regulation and control of the structure: putting a certain amount of phosphogypsum solution into a stirring and heating device, heating at 55 ℃, stirring at the speed of 200r/min, then adding methanol with the same temperature into the phosphogypsum solution, adding 30 percent of the phosphogypsum solution, stirring and heating for 5min, and filtering while hot to obtain a filter cake.
(3) And (3) drying: drying the obtained filter cake at 60 deg.C for 4hr to obtain the final product.
The obtained product is white powder, the microscopic morphology is butterfly-shaped sheet crystal, the length of the crystal is 30-100 mu m, the width is 20-30 mu m, and the thickness is 1-10 mu m; the ingredient is calcium sulfate dihydrate, and the whiteness is 90.60%. See figure 2
(4) The specific surface area and the adsorption performance of the obtained phosphogypsum-based calcium sulfate dihydrate crystal are shown in a figure 7.
Example 2
A method for regulating and controlling the crystal morphology of phosphogypsum-based calcium sulfate dihydrate comprises the following steps:
(1) Preparation of phosphogypsum solution: drying the phosphogypsum at 60 ℃, crushing the phosphogypsum, and sieving the crushed phosphogypsum by a 100-mesh sieve according to a solid-liquid ratio of 1:200 dissolving the phosphogypsum in deionized water, stirring for 4hr at room temperature, and filtering out insoluble substances to obtain the phosphogypsum solution.
(2) And (3) regulation and control of the structure: putting a certain amount of phosphogypsum solution in a stirring and heating device, heating at 55 ℃, stirring at the speed of 200r/min, then adding ethanol with the same temperature into the phosphogypsum solution, adding 30 percent of the phosphogypsum solution, stirring and heating for 5min, and filtering while hot to obtain a filter cake.
(3) And (3) drying: drying the obtained filter cake at 60 deg.C for 4hr to obtain the final product.
The obtained product is white powder, the microscopic morphology is coexistence of butterfly-shaped sheet crystals and columnar crystals, the length of the white butterfly-shaped sheet crystals is 30-150 mu m, the width is 20-30 mu m, and the thickness is 1-10 mu m; the length of the columnar crystal is 30-150 mu m, and the diameter is 3-mu m; the product component is calcium sulfate dihydrate, and the whiteness is 91.86%.
(4) The specific surface area and the adsorption performance of the obtained phosphogypsum-based calcium sulfate dihydrate crystal are shown in a figure 7.
Example 3
A method for regulating and controlling the crystal morphology of phosphogypsum-based calcium sulfate dihydrate comprises the following steps:
(1) Preparation of phosphogypsum solution: drying the phosphogypsum at 60 ℃, crushing the phosphogypsum, and sieving the crushed phosphogypsum by a 100-mesh sieve according to a solid-liquid ratio of 1:200 dissolving the phosphogypsum in deionized water, stirring for 4hr at room temperature, and filtering out insoluble substances to obtain the phosphogypsum solution.
(2) And (3) regulation and control of the structure: putting a certain amount of phosphogypsum solution into a stirring and heating device, heating at 55 ℃, stirring at the speed of 200r/min, then adding n-propanol with the same temperature into the phosphogypsum solution, adding 30% of the phosphogypsum solution, stirring and heating for 5min, and filtering while hot to obtain a filter cake.
(3) And (3) drying: drying the obtained filter cake at 60 deg.C for 4hr to obtain the final product.
The obtained product is white powder, the micro appearance is hexagonal prism-shaped crystal, the length is 5-50 mu m, and the diameter is 1-2 mu m; the product component is calcium sulfate dihydrate, and the whiteness is 96.26%.
Example 4
A method for regulating and controlling the crystal morphology of phosphogypsum-based calcium sulfate dihydrate comprises the following steps:
(1) Preparation of phosphogypsum solution: drying the phosphogypsum at 60 ℃, crushing the phosphogypsum, and sieving the crushed phosphogypsum by a 100-mesh sieve according to a solid-liquid ratio of 1:200 dissolving the phosphogypsum in deionized water, stirring for 4hr at room temperature, and filtering out insoluble substances to obtain the phosphogypsum solution.
(2) And (3) regulation and control of the structure: putting a certain amount of phosphogypsum solution into a stirring and heating device, heating at 55 ℃, stirring at the speed of 200r/min, then adding isopropanol at the same temperature into the phosphogypsum solution, adding 30 percent of the phosphogypsum solution, stirring and heating for 5min, and filtering while hot to obtain a filter cake.
(3) And (3) drying: drying the obtained filter cake at 60 deg.C for 4hr to obtain the final product.
The obtained product is white powder, the micro appearance is hexagonal prism-shaped crystal, the length is 10-70 μm, and the diameter is 1-2 μm; the product component is calcium sulfate dihydrate, and the whiteness is 95.93%.
(4) The specific surface area and the adsorption performance of the obtained phosphogypsum-based calcium sulfate dihydrate crystal are shown in a figure 7.
Example 5
A method for regulating and controlling the crystal morphology of phosphogypsum-based calcium sulfate dihydrate comprises the following steps:
(1) Preparation of phosphogypsum solution: drying the phosphogypsum at 60 ℃, crushing the phosphogypsum, and sieving the crushed phosphogypsum with a 100-mesh sieve according to a solid-to-liquid ratio of 1:200 dissolving the phosphogypsum in deionized water, stirring for 4hr at room temperature, and filtering out insoluble substances to obtain the phosphogypsum solution.
(2) And (3) regulation and control of the structure: putting a certain amount of phosphogypsum solution into a stirring and heating device, heating at 15 ℃, stirring at the speed of 200r/min, adding n-propanol with the same temperature into the phosphogypsum solution, adding 30% of the phosphogypsum solution, stirring and heating for 5min, and filtering to obtain a filter cake.
(3) And (3) drying: drying the obtained filter cake at 60 deg.C for 4hr to obtain the final product.
The obtained product is white powder, the microscopic appearance is hexagonal prism-shaped crystal, the length is 1-5 mu m, and the diameter is 0.1-0.3 mu m; the product component is calcium sulfate dihydrate, and the whiteness is 95.74%.
Claims (9)
1. A method for regulating and controlling a crystal structure of phosphogypsum-based calcium sulfate dihydrate is characterized by comprising the following steps: mixing, stirring and heating phosphogypsum serving as a calcium sulfate dihydrate source, water serving as a phosphogypsum solvent and aliphatic alcohol serving as an anti-solvent to obtain the phosphogypsum-calcium-phosphate composite material.
2. The method for regulating and controlling the crystal morphology of phosphogypsum-based calcium sulfate dihydrate according to claim 1, which is characterized in that: the method comprises the following steps:
(1) Preparation of phosphogypsum solution: drying the phosphogypsum according to the solid-liquid ratio of 1: dissolving 100-500 parts of the raw materials in deionized water, stirring at room temperature, and filtering insoluble substances to obtain a phosphogypsum solution;
(2) And (3) regulation and control of the structure: placing the phosphogypsum solution in a stirring and heating device, heating at the temperature of 1-75 ℃, stirring at the speed of 100-500 r/min, adding aliphatic alcohol with the same temperature into the phosphogypsum solution, adding the aliphatic alcohol into the phosphogypsum solution by 20-100 percent, stirring and heating for 3-10 min, and filtering while hot to obtain a filter cake;
(3) And (3) drying: and drying the obtained filter cake at 50-80 ℃ for 2-8 h to obtain the product.
3. The method for regulating and controlling the crystal morphology of phosphogypsum-based calcium sulfate dihydrate according to claim 2, which is characterized in that: in the step (1), the solid-liquid ratio is 1:200.
4. the method for regulating and controlling the crystal morphology of phosphogypsum-based calcium sulfate dihydrate according to claim 2, which is characterized in that: in the step (1), the stirring time at room temperature is 4h.
5. The method for regulating and controlling the crystal morphology of phosphogypsum-based calcium sulfate dihydrate according to claim 2, characterized in that: in the step (2), the heating temperature is 55 ℃.
6. The method for regulating and controlling the crystal morphology of phosphogypsum-based calcium sulfate dihydrate according to claim 2, which is characterized in that: in the step (2), the stirring speed is 200r/min.
7. The method for regulating and controlling the crystal morphology of phosphogypsum-based calcium sulfate dihydrate according to claim 2, characterized in that: in the step (2), the addition amount of the fatty alcohol is 30% of the phosphogypsum solution.
8. The method for regulating and controlling the crystal morphology of phosphogypsum-based calcium sulfate dihydrate according to claim 2, characterized in that: in the step (2), the stirring and heating time is 5min.
9. The method for regulating and controlling the crystal morphology of phosphogypsum-based calcium sulfate dihydrate according to claim 2, which is characterized in that: in the step (3), the drying time is 4h.
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104005086A (en) * | 2014-04-04 | 2014-08-27 | 贵阳中化开磷化肥有限公司 | Method for preparing calcium sulfate dihydrate crystal whisker from phosphorus gypsum |
| US20180273384A1 (en) * | 2015-09-18 | 2018-09-27 | Kingenta Norsterra Chemical Co., Ltd. | Method for producing wet-process phosphoric acid and by-producing alpha-hemihydrate gypsum and high-purity and high-whiteness alpha-hemihydrate gypsum |
| CN111850698A (en) * | 2020-07-21 | 2020-10-30 | 上海畅清生态环境科技有限公司 | Phosphogypsum whisker and preparation method thereof |
| CN114940508A (en) * | 2022-06-20 | 2022-08-26 | 湖北三峡实验室 | Process for settling and purifying phosphogypsum |
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- 2022-12-16 CN CN202211621346.4A patent/CN115974126A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104005086A (en) * | 2014-04-04 | 2014-08-27 | 贵阳中化开磷化肥有限公司 | Method for preparing calcium sulfate dihydrate crystal whisker from phosphorus gypsum |
| US20180273384A1 (en) * | 2015-09-18 | 2018-09-27 | Kingenta Norsterra Chemical Co., Ltd. | Method for producing wet-process phosphoric acid and by-producing alpha-hemihydrate gypsum and high-purity and high-whiteness alpha-hemihydrate gypsum |
| CN111850698A (en) * | 2020-07-21 | 2020-10-30 | 上海畅清生态环境科技有限公司 | Phosphogypsum whisker and preparation method thereof |
| CN114940508A (en) * | 2022-06-20 | 2022-08-26 | 湖北三峡实验室 | Process for settling and purifying phosphogypsum |
Non-Patent Citations (1)
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