CN112441608A - Preparation method of nano calcium hydroxide whisker - Google Patents

Preparation method of nano calcium hydroxide whisker Download PDF

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Publication number
CN112441608A
CN112441608A CN201910799318.3A CN201910799318A CN112441608A CN 112441608 A CN112441608 A CN 112441608A CN 201910799318 A CN201910799318 A CN 201910799318A CN 112441608 A CN112441608 A CN 112441608A
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crystal form
raw material
calcium sulfate
control agent
calcium hydroxide
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CN201910799318.3A
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CN112441608B (en
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丁文金
陈秋菊
孙红娟
彭同江
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Southwest University of Science and Technology
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Southwest University of Science and Technology
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    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01F—COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM, CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THE RARE-EARTH METALS
    • C01F11/00—Compounds of calcium, strontium, or barium
    • C01F11/46—Sulfates
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B82—NANOTECHNOLOGY
    • B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
    • B82Y30/00—Nanotechnology for materials or surface science, e.g. nanocomposites
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B82—NANOTECHNOLOGY
    • B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
    • B82Y40/00—Manufacture or treatment of nanostructures
    • C—CHEMISTRY; METALLURGY
    • C30—CRYSTAL GROWTH
    • C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
    • C30B29/00—Single crystals or homogeneous polycrystalline material with defined structure characterised by the material or by their shape
    • C30B29/10—Inorganic compounds or compositions
    • C—CHEMISTRY; METALLURGY
    • C30—CRYSTAL GROWTH
    • C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
    • C30B29/00—Single crystals or homogeneous polycrystalline material with defined structure characterised by the material or by their shape
    • C30B29/60—Single crystals or homogeneous polycrystalline material with defined structure characterised by the material or by their shape characterised by shape
    • C30B29/62—Whiskers or needles
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00—Particle morphology
    • C01P2004/60—Particles characterised by their size
    • C01P2004/64—Nanometer sized, i.e. from 1-100 nanometer
    • 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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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Organic Chemistry (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Nanotechnology (AREA)
  • Materials Engineering (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • General Physics & Mathematics (AREA)
  • Physics & Mathematics (AREA)
  • Inorganic Chemistry (AREA)
  • Metallurgy (AREA)
  • Manufacturing & Machinery (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Geology (AREA)
  • Composite Materials (AREA)
  • Crystals, And After-Treatments Of Crystals (AREA)
  • Compounds Of Alkaline-Earth Elements, Aluminum Or Rare-Earth Metals (AREA)

Abstract

The invention relates to a method for preparing nano calcium hydroxide whiskers by using a calcium sulfate raw material, which comprises the following steps: 1) grinding the calcium sulfate raw material to obtain calcium sulfate powder; 2) mixing the powder obtained in the step 1) according to an inorganic alkali solution with a liquid-solid ratio of 5-20 mL/g and a concentration of 0.5-5 mol/L and a crystal form control agent respectively, placing the mixture in a reaction container with stirring, and reacting for 30-120 min at 30-150 ℃ to obtain a solid-liquid mixture; 3) carrying out solid-liquid separation on the solid-liquid mixture obtained in the step 2) to obtain a filtrate and a filter cake, drying the filter cake at low temperature to obtain the nano calcium hydroxide whisker, wherein the filtrate can be recycled as a sulfate solution. The invention takes calcium sulfate powder as raw material, takes inorganic alkali as auxiliary agent, and adds crystal form control agent to prepare nano calcium hydroxide crystal whisker at low temperature and normal pressure; the crystal form control agent can be recycled. The material can be used for carbon dioxide adsorption or sewage treatment, and can also be used as a raw material for flue gas desulfurization or light calcium carbonate preparation.

Description

Preparation method of nano calcium hydroxide whisker
Technical Field
The invention relates to a preparation method of nano calcium hydroxide whiskers, in particular to a method for preparing whisker-shaped nano calcium hydroxide from a calcium sulfate raw material, and belongs to the field of inorganic functional materials and chemical materials.
Background
The calcium hydroxide is a binary strong base rich in calcium ions, can be applied to carbon dioxide adsorption, environmental protection neutralization, acidic wastewater and sewage treatment, boiler flue gas desulfurization and the like, can also be applied to high polymers as a filler, and has better reinforcing property when the fibrous nano calcium hydroxide is filled into the high polymers. At present, no public report about the preparation method of the nano calcium hydroxide whisker is found.
Disclosure of Invention
The invention aims to provide a method for preparing nano calcium hydroxide whiskers, which is a calcium sulfate raw material, is low in temperature and normal in pressure, is easy to realize industrially and has good applicability.
A preparation method of nano calcium hydroxide whiskers comprises the following steps:
1) grinding the calcium sulfate raw material to obtain calcium sulfate powder with the average particle size of 80-160 meshes;
2) mixing the calcium sulfate powder raw material obtained in the step 1) with an inorganic alkali solution and a crystal form control agent, placing the mixture in a reaction container with stirring, and reacting for 30-120 min at the temperature of 30-150 ℃ under normal pressure to obtain a solid-liquid mixture;
3) carrying out suction filtration, washing and drying on the solid-liquid mixture obtained in the step 2) to obtain solid powder taking sulfate solution and nano calcium hydroxide whiskers as main components.
The main chemical components in the calcium sulfate raw material in the step 1) are calcium sulfate, including natural gypsum, industrial byproduct gypsum and the like; the concentration of the inorganic alkali solution in the step 2) is 0.5-5 mol/L; the addition amount of the inorganic base is 5-20 mL/g of liquid-solid ratio; the inorganic alkali is one or more of sodium hydroxide, potassium hydroxide or magnesium hydroxide.
The addition amount of the crystal form control agent in the step 2) is 0.1-5% of the mass fraction of the raw materials; the crystal form control agent is one or more of sodium salicylate, EDTA, magnesium chloride or potassium phosphate.
The crystal form of the nano calcium hydroxide whisker prepared by the preparation method is portlandite, the appearance is fibrous, the diameter is 80-100 nm, and the length-diameter ratio is more than 20.
The method for preparing the nano calcium hydroxide whisker material has the following beneficial effects: 1) the raw materials used in the invention are natural gypsum or industrial by-product gypsum and the like, and the raw materials are easy to obtain and low in price; 2) the whole preparation process is carried out at low temperature and normal pressure, and is safe; 3) the crystal form control agent can be recycled, sulfate is a byproduct in the preparation process, and the preparation cost is low; 4) on the premise of reducing the dosage of chemical additives and shortening the production period, the purity of the prepared nano calcium hydroxide whisker can reach more than 90 percent and the length-diameter ratio of the whisker is more than 20.
Detailed Description
The invention relates to a preparation method of nano calcium hydroxide whiskers, which comprises the following steps.
1) Grinding the calcium sulfate raw material to obtain calcium sulfate powder with the average particle size of 80-160 meshes;
wherein, the main chemical components in the calcium sulfate raw material in the step 1) are calcium sulfate, mainly natural gypsum, industrial byproduct gypsum and the like.
2) Mixing the calcium sulfate powder raw material obtained in the step 1) with an inorganic alkali solution and a crystal form control agent, placing the mixture in a reaction container with stirring, and reacting for 30-120 min at the temperature of 30-150 ℃ under normal pressure to obtain a solid-liquid mixture;
wherein, the concentration of the inorganic alkali solution in the step 2) is 0.5-5 mol/L; the addition amount of the inorganic base is 5-20 mL/g of liquid-solid ratio; the inorganic alkali is one or more of sodium hydroxide, potassium hydroxide or magnesium hydroxide; the addition amount of the crystal form control agent is 0.1-5% of the mass fraction of the raw materials; the crystal form control agent is one or more of sodium salicylate, EDTA, magnesium chloride or potassium phosphate.
3) Carrying out suction filtration, washing and drying on the solid-liquid mixture obtained in the step 2) to obtain solid powder taking a sulfate solution and the nano calcium hydroxide whiskers as main components;
the filtrate obtained in the step 3) can be recycled, and the concentration of sulfate in the solution can be increased after the filtrate is recycled once, so that the precipitation and recovery of the sulfate are realized through the recycling; the crystal form control agent in the filtrate can be recycled.
The crystal form of the prepared nano calcium hydroxide whisker material is portlandite, the appearance is fibrous, the diameter is 80-100 nm, the length-diameter ratio is more than 20, and the content is more than 90.
The technical solution of the present invention is further described in detail by the following specific examples.
Example 1:
the calcium sulfate raw material in the embodiment is phosphogypsum, and the phosphogypsum comprises the following main chemical components in percentage by weight: SO (SO)340%，CaO30%，SiO25%, and the other 25%; the specific process comprises the following steps:
1) taking 10g of the phosphogypsum powder, preparing 120 mL of 1 mol/L sodium hydroxide solution, then pouring a phosphogypsum sample into the sodium hydroxide solution, adding 0.1 g of EDTA into the solution, stirring and reacting at 65 ℃ for 45 min, and after the reaction is finished, performing suction filtration and washing to obtain a solid reactant;
2) drying the solid reaction product at 60 ℃ for 12 h to obtain a nano calcium hydroxide whisker sample;
3) the calcium hydroxide whiskers contained in the obtained sample were 92.6%, and the whiskers had an average diameter of 87 nm and a length of 25 to 40 μm.
Example 2:
the calcium sulfate raw material in the embodiment is desulfurized gypsum, and the desulfurized gypsum comprises the following main chemical components in percentage by weight: SO (SO)326%，CaO48%，SiO21%, and the other 25%; the specific process comprises the following steps:
1) taking 10g of the desulfurized gypsum powder, preparing 80 mL of 1.5 mol/L magnesium hydroxide solution, then pouring a desulfurized gypsum sample into the magnesium hydroxide solution, adding 0.25 g of EDTA and 0.1 g of magnesium chloride into the solution, stirring and reacting at 78 ℃ for 83 min, and after the reaction is finished, carrying out suction filtration and washing to obtain a solid reactant;
2) drying the solid reaction product at 60 ℃ for 12 h to obtain a nano calcium hydroxide whisker sample;
3) the content of the nano calcium hydroxide whiskers in the obtained sample is 98.6%, the average diameter of the whiskers is 67 nm, and the length of the whiskers is 26-50 μm.

Claims (5)

1. A preparation method of nano calcium hydroxide whiskers comprises the following steps:
1) grinding the calcium sulfate raw material to obtain calcium sulfate powder with the average particle size of 80-160 meshes;
2) mixing the calcium sulfate powder raw material obtained in the step 1) with an inorganic alkali solution and a crystal form control agent, placing the mixture in a reaction container with stirring, and reacting for 30-120 min at the temperature of 30-150 ℃ under normal pressure to obtain a solid-liquid mixture;
3) carrying out suction filtration, washing and drying on the solid-liquid mixture obtained in the step 2) to obtain solid powder taking sulfate solution and nano calcium hydroxide whiskers as main components.
2. The method of claim 1, wherein: the main chemical components in the calcium sulfate raw material in the step 1) are calcium sulfate, including natural gypsum, industrial byproduct gypsum and the like; the concentration of the inorganic alkali solution in the step 2) is 0.5-5 mol/L; the addition amount of the inorganic base is 5-20 mL/g of liquid-solid ratio; the inorganic alkali is one or more of sodium hydroxide, potassium hydroxide or magnesium hydroxide.
3. The method of claim 1, wherein: in the step 2), the addition amount of the crystal form control agent is 0.1-5% of the mass fraction of the raw materials; the crystal form control agent is one or more of sodium salicylate, magnesium chloride, EDTA or potassium phosphate.
4. The method of claim 1, wherein: sulfate in the filtrate in the step 3) can be naturally precipitated and recovered through repeated recycling of the filtrate; the crystal form control agent in the filtrate can be recycled.
5. The production method according to claims 1 to 4, characterized in that: the preparation process of the nano calcium hydroxide whisker takes calcium sulfate as a main raw material, and the whole preparation process is finished at low temperature and normal pressure; the length-diameter ratio of the nano calcium hydroxide crystal whisker can be selectively controlled by controlling the proportion of the crystal form control agent in the preparation process; the crystal form of the nano calcium hydroxide whisker is portlandite, the shape is fibrous, the diameter is 80-100 nm, and the length-diameter ratio is more than 20.
CN201910799318.3A 2019-08-28 2019-08-28 Preparation method of nano calcium hydroxide whisker Active CN112441608B (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113856236A (en) * 2021-10-14 2021-12-31 昆明理工大学 Method for preparing nano material by regulating and controlling dissolution and crystallization of calcium-based solid waste through multiple physical fields

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113856236A (en) * 2021-10-14 2021-12-31 昆明理工大学 Method for preparing nano material by regulating and controlling dissolution and crystallization of calcium-based solid waste through multiple physical fields

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