CN110817828A - Method for preparing nano hydroxyapatite - Google Patents
Method for preparing nano hydroxyapatite Download PDFInfo
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- CN110817828A CN110817828A CN201810908151.5A CN201810908151A CN110817828A CN 110817828 A CN110817828 A CN 110817828A CN 201810908151 A CN201810908151 A CN 201810908151A CN 110817828 A CN110817828 A CN 110817828A
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B25/00—Phosphorus; Compounds thereof
- C01B25/16—Oxyacids of phosphorus; Salts thereof
- C01B25/26—Phosphates
- C01B25/32—Phosphates of magnesium, calcium, strontium, or barium
- C01B25/321—Methods for converting an alkaline earth metal ortho-phosphate into another ortho-phosphate
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- 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
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2002/00—Crystal-structural characteristics
- C01P2002/70—Crystal-structural characteristics defined by measured X-ray, neutron or electron diffraction data
- C01P2002/72—Crystal-structural characteristics defined by measured X-ray, neutron or electron diffraction data by d-values or two theta-values, e.g. as X-ray diagram
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/01—Particle morphology depicted by an image
- C01P2004/03—Particle morphology depicted by an image obtained by SEM
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/10—Particle morphology extending in one dimension, e.g. needle-like
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/10—Particle morphology extending in one dimension, e.g. needle-like
- C01P2004/16—Nanowires or nanorods, i.e. solid nanofibres with two nearly equal dimensions between 1-100 nanometer
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- 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
Abstract
The invention discloses a method for preparing Hydroxyapatite (HAP) powder, which comprises the following steps: calcium hydrogen phosphate CaHPO4·2H2CaCO, calcium carbonate3Adding the mixed solution and water into a hydrothermal tank, wherein the reaction temperature is 220 ℃, and the reaction time is 6 hours; wherein the hydroxyapatite HAP powder is pure phase powder with the particle size of more than 50 nm.
Description
Technical Field
The invention relates to the field of chemical synthesis, in particular to a method for synthesizing nano-grade hydroxyapatite by a chemical method.
Background
Among the large number of inorganic mineral components contained in human and animal bone, the main elements are Ca and P, and the mineral crystal structure formed by them is substantially identical to that of apatite formed under geological conditions, represented by hydroxyapatite (abbreviated as HAP). Physical and chemical properties of hydroxyapatite: melting point: 1650 ℃, specific gravity: 3.16g/cm3Ca/P: 1.67, pure hydroxyapatite powder is white, the crystal system is hexagonal system, has higher chemical stability, and Ca in the solution is in equilibrium with hydroxyapatite in a neutral aqueous solution system2+The concentration is less than 10-4mol/L, i.e. solubility in the order of 1ppm, is also a good explanation why animal and human bone material has been subject to various environmental attacks over the years and can also survive.
Early studies on the crystal size of bone minerals used X-ray diffraction (XRD) to calculate the apatite crystal size in bone, approximately 3-29 nm; with the application of electron microscopy, it has been considered that crystals have a plate shape of 50nm × 25nm × 10nm, and a rod shape of 25nm long and 5nm wide is also considered. Apatite in bone is the true nanoparticle in whatever result is closer to the real situation. Therefore, the preparation of the hydroxyapatite with the particle size less than 50nm can better meet the requirement of the bone cultural relics on the apatite.
In recent years, many advances have been made in the synthesis of nano-grade hydroxyapatite by various chemical methods, mainly including: dry synthesis, microemulsion method, precipitation method, sol-gel method, ultrasonic synthesis method, hydrolysis method, self-combustion method, hydrothermal method, etc. Among the above methods, the microemulsion method, precipitation method, sol-gel method, hydrothermal method, etc. which are reported in many documents are also called coacervation method, in which ions or molecules in a solution are controllably aggregated by physical or chemical means to form a colloid. "controlled" is the key to the overall manufacturing process, and by adjusting controllable factors, the properties of the product can be adjusted to obtain the desired product. The microemulsion method needs to use a large amount of organic phase and surfactant, the purification of the product is difficult, and the unknown damage of the residual impurities to the cultural relics is difficult to avoid. HAP synthesized by precipitation has a low particle size distribution and a small particle dispersion, and it has been reported that HAP powder of 30-80nm is prepared by using an additive or a freeze-drying method. The method has strict requirements on process conditions, and the prepared nano HAP particles have poor particle size uniformity and serious agglomeration phenomenon. The precursor obtained by the sol-gel method is combined with a hydrothermal method and the like for treatment, and has the characteristics of low preparation temperature, high reaction speed, high preparation efficiency, high powder purity and the like; but also has the defects of higher raw material price, possible pollution caused by organic solvent and the like.
Finding out proper technological process and reaction condition to prepare HAP powder material with grain size smaller than 50nm and high quality is the main task and aim of the research.
Disclosure of Invention
The invention discloses a method for preparing Hydroxyapatite (HAP) powder, which comprises the following steps:
calcium hydrogen phosphate CaHPO4·2H2CaCO, calcium carbonate3Adding a proper amount of water into a hydrothermal tank, wherein the reaction temperature is 200 ℃ and 250 ℃, and reactingThe time is 2-10 h; wherein CaHPO4·2H2O and CaCO3The molar ratio of (A) to (B) is 3: 2.
In one embodiment, the water is deionized water.
In one embodiment, the hydrothermal tank is made of polytetrafluoroethylene.
In one embodiment, the reaction temperature is 220 ℃ and the reaction time is 6 h.
In a specific embodiment, when the reaction temperature is 220 ℃ and the reaction time is 6 hours, the hydroxyapatite HAP powder is pure-phase powder with the particle size of less than 50 nm.
In one embodiment, the reaction temperature is 230 ℃ to 250 ℃, and the reaction time is 6 h.
In a specific embodiment, when the reaction temperature is 230-.
In a specific embodiment, the HAP powder prepared by heat preservation at 230 ℃ for 6 h: mainly comprises a rod shape with the length of 1-2 mu m and the width of 50-200nm and a plate shape with the length and the width of nanometer close to micron level.
In a specific embodiment, the HAP powder prepared by heat preservation at 240 ℃ for 6 h: mainly composed of a rod shape with the length of 2-5 μm and the width of 300-500nm and a plate shape with the length and the width of a few micrometers.
In one embodiment, the HAP powder prepared by heat preservation at 250 ℃ for 6 h: mainly columnar and granular in the micron scale.
In another aspect, the invention also discloses hydroxyapatite HAP powder prepared by using the method of any one of the above.
In one embodiment, the hydroxyapatite HAP powder is a pure phase powder having a particle size of less than 50 nm.
The invention also discloses the use of pure phase hydroxyapatite HAP powder with the particle size less than 50nm in preparing bone and mineral materials, wherein the method for preparing hydroxyapatite HAP powder comprises the following steps:
calcium hydrogen phosphate CaHPO4·2H2CaCO, calcium carbonate3And appropriate amount ofAdding ionized water into a water heating tank, wherein the reaction temperature is 220 ℃, and the reaction time is 6 h.
Advantageous effects
Compared with other powder preparation methods, the powder prepared by the hydrothermal method has very good performance, the hydrothermal reaction conditions, particularly the change of temperature, can influence the crystallization form and the crystal structure of the powder, and the powder prepared by the hydrothermal method has the following characteristics:
(1) the process of crystal growth in a controlled, sealed system allows the creation of certain phases that are difficult to obtain by other methods of preparing the material;
(2) the temperature required for growth is lower than that of most other methods for preparing powder, so that low-temperature homogenous isomers which cannot be obtained by other methods can be obtained;
(3) the growth area is in a constant temperature and equal concentration environment, and the change rate of the temperature is small;
(4) the growth process is mainly the growth of a thin phase, and the viscosity of the reaction concentration is very low.
Drawings
FIG. 1 shows a process for preparing HAP by hydrothermal synthesis.
FIG. 2 shows the XRD diffraction pattern of HAP powder prepared by the hydrothermal synthesis method.
FIG. 3 shows an SEM photograph of HAP powder prepared by hydrothermal synthesis at 220 ℃ for 6 hours.
FIG. 4 shows an SEM photograph of HAP powder prepared by hydrothermal synthesis at 230 ℃ for 6 hours.
FIG. 5 shows an SEM photograph of HAP powder prepared by hydrothermal synthesis at 240 ℃ for 6 hours.
FIG. 6 shows an SEM photograph of HAP powder prepared by hydrothermal synthesis at 250 ℃ for 6 hours.
Detailed Description
The present invention will be further illustrated by the following detailed description.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.
In this application, the singular forms "a", "an" and "the" include plural referents unless the context clearly dictates otherwise.
Definition of
The term "hydrothermal tank" as used herein is also referred to as a hydrothermal kettle, a hydrothermal reaction kettle, a polymerization kettle, a hydrothermal synthesis reaction kettle, a hydrothermal synthesis kettle. Is a sealed container capable of decomposing substances difficult to be accommodated.
The term "pure phase" as used herein refers to a substance having a single, identical physical and chemical property with a high concentration of phases. Phase-pure substances refer to a class of substances that consist only of the same chemical species (or molecules).
Examples
The invention is further illustrated by the following examples and figures. The examples are provided for illustrative purposes only and should not be construed as limiting the scope or content of the invention in any way.
Example 1: preparation method
CaHPO was used in this study4·2H2O and CaCO3Is a reactant, and has a chemical reaction formula: 6CaHPO4+4CaCO3→Ca10(PO4)6(OH)2+4CO2+2H2O in stoichiometric ratio of hydroxyapatite, i.e. CaHPO4·2H2O∶CaCO3The molar ratio of (A) to (B) is 3: 2, the mass ratio of (B) to (B) is 2.58: 1.
in the reaction conditions of the hydrothermal method, the two main conditions of the holding temperature and the holding time have different influences on the product. The research focuses more on the influence of temperature change in the control of reaction conditions, 10 ℃ is taken as a change gradient, and the heat preservation time is a relatively fixed median value through experiments.
1. Raw material table
The raw materials used in the process are shown in table 1. Wherein the purity of the raw materials is analytically pure.
TABLE 1 raw material table
2. Conventional apparatus
The conventional apparatus used in the process is shown in Table 2.
TABLE 2 Equipment table
3. Preparation method
The method specifically comprises the following steps: weighing calcium hydrogen phosphate (CaHPO) based on the stoichiometric ratio of hydroxyapatite4·2H2O) (AR, Shanghai reagent IV works) 51.6g, calcium carbonate (CaCO)3) (AR, Shanghai Si-Siji chemical Co., Ltd.) 30.0g, adding a proper amount of deionized water, then adding into a polytetrafluoroethylene hydrothermal tank, keeping the temperature in an oven at 200 ℃ and 250 ℃ for 2-10h, and obtaining white Hydroxyapatite (HAP) powder after the reaction is finished. After a plurality of tests, the heat preservation time is determined to be 6 hours, and the hydroxyapatite powder is successfully prepared by a hydrothermal synthesis method at different heat preservation temperatures. The specific process flow is shown in figure 1.
HAP powder Performance test
The measurement of the properties of the HAP powder comprises the steps of analyzing and measuring the phase of the prepared HAP powder by an XRD diffractometer, observing the morphology of the prepared HAP powder by a scanning electron microscope, and determining the particle size of a product.
4.1 XRD analysis of HAP powder
In the method, XRD diffraction analysis is carried out on the prepared HAP powder, and the powder prepared at the temperature of below 220 ℃ (200 ℃ and 210 ℃) can not obtain an effective characteristic peak, namely the HAP powder with pure phase can not be prepared; pure-phase HAP powder can be obtained at 220 ℃ and above (230 ℃, 240 ℃ and 250 ℃), and the heat preservation temperature is 6 h. The specific XRD diffraction pattern is shown in figure 2.
As can be seen from the XRD diffraction pattern, the HAP powder prepared by the hydrothermal synthesis method at the temperature of 220 ℃ (and above) is a pure-phase hydroxyapatite phase, which completely accords with the standard spectrum JSPDS 09-0432. That is, calcium hydrogen phosphate (CaHPO)4·2H2O) and calcium carbonate (CaCO)3) Is prepared from raw materials by hydrothermal synthesis at 220 deg.C or above for 6 hrHAP powder is successfully prepared; if the temperature is lower than 220 ℃, pure-phase HAP powder cannot be prepared.
4.2 SEM photograph of HAP powder
The morphology of the product of HAP powder prepared by hydrothermal synthesis at 220-250 ℃ for 6h is observed by an electron microscope (SEM), and the particle size of the powder is determined. According to the analysis of SEM pictures, the HAP powder prepared by the method is needle-shaped and plate-shaped, and is very consistent with the morphology of hydroxyapatite in the bone mineral mentioned above under an electron microscope, and the structure is favorable for HAP to be used as a filling material, so that the mechanical property of the HAP powder is improved.
1) SEM photograph of HAP powder under the condition of heat preservation at 220 ℃ for 6h
The HAP powder prepared under the condition mainly comprises a needle shape with the length of 40-50nm and the width of 2-5nm and a plate shape with the length of 50nm multiplied by 20nm multiplied by 2 nm. The SEM photographs are shown in FIGS. 3(A) and (B).
2) SEM photograph of HAP powder under the condition of heat preservation at 230-250 ℃ for 6h
And (3) insulating at 230 ℃ for 6h to prepare HAP powder: mainly composed of a rod shape with the length of 1-2 μm and the width of 50-200nm and a plate shape with the length and the width of nanometer close to micrometer level (figure 4).
And (3) insulating at 240 ℃ for 6h to prepare HAP powder: mainly composed of a rod shape 2-5 μm long and 300-500nm wide and a plate shape with a length and a width of several micrometers (FIG. 5).
And (3) heat preservation at 250 ℃ for 6h to prepare HAP powder: columnar and granular composition on the order of a few microns (fig. 6).
As can be seen from fig. 4, 5 and 6, the HAP powder grains prepared by hydrothermal synthesis at 230 ℃, 240 ℃ and 250 ℃ for 6h grow more completely with increasing temperature, grow larger in size and mainly consist of micron-sized powder.
The crystal grows under the condition of relatively low thermal stress in the hydrothermal process, so the probability of generating dislocation of the crystal prepared by the method is far less than that of the crystal prepared in a high-temperature melt.
In this study, calcium hydrogen phosphate (CaHPO) was used4·2H2O) and calcium carbonate (CaCO)3) Is used as a raw material and can be successfully prepared by a hydrothermal synthesis method at the temperature of 220 ℃ and 250 ℃ and keeping the temperature for 6hPure-phase nano-grade hydroxyapatite powder is prepared, but pure-phase hydroxyapatite powder cannot be prepared by heat preservation for 6 hours at the temperature of 200 ℃ and 210 ℃, and XRD diffraction patterns show that the prepared hydroxyapatite powder is pure-phase. The SEM photo shows that the hydroxyapatite powder is in a needle-shaped and plate-shaped nanometer crystal structure, and the structure is favorable for the hydroxyapatite powder to be used as a filling material and can improve the mechanical property of the hydroxyapatite powder.
Under the condition of the same heat preservation time (6 h), the particle size of the product obtained at the heat preservation temperature of 220 ℃ is less than 50nm, the requirement of the research is met, and the crystal size gradually grows along with the rise of the heat preservation temperature (230-250 ℃), and the particle size gradually increases from the nanometer level to the micrometer level. The particle size of the hydrothermal calcium hydroxy phosphate product reported in the literature is usually 100nm or higher, the product prepared by the research is less than 50nm, and the data range of the hydrothermal HAP preparation method is enriched. The HAP powder prepared by the research meets the expected requirements on shape, particle size and the like, and meets the description of hydroxyapatite of bone cultural relics in literature reports.
Is incorporated by reference
The entire disclosure of each patent and scientific literature cited herein is incorporated by reference for all purposes.
Equivalence of
The foregoing embodiments are merely illustrative of the principles and utilities of the present invention and are not intended to limit the invention. Many modifications may be made to the present invention without departing from the spirit or scope of the general inventive concept, and it will be apparent to those skilled in the art that changes and modifications may be made to the above-described embodiments without departing from the spirit or scope of the invention. Accordingly, it is intended that all equivalent modifications or changes which can be made by those skilled in the art without departing from the spirit and technical spirit of the present invention be covered by the claims of the present invention.
Claims (9)
1. A method for preparing hydroxyapatite HAP powder, comprising the steps of:
calcium hydrogen phosphate CaHPO4·2H2O, calcium carbonateCaCO3Adding water and water into a hydrothermal tank, wherein the reaction temperature is 200 ℃ and 250 ℃, and the reaction time is 2-10 h;
wherein CaHPO4·2H2O and CaCO3The molar ratio of (A) to (B) is 3: 2.
2. The method of claim 1, wherein the water is deionized water.
3. The method of claim 1, wherein the hydrothermal tank is a polytetrafluoroethylene material.
4. The process according to any one of claims 1 to 3, wherein the reaction temperature is 220 ℃ and the reaction time is 6 h.
5. The method of claim 4, wherein the hydroxyapatite HAP powder is a pure phase powder having a particle size of less than 50 nm.
6. The method as claimed in any one of claims 1 to 3, wherein the reaction temperature is 230 ℃ and 250 ℃ and the reaction time is 6 h.
7. The method of claim 6, wherein the hydroxyapatite HAP powder is a pure phase powder having a particle size greater than 50 nm.
8. Hydroxyapatite HAP powder prepared using the method of any one of the preceding claims.
9. Use of hydroxyapatite HAP powder according to claim 8 for the preparation of bone mineral material.
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| CN112938917A (en) * | 2021-01-28 | 2021-06-11 | 北京大学 | Preparation method of efficient nano-phosphate fertilizer and nano-phosphate fertilizer |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN112938917A (en) * | 2021-01-28 | 2021-06-11 | 北京大学 | Preparation method of efficient nano-phosphate fertilizer and nano-phosphate fertilizer |
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Application publication date: 20200221 |