Artificially synthesized jadeite and liquid-phase synthesis method thereof

Abstract

The invention belongs to the field of ceramic material synthesis, and discloses artificially synthesized jadeite and a liquid-phase synthesis method thereof. Natural low-quality jadeite is crushed by a crusher, magnetic black substances in the jadeite are removed through magnetic separation, purified powder is obtained after mixed acid pickling, and then the powder is subjected to high-temperature and high-pressure polymerization reaction to synthesize the artificial jadeite. The artificially synthesized jadeite prepared by adopting a liquid-phase high-temperature and high-pressure synthesis method has excellent density, gemstone characteristics and spectroscopic characteristics are basically consistent with those of natural jadeite, and the crystallinity is gt; 99%.

Description

Technical Field

[0001] The present invention belongs to the field of ceramic material synthesis, and particularly relates to an artificially synthesized jadeite and a liquid-phase synthesis method thereof. Background Art

[0002] Natural jadeite is much loved for its unique artistic qualities such as soft and elegant colors, gorgeous yet delicate beauty, and vivid green like dripping water. However, as a non-renewable resource, the market supply of natural jadeite is gradually decreasing due to large-scale mining and political influences.

[0003] Similar to the artificial synthesis technology of diamond, the high-temperature and high-pressure method is also the main method for artificially synthesizing jadeite. According to previous studies, the minimum pressure for the formation of jadeite is approximately 1.8 GPa, and the temperature range for the formation of jadeite expands as the pressure increases. This experiment verified that jadeite is formed under high-temperature and high-pressure conditions, and this result provided a theoretical basis for people to start artificially synthesizing jadeite. In the existing technology, most of the mainstream preparation processes for artificially synthesizing jadeite are to mix according to the chemical formula content ratio of jadeite and then adopt the high-temperature and high-pressure solid-phase synthesis method. However, the core problem of synthesizing jadeite by the high-temperature and high-pressure solid-phase synthesis method is that the melt viscosity is very large, the composition distribution is uneven, and it is difficult to fully achieve crystallization, resulting in rough texture of the product and not meeting the process requirements.

[0004] Chinese Patent CN101962284A discloses a method for synthesizing composite polycrystalline jadeite. This method uses aluminum hydroxide and sodium silicate as raw materials, and through a sodium hydroxide-catalyzed reaction, sodium aluminosilicate is generated. The obtained sodium aluminosilicate is then mixed and reacted with an inorganic acid solution and a sodium silicate solution to obtain sodium disilicate powder, which is the precursor of the jadeite component. Its disadvantage is that the preparation time is too long and the quality of the finished product is low.

[0005] Chinese Patent CN102060515A discloses a preparation process for synthesizing jadeite. This method refines and removes impurities from high-quality natural jadeite scraps, and then bonds the natural polycrystalline aggregate jadeite through a sintering process. Its disadvantage is that the quality requirements for raw materials are relatively high, and the quality of the sintered imitation is low.

[0006] Chinese Patent CN118439625A discloses a preparation method and application of an artificially synthesized jadeite precursor. This method uses sodium silicate nonahydrate, alumina, and silica powder as raw materials, and prepares the artificially synthesized jadeite precursor through mixed sintering, and then obtains the artificially synthesized jadeite through high-temperature and high-pressure synthesis. Its disadvantage is that in the synthesis process, the raw materials need to be melted first and then solidified into a solid glass body, and then solid-phase high-temperature and high-pressure synthesis is carried out. Moreover, the preparation steps are cumbersome, and the jadeite composition ratio is only a theoretical parameter, which has a certain gap with the composition of natural jadeite. Summary of the Invention

[0007] Aiming at the deficiencies of the existing technology, the purpose of the present invention is to provide a liquid-phase synthesis method for artificially synthesized jadeite to solve the problems existing in the prior art, such as high requirements for raw material quality, uneven distribution of chemical components, long preparation time, and low quality of finished products.

[0008] The purpose of the present invention is achieved through the following technical solutions.

[0009] The present invention provides a liquid-phase synthesis method for artificially synthesized jadeite, including the following steps:

[0010] (1) Natural low-quality jadeite is crushed by a crusher, screened, and magnetically separated to remove impurities.

[0011] (2) The jadeite powder after impurity removal in step (1) is pickled with a mixed acid, filtered by suction, washed with water, and dried to obtain jadeite precursor powder.

[0012] (3) The jadeite precursor powder in step (2) is pre-pressed into a shape, and the pre-pressed blank is placed in a high-temperature and high-pressure device for a synthesis reaction.

[0013] Preferably, in the above-mentioned liquid-phase synthesis method for artificially synthesized jadeite, in step (1), the sample has a high iron and calcium content, the iron content reaches more than 1.3%, the calcium element content reaches more than 0.3%, the overall color of the sample is gray, and the transparency is low.

[0014] Preferably, in the above-mentioned liquid-phase synthesis method for artificially synthesized jadeite, in step (1), the crushed jadeite powder is screened with a 150-200 mesh sieve.

[0015] Preferably, in the above-mentioned liquid-phase synthesis method for artificially synthesized jadeite, in step (1), the magnetic separation for impurity removal is to adsorb iron filings generated during the crushing process and other magnetic impurities inside the powder with a strong magnet.

[0016] Preferably, in the above-mentioned liquid-phase synthesis method for artificially synthesized jadeite, in step (1), the mixed acid is a mixed acid solution composed of any two or more of hydrochloric acid, sulfuric acid, nitric acid, and acetic acid. The mass of each acid in the mixed acid solution is the same, and the concentrations of hydrochloric acid, sulfuric acid, nitric acid, and acetic acid are all 1-3 mol / L. The preferred mixed acid combination is 2 mol / L acetic acid + 2 mol / L nitric acid + 2 mol / L hydrochloric acid + 1 mol / L sulfuric acid.

[0017] Preferably, in the above-mentioned liquid-phase synthesis method for artificially synthesized jadeite, in step (2), the pickling temperature is 60-75 °C, the pickling time is 6-8 h, and the mass ratio of the mixed acid solution to the jadeite powder is 2-3:1.

[0018] Preferably, in the above-mentioned liquid-phase synthesis method of artificial synthetic jadeite, in step (3), the pre-pressing and forming adopts a cold pressing and forming method, the pressure range of the green body is: 100 Mpa - 200 Mpa, and the size of the green body volume is: a cylinder with a diameter of Ф6 * 6 mm.

[0019] Preferably, in the above-mentioned liquid-phase synthesis method of artificial synthetic jadeite, in step (3), the conditions of the synthesis reaction are: first pressurize to 4 - 5 Gpa, then heat up to 850 - 900 °C and keep warm for 5 - 10 min, then heat up to 1600 - 1630 °C and keep warm for 10 - 15 min to ensure the sample melts, and finally cool down to 1450 - 1500 °C for synthesis for 30 - 40 min, and then cool down to room temperature at a cooling rate of 40 - 50 °C / min, and the pressure drops to 0 to obtain artificial synthetic jadeite.

[0020] The present invention also provides artificial synthetic jadeite prepared by the above liquid-phase synthesis method. Its structure is dense, the internal crystal grains are visible to the naked eye, the crystal grains are in the shape of short columns overlapping and distributed crosswise, and are similar to the structure of natural bean-type jadeite.

[0021] The present invention adopts a liquid-phase high-temperature and high-pressure synthesis technology. The raw materials are fully diffused in the liquid phase state, and the components can reach a higher uniformity in the molten state, creating favorable conditions for crystal growth, and finally obtaining artificial synthetic jadeite with a dense structure and uniform composition.

[0022] Compared with the prior art, the advantages and beneficial effects of the present invention are as follows:

[0023] (1) The raw materials of the present invention are simple, which are natural low-quality jadeite. After pickling and impurity removal, the utilization rate of resources is improved.

[0024] (2) Compared with the traditional solid-phase high-temperature and high-pressure synthesis method, in the liquid-phase high-temperature and high-pressure synthesis process of the present invention, the raw materials can be fully diffused in the liquid phase state, and the components can reach a higher uniformity in the molten state, creating favorable conditions for crystal growth. The liquid-phase high-temperature and high-pressure synthesis method of the present invention greatly increases the density of the sample and improves the quality of the synthetic jadeite.

[0025] (3) The jadeite synthesized by the method of the present invention has a vitreous luster. The test results of XRD, SEM, FT-IR, Raman, etc. show that the synthetic jadeite is basically consistent with natural jadeite in terms of gemological characteristics and structure, and its crystallinity > 99%. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art.

[0027] Figure 1Optical microscope image of the original jadeite in Example 1.

[0028] Figure 2 Optical microscope image of the pickled jadeite powder in Example 1.

[0029] Figure 3 Optical microscope image of the synthetic jadeite in Example 1.

[0030] Figure 4 XRD pattern of the synthetic jadeite in Example 1.

[0031] Figure 5 SEM image of the surface of the synthetic jadeite in Example 1.

[0032] Figure 6 SEM image of the fracture surface of the synthetic jadeite in Example 1.

[0033] Figure 7 FT-IR spectrum of the synthetic jadeite in Example 1.

[0034] Figure 8 Raman spectrum of the synthetic jadeite in Example 1.

[0035] Figure 9 SEM image of the surface of the synthetic jadeite in Comparative Example 1. Detailed implementation manners

[0036] The following combines the accompanying drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the protection scope of the present invention.

[0037] Example 1

[0038] A synthetic jadeite and its liquid-phase high-temperature and high-pressure synthesis method, comprising the following steps:

[0039] (1) Crush natural low-quality jadeite with a crusher, sieve the crushed jadeite powder through a 200-mesh sieve, and use a strong magnet to adsorb the iron filings generated during the crushing process and the remaining magnetic impurities inside the powder.

[0040] (2) Weigh the above - processed powder sample and put it into a beaker. Pour the acid solution combination of 2 mol / L acetic acid + 2 mol / L nitric acid + 2 mol / L hydrochloric acid + 1 mol / L sulfuric acid into the beaker, and the mass of each acid in the combination is the same. To make the reaction more complete, place the beaker in a magnetic - stirring water - bath pot and heat it in a water - bath at 75 °C for 8 h. After the reaction is completed, filter the sample mixed solution by suction, and repeatedly wash the sample powder with distilled water to ensure that the residual acid solution on the surface is completely removed. Finally, put the washed sample into an oven and dry it at 60 °C for 12 h to obtain the jadeite precursor.

[0041] (3) Cold - press the precursor to pre - form it into a cylinder with Ф6*6 mm, and then put it into a six - anvil press for synthesis. During synthesis, first pressurize to 5 GPa, then heat up to 900 °C and hold for 5 min, then heat up to 1630 °C and hold for 15 min to ensure that the sample melts. Finally, cool down to 1450 °C and synthesize for 30 min, and then cool down to room temperature at a cooling rate of 50 °C / min and reduce the pressure to 0 to obtain the synthetic jadeite sample.

[0042] The test results of XRD, SEM, FT - IR, Raman, etc. show that the synthetic jadeite in Example 1 is basically the same as natural jadeite in terms of gemological characteristics and structure.

[0043] Figure 1 It is the optical microscope image of the original jadeite powder in Example 1. It can be seen that the overall color of the original sample is gray and the transparency is extremely poor. The reason is that the contents of iron and calcium elements are relatively high, the iron content reaches more than 1.3%, and the calcium element content reaches more than 0.3%.

[0044] Figure 2 It is the optical microscope image of the pickled jadeite powder in Example 1. It can be seen that after pickling, the color of the powder becomes significantly white, showing a great improvement compared with the original sample.

[0045] Figure 3 It is the optical microscope image of the synthetic jadeite in Example 1. It can be seen that the texture of the sample is very similar to that of natural jadeite and has a vitreous luster.

[0046] Figure 4 It is the XRD pattern of the synthetic jadeite in Example 1. By comparing with the standard PDF card, it can be found that it is basically the same as the standard spectrum of NaAl(Si2O6) #22 - 1338, and no other impurity phases are observed.

[0047] Figure 5 It is the SEM image of the surface of the synthetic jadeite in Example 1. It can be observed from the figure that the synthetic jadeite synthesized by this method has good density and almost no pores on the surface.

[0048] Figure 6 SEM image of the fracture surface of the synthetic jadeite in Example 1. It can be observed from the figure that the grains in the sample exhibit a prismatic morphology, indicating that the crystallization transformation has been successfully achieved. The microstructure of this synthetic jadeite is highly similar to that of natural jadeite.

[0049] Figure 7 FT-IR spectrum of the synthetic jadeite in Example 1. It can be seen from the figure that the infrared absorption peaks of the synthetic jadeite sample are basically the same as those of natural jadeite, revealing the similarity and the consistency of the structural characteristics between synthetic jadeite and natural jadeite.

[0050] Figure 8 Raman spectrum of the synthetic jadeite in Example 1. Through Raman spectroscopy analysis, it can be found that the synthetic jadeite sample has the same ligand structure as natural jadeite, is composed of a pure phase, has a relatively large peak intensity and a sharp peak shape, indicating that the synthetic jadeite has excellent crystallinity.

[0051] Example 2

[0052] A synthetic jadeite and its liquid-phase high-temperature and high-pressure synthesis method, comprising the following steps:

[0053] (1) Crush natural low-quality jadeite with a crusher. The crushed jadeite powder needs to be sieved through a 200-mesh sieve, and iron filings generated during the crushing process and other magnetic impurities inside the powder are adsorbed by a strong magnet.

[0054] (2) Weigh the above-treated powder sample and put it into a beaker. Prepare an acid solution combination of 1 mol / L nitric acid + 1 mol / L hydrochloric acid, and the mass of each acid in the combination is the same. To make the reaction more complete, place the beaker in a magnetic stirring water bath and heat it in a water bath at 75 °C for 8 h. After the reaction is completed, filter the sample mixed solution by suction, and repeatedly wash the sample powder with distilled water to ensure that the residual acid solution on the surface is completely removed. Finally, put the washed sample into an oven and dry it at 60 °C for 12 h to obtain the jadeite precursor.

[0055] Cold-press the precursor into a Ф6*6 mm cylinder for pre-forming, and then put it into a cubic press for synthesis. During synthesis, first pressurize to 4 GPa, then heat up to 900 °C and hold for 10 min, then heat up to 1630 °C and hold for 15 min to ensure that the sample melts. Finally, cool down to 1500 °C and synthesize for 30 min, and then cool down to room temperature at a cooling rate of 40 °C / min, and reduce the pressure to 0 to obtain the synthetic jadeite sample.

[0056] Example 3

[0057] A synthetic jadeite and its liquid-phase high-temperature and high-pressure synthesis method, comprising the following steps:

[0058] (1) Crush natural low-quality jadeite with a crusher. The crushed jadeite powder needs to be sieved through a 200-mesh sieve, and iron filings generated during the crushing process and other magnetic impurities inside are adsorbed with a strong magnet.

[0059] (2) Weigh the above-treated powder sample and put it into a beaker. Pour the acid solution combination of 2 mol / L hydrochloric acid + 2 mol / L acetic acid into the beaker, and the mass of each acid in the combination is the same. To make the reaction more complete, place the beaker in a magnetic stirring water bath and heat it in a water bath at 75 °C for 8 h. After the reaction is completed, filter the sample mixed solution by suction, and repeatedly wash the sample powder with distilled water to ensure that the residual acid solution on the surface is completely removed. Finally, put the washed sample into an oven and dry it at 60 °C for 12 h to obtain the jadeite precursor.

[0060] Cold-press the precursor to pre-form it into a cylinder with a diameter of Ф6 * 6 mm, and then put it into a six-sided top press for synthesis. During synthesis, first pressurize to 5 GPa, then heat up to 850 °C and keep it warm for 10 min, then heat up to 1630 °C and keep it warm for 15 min to ensure that the sample melts. Finally, cool down to 1450 °C for synthesis for 40 min, and then cool down to room temperature at a cooling rate of 50 °C / min, and reduce the pressure to 0 to obtain the artificially synthesized jadeite sample.

[0061] Example 4

[0062] An artificially synthesized jadeite and its liquid-phase high-temperature and high-pressure synthesis method, comprising the following steps:

[0063] (1) Crush natural low-quality jadeite with a crusher. The crushed jadeite powder is sieved through a 200-mesh sieve, and iron filings generated during the crushing process and other magnetic impurities inside are adsorbed with a strong magnet.

[0064] (2) Weigh the above-treated powder sample and put it into a beaker. Pour the acid solution combination of 2 mol / L nitric acid + 2 mol / L hydrochloric acid + 1 mol / L sulfuric acid into the beaker, and the mass of each acid in the combination is the same. To make the reaction more complete, place the beaker in a magnetic stirring water bath and heat it in a water bath at 75 °C for 8 h. After the reaction is completed, filter the sample mixed solution by suction, and repeatedly wash the sample powder with distilled water to ensure that the residual acid solution on the surface is completely removed. Finally, put the washed sample into an oven and dry it at 60 °C for 12 h to obtain the jadeite precursor.

[0065] The precursor is cold-pressed into a preformed cylinder with a diameter of Ф6*6mm, and then placed in a six-sided press for synthesis. During synthesis, the pressure is first increased to 5Gpa, then the temperature is raised to 850°C and held for 5 minutes, then the temperature is further raised to 1600°C and held for 15 minutes to ensure the sample melts. Finally, the temperature is lowered to 1450°C for 30 minutes of synthesis, and then cooled to room temperature at a cooling rate of 40°C / min, and the pressure is reduced to 0 to obtain an artificially synthesized jadeite sample.

[0066] Example 5

[0067] An artificially synthesized jadeite and its liquid-phase high-temperature and high-pressure synthesis method, comprising the following steps:

[0068] (1) The natural low-quality jadeite is crushed by a crusher, and the crushed jadeite powder is sieved through a 200-mesh sieve, and the iron filings generated during the crushing process and the remaining magnetic impurities inside the powder are adsorbed by a strong magnet.

[0069] (2) Weigh the above-treated powder sample and put it into a beaker, and use an acid solution combination of 2mol / L nitric acid + 2mol / L hydrochloric acid + 2mol / L acetic acid, and the mass of each acid in the combination is the same. To make the reaction more complete, the beaker is placed in a magnetic stirring water bath, and under the condition of 75°C, it is heated in a water bath for 8 hours. After the reaction is completed, the sample mixed solution is filtered by suction, and the sample powder is repeatedly washed with distilled water to ensure that the residual acid solution on the surface is completely removed. Finally, the washed sample is placed in an oven and dried at 60°C for 12 hours to obtain a jadeite precursor.

[0070] (3) The precursor is cold-pressed into a preformed cylinder with a diameter of Ф6*6mm, and then placed in a six-sided press for synthesis. During synthesis, the pressure is first increased to 5Gpa, then the temperature is raised to 900°C and held for 5 minutes, then the temperature is further raised to 1630°C and held for 15 minutes to ensure the sample melts. Finally, the temperature is lowered to 1500°C for 30 minutes of synthesis, and then cooled to room temperature at a cooling rate of 50°C / min, and the pressure is reduced to 0 to obtain an artificially synthesized jadeite sample.

[0071] Example 6

[0072] An artificially synthesized jadeite and its liquid-phase high-temperature and high-pressure synthesis method, comprising the following steps:

[0073] (1) The natural low-quality jadeite is crushed by a crusher, and the crushed jadeite powder is sieved through a 200-mesh sieve, and the iron filings generated during the crushing process and the remaining magnetic impurities inside the powder are adsorbed by a strong magnet.

[0074] (2) Weigh the above - processed powder sample and put it into a beaker. Pour the acid solution combination of 2 mol / L acetic acid + 2 mol / L hydrochloric acid + 1 mol / L sulfuric acid into the beaker, where the mass of each acid in the combination is the same. To make the reaction more complete, place the beaker in a magnetic - stirring water - bath pot and heat it in a water - bath at 75 °C for 8 h. After the reaction is completed, perform suction filtration on the sample mixed solution, and repeatedly wash the sample powder with distilled water to ensure that the residual acid solution on the surface is completely removed. Finally, put the washed sample into an oven and dry it at 60 °C for 12 h to obtain the jadeite precursor.

[0075] (3) Cold - press the precursor into a pre - formed cylinder with a diameter of Ф6 * 6 mm, and then put it into a six - sided top press for synthesis. During synthesis, first pressurize to 4.5 GPa, then heat up to 850 °C and keep it at this temperature for 10 min, then heat up to 1630 °C and keep it at this temperature for 15 min to ensure that the sample melts. Finally, cool down to 1450 °C and synthesize for 30 min, and then cool down to room temperature at a cooling rate of 50 °C / min, and reduce the pressure to 0 to obtain the artificially synthesized jadeite sample.

[0076] Example 7

[0077] An artificially synthesized jadeite and its liquid - phase high - temperature and high - pressure synthesis method, comprising the following steps:

[0078] (1) Crush natural low - quality jadeite with a crusher. Sieve the crushed jadeite powder through a 200 - mesh sieve, and use a strong magnet to adsorb the iron filings generated during the crushing process and other magnetic impurities inside the powder.

[0079] (2) Weigh the above - processed powder sample and put it into a beaker. Pour the acid solution combination of 3 mol / L acetic acid + 3 mol / L nitric acid + 3 mol / L hydrochloric acid + 2 mol / L sulfuric acid into the beaker, where the mass of each acid in the combination is the same. To make the reaction more complete, place the beaker in a magnetic - stirring water - bath pot and heat it in a water - bath at 75 °C for 8 h. After the reaction is completed, perform suction filtration on the sample mixed solution, and repeatedly wash the sample powder with distilled water to ensure that the residual acid solution on the surface is completely removed. Finally, put the washed sample into an oven and dry it at 60 °C for 12 h to obtain the jadeite precursor.

[0080] (3) Cold - press the precursor into a pre - formed cylinder with a diameter of Ф6 * 6 mm, and then put it into a six - sided top press for synthesis. During synthesis, first pressurize to 4.5 GPa, then heat up to 900 °C and keep it at this temperature for 5 min, then heat up to 1630 °C and keep it at this temperature for 10 min to ensure that the sample melts. Finally, cool down to 1450 °C and synthesize for 40 min, and then cool down to room temperature at a cooling rate of 40 °C / min, and reduce the pressure to 0 to obtain the artificially synthesized jadeite sample.

[0081] Comparative Example 1

[0082] A synthetic method for artificial jadeite, comprising the following steps:

[0083] (1) Crush natural low-quality jadeite with a crusher, sieve the crushed jadeite powder through a 200-mesh sieve, and use a strong magnet to adsorb the iron filings generated during the crushing process and the remaining magnetic impurities inside the powder.

[0084] (2) Weigh the above-treated powder sample and put it into a beaker, pour the acid solution combination of 2mol / L acetic acid + 2mol / L nitric acid + 2mol / L hydrochloric acid + 1mol / L sulfuric acid into the beaker, and the mass of each acid in the combination is the same. To make the reaction more complete, place the beaker in a magnetic stirring water bath and heat it in a water bath at 75°C for 8 hours. After the reaction is completed, filter the sample mixed solution by suction, and repeatedly wash the sample powder with distilled water to ensure that the residual acid solution on the surface is completely removed. Finally, put the washed sample into an oven and dry it at 60°C for 12 hours to obtain a jadeite precursor.

[0085] (3) Cold press the precursor into a preformed cylinder with a diameter of Ф6*6mm, and then put it into a six-sided top press for synthesis. During synthesis, first pressurize to 5Gpa, then heat up to 900°C and hold for 5 minutes, then heat up to 1450°C for holding and synthesis, the synthesis time is 30 minutes, and then cool down to room temperature at a cooling rate of 50°C / min, and the pressure drops to 0 to obtain an artificial jadeite sample.

[0086] Figure 9 The SEM image of the surface of the artificial jadeite in Comparative Example 1 is shown. It can be observed that the surface is rough and there are obviously many pores, indicating that its density is poor.

[0087] Through Comparative Example 1 and Example 1, Figure 9 and Figure 5 By comparison, it can be found that during the liquid-phase synthesis process, atoms move freely in the liquid medium, and the atomic migration rate in this state is much higher than that of atoms in the solid phase. This high-speed atomic migration not only promotes the effective interaction between atoms but also can dynamically repair the defects inside the material, significantly reducing the defect density. In addition, the solvation effect during the liquid-phase synthesis process also promotes the directional arrangement of silicon-oxygen tetrahedrons along the c-axis. This arrangement helps to form a dense amorphous-to-crystalline transformation structure, further enhancing the density of the material. In the solid-phase synthesis process, since atoms are confined to diffuse in the lattice interstitial sites, this diffusion method is relatively difficult, and it is difficult to effectively eliminate or repair the pores and defects inside the material. Therefore, solid-phase synthesis samples often exhibit more pores and cracks.

Claims

1. A liquid phase synthesis method for artificially synthesizing jadeite, characterized in that: The following steps are involved: (1) Natural low-quality jadeite is crushed by a crusher, sieved, and magnetically separated to remove impurities; (2) washing the jadeite powder after impurities removal in step (1) with a mixed acid, filtering, washing with water, and drying to obtain a jadeite precursor powder; (3) Pre-pressing the jadeite precursor powder of step (2) into a mold, and placing the pre-pressed powder into a high-temperature and high-pressure device for a synthesis reaction.

2. The liquid phase synthesis method for artificial synthetic jade according to claim 1, characterized in that: In step (1), the iron content of the sample reaches more than 1.3%, the calcium content reaches more than 0.3%, and the overall color of the sample is gray with low transparency.

3. The liquid phase synthesis method for artificially synthesizing jadeite according to claim 1, characterized in that: In step (1), the crushed jade powder is sieved with a 150-200 mesh sieve.

4. The liquid phase synthesis method for artificially synthesizing jadeite according to claim 1, characterized in that: In step (1), the magnetic separation and impurity removal is to use a strong magnet to absorb the iron filings and other magnetic impurities in the powder produced during the crushing process.

5. The liquid phase synthesis method for artificial synthetic jade according to claim 1, characterized in that: In step (1), the mixed acid is a mixed acid solution composed of any two or more of hydrochloric acid, sulfuric acid, nitric acid and acetic acid, the mass of each acid in the mixed acid solution is the same, and the concentrations of hydrochloric acid, sulfuric acid, nitric acid and acetic acid are all 1-3 mol / L.

6. The liquid phase synthesis method for artificially synthesizing jadeite according to claim 1, characterized in that: In step (2), the pickling temperature is 60-75°C, the pickling time is 6-8h, and the mass ratio of the mixed acid solution to the jade powder is 2-3:

1.

7. The liquid phase synthesis method of an artificial synthetic jade material according to claim 1, characterized in that: In step (3), the pre-pressing is performed by cold pressing, and the green body pressure ranges from 100Mpa to 200Mpa.

8. The liquid phase synthesis method for artificial synthetic jade according to claim 1, characterized in that: In step (3), the conditions of the synthesis reaction are: first, pressurize to 4-5Gpa, then heat up to 850-900℃ and keep warm for 5-10min, then heat up to 1600-1630℃ and keep warm for 10-15min to ensure that the sample melts, and finally cool down to 1450-1500℃ for synthesis for 30-40min, then cool down to room temperature at a cooling rate of 40-50℃ / min, and reduce the pressure to 0 to obtain artificial synthetic jadeite.

9. Artificially synthesized jade obtained by the liquid phase synthesis method described in any one of claims 1 to 8.

10. The artificial synthetic jadeite according to claim 9, characterized in that: The gemological and spectroscopic characteristics of artificial jade are basically consistent with those of natural jade, and its crystallinity is >99%.

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