CN114455599A - Preparation method and application of rare earth or alkaline earth hexaboride liquid-phase dispersion - Google Patents
Preparation method and application of rare earth or alkaline earth hexaboride liquid-phase dispersion Download PDFInfo
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Abstract
A preparation method and application of a rare earth or alkaline earth hexaboride liquid-phase dispersion are disclosed, wherein the preparation method comprises the following steps: (1) uniformly mixing rare earth salt or alkaline earth salt and a boron source, heating to react under vacuum or inert atmosphere, and cooling to room temperature to obtain a primary product; (2) emulsifying the primary product in water, ultrasonically oscillating, filtering or centrifuging, washing, adding an alkaline aqueous solution into the washed product, emulsifying, and ultrasonically oscillating to obtain an aqueous phase dispersion; or after the water washing product is washed by alcohol to remove water, adding an organic solvent, emulsifying, and ultrasonically oscillating to obtain the organic phase dispersion. The liquid phase dispersion is applied to the preparation of transparent heat-insulating coatings, solar photo-thermal conversion nanofluids and seawater desalination devices. The liquid phase dispersion obtained by the method does not settle after standing for 12 months, and has good dispersibility and stability. The method has simple process and low cost, does not need drying, does not add any dispersant or surface treating agent, and can realize industrial production.
Description
Technical Field
The invention particularly relates to a preparation method and application of a rare earth or alkaline earth hexaboride liquid-phase dispersion.
Background
Rare earth and alkaline earth hexaboride (MB) having CsCl type cubic crystal structure6) Not only has the characteristics of high melting point, high hardness and strong chemical stability, but also has respective functionality. It is composed ofIn the material, trivalent rare earth hexaboride (LaB) with one abundant electron6、CeB6And PrB6Etc.) also has the characteristics of low volatility, low work function, etc., and is not only a cathode material with excellent thermionic emission performance, which is industrially mature to be applied, but also an ideal field emission cathode material; mixed valence compounds SmB6Has the property of a topological proximal rattan insulator; bivalent rare earth hexaboron compound EuB6Is a narrow bandgap semiconductor; divalent alkaline earth hexaboride (CaB)6、SrB6And BaB6) Can be used for thermoelectric materials. In particular, trivalent rare earth hexaboride (YB)6、LaB6And GaB6Etc.) the nano material has near infrared radiation with a local surface plasmon resonance absorption wavelength of 800-2500 nm, and simultaneously has strong absorption on the whole solar radiation, so the nano material not only can be applied to transparent solar radiation shielding materials for windows, but also can be applied to solar photothermal conversion and seawater desalination. However, in the conventional preparation, solid rare earth or alkaline earth hexaboride nano powder is prepared firstly, then a surface treatment agent is added, and the surface of the powder is modified by ball milling to prepare a liquid phase dispersion, and the rare earth or alkaline earth hexaboride nano particles prepared by the method are partially agglomerated before modification, so that the modified particles are large in size and are not uniformly distributed, the monodispersion of the rare earth or alkaline earth hexaboride nano material is difficult to realize, the dispersion performance is poor, and the absorption characteristic and the efficient solar energy absorption performance of the rare earth or alkaline earth hexaboride are difficult to realize. Thus, the dispersibility and stability of rare earth or alkaline earth hexaboride dispersions are key indicators in their use.
CN 106395843A and the literature (Powder Technology,2018,323: 203-. However, this method tends to form a layer of lanthanum oxide, boron oxide or amorphous boron on the surface of the nanoparticles, thereby affecting the dispersion stability of the aqueous dispersion thereof.
CN 1923686 a discloses a method for preparing nano hexaboride nano powder, which is prepared by mixing rare earth or alkaline earth source with boron source and reacting in a high pressure autoclave. However, the method needs high sealing pressure and is not easy for industrial production; in addition, due to the sealing reaction, the rare earth or alkaline earth source and the boron source are difficult to form boron defects in the nano powder, so that the surface of the nano particle is positively charged, and the aqueous dispersion is difficult to prepare; the rare earth or alkaline earth source also absorbs water easily, and some impurities of rare earth or alkaline earth borate are easily generated.
CN 106009884A discloses lanthanum hexaboride nano heat-insulating water-based slurry and a preparation method thereof, wherein the surface activity of lanthanum hexaboride nano particles is improved by adding different active agents, and the preparation of the nano lanthanum hexaboride heat-insulating water-based slurry is realized. However, it is not possible to achieve the direct dispersion of nano lanthanum hexaboride in water without adding a dispersant.
In conclusion, the rare earth hexaboride prepared by the existing method has to be washed by acid to remove the impurities of the boric acid rare earth, and in order to ensure the stability of the prepared dispersoid, a surface treating agent has to be added, and hard agglomeration is formed after drying, so that the particle diameter of the modified particles is large, the distribution is not uniform, and the dispersibility is seriously influenced. Therefore, a method for preparing the rare earth or alkaline earth hexaboride liquid phase dispersion which has the advantages of simple process, low cost, no need of drying, no addition of any dispersing agent and excellent dispersion and stability of the obtained dispersion is needed to be found.
Disclosure of Invention
The invention aims to solve the technical problem of overcoming the defects in the prior art and provide a preparation method and application of a rare earth or alkaline earth hexaboride liquid phase dispersion, which have the advantages of simple process, low cost, no need of drying, no addition of any dispersing agent, realization of industrial production, excellent dispersion and stability of the obtained dispersion and strong near infrared absorption and scattering capability.
The technical scheme adopted by the invention for solving the technical problems is as follows: a method for preparing a liquid phase dispersion of a rare earth or alkaline earth hexaboride compound comprising the steps of:
(1) uniformly mixing rare earth salt or alkaline earth salt and a boron source, heating to react under vacuum or inert atmosphere, and cooling to room temperature to obtain a primary product;
(2) emulsifying the primary product obtained in the step (1) in water, carrying out ultrasonic oscillation, filtering or centrifuging, washing with water, adding an alkaline aqueous solution into the washing product, emulsifying, and carrying out ultrasonic oscillation to obtain a rare earth or alkaline earth hexaboride aqueous phase dispersoid; or after the washing product is washed by alcohol to remove water, adding an organic solvent, emulsifying, and ultrasonically oscillating to obtain the rare earth or alkaline earth hexaboride organic phase dispersion.
Preferably, in the step (1), the molar ratio of the rare earth element in the rare earth salt or the alkaline earth element in the alkaline earth salt to the boron element in the boron source is 1: 2-12 (more preferably 1: 5-10). The boron source is easy to decompose into gas phase and then is lost, so the dosage of the boron source can be properly excessive compared with rare earth or alkaline earth elements, but the boron defect exists in the synthesized nano hexaboride powder whether the dosage is excessive or not, and the surface of the hexaboride nano particle is positively charged.
Preferably, in the step (1), the rare earth salt is one or more of rare earth chloride, rare earth oxychloride, rare earth fluoride or rare earth bromide. More preferably, the rare earth salt is a rare earth chloride and/or a rare earth oxychloride. The melting points of the rare earth chloride and the rare earth oxychloride are low, the liquid phase is easier to form, the reduction is easy, and the particle size of the synthesized hexaboride nano-particles is small, so that the dispersion is facilitated. The rare earth elements in the rare earth salt are rare earth metal elements with atomic numbers of 57-71 and one or more of metal elements Sc and Y.
Preferably, in the step (1), the alkaline earth salt is one or more of chlorinated alkaline earth, chlorine oxidized alkaline earth, fluorinated alkaline earth or brominated alkaline earth. More preferably, the alkaline earth salt is an alkaline earth chloride and/or an alkaline earth oxychloride. The alkaline earth element in the alkaline earth salt is one or more of calcium, strontium or barium.
Preferably, in step (1), the boron source is an alkali metal borohydride.
Preferably, the alkali metal borohydride is NaBH4、KBH4Or LiBH4And the like.
Preferably, in the step (1), the vacuum degree of the vacuum is 0-100 Pa.
Preferably, in step (1), the inert atmosphere is argon and/or helium. The inert atmosphere used by the method is high-purity gas with the purity of more than or equal to 99.9 percent.
Preferably, in step (1), the specific operation of the temperature-rising heating reaction is as follows: the temperature is raised to 300-400 ℃ at the speed of 5-20 ℃/min, the temperature is maintained for 1-5 h, then the temperature is raised to 400-1200 ℃ at the speed of 1-30 ℃/min, and the temperature is maintained for 1-10 h more preferably 600-1000 ℃. The method is characterized in that heat preservation is carried out at a lower temperature of 300-400 ℃ so as to fully remove residual moisture, and the moisture mainly comes from the following sources: firstly, the moisture contained in the raw material; secondly, the rare earth salt or the alkaline earth salt which is easy to absorb water absorbs the water in the air in the mixing process; if the water content is excessive, boric acid rare earth or boric acid alkaline earth is easily generated, which not only seriously affects the purity of the hexaboride nano material, but also can be removed only by acid washing, and the acid washing can destroy the surface charge of hexaboride nano particles, thereby seriously affecting the dispersion of rare earth or alkaline earth hexaboride in water.
Preferably, in the step (1), the cooling is performed at a rate of 5 to 40 ℃/min (more preferably 10 to 30 ℃/min) to room temperature.
Preferably, in the step (1), a low melting point medium which is 1 to 20 times (more preferably 1 to 10 times) of the total mass of the rare earth salt or the alkaline earth salt and the boron source is added.
Preferably, the low-melting-point medium is low-melting-point elemental metal or low-melting-point molten salt.
Preferably, the low-melting-point elemental metal is one or more of elemental Sn, elemental In, elemental Bi and the like. The melting point of the low-melting-point elementary metal is lower than 300 ℃, so that the reaction temperature is favorably reduced. Through the high-temperature metal liquid phase environment provided by the low-melting point elemental metal, on one hand, the loss of borane generated by the thermal decomposition of a boron source can be reduced, so that the rare earth salt or the alkaline earth salt and the boron source react more quickly and sufficiently, the yield is improved, and the method is suitable for industrial production; on the other hand, the method skillfully solves the inherent problems of high reaction temperature, long atom diffusion path, serious boron source loss, incomplete reaction and the like of the rare earth or alkaline earth hexaboride nano powder prepared by the conventional solid phase reaction method. The low-melting point elemental metal can be recycled after the reaction is finished.
Preferably, the low-melting-point molten salt is LiCl, KCl, NaCl or ZnCl2And the like. More preferably, the low melting point molten salt is KCl, LiCl and ZnCl2The mass ratio of (A) to (B) is 1-4: 1.
Preferably, in the step (2), the volume-to-mass ratio (mL/g) of the water to the total mass of the raw materials in the step (1) is 3-10: 1. The raw materials are rare earth salt or alkaline earth salt and boron source, or low melting point medium is also included.
Preferably, in the step (2), the power of the emulsification treatment is 0.5-40 kW (more preferably 1-10 kW), the rotating speed is 1000-30000 r/min, and the time of each emulsification treatment is 20-40 min. The mechanical shearing force in the emulsification treatment process reduces the size of solid particles in the nano material through grinding or crushing, and can quickly play a role of loosening.
Preferably, in the step (2), the frequency of the ultrasonic oscillation is 10 to 50kHz (more preferably 20 to 50 kHz), and the time of each ultrasonic oscillation is 10 to 180 min (more preferably 50 to 150 min). The ultrasonic oscillation has the effect of dispersing the hexaboride primary product more, so that the halide salt or molten salt with low melting point generated in the hexaboride primary product is dissolved in water.
Preferably, in the step (2), the temperature of the water washing is 10 to 80 ℃ (more preferably 40 to 70 ℃). The purpose of the water wash is to remove the halide salt formed or also the low melting point molten salt.
Preferably, in the step (2), the emulsification treatment, the ultrasonic oscillation, the filtration or the centrifugation and the water washing are repeatedly carried out for more than or equal to 3 times, and AgNO is dripped into the water washing liquid3Or Ca (OH)2The solution was free of white precipitate. When the rare earth salt or the alkaline earth salt contains chlorine or bromine, AgNO is dripped3Solution, no white precipitate indicating chloride or bromide ions in solutionCompletely removing; when the rare earth salt or the alkaline earth salt contains fluorine, Ca (OH) is dripped2Solution, no white precipitate indicated complete removal of fluoride ions from the solution.
Preferably, in the step (2), when the low-melting-point medium is a low-melting-point elemental metal, after the first emulsification treatment and the ultrasonic oscillation, the pH value is adjusted to 9-10 by using an alkaline aqueous solution, the mixture is kept stand, the low-melting-point elemental metal is separated, then the filtration or the centrifugation is carried out, the washing is carried out, the emulsification treatment, the ultrasonic oscillation and the filtration are repeated, the washing operation is not less than 2 times, and AgNO is dropwise added into the washing liquid3Or Ca (OH)2The solution was free of white precipitate. After the pH value is adjusted to 9-10, rare earth or alkaline earth hexaboride can be dispersed in water, and low-melting-point elemental metal can be precipitated in the standing process, so that the separation and recycling are facilitated.
Preferably, the pH value of the alkaline aqueous solution for adjusting the pH value is more than or equal to 10.
Preferably, the alkaline aqueous solution is an aqueous sodium hydroxide solution or an aqueous ammonia solution.
Preferably, the standing time is 5-30 h.
Preferably, in the step (2), the volume mass ratio (L/g) of the alkaline aqueous solution or the organic solvent to the dry weight of the water-washed product is 5-1000: 1 (more preferably 6-600: 1). After the dry weight proportion in the washing product is determined by a conventional method, the washing product needing to be added under a certain dry weight can be calculated, and the fact that the washing product needs to be dried is not implied. The method of the invention is to directly add alkaline aqueous solution or organic solvent into wet-based water-washing products for dispersion, which can reduce drying steps and save energy, and the more important reason is that the inventor researches and discovers that once rare earth or alkaline earth hexaboride is dried, ball milling is needed and dispersing agent is added to disperse in water, the dispersing performance is greatly reduced even can not disperse, wet-based water is directly dispersed, no surface treating agent is needed to be added, and after the pH value is adjusted to 9-10, stable hexaboride liquid phase dispersion which does not settle after standing for 12 months can be realized, the primary analysis reason is that the surfaces of hexaboride nano particles are positively charged, negative ions in adsorbed water form an electric double layer, and the electric double layer is overlapped to mutually repel the nano particles to form stable dispersion.
Preferably, in the step (2), the pH value of the alkaline aqueous solution is 9-10.
Preferably, in the step (2), the alkaline aqueous solution is an aqueous sodium hydroxide solution or an aqueous ammonia solution.
Preferably, in the step (2), the number of times of washing water with alcohol is more than or equal to 2.
Preferably, in the step (2), the organic solvent is one or more of an alcoholic solution, an ionic liquid, grease, or a liquid resin.
Preferably, in the step (2), the alcohol used for washing water with alcohol and the alcohol solution are one or more of ethanol, ethylene glycol or n-butanol.
Preferably, in the step (2), the ionic liquid is 1-hexyl-3-methylimidazole bistrifluoromethylsulfonyl imide salt and/or 1-butyl-3-methylimidazole tetrafluoroborate salt and the like. The ionic liquid is the ionic liquid with wide liquid temperature range (namely liquid process).
The technical scheme adopted for further solving the technical problems is as follows: the application of the rare earth or alkaline earth hexaboride liquid-phase dispersion obtained by the preparation method in preparing transparent heat-insulating coatings, solar photo-thermal conversion nanofluids and seawater desalination devices is provided. Compared with the existing dispersion, the dispersion obtained by the method has better dispersibility, and can avoid the agglomeration of nano particles to form larger secondary particles, thereby improving the transparent heat-insulating property of a coating and the photo-thermal conversion efficiency of the nano fluid and a seawater desalination device thereof.
The invention has the beneficial effects that:
(1) the rare earth or alkaline earth hexaboride liquid phase dispersoid obtained by the method utilizes positive charges on the surface of the nano particles, can realize sealed standing for 12 months without sedimentation by adjusting the pH value of the solution, and has good stability, the one-dimensional size of the nano particles of the dispersoid is 5-30 nm, and the dispersity is good;
(2) the method has simple process and low cost, does not need drying, does not add any dispersant or surface treating agent, and can realize industrial production;
(3) the rare earth or alkaline earth hexaboride liquid-phase dispersion obtained by the method has strong near infrared absorption and scattering capability, and can be widely used for preparing transparent heat-insulating coatings, solar photo-thermal conversion nanofluids and seawater desalination devices.
Drawings
FIG. 1 is an X-ray diffraction pattern of an aqueous dispersion of lanthanum hexaboride obtained in example 1 of the present invention;
FIG. 2 is a scanning electron micrograph of a lanthanum hexaboride aqueous dispersion obtained in example 1 of the present invention;
FIG. 3 is a graph of the UV-visible near-IR absorption spectrum of nanoparticles in an aqueous dispersion of lanthanum hexaboride obtained in example 1 of the present invention;
FIG. 4 is a graph showing the sedimentation of the aqueous lanthanum hexaboride dispersion obtained in example 1 of the present invention after it has been left standing for 12 months.
Detailed Description
The invention is further illustrated by the following examples and figures.
The density of the ethanol used in the embodiment of the invention is 0.79g/mL, and the density of the n-butanol is 0.81 g/mL; the 1-hexyl-3-methylimidazole bistrifluoromethanesulfonimide salt used in the embodiment of the invention is purchased from the Mini chemical technology (Shanghai) Co., Ltd, and the density is 1.37g/mL, and the 1-butyl-3-methylimidazole tetrafluoroborate salt is purchased from the Beijing Bailingwei technology Co., Ltd, and the density is 1.21 g/mL; the purity of the high-purity gas used by the method is more than or equal to 99.9 percent; the chemical reagents used in the examples of the present invention, unless otherwise specified, are commercially available in a conventional manner.
Example 1
(1) 1.25 g (5 mmol) of LaCl3With 1.52 g (40 mmol) NaBH4Uniformly mixing, putting into an alumina crucible, carrying out heating reaction at a high-purity argon atmosphere, heating to 400 ℃ at a speed of 10 ℃/min, preserving heat for 1h, heating to 750 ℃ at a speed of 20 ℃/min, preserving heat for 3h, and cooling to room temperature at a speed of 20 ℃/min to obtain an initial product;
(2) the first step obtained in the step (1)Emulsifying the product in 15mL water (power of 3kW, rotation speed of 20000r/min, time of each emulsification treatment of 30 min), ultrasonic oscillating (frequency of 40kHz, time of each ultrasonic oscillating of 100 min), filtering, washing with 50 deg.C water for 3 times, and adding AgNO dropwise into the water washing solution3Until the solution has no white precipitate, adding 9.5mL of sodium hydroxide solution with pH value of 9.5 into 0.5g (dry weight) of water-washed product, emulsifying for 30min at power of 3kW and rotation speed of 20000r/min, and ultrasonically oscillating for 100min at frequency of 40kHz to obtain lanthanum hexaboride aqueous phase dispersoid;
washing 0.5g (dry weight) of water-washed product with ethanol for 3 times, adding 1-hexyl-3-methylimidazole bistrifluoromethanesulfonylimide salt 6.9mL, emulsifying for 30min at the power of 3kW and the rotation speed of 20000r/min, and ultrasonically oscillating for 100min at the frequency of 40kHz to obtain the lanthanum hexaboride ionic liquid-phase dispersion.
As shown in fig. 1, lanthanum hexaboride in the aqueous lanthanum hexaboride dispersion obtained in the embodiment of the present invention is LaB6Pure phase, without any other impurity phases.
As shown in fig. 2, lanthanum hexaboride in the lanthanum hexaboride aqueous phase dispersion obtained in the embodiment of the invention has good dispersibility, no agglomeration phenomenon occurs, and the one-dimensional size of nanoparticles of the dispersion is 10-30 nm.
As shown in fig. 3, the lanthanum hexaboride aqueous dispersion obtained in the embodiment of the present invention has high absorption capacity in ultraviolet, visible, and near infrared bands, and can be used in the fields of thermal insulation and optics.
As shown in fig. 4, the aqueous lanthanum hexaboride dispersion obtained in the example of the present invention is black, has a solid content of 5wt%, and does not settle after being sealed and left for 12 months.
Through detection, the lanthanum hexaboride ion liquid phase dispersoid obtained in the embodiment of the invention is black, has the solid content of 5wt%, and does not settle after being sealed and kept stand for 12 months.
Example 2
(1) 1.24 g (5 mmol) of CeCl3And 1.14 g (30 mmol) NaBH4With 6.64g KCl, 5.21g LiCl and 2.38g ZnCl2Mixing, loading into alumina crucible, heating under high-purity argon atmospherePerforming thermal reaction, namely heating to 300 ℃ at the speed of 15 ℃/min, preserving heat for 2h, heating to 700 ℃ at the speed of 30 ℃/min, preserving heat for 5h, and cooling to room temperature at the speed of 30 ℃/min to obtain a primary product;
(2) emulsifying the primary product obtained in the step (1) in 100mL of water (the power is 4kW, the rotating speed is 30000r/min, the time of each emulsifying treatment is 20 min), ultrasonically oscillating (the frequency is 40kHz, the time of each ultrasonic oscillation is 50 min), filtering and washing with water at the temperature of 60 ℃ for 4 times, and dripping AgNO into the water washing liquid3Until the solution has no white precipitate, adding 4.5mL of ammonia water solution with pH value of 9.0 into 0.5g (dry weight) of water-washed product, emulsifying for 20min at power of 4kW and rotation speed of 30000r/min, and ultrasonically oscillating for 50min at frequency of 40kHz to obtain cerium hexaboride aqueous phase dispersoid;
washing 0.5g (dry weight) of water-washed product with n-butanol for 4 times, adding 3.7mL of 1-butyl-3-methylimidazole tetrafluoroborate, emulsifying at a rotation speed of 30000r/min and a power of 4kW for 20min, and ultrasonically oscillating at a frequency of 40kHz for 50min to obtain the cerium hexaboride ion liquid-phase dispersion.
Through detection, cerium hexaboride in the cerium hexaboride aqueous phase dispersion obtained in the embodiment of the invention is CeB6Pure phase, without any other impurity phases.
Through detection, the cerium hexaboride in the cerium hexaboride aqueous phase dispersion obtained in the embodiment of the invention has good dispersibility, no agglomeration phenomenon occurs, and the one-dimensional size of the nano particles of the dispersion is 5-20 nm.
Through detection, the cerium hexaboride aqueous dispersion obtained in the embodiment of the invention has high absorption capacity in ultraviolet, visible and near infrared bands, and can be used in the fields of heat insulation and optics.
Through detection, the cerium hexaboride aqueous dispersion obtained in the embodiment of the invention is black, has the solid content of 10wt%, and does not settle after being sealed and kept stand for 12 months; the cerium hexaboride ionic liquid phase dispersoid obtained in the embodiment of the invention is black, has the solid content of 10wt%, and does not settle after being sealed and kept stand for 12 months.
Example 3
(1) 2.45 g (10 mmol) of LaCl3And 2.65 g (70) mmol）NaBH4Uniformly mixing the powder with 5.11g (43 mmol) of Sn powder, putting the mixture into an alumina crucible, carrying out heating reaction under the atmosphere of high-purity helium, heating to 400 ℃ at the speed of 5 ℃/min, preserving heat for 1h, heating to 750 ℃ at the speed of 10 ℃/min, preserving heat for 1h, and cooling to room temperature at the speed of 10 ℃/min to obtain a primary product;
(2) emulsifying the primary product obtained in the step (1) in 100mL of water (the power is 2kW, the rotating speed is 10000r/min, the time of each emulsifying treatment is 40 min), ultrasonically oscillating (the frequency is 50kHz, the time of each ultrasonic oscillation is 120 min), adjusting the pH value to 9.3 by using a sodium hydroxide solution with the pH value of 11, standing for 24h, separating Sn powder, filtering and washing at 40 ℃, repeating the emulsifying treatment, the ultrasonic oscillation, the filtering and the washing for 3 times, and dropwise adding AgNO into a washing liquid3Until the solution has no white precipitate, adding 99mL of ammonia water solution with pH value of 9.5 into 1g (dry weight) of water-washed product, emulsifying for 40min at power of 2kW and rotation speed of 10000r/min, and ultrasonically oscillating for 120min at frequency of 50kHz to obtain lanthanum hexaboride aqueous phase dispersoid;
washing 1g (dry weight) of water-washed product with ethanol for 3 times, adding 125.3mL of ethanol, emulsifying for 40min at the power of 2kW and the rotation speed of 10000r/min, and ultrasonically oscillating for 120min at the frequency of 50kHz to obtain the lanthanum hexaboride alcohol phase dispersoid.
Through detection, lanthanum hexaboride in the lanthanum hexaboride aqueous phase dispersoid obtained in the embodiment of the invention is LaB6Pure phase, without any other impurity phases.
Through detection, the lanthanum hexaboride in the lanthanum hexaboride aqueous phase dispersoid obtained in the embodiment of the invention has good dispersity, no agglomeration phenomenon occurs, and the one-dimensional size of the nanoparticles of the dispersoid is 10-30 nm.
Through detection, the lanthanum hexaboride aqueous phase dispersoid obtained in the embodiment of the invention has high absorption capacity in ultraviolet, visible and near infrared bands, and can be used in the fields of heat insulation and optics.
Through detection, the lanthanum hexaboride aqueous dispersion obtained in the embodiment of the invention is black, the solid content is 1wt%, and the lanthanum hexaboride aqueous dispersion is sealed and kept stand for 12 months without sedimentation; the lanthanum hexaboride alcohol phase dispersoid obtained in the embodiment of the invention is black, has the solid content of 1 weight percent, and does not settle after being sealed and kept stand for 12 months.
Example 4
(1) 1.75g (10 mmol) of BaF2With 2.70g (50 mmol) of KBH4Uniformly mixing, putting into an alumina crucible, carrying out heating reaction under the vacuum of 60 Pa, heating to 350 ℃ at the speed of 20 ℃/min, preserving heat for 3h, heating to 800 ℃ at the speed of 20 ℃/min, preserving heat for 2h, and cooling to room temperature at the speed of 20 ℃/min to obtain an initial product;
(2) emulsifying the primary product obtained in the step (1) in 20mL of water (the power is 3kW, the rotating speed is 20000r/min, the time of each emulsifying treatment is 30 min), ultrasonically oscillating (the frequency is 30kHz, the time of each ultrasonic oscillation is 100 min), filtering and washing at 50 ℃ for 3 times, and dripping Ca (OH) into the washing liquid2Until the solution has no white precipitate, adding 199mL of sodium hydroxide solution with the pH value of 10.0 into 1g (dry weight) of water washing product, emulsifying for 30min at the power of 3kW and the rotating speed of 20000r/min, and ultrasonically oscillating for 100min at the frequency of 30kHz to obtain barium hexaboride aqueous phase dispersoid;
washing 1g (dry weight) of water-washed product with n-butanol for 3 times, adding 245.7mL of n-butanol, emulsifying at a power of 3kW and a rotation speed of 20000r/min for 30min, and ultrasonically oscillating at a frequency of 30kHz for 100min to obtain the lanthanum hexaboride alcohol phase dispersion.
Through detection, the barium hexaboride in the barium hexaboride aqueous phase dispersoid obtained in the embodiment of the invention is BaB6Pure phase, without any other impurity phases.
Detection shows that the barium hexaboride in the barium hexaboride aqueous phase dispersoid obtained in the embodiment of the invention has good dispersibility, no agglomeration phenomenon, and the one-dimensional size of the nano particles of the dispersoid is 5-30 nm.
Through detection, the barium hexaboride aqueous phase dispersoid obtained in the embodiment of the invention has high absorption capacity in ultraviolet, visible and near infrared bands, and can be used in the fields of heat insulation and optics.
Through detection, the barium hexaboride aqueous dispersion obtained in the embodiment of the invention is black, the solid content is 0.5wt%, and the barium hexaboride aqueous dispersion is sealed and kept stand for 12 months without sedimentation; the barium hexaboride alcohol phase dispersoid obtained in the embodiment of the invention is black, has the solid content of 0.5wt%, and does not settle after being sealed and kept stand for 12 months.
Comparative example 1
This comparative example differs from example 1 only in that: after the washing operation, the drying is carried out, and then the subsequent operation is carried out. The same as in example 1.
Through detection, the lanthanum hexaboride aqueous dispersion obtained in the comparative example is black, the solid content is 5wt%, and settlement occurs after sealing and standing for 0.5 days.
Application examples 1 to 3 of rare earth hexaboride liquid phase dispersion
The lanthanum hexaboride aqueous phase dispersoid and the ionic liquid phase dispersoid obtained in the embodiment 1 are applied to preparing transparent heat-insulating coating;
the cerium hexaboride aqueous phase dispersion and the ionic liquid phase dispersion obtained in the embodiment 2 of the invention are applied to the preparation of solar photo-thermal conversion nanofluid;
the lanthanum hexaboride aqueous phase dispersoid and the alcohol phase dispersoid obtained in the embodiment 3 are applied to the preparation of seawater desalination devices.
Application example 4 of alkaline earth hexaboride liquid phase dispersion
The barium hexaboride aqueous phase dispersoid and the alcohol phase dispersoid obtained in the embodiment 4 are applied to preparing the transparent heat-insulating coating.
Claims (9)
1. A method for preparing a rare earth or alkaline earth hexaboride liquid phase dispersion, characterized by comprising the steps of:
(1) uniformly mixing rare earth salt or alkaline earth salt and a boron source, heating to react under vacuum or inert atmosphere, and cooling to room temperature to obtain a primary product;
(2) emulsifying the primary product obtained in the step (1) in water, carrying out ultrasonic oscillation, filtering or centrifuging, washing with water, adding an alkaline aqueous solution into the washing product, emulsifying, and carrying out ultrasonic oscillation to obtain a rare earth or alkaline earth hexaboride aqueous phase dispersoid; or after the washing product is alcohol washed to remove water, adding an organic solvent, emulsifying, and ultrasonically oscillating to obtain the rare earth or alkaline earth hexaboride organic phase dispersion.
2. The method of preparing a liquid dispersion of a rare earth or alkaline earth hexaboride according to claim 1, characterized in that: in the step (1), the molar ratio of the rare earth element in the rare earth salt or the alkaline earth element in the alkaline earth salt to the boron element in the boron source is 1: 2-12; the rare earth salt is one or more of rare earth chloride, rare earth oxychloride, rare earth fluoride or rare earth bromide; the alkaline earth salt is one or more of chlorinated alkaline earth, chlorine oxidized alkaline earth, fluorinated alkaline earth or brominated alkaline earth; the boron source is an alkali metal borohydride; the alkali metal borohydride is NaBH4、KBH4Or LiBH4One or more of them.
3. The process for the preparation of a liquid dispersion of a rare earth or alkaline earth hexaboride according to claim 1 or 2, characterized in that: in the step (1), the vacuum degree of the vacuum is 0-100 Pa; the inert atmosphere is argon and/or helium.
4. A method for preparing a liquid-phase dispersion of a rare earth or alkaline earth hexaboride according to any one of claims 1 to 3, characterized in that: in the step (1), the specific operation of the heating reaction is as follows: heating to 300-400 ℃ at the speed of 5-20 ℃/min, preserving heat for 1-5 h, heating to 400-1200 ℃ at the speed of 1-30 ℃/min, and preserving heat for 1-10 h; the cooling is carried out at a rate of 5-40 ℃/min to room temperature.
5. The method for producing a liquid-phase dispersion of a rare earth or alkaline earth hexaboride according to any one of claims 1 to 4, characterized in that: in the step (1), adding a low-melting-point medium which is 1-20 times of the total mass of the rare earth salt or the alkaline earth salt and a boron source; the low-melting-point medium is low-melting-point elemental metal or low-melting-point molten salt; the low-melting-point elementary metal is one or more of elementary Sn, elementary In or elementary Bi; the low-melting-point molten salt is LiCl, KCl, NaCl or ZnCl2One or more of。
6. The method for producing a liquid-phase dispersion of a rare earth or alkaline earth hexaboride according to any one of claims 1 to 5, characterized in that: in the step (2), the volume-to-mass ratio of the water to the total mass of the raw materials in the step (1) is 3-10: 1; the power of the emulsification treatment is 0.5-40 kW, the rotating speed is 1000-30000 r/min, and the time of each emulsification treatment is 20-40 min; the frequency of the ultrasonic oscillation is 10-50 kHz, and the time of each ultrasonic oscillation is 10-180 min; the temperature of the water washing is 10-80 ℃; the emulsification treatment, the ultrasonic oscillation, the filtration or the centrifugation and the water washing are repeatedly carried out for more than or equal to 3 times, and AgNO is dripped into the water washing liquid3Or Ca (OH)2The solution was free of white precipitate.
7. The process for the preparation of a liquid dispersion of a rare earth or alkaline earth hexaboride according to claim 5 or 6, characterized in that: in the step (2), when the low-melting-point medium is low-melting-point elemental metal, after the first emulsification treatment and ultrasonic oscillation, the pH value is adjusted to 9-10 by using an alkaline aqueous solution, the mixture is kept stand, the low-melting-point elemental metal is separated, then filtration or centrifugation is carried out, water washing is carried out, the emulsification treatment, the ultrasonic oscillation and the filtration or the centrifugation are repeated, the water washing operation is not less than 2 times, AgNO is dripped into the water washing liquid3Or Ca (OH)2Until the solution has no white precipitate; the pH value of the alkaline aqueous solution for adjusting the pH value is more than or equal to 10; the alkaline aqueous solution is a sodium hydroxide aqueous solution or an ammonia aqueous solution; the standing time is 5-30 h.
8. The method for producing a liquid-phase dispersion of a rare earth or alkaline earth hexaboride according to any one of claims 1 to 7, characterized in that: in the step (2), the volume mass ratio of the alkaline aqueous solution or the organic solvent to the dry weight of the water washing product is 5-1000: 1; the pH value of the alkaline aqueous solution is 9-10; the alkaline aqueous solution is a sodium hydroxide aqueous solution or an ammonia aqueous solution; the number of times of water removal by alcohol washing is more than or equal to 2; the organic solvent is one or more of alcoholic solution, ionic liquid, grease or liquid resin; the alcohol used for washing the water by the alcohol and the alcohol solution are one or more of ethanol, glycol or n-butanol; the ionic liquid is 1-hexyl-3-methylimidazole bistrifluoromethanesulfonimide salt and/or 1-butyl-3-methylimidazole tetrafluoroborate.
9. Use of a liquid dispersion of a rare earth or alkaline earth hexaboride compound obtained by the preparation method according to any one of claims 1 to 8, wherein: the rare earth or alkaline earth hexaboride liquid-phase dispersion obtained by the preparation method of any one of claims 1 to 8 is applied to the preparation of transparent heat-insulating coatings, solar photo-thermal conversion nanofluids and seawater desalination devices.
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102050457A (en) * | 2009-10-29 | 2011-05-11 | 苏玉长 | Synthesis method of nano rare-earth tetraboride and applications thereof |
| CN106395843A (en) * | 2016-09-09 | 2017-02-15 | 中国人民解放军国防科学技术大学 | Preparation method of lanthanum hexaboride nanometer powder and application of lanthanum hexaboride nanometer powder |
| JP2017145164A (en) * | 2016-02-16 | 2017-08-24 | 住友金属鉱山株式会社 | Boride particles, boride particle production method, and boride particle dispersion |
| CN110520500A (en) * | 2017-02-28 | 2019-11-29 | 住友金属矿山株式会社 | Hot radiation shielding particle, hot radiation shielding particle dispersion liquid, hot radiation shielding film coating fluid and the hot radiation shielding film, hot radiation shielding resin film, hot radiation shielding microparticle dispersion that have used them |
-
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- 2020-11-10 CN CN202011247903.1A patent/CN114455599B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102050457A (en) * | 2009-10-29 | 2011-05-11 | 苏玉长 | Synthesis method of nano rare-earth tetraboride and applications thereof |
| JP2017145164A (en) * | 2016-02-16 | 2017-08-24 | 住友金属鉱山株式会社 | Boride particles, boride particle production method, and boride particle dispersion |
| CN106395843A (en) * | 2016-09-09 | 2017-02-15 | 中国人民解放军国防科学技术大学 | Preparation method of lanthanum hexaboride nanometer powder and application of lanthanum hexaboride nanometer powder |
| CN110520500A (en) * | 2017-02-28 | 2019-11-29 | 住友金属矿山株式会社 | Hot radiation shielding particle, hot radiation shielding particle dispersion liquid, hot radiation shielding film coating fluid and the hot radiation shielding film, hot radiation shielding resin film, hot radiation shielding microparticle dispersion that have used them |
Non-Patent Citations (1)
| Title |
|---|
| 张小琴等: "稀土元素硼化物的研究进展" * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115180632A (en) * | 2022-07-15 | 2022-10-14 | 贵州交通职业技术学院 | Morphology-controllable preparation method and application of rare earth hexaboride nano powder |
| CN115180632B (en) * | 2022-07-15 | 2023-11-14 | 贵州交通职业技术学院 | Controllable preparation method and application of morphology of rare earth hexaboride nano powder |
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