A method for preparing zinc selenide powder

Abstract

The application belongs to the field of inorganic compound preparation, and particularly relates to a preparation method of zinc selenide powder. The preparation method uses zinc powder and selenium powder as raw materials, mixes the raw materials, and then adds a medium solution to perform a solvothermal reaction. Under the presence of the medium solution and at a certain temperature, the zinc powder and the selenium powder directly combine to generate zinc selenide. After the reaction, solid-liquid separation is performed, the obtained solid is washed and vacuum dried, and then the zinc selenide powder with a purity of more than 99.9% is obtained. The method has the advantages of a short process and simple operation. The zinc selenide is directly obtained through liquid-phase reaction by using zinc and selenium as raw materials. The raw material utilization rate is high, and the cost is low. The raw material conversion rate calculated based on zinc is more than 95%, the reaction condition is mild, the medium solution can be recycled, and the cost is low.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of inorganic compound preparation, and particularly relates to a preparation method of zinc selenide powder. BACKGROUND

[0002] Selenium has a wide range of applications and can be applied to metallurgy, glass, ceramics, electronics, solar energy, feed and many other fields. Among them, the main one with a large amount in the high-end market is negative divalent selenium, such as hydrogen selenide used in the semiconductor industry, zinc selenide used as an infrared optical material, and selenium carrageenan used in the medical food industry.

[0003] At present, the main source of negative divalent selenium in industry is hydrogen selenide. There are mainly two methods for preparing hydrogen selenide in industry. One is hydrogen reduction method, which is to directly combine selenium and hydrogen at high temperature to obtain hydrogen selenide. The other is zinc selenide acidification method, which is to react zinc selenide powder with inorganic acid to release hydrogen selenide. The hydrogen reduction method has a relatively fast reaction, but the yield is low, only about 50%, and the subsequent separation process is complex, the equipment requirement is high, and the large-scale promotion in industry is limited. The zinc selenide acidification method is simple to operate, can be flexibly implemented, has a relatively low safety protection level, and has a wider application scenario, but needs cheap zinc selenide powder raw material, otherwise the cost is high.

[0004] For the method for preparing zinc selenide powder, one is to pass hydrogen selenide into a zinc salt solution to react and produce, but this method needs to use toxic hydrogen selenide, and the cost of the way of using hydrogen selenide to prepare zinc selenide and then acidifying to prepare hydrogen selenide is also high. One is to use zinc and selenium to combine at high temperature, such as CN03134430.5, which mixes elemental selenium powder and elemental zinc powder, places them in a vacuum chamber, heats to 300-380 DEG C to generate a primary reactant, then grinds the primary reactant, places it in a crucible, and anneals at 550-700 DEG C under vacuum conditions to obtain zinc selenide (ZnSe) powder with high purity. There is also a method for preparing zinc selenide by high-temperature reaction of zinc salt and selenium powder, such as CN202111198975.6, which first mixes a zinc chloride solution and an oxalic acid solution to obtain zinc oxalate, then mixes the zinc oxalate with selenium powder, and reacts at 300-350 DEG C to obtain zinc selenide powder. Although these existing methods can prepare zinc selenide powder, they all have problems of long process, complex operation, low utilization rate of raw materials, and high preparation cost. SUMMARY

[0005] The application discloses a preparation method of zinc selenide powder to solve any of the above and other potential problems in the prior art.

[0006] To achieve the above object, the technical scheme of the present application is: a preparation method of zinc selenide powder, which uses zinc powder and selenium powder as raw materials, mixes them, and then adds a medium solution to perform a solvothermal reaction under heating to dissolve the selenium powder in the medium solution to generate soluble selenium salt and water, and then the soluble selenium salt and water react with the zinc powder to generate zinc selenide, which is subjected to solid-liquid separation, and the obtained solid is washed and vacuum dried to obtain the zinc selenide powder with a purity of more than 99.9%.

[0007] Further, the specific steps of the preparation method are:

[0008] S1) zinc powder and selenium powder are mixed according to a certain proportion, and then added to a medium solution to stir uniformly to obtain a mixed solution;

[0009] S2) the mixed solution obtained in S1) is loaded into a reaction kettle, stirring is started, and heating is performed to a certain temperature, and then the temperature is kept constant, heating is stopped, and the solid-liquid separation of the reaction material is performed, and the liquid is reserved for later use;

[0010] S3) the solid obtained in S2) is mixed with an alkaline solution to perform washing, and then the solid-liquid separation of the washed material is performed, the washing water is sent to waste water treatment, and the washing residue is vacuum dried to obtain the zinc selenide powder.

[0011] Further, the liquid in S2) is recycled as the medium solution.

[0012] Further, the molar ratio between the zinc powder and the selenium powder in S1) is 0.9:1.0.

[0013] The solid and the medium solution are mixed according to a mass-volume ratio of 1:3-1:10, and the mass of the solid refers to the total amount of the zinc powder and the selenium powder.

[0014] Further, the medium solution includes a solute and a solvent.

[0015] The solute is sodium hydroxide, ammonia water and an additive, and the solvent is one or a combination of several of water, ethanol, acetone and cyclohexane.

[0016] Further, the amount of sodium hydroxide added is 20%-100% of the mass of the zinc powder, and the amount of ammonia water added is 40%-80% of the mass of the zinc powder, and the ammonia content in the ammonia water is 25%.

[0017] The additive is one or a combination of several of sodium lignosulfonate, sodium tripolyphosphate and hydroxyethyl cellulose.

[0018] The additive is added according to 0.1%-5% of the mass of the zinc powder.

[0019] Further, the temperature in S2) is 120-200℃, and the holding time is 3-12h.

[0020] Further, the solid in S3) is mixed with the alkaline solution at a mass-volume ratio of 1:2, the washing temperature is 40-90°C, and the washing time is 0.5-3.0 h.

[0021] Further, the alkaline solution is a sodium hydroxide solution with a concentration of 0.1-1.0 mol / L.

[0022] Further, the raw material conversion rate in the preparation method is above 95%, and the purity of the obtained powdered zinc selenide product is above 99.9%.

[0023] The present application has the following beneficial effects and outstanding advantages:

[0024] 1) The process is short and simple, and zinc selenide is directly obtained by liquid-phase reaction using zinc and selenium as raw materials; the raw material utilization rate is high, and the cost is low; the raw material conversion rate calculated based on zinc is above 95%; the reaction conditions are mild; the medium solution can be recycled; and the cost is low.

[0025] 2) The present application can achieve the above beneficial effects and outstanding advantages, and the key lies in the innovative configuration of the medium solution required for the reaction, wherein the solute in the medium solution comprises sodium hydroxide, ammonia water and an additive, and their functions are as follows:

[0026] ① The function of sodium hydroxide is to obtain soluble selenium salt. At a certain temperature, selenium powder reacts with sodium hydroxide to generate soluble selenium salt, which has strong activity and fast mass transfer, and is an intermediate in the reaction.

[0027] ② The function of ammonia water is to complex zinc hydroxide. At a certain temperature, zinc powder reacts with water to generate active hydrogen and zinc hydroxide, the active hydrogen reacts with the soluble selenium salt to obtain selenium ions and generate water, and the zinc hydroxide reacts with ammonia water to obtain zinc-ammonia ions, which react with the selenium ions to obtain zinc selenide. If ammonia water is not added, the zinc hydroxide does not change and exists in the form of solid, the reaction activity of the solid zinc hydroxide with the selenium ions is weak, and the solid zinc hydroxide easily wraps the generated zinc selenide.

[0028] ③ The function of the additive is to prevent the melting of selenium powder into a group. At a certain temperature, the selenium powder melts and forms a group, the reaction activity of the selenium group is weak, and the selenium group easily wraps the generated zinc selenide. However, when the additive exists, the melted selenium powder can be uniformly dispersed in the medium, the reaction activity is improved, and the zinc selenide is not wrapped. In the reaction process, if solid wrapping occurs, the generation rate and purity of the zinc selenide will be significantly reduced. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 The figure is a flowchart of the preparation method of the zinc selenide powder.

[0030] Figure 2SEM image of the zinc selenide powder obtained by the preparation method of the present application in Example 1.

[0031] Figure 3 XRD pattern of the zinc selenide powder obtained by the preparation method of the present application in Example 1. DETAILED DESCRIPTION

[0032] The technical solutions of the present application in the embodiments will be described in detail below. Obviously, the described embodiments are only a part of the embodiments of the present application, and are not all the embodiments. Based on the embodiments of the present application, all other embodiments obtained by other persons within the scope of the art without making creative efforts belong to the protection scope of the present application.

[0033] The present application is a preparation method of zinc selenide powder. The preparation method uses zinc powder and selenium powder as raw materials, mixes them, and then adds a medium solution to perform a solvothermal reaction under heating, so that the selenium powder in the medium solution is dissolved to generate a soluble selenium salt and water. The soluble selenium salt and water react with the zinc powder to generate zinc selenide. Solid-liquid separation is performed, and the obtained solid is washed and vacuum dried to obtain a powder-like zinc selenide with a purity of 99.9% or above.

[0034] The specific steps of the preparation method are as follows:

[0035] S1) zinc powder and selenium powder are mixed in a certain proportion, and then added to a medium solution to stir uniformly to obtain a mixed solution;

[0036] S2) the mixed solution obtained in S1) is loaded into a reaction kettle, stirring is started, and heating is performed to a certain temperature, and then the heating is stopped after keeping the temperature. The solid-liquid separation is performed on the reaction material, and the liquid is reserved for later use;

[0037] S3) the solid obtained in S2) is mixed with an alkaline solution for washing. After washing, the solid-liquid separation is performed on the material, the washing water is sent to wastewater treatment, and the washing residue is vacuum dried to obtain a powder-like zinc selenide, as shown in Figure 1

[0038] The liquid in S2) is recycled as a medium solution.

[0039] The molar ratio of the zinc powder and the selenium powder in S1) is 0.9:1.0.

[0040] The mixture material and the medium solution are mixed in a mass-volume ratio of 1:3 to 1:10. The mixture material refers to the total amount of zinc powder and selenium powder.

[0041] The medium solution includes a solute and a solvent.

[0042] The solute is sodium hydroxide, ammonia water and an additive, and the solvent is one or a combination of several of water, ethanol, acetone and cyclohexane.​

[0043] The amount of sodium hydroxide added is 20% to 100% of the mass of the zinc powder, and the amount of ammonia water added is 40% to 80% of the mass of the zinc powder, and the ammonia content in the ammonia water is 25%;

[0044] The additive is one or a combination of several of sodium lignin sulfonate, sodium tripolyphosphate, and hydroxyethyl cellulose;

[0045] The additive is added in an amount of 0.1% to 5% of the mass of the zinc powder.

[0046] The temperature in S2) is 120 to 200°C, and the holding time is 3 to 12 h.

[0047] The solid and the alkaline solution in S3) are mixed in a mass-to-volume ratio of 1:2, the washing temperature is 40 to 90°C, and the washing time is 0.5 to 3.0 h.

[0048] The alkaline solution is a sodium hydroxide solution with a concentration of 0.1 to 1.0 mol / L.

[0049] The raw material conversion rate in the preparation method is above 95%, and the purity of the obtained powdered zinc selenide product is above 99.9%.

[0050] Example 1

[0051] 100 g of zinc powder and 134 g of selenium powder were added to 1.2 L of an aqueous solution containing 40 g / L of sodium hydroxide, 31 g / L of ammonia water, and 1.1 g / L of sodium lignin sulfonate, and the mixed material was loaded into a reaction kettle, stirring and heating were started, and when the temperature reached 160°C, the heating was stopped after holding for 2 h. The reaction material was then solid-liquid separated, the liquid was reserved for later use, the solid was mixed with 0.5 L of a 20 g / L sodium hydroxide solution, and the mixture was stirred at 50°C for 1 h. The washed material was then solid-liquid separated, the washing water was sent for waste water treatment, and the washed residue was vacuum dried to obtain the product. The content of zinc selenide in the product was 99.92%, and the weight was 212 g. The SEM image and XRD spectrum of the prepared zinc selenide powder are shown in Figure 2 and Figure 3 .

[0052] Example 2

[0053] Take 100 g of zinc powder and 134 g of selenium powder, add to 1.5 L of ethanol solution containing 60 g / L of sodium hydroxide, 52 g / L of ammonia water and 0.9 g / L of sodium tripolyphosphate, load the mixed material into the reaction kettle, start stirring and heating, keep at 120℃ for 5h, stop heating, solid-liquid separation of the reaction material, the liquid is reserved for later use, the solid is mixed with 1.0 L of 30 g / L sodium hydroxide solution, stirred at 60℃ for 1.5h, solid-liquid separation of the washed material, the washing water is sent to wastewater treatment, and the washed residue is vacuum dried to obtain the product, the content of zinc selenide in the product is 99.93%, and the weight is 221 g.

[0054] Example 3

[0055] Take 100 g of zinc powder and 134 g of selenium powder, add to 2.0 L of aqueous solution containing 20 g / L of sodium hydroxide, 43 g / L of ammonia water and 1.5 g / L of hydroxyethyl cellulose, load the mixed material into the reaction kettle, start stirring and heating, keep at 180℃ for 3h, stop heating, solid-liquid separation of the reaction material, the liquid is reserved for later use, the solid is mixed with 0.6 L of 25 g / L sodium hydroxide solution, stirred at 70℃ for 2h, solid-liquid separation of the washed material, the washing water is sent to wastewater treatment, and the washed residue is vacuum dried to obtain the product, the content of zinc selenide in the product is 99.95%, and the weight is 210 g.

[0056] Example 4

[0057] Take 100 g of zinc powder and 134 g of selenium powder, add to the liquid reserved for later use in Example 2, load the mixed material into the reaction kettle, start stirring and heating, keep at 160℃ for 2h, stop heating, solid-liquid separation of the reaction material, the liquid is reserved for later use, the solid is mixed with 0.5 L of 20 g / L sodium hydroxide solution, stirred at 50℃ for 1h, solid-liquid separation of the washed material, the washing water is sent to wastewater treatment, and the washed residue is vacuum dried to obtain the product, the content of zinc selenide in the product is 99.90%, and the weight is 209 g.

[0058] The above describes a method for preparing a zinc selenide powder provided by the embodiments of the present application. The above description of the embodiments is only used to help understand the method and its core idea; at the same time, for those skilled in the art, according to the idea of the present application, the specific implementation and application range will be changed, and the above description should not be understood as a limitation of the present application.

[0059] As used in the specification and claims, certain terms have particular meanings. One skilled in the art will understand that different manufacturers can refer to a component by different names. The specification and claims should not be construed as limited to components by a particular name, but should be construed by the component's function. As used in the specification and claims, "comprising" and "including" are meant to be interpreted as specifying open-ended claims that are not limited to the listed elements. "Approximately" means within an acceptable error range for the corresponding function, which will vary from one context to another. The description that follows is intended to provide a better understanding of the preferred embodiments of the present application, and is not intended to provide an exhaustive description of the application. The description serves only to illustrate the general principles of the application, and is not intended to limit the present application to specific embodiments. The scope of the present application is to be limited only by the claims that follow.

[0060] It should also be noted that the terms "comprising," "including," and "having" or any other variation thereof, are intended to cover a non-exclusive inclusion. For example, a process, product, or composition that comprises a list of elements is not necessarily limited to only those elements but can include other elements not expressly listed or inherent to such process, product, or composition. An element proceeded by "comprises... a" does not, without more constraints, exclude the existence of additional identical elements in the process, product, or composition that contains the element.

[0061] It should be understood that the term "and / or" as used herein is merely an open-ended descriptive term indicating that three conditions exist, for example, A and / or B can mean: A exists alone, A and B exist together, and B exists alone. In addition, the character " / " as used herein generally represents an "or" relationship between the front and rear associated objects.

[0062] The above specification and description of the application discloses and describes several preferred embodiments of the application, but as previously noted, it is not intended to limit the application to the forms disclosed. Rather, it is intended to cover all modifications, equivalents, and alternatives falling within the scope of the application as defined by the following claims.

Claims

1. A method for preparing zinc selenide powder, characterized in that: The preparation method uses zinc powder and selenium powder as raw materials, mixes them, and then adds a medium solution to heat and perform a solvothermal reaction, so that the selenium powder in the medium solution is dissolved to generate a soluble selenium salt and water, the soluble selenium salt and water react with the zinc powder to generate zinc selenide, solid-liquid separation is performed, the obtained solid is washed and vacuum dried, and then powder-like zinc selenide with a purity of 99.9% or above is obtained; the specific steps of the preparation method are as follows: S1) zinc powder and selenium powder are mixed according to a certain ratio, the mixture is added to a medium solution and stirred uniformly to obtain a mixed solution; The molar ratio of the zinc powder and the selenium powder is 0.9:1.0; the mass-volume ratio of the mixed powder to the medium solution is 1:3-1:10; The medium solution includes a solute and a solvent; The solute is sodium hydroxide, ammonia water and an additive, and the solvent is water, ethanol, acetone and cyclohexane alone or a combination of one or more thereof; The amount of sodium hydroxide added is 20%-100% of the mass of the zinc powder, and the amount of ammonia water added is 40%-80% of the mass of the zinc powder; The additive is one or a combination of one or more of sodium lignosulfonate, sodium tripolyphosphate and hydroxyethyl cellulose; The additive is added in an amount of 0.1%-5% of the mass of the zinc powder; S2) the mixed solution obtained in S1) is loaded into a reaction kettle, stirring is started, and heating is performed to a certain temperature, the temperature is maintained, heating is stopped, solid-liquid separation is performed on the post-reaction material, and the liquid is reserved for later use; The temperature is 120-200℃, and the holding time is 3-12h; S3) the solid obtained in S2) is mixed with an alkaline solution for washing, solid-liquid separation is performed on the post-washing material, the washing water is sent to wastewater treatment, and the washing residue is vacuum dried to obtain powder-like zinc selenide; The solid and the alkaline solution are mixed in a mass-volume ratio of 1:2, the washing temperature is 40-90℃, and the washing time is 0.5-3.0h.

2. The production method according to claim 1, characterized by, The liquid in S2) is recycled as the medium solution.

3. The preparation method according to claim 1, characterized in that The alkaline solution is a sodium hydroxide solution with a concentration of 0.1-1.0mol / L.

4. The method of claim 1, wherein, The raw material conversion rate in the preparation method is 95% or above.

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