Preparation method of indium methanesulfonate solution

Abstract

The invention discloses a preparation method of an indium methanesulfonate solution, which comprises the following steps: preparing metal indium strips into metal indium scraps with high specific surface area, then synthesizing the metal indium scraps with high specific surface area and methanesulfonic acid into an indium methanesulfonate reaction feed liquid, and filtering, concentrating, crystallizing and centrifugally separating the indium methanesulfonate reaction feed liquid to obtain indium methanesulfonate crystals. Finally, the indium methanesulfonate crystals are added into deionized water to be prepared into the indium methanesulfonate solution with the indium ion content of 120-200 g / L and the free methanesulfonic acid content of 30-50 g / L. The technical blank of preparing the indium methanesulfonate solution in China can be filled up, and the prepared indium methanesulfonate solution is high in purity, good in quality and high in indium recovery rate; the method can be widely applied to the fields of thin-film solar cells, semiconductor wafer metal substrates, electronic circuit board special welding layers and the like, and is low in production cost and wide in market prospect.

Description

Technical Field

[0001] The invention relates to a method for preparing an indium methanesulfonate solution. Background Art

[0002] Indium is a silver-grey, extremely soft, fusible metal with extremely low content and high dispersion in the earth's crust. It is a rare metal. Indium has the characteristics of low melting point, corrosion resistance, good reflectivity, strong plasticity and ductility. It is called the "vitamin of alloys" and is widely used in industries such as liquid crystal displays, flat panels, electronic semiconductors, and solar photovoltaic cells. Taiwan Patent TW201804023A provides an indium electroplating composition and a preparation method thereof. The indium electroplating composition provided can be used on semiconductor wafers and their substrate metal layers to improve the performance and reliability of semiconductor devices, which is of great significance to the semiconductor industry. However, there are few literature reports on how the indium methanesulfonate used in this patent is prepared. Only one paper published by Belgian scholar KU Leuven in the 42nd issue of "Physical Chemistry and Physics" in 2020 mentioned that indium methanesulfonate can be synthesized from indium oxide and methanesulfonic acid. At present, there are no manufacturers of indium methanesulfonate in China. At present, the indium methanesulfonate used in the electroplating industry must be imported from abroad, which has problems such as high prices and long order cycles. Summary of the invention

[0003] In order to solve the above problems, the present invention provides a method for preparing an indium methanesulfonate solution, comprising the following steps: Preparation of high specific surface area metal indium debris: wash the surface of a metal indium bar with an indium content greater than 99.99% with deionized water, dry it, put it into a stainless steel pot, heat it to 160-180°C, melt the solid metal indium bar into liquid metal indium, pour the liquid metal indium into a container filled with 0-20°C deionized water in batches, and the metal indium liquid explodes into high specific surface area metal indium debris when cooled, and fish it out and dry it for later use; Synthesis of indium methanesulfonate: Add high specific surface area metal indium debris into a reactor, add a methanesulfonic acid solution with a mass concentration of 35-80%, and heat to 105-130°C. Too high a temperature will cause the metal indium debris to melt and agglomerate, reducing the reaction rate. Keep the temperature to react and synthesize indium methanesulfonate. Cool the reaction kettle until the density of the indium methanesulfonate solution is 1.55-1.6 g / ml, and transfer the indium methanesulfonate reaction solution. The method for preparing a methanesulfonic acid solution is common knowledge. A methanesulfonic acid solution can be obtained by adding a certain mass of pure methanesulfonic acid to a certain volume of water and stirring, which will not be described in detail. Preparation of low-free-acid indium methanesulfonate crystals: filtering the indium methanesulfonate reaction solution to obtain the filtrate, concentrating the filtrate, cooling and crystallizing, and centrifuging to obtain low-free-acid indium methanesulfonate crystals; Preparation of indium methanesulfonate solution: Slowly add low-free acid indium methanesulfonate crystals into pre-prepared deionized water while stirring to prepare an indium methanesulfonate solution with an indium ion content of 120-200 g / L and free methanesulfonic acid of 30-50 g / L.

[0004] Preferably, in the process of preparing the high specific surface area metal indium chips, the melted liquid metal indium is poured into deionized water for cooling according to a volume ratio of 1:2-6.

[0005] Preferably, the mass concentration of methanesulfonic acid during the synthesis of indium methanesulfonate is 70%.

[0006] Preferably, during the synthesis of indium methanesulfonate, high specific surface area metal indium chips and methanesulfonic acid are added according to a solid-liquid ratio of 1 g: 1.0-1.6 ml.

[0007] Preferably, the temperature is maintained at 120° C. during the synthesis of indium methanesulfonate.

[0008] Preferably, in the process of preparing low free acid indium methanesulfonate crystals, vacuum decompression is used to concentrate until the soluble solid content is 55-65%, and then cooling and crystallizing, wherein the vacuum degree is 30-60 mbar.

[0009] Preferably, in the process of preparing low-free acid indium methanesulfonate crystals, a centrifuge is used for separation, and the centrifuge speed is 2000-4000 rpm.

[0010] Preferably, the separation time of the centrifuge is 10 to 15 minutes.

[0011] Preferably, during the preparation of the indium methanesulfonate solution, the stirring speed is 200-400 r / min.

[0012] The beneficial effect is that: the application prepares metal indium bars into metal indium scraps with high specific surface area, then synthesizes indium methanesulfonate reaction solution with the metal indium scraps with high specific surface area and methanesulfonic acid, obtains indium methanesulfonate crystals by filtering, concentrating, crystallizing and centrifuging the indium methanesulfonate reaction solution, and finally adds the indium methanesulfonate crystals into deionized water to prepare an indium methanesulfonate solution with an indium ion content of 120-200 g / L and free methanesulfonic acid of 30-50 g / L, which can fill the technical gap of preparing indium methanesulfonate solution in China. The prepared indium methanesulfonate solution has high purity, good quality and high indium recovery rate, can be widely used in thin-film solar cells, metal substrates of semiconductor wafers, special welding layers of electronic circuit boards and other fields, has low production cost and great market prospects. DETAILED DESCRIPTION

[0013] The present invention is further described in detail below in conjunction with specific embodiments so that those skilled in the art can understand the present invention more clearly.

[0014] The following embodiments are only used to illustrate the present invention, but are not limited to the scope of the present invention. Based on the specific embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without creative work belong to the protection scope of the present invention.

[0015] In the examples of the present invention, unless otherwise specified, all raw material components are commercially available products well known to those skilled in the art; in the examples of the present invention, unless otherwise specified, the technical means used are conventional means well known to those skilled in the art.

[0016] Source of raw materials: Metal indium bars with an indium content greater than 99.99% were purchased from Changsha Youcheng Metal Materials Co., Ltd. Methanesulfonic acid was purchased from Guangdong Wengjiang Chemical Reagent Co., Ltd.; The remaining reagents are commercially available.

[0017] Example 1 This embodiment provides a method for preparing an indium methanesulfonate solution, comprising the following steps: Preparation of high specific surface area metal indium chips: wash the surface of a metal indium bar with an indium content greater than 99.99% with deionized water, dry it, put it into a stainless steel pot, heat it to 170°C, melt the solid metal indium bar into liquid metal indium, and quickly pour the liquid metal indium into a container filled with 0°C deionized water in batches according to a volume ratio of 1:4. The metal indium liquid explodes into high specific surface area metal indium chips when cooled, and the chips are fished out and dried for later use; Synthesis of indium methanesulfonate: adding high specific surface area metal indium chips and methanesulfonic acid solution with a mass concentration of 70% to a reactor at a solid-liquid ratio of 1g:1.3ml, heating to 120°C, keeping the temperature to react and synthesize indium methanesulfonate, cooling to room temperature, measuring the density of the indium methanesulfonate liquid in the reactor to be 1.58g / ml, and transferring the indium methanesulfonate reaction liquid; Preparation of low-free acid indium methanesulfonate crystals: filtering the indium methanesulfonate reaction liquid to obtain the filtrate, concentrating the filtrate under vacuum decompression to a soluble solid content of 55-65%, and then cooling and crystallizing, wherein the vacuum degree is 50 mbar, and centrifuging to obtain low-free acid indium methanesulfonate crystals by centrifugation, the centrifuge speed is 3000 rpm, and the separation time is 12 minutes; Preparation of indium methanesulfonate solution: Low free acid indium methanesulfonate crystals were slowly added to pre-prepared deionized water while stirring at a stirring speed of 300 r / min to prepare an indium methanesulfonate solution with an indium ion content of 160 g / L and free methanesulfonic acid of 40 g / L.

[0018] Example 2 This embodiment provides a method for preparing an indium methanesulfonate solution, comprising the following steps: Preparation of high specific surface area metal indium chips: wash the surface of a metal indium bar with an indium content greater than 99.99% with deionized water, dry it, put it into a stainless steel pot, heat it to 180°C, melt the solid metal indium bar into liquid metal indium, pour the liquid metal indium into a container filled with 10°C deionized water in batches according to a volume ratio of 1:6, and the metal indium liquid explodes into high specific surface area metal indium chips when cooled, which are fished out and dried for later use; Synthesis of indium methanesulfonate: adding high specific surface area metal indium chips and 80% mass concentration of methanesulfonic acid solution to a reactor at a solid-liquid ratio of 1g:1.6ml, heating to 130°C, keeping the temperature to react and synthesize indium methanesulfonate, cooling to room temperature, measuring the density of the indium methanesulfonate liquid in the reactor to be 1.55g / ml, and transferring the indium methanesulfonate reaction liquid; Preparation of low-free acid indium methanesulfonate crystals: filtering the indium methanesulfonate reaction liquid to obtain the filtrate, concentrating the filtrate under vacuum decompression to a soluble solid content of 55-65%, and then cooling and crystallizing, wherein the vacuum degree is 60 mbar, and centrifuging to obtain low-free acid indium methanesulfonate crystals by centrifugation, the centrifuge speed is 4000 rpm, and the separation time is 10 min; Preparation of indium methanesulfonate solution: Low free acid indium methanesulfonate crystals were slowly added to pre-prepared deionized water while stirring at a stirring speed of 200 r / min to prepare an indium methanesulfonate solution with an indium ion content of 200 g / L and free methanesulfonic acid of 50 g / L.

[0019] Example 3 This embodiment provides a method for preparing an indium methanesulfonate solution, comprising the following steps: Preparation of high specific surface area metal indium chips: wash the surface of a metal indium bar with an indium content greater than 99.99% with deionized water, dry it, put it into a stainless steel pot, heat it to 160°C, melt the solid metal indium bar into liquid metal indium, pour the liquid metal indium into a container filled with 20°C deionized water in batches according to a volume ratio of 1:2, and the metal indium liquid explodes into high specific surface area metal indium chips when cooled, and fish it out and dry it for later use; Synthesis of indium methanesulfonate: adding high specific surface area metal indium chips and 35% mass concentration of methanesulfonic acid solution into a reactor at a solid-liquid ratio of 1g:1ml, heating to 105°C, keeping the temperature to react and synthesize indium methanesulfonate, cooling to room temperature, measuring the density of the indium methanesulfonate liquid in the reactor to be 1.6g / ml, and transferring the indium methanesulfonate reaction liquid; Preparation of low-free-acid indium methanesulfonate crystals: filtering the indium methanesulfonate reaction liquid to obtain the filtrate, concentrating the filtrate under vacuum decompression to a soluble solid content of 55-65%, and then cooling and crystallizing, wherein the vacuum degree is 30 mbar, and centrifuging to obtain low-free-acid indium methanesulfonate crystals by centrifugation, the centrifuge speed is 2000 rpm, the separation time is 15 minutes, and centrifugation to obtain low-free-acid indium methanesulfonate crystals; Preparation of indium methanesulfonate solution: Low free acid indium methanesulfonate crystals were slowly added to pre-prepared deionized water while stirring at a stirring speed of 400 r / min to prepare an indium methanesulfonate solution with an indium ion content of 120 g / L and free methanesulfonic acid of 30 g / L.

[0020] The indium methanesulfonate solutions prepared in Examples 1 to 3 were tested.

[0021] Test Method Indium (In) concentration detection is in accordance with YS / T 276.9-2011 "Indium Chemical Analysis Method Part 9: Determination of Indium Content Na 2 EDTA titration method; Free acid (CH 3 SO 3 The concentration of H was determined by the method in the Manual of Analytical Methods for General Chemical Products; the test results are shown in Table 1.

[0022] Table 1 Test results of indium methanesulfonate solution

[0023] The above is only an embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent substitution, improvement, etc. made within the spirit and principle of the present invention should be included in the scope of the claims of the present invention.

Claims

1. A method for preparing an indium methanesulfonate solution, characterized in that: The following steps are involved: Preparation of high specific surface area metal indium debris: wash the surface of a metal indium bar with an indium content greater than 99.99% with deionized water, dry it, put it into a stainless steel pot, heat it to 160-180°C, melt the solid metal indium bar into liquid metal indium, pour the liquid metal indium into a container filled with 0-20°C deionized water in batches, and the metal indium liquid explodes into high specific surface area metal indium debris when cooled, and fish it out and dry it for later use; Synthesis of indium methanesulfonate: adding the high specific surface area metal indium debris into a reactor, adding a methanesulfonic acid solution with a mass concentration of 35-80%, heating to 105-130° C., maintaining the temperature for reaction to synthesize indium methanesulfonate, cooling, and transferring the indium methanesulfonate reaction solution when the density of the indium methanesulfonate solution in the reactor is 1.55-1.6 g / ml; Preparation of low-free-acid indium methanesulfonate crystals: filtering the indium methanesulfonate reaction solution to obtain a filtrate, concentrating the filtrate, cooling and crystallizing, and centrifuging to obtain low-free-acid indium methanesulfonate crystals; Preparation of indium methanesulfonate solution: slowly adding the low free acid indium methanesulfonate crystals into pre-prepared deionized water while stirring to prepare an indium methanesulfonate solution with an indium ion content of 120-200 g / L and free methanesulfonic acid of 30-50 g / L.

2. The method for preparing an indium methanesulfonate solution according to claim 1, characterized in that: In the process of preparing the high specific surface area metal indium scraps, the melted liquid metal indium is poured into deionized water for cooling according to a volume ratio of 1:2-6.

3. The method for preparing an indium methanesulfonate solution according to claim 1, characterized in that: During the synthesis of the indium methanesulfonate, the mass concentration of methanesulfonic acid is 70%.

4. The method for preparing an indium methanesulfonate solution according to claim 1, characterized in that: In the process of synthesizing the indium methanesulfonate, high specific surface area metal indium chips and methanesulfonic acid are added according to a solid-liquid ratio of 1 g: 1.0-1.6 ml.

5. The method for preparing an indium methanesulfonate solution according to claim 1, characterized in that: The temperature was maintained at 120° C. during the synthesis of the indium methanesulfonate.

6. The method for preparing an indium methanesulfonate solution according to claim 1, characterized in that: In the process of preparing the low free acid indium methanesulfonate crystal, vacuum decompression is used to concentrate until the soluble solid content is 55-65%, and then cooling and crystallizing, wherein the vacuum degree is 30-60 mbar.

7. The method for preparing an indium methanesulfonate solution according to claim 1, characterized in that: In the process of preparing the low-free acid indium methanesulfonate crystals, a centrifuge is used for separation, and the speed of the centrifuge is 2000-4000 rpm.

8. The method for preparing an indium methanesulfonate solution according to claim 7, characterized in that: The separation time of the centrifuge is 10 to 15 minutes.

9. The method for preparing indium methanesulfonate according to claim 1, characterized in that: During the preparation of the indium methanesulfonate solution, the stirring speed is 200-400 r / min.

Images