阅读说明：本技术 一种膜电极法制备硒化氢的方法 (Method for preparing hydrogen selenide by membrane electrode method ) 是由 宁红锋 冯晓青 莫杰 蒲云平 纪淼 赵强 胡通 于 2020-12-31 设计创作，主要内容包括：本发明涉及一种膜电极法制备高纯硒化氢的方法,包括如下步骤：将超纯水分别加入电解槽阳极室和阴极室,所述阳极室和所述阴极室通过阳离子半透膜隔开,以单质硒为阴极,进行电解；电解过程中,收集电解槽阴极室产生的气体,经纯化后,制备得到硒化氢。该制备方法采用高纯单质硒作为阴极,有效提高了硒的转化效率,转化效率可以高达95％；而且由阴极室制备得到的气体经去除氢气和水蒸气后,即可获得高纯硒化氢,不仅避免了复杂的纯化工艺,还减少了污染排放物。(The invention relates to a method for preparing high-purity hydrogen selenide by a membrane electrode method, which comprises the following steps: respectively adding ultrapure water into an anode chamber and a cathode chamber of an electrolytic cell, wherein the anode chamber and the cathode chamber are separated by a cation semipermeable membrane, and elemental selenium is taken as a cathode for electrolysis; and in the electrolysis process, collecting gas generated in the cathode chamber of the electrolysis bath, and purifying to prepare the hydrogen selenide. The preparation method adopts high-purity elemental selenium as the cathode, effectively improves the conversion efficiency of the selenium, and the conversion efficiency can reach 95 percent; and the gas prepared from the cathode chamber can be used for obtaining high-purity hydrogen selenide after removing hydrogen and water vapor, so that not only is a complex purification process avoided, but also pollution emissions are reduced.)

1. A preparation method of hydrogen selenide is characterized by comprising the following steps: respectively adding ultrapure water into an anode chamber and a cathode chamber of an electrolytic cell, wherein the anode chamber and the cathode chamber are separated by a cation semipermeable membrane, and elemental selenium is taken as a cathode for electrolysis; and in the electrolysis process, collecting gas generated in the cathode chamber of the electrolysis bath, and purifying to prepare the hydrogen selenide.

2. The method of claim 1, wherein one side of the anode of the electrolytic cell is in intimate contact with the cation exchange membrane and one side of the cathode is in intimate contact with the cation exchange membrane.

3. The production method according to claim 1 or 2, wherein the anode of the electrolytic cell is a sheet-like membrane electrode.

4. A method according to claim 1 or 2, wherein the anode of the cell is an inert metal, preferably platinum or gold.

5. The production method according to claim 4, wherein the surface of the anode is provided with a catalyst layer; preferably, the catalyst is selected from the group consisting of metallic platinum, ruthenium oxide or yttrium oxide, more preferably yttrium oxide;

preferably, the thickness of the catalyst layer is 50 to 200 μm.

6. The method of claim 1 or 2, wherein the elemental selenium has a purity of greater than 99% and a sulfur content of less than 100 ppm;

preferably, the cathode is a plate-shaped body having a thickness of 10-30 cm.

7. The production method according to claim 1 or 2, wherein the current of the electrolysis is 0.1 to 0.5A.

8. An electrolytic cell device for preparing hydrogen selenide, which is characterized by comprising an electrolytic cell body, an anode, a cathode and a cation semipermeable membrane;

the anode and the cathode are arranged on two sides of the cation semipermeable membrane and are oppositely arranged, and the anode and the cathode are respectively in close contact with the cation semipermeable membrane;

the cathode is made of elemental selenium;

the electrolytic cell body is divided into two chambers by the cation semipermeable membrane, wherein the two chambers are an anode chamber and a cathode chamber respectively, the anode chamber is used for accommodating anolyte, and the cathode chamber is used for accommodating catholyte;

the anolyte and the catholyte are ultrapure water.

9. The electrolyzer unit of claim 8 characterized in that the anode and cathode are fixedly connected to the cationic semi-permeable membrane, respectively, preferably by means of heat welding.

10. The electrolyzer unit of claim 8 wherein the anode is a sheet membrane electrode;

preferably, the anode is an inert metal, such as metallic platinum or metallic gold;

preferably, the surface of the anode is provided with a catalyst layer, and the catalyst is selected from metal platinum, ruthenium oxide or yttrium oxide, preferably yttrium oxide;

preferably, the thickness of the catalyst layer is 50 to 200 μm;

preferably, the purity of the elemental selenium is more than 99%, and the sulfur content of the elemental selenium is less than 100 ppm;

preferably, the cathode is a plate-shaped body having a thickness of 10-30 cm.

Technical Field

The invention relates to the technical field of electronic gas production, in particular to a method for preparing high-purity hydrogen selenide by a membrane electrode method.

Background

Hydrogen selenide electronic gas is widely used in the semiconductor industry, solar energy industry, laser industry and aerospace industry. Since the electronic gas of hydrogen selenide is a highly toxic, flammable and explosive gas, hydrogen selenide is heated or has great risks in the processes of production, storage, transportation and use.

The existing hydrogen selenide production processes mainly comprise two processes, one is metal selenide and hydrogen selenide prepared by hydrolysis synthesis reaction, the process belongs to wet reaction, the reaction speed is severe, the metal selenide is easy to react violently when meeting water, the reaction speed needs to be controlled, the product quality is not easy to control, the environmental pollution is easy to cause, the conversion efficiency of the hydrolysis synthesis method selenium is low, the conversion efficiency of the selenium is not more than 50%, the pollution is serious, the purification process is complex, and the selenium raw material is seriously wasted. The second process is a direct high-temperature chemical method of high-purity elemental selenium and high-purity hydrogen, the utilization rate of the hydrogen and the selenium is about 50%, the separation technology of the hydrogen selenide gas and the elemental selenium is complex, the separated hydrogen and the elemental selenium need to be reused, and the environment pollution is avoided. Moreover, both of the above methods require the construction of a special chemical plant for producing and purifying hydrogen selenide, and the purified hydrogen selenide is stored in steel cylinders and transported to the site of use.

Disclosure of Invention

The invention aims to provide a method for preparing high-purity hydrogen selenide by a membrane electrode method.

To this end, in a first aspect, the present invention provides a method for preparing hydrogen selenide, comprising the steps of: respectively adding ultrapure water into an anode chamber and a cathode chamber of an electrolytic cell, wherein the anode chamber and the cathode chamber are separated by a cation semipermeable membrane, and elemental selenium is taken as a cathode for electrolysis; and in the electrolysis process, collecting gas generated in the cathode chamber of the electrolysis bath, and purifying to prepare the hydrogen selenide.

In the preparation method provided by the invention, the gas generated in the cathode chamber contains hydrogen selenide and hydrogen and water vapor, so that the high-purity hydrogen selenide can be prepared by collecting the gas generated in the cathode chamber of the electrolytic cell and removing the hydrogen and the water vapor.

Further, the ultrapure water has a resistivity of 18.2 M.OMEGA.. cm (25 ℃ C.) or more.

Further, the anode of the electrolytic cell is a sheet membrane electrode.

Further, the anode is an inert metal, such as metallic platinum or metallic gold.

Further, the surface of the anode is provided with a catalyst layer, and the catalyst is selected from metal platinum, ruthenium oxide or yttrium oxide, preferably yttrium oxide.

Further, the thickness of the catalyst layer is 50 to 200 μm.

Furthermore, the purity of the elemental selenium is more than 99%, and the sulfur content of the elemental selenium is less than 100 ppm.

Further, the cathode is a plate-shaped body with the thickness of 10-30 cm.

Further, one side of the anode is in close contact with the cation exchange membrane, and one side of the cathode is in close contact with the cation exchange membrane.

According to the preparation method provided by the invention, the electrolysis equation of the anode is as follows:

6H₂O→3O_2(g)+12e^-+12H⁺

the electrolysis equation for the cathode is as follows:

Se+2H⁺+2e^-→H₂Se_(g)

meanwhile, the cathode electrolysis has accompanying side reactions, and the equations of the side reactions are as follows:

2H⁺+2e^-→H_2(g)

in specific embodiments, the cationic semipermeable membrane is selected from the group consisting of dupont Nafion membrane, Dow membrane from Dow, Dow Xus-B204 membrane, 3M perfluorocarbon membrane, japan asaplex from asahi, asahi nitroxide Flemion, chlorine engineering C series, Ballard BAM membrane, belgium Solvay membrane, eastern mountain group DF988 proton exchange membrane, eastern mountain group DF2801 proton exchange membrane; nafion membranes from DuPont and Dow membranes from Dow are preferred.

Further, the current of the electrolysis is 0.1-0.5A.

A second aspect of the present invention provides an electrolytic cell apparatus for producing hydrogen selenide, the electrolytic cell apparatus comprising an electrolytic cell body, an anode, a cathode and a cationic semipermeable membrane;

the anode and the cathode are arranged on two sides of the cation semipermeable membrane and are oppositely arranged, and the anode and the cathode are respectively in close contact with the cation semipermeable membrane;

the cathode is made of elemental selenium;

the electrolytic cell body is divided into two chambers by the cation semipermeable membrane, wherein the two chambers are an anode chamber and a cathode chamber respectively, the anode chamber is used for accommodating anolyte, and the cathode chamber is used for accommodating catholyte;

the anolyte and the catholyte are ultrapure water.

Furthermore, the anode and the cathode are respectively and fixedly connected with the cation semipermeable membrane.

Furthermore, the anode and the cathode are respectively and fixedly connected with the cation semipermeable membrane in a hot melting mode.

Further, the anode is a sheet membrane electrode.

Further, the anode is an inert metal, such as metallic platinum or metallic gold.

Further, the surface of the anode is provided with a catalyst layer, and the catalyst is selected from metal platinum, ruthenium oxide or yttrium oxide, preferably yttrium oxide.

Further, the thickness of the catalyst layer is 50 to 200 μm.

Furthermore, the purity of the elemental selenium is more than 99%, and the sulfur content of the elemental selenium is less than 100 ppm.

Further, the cathode is a plate-shaped body with the thickness of 10-30 cm.

Compared with the prior art, the invention has the following remarkable advantages:

(1) the invention adopts high-purity elemental selenium as the cathode, effectively improves the conversion efficiency of selenium, and the conversion efficiency can reach 95 percent; and the gas prepared from the cathode chamber can be used for obtaining high-purity hydrogen selenide after removing hydrogen and water vapor, so that not only is a complex purification process avoided, but also pollution emissions are reduced.

(2) In a preferred embodiment of the present invention, the anode, the cation semipermeable membrane and the cathode are in close contact with each other without a gap therebetween, and hydrogen ions are generated at the contact surface between the anode and the cation semipermeable membrane by electrolyzing water in the cation semipermeable membrane by the anode, and the generated hydrogen ions reach the cathode through the cation semipermeable membrane directly and react with the cathode. In the prior art, because pure water has a relatively high resistance, an electrolyte is often required to be additionally added to enable an electrolytic reaction to be smoothly carried out, which often brings about some side reactions; by adopting the design, hydrogen ions can directly reach the cathode through the cation semipermeable membrane after being generated, so that the anolyte can efficiently carry out electrolytic reaction without adding extra electrolyte. In the electrolytic process, the electrolytic voltage and the electrolytic current are obviously changed, and the flow stability and the high purity of the hydrogen selenide gas can be ensured while the electrolytic process is simplified.

(3) The preparation method provided by the invention can be used for preparing the hydrogen selenide electronic gas in the using field, the online production and use of the hydrogen selenide electronic gas can be realized, the amount of the electronic gas can be produced by field electrolysis according to the amount of the hydrogen selenide electronic gas, the storage problem of the hydrogen selenide electric gas is basically avoided in the using field, the use and the storage of a large number of electronic gas steel cylinders are avoided, and the raw material for preparing the hydrogen selenide electronic gas is solid or liquid and has no risk of diffusion in the atmosphere.

Drawings

Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the invention. Also, like reference numerals are used to refer to like parts throughout the drawings. In the drawings:

fig. 1 is a schematic diagram of hydrogen selenide prepared by electrolysis according to the preparation method provided by the invention.

1-cathode chamber gas discharge pipe, 2-cathode chamber shell, 3-cathode, 4-catholyte, 5-cathode chamber cavity, 6-cathode cable, 7-cation semipermeable membrane, 8-first double O ring, 9-cation semipermeable membrane fixing frame, 10-second double O ring, 11-anode cable, 12-anode, 13-anolyte, 14-anode chamber cavity, 15-anode chamber shell and 16-anode chamber gas discharge pipe.

Detailed Description

Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

The preparation method of hydrogen selenide provided by the invention can be implemented by the electrolytic cell device shown in figure 1. Referring to fig. 1, the electrolyzer apparatus comprises an electrolyzer body, an anode 12, a cathode 3 and a cationic semi-permeable membrane 9; the anode 12 and the cathode 3 are arranged on two sides of the cation semipermeable membrane 9, the anode 12 and the cathode 3 are oppositely arranged, and the anode 12 and the cathode 3 are respectively in close contact with the cation semipermeable membrane 9; further preferably fixedly, for example by means of heat welding. The cathode is made of elemental selenium; the electrolytic cell body by cation semi-permeable membrane 9 separates for two cavities in anode chamber and cathode chamber, the anode chamber is used for holding 13 ultrapure water of anolyte, the cathode chamber is used for holding 4 ultrapure water of catholyte.

In a specific mode, a first double O ring 8 is adopted for sealing between the cathode chamber shell 2 and the cation semipermeable membrane fixed frame 9, and a second double O ring 10 is adopted for sealing between the anode chamber shell 15 and the cation semipermeable membrane fixed frame 9, so that no hydrogen selenide gas and electrolyte are leaked between sealing surfaces. The part of the fixed cationic semipermeable membrane frame 9 inside the electrolytic cell is an integrated membrane electrode, the cationic semipermeable membrane 7 only allows hydrogen ions to penetrate through the cationic semipermeable membrane 7 from the anolyte 13 into the catholyte 3, and other ions do not allow through the cationic semipermeable membrane 7. The anode 12 is thermally welded to the surface of the cation semipermeable membrane 7 adjacent to the anolyte 13. The anode 12 is led out of the anode chamber housing 15 through the anode cable 11 and connected to a power supply, and after the anode 12 is energized, electrolysis occurs at the interface of the anode 12 and the anolyte 13 to produce oxygen. The electrolysis equation for the anode is as follows:

6H₂O→3O_2(g)+12e^-+12H⁺

the anode 12 is made of an inert metal, such as platinum or titanium, and the inert metal is coated with a catalyst, which may be platinum, ruthenium oxide or yttrium oxide. The anode 12 is a sheet-like membrane electrode. Upon energization, electrolysis occurs at the interface of anode 12 and the anolyte producing oxygen which collects in the headspace of anode chamber 14 and exits the cell through anode chamber gas outlet line 16.

The cathode 3 is connected to a power supply through a cathode cable 6, and the cathode 3 is in close contact with the cationic semipermeable membrane 7 and is in direct current communication. The cathode 3 adopts blocky elemental selenium, in a specific embodiment, the cathode 3 is a plate-shaped electrode with sulfur content less than 100ppm and purity more than 99% of selenium, and the plate-shaped electrode is 10-30 cm.

The cathode 3 is contacted with the catholyte, the cathode 3 is a consumable electrode, the cathode 3 of the elemental selenium block is smaller and smaller along with the electrolytic process, the cathode 3 and the catholyte both participate in the electrolytic reaction, and the electrolytic equation is as follows:

Se+2H⁺+2e^-→H₂Se_(g)

meanwhile, electrolysis is accompanied by side reactions, the equations of which are as follows:

2H⁺+2e^-→H_2(g)

after the power is switched on, hydrogen and hydrogen selenide gas are generated on the contact surface of the elemental selenium cathode 3 and the cathode electrolyte, the generated gas is gathered in the top space of the cathode chamber cavity 5, and then the gas is discharged out of the electrolytic cell through the cathode chamber gas discharge pipe 1.

Example 1

The anode adopts ruthenium oxide with the thickness of 50 mu M plated with titanium and the size of 4cm multiplied by 4cm, the cathode adopts 99 percent elemental selenium with the thickness of 10cm and the thickness of 4cm multiplied by 4cm and the sulfur content of 100ppm, the proton exchange membrane is a DuPont 117Nafion membrane, the electrolyte is ultrapure water (18.2M omega cm), the current is kept at 0.1A, the electrolysis is stopped when the voltage is sharply increased, 765.6g of dry hydrogen selenide gas is collected, and the selenium conversion rate is 97 percent.

EXAMPLE 2

The anode adopts 200 mu M metal platinum with the size of 3cm multiplied by 3cm, the cathode adopts 99 percent elemental selenium with the thickness of 10cm and the sulfur content of 3cm multiplied by 3cm, the proton exchange membrane is a Shandong Yue group DF988 membrane, the electrolyte is ultrapure water (18.2M omega cm), the current is kept at 0.1A, the electrolysis is stopped when the voltage is sharply increased, 354.5g of dry hydrogen selenide gas is collected, and the selenium conversion rate is 79 percent.

The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the appended claims.