CN113184905B

CN113184905B - Impurity removing method for arsenic trichloride high-boiling residue

Info

Publication number: CN113184905B
Application number: CN202110521020.3A
Authority: CN
Inventors: 贾行伟; 殷亮; 沃尔特·德巴兹; 朱刘; 曾小东; 郭金伯
Original assignee: First Rare Materials Co Ltd
Current assignee: First Rare Materials Co Ltd
Priority date: 2021-05-12
Filing date: 2021-05-12
Publication date: 2023-04-18
Anticipated expiration: 2041-05-12
Also published as: CN113184905A

Abstract

The present disclosure provides an impurity removal method for arsenic trichloride high-boiling residue, wherein the impurities of the arsenic trichloride high-boiling residue comprise Se, sb, fe and Bi, and the method comprises the following steps: mixing an arsenic trichloride high-boiling residue and a sulfuric acid solution according to a certain proportion, stirring, and separating to obtain a crude arsenic trichloride solution and a sulfuric acid solution containing impurities; and step two, distilling the crude arsenic trichloride solution obtained in the step one at 130-140 ℃ to further remove impurities to obtain a fine arsenic trichloride solution. According to the method, the arsenic trichloride high-boiling residues are washed and purified by using a sulfuric acid solution, the arsenic trichloride obtained after sulfur removal is carried out in a distillation mode is high in purity, and the fine arsenic trichloride enters a high-purity arsenic production system for recycling, so that the generation of arsenic-containing wastewater and waste residues is reduced, the method is easy to operate, the use amount of reagents is small, and the method is environment-friendly.

Description

Impurity removing method for arsenic trichloride high-boiling residue

Technical Field

The disclosure relates to the technical field of metallurgy, in particular to an impurity removal method for arsenic trichloride high-boiling residues.

Background

The high-purity arsenic is mainly applied to the fields of manufacturing compound semiconductors such as gallium arsenide, indium arsenide and the like, infrared transmission glass, high-purity hard alloy, medicine, health and the like. The chlorination-reduction method is a common preparation method of high-purity arsenic, and mainly takes 95% -99% crude arsenic as a raw material, the high-purity arsenic is prepared through the process steps of vacuum sublimation, chlorine chlorination, rectification purification, hydrogen reduction and the like, a part of arsenic trichloride high-boiling residues are generated in the rectification purification process, the impurity content is high, the arsenic trichloride high-boiling residues cannot enter the next production process, and the arsenic trichloride high-boiling residues need to be discharged from a production system for treatment.

The existing main treatment mode of the arsenic trichloride high-boiling residue is to hydrolyze the arsenic trichloride high-boiling residue, a large amount of arsenic-containing wastewater and arsenic-containing waste residue are generated in the mode, the treatment cost is high, the arsenic-containing waste residue has the risk of causing secondary pollution, and the method is not environment-friendly.

Therefore, the treatment of the arsenic trichloride high-boiling residue is a technical problem to be solved by research in the technical field.

Disclosure of Invention

In view of the problems in the background art, the present disclosure aims to provide a method for removing impurities from high-boiling arsenic trichloride.

In order to achieve the above object, the present disclosure provides an impurity removal method for arsenic trichloride high-boiling residue, wherein the impurities of arsenic trichloride high-boiling residue include Se, sb, fe, and Bi, and the method includes the following steps: mixing an arsenic trichloride high-boiling residue and a sulfuric acid solution according to a certain proportion, stirring, and separating to obtain a crude arsenic trichloride solution and a sulfuric acid solution containing impurities; and step two, distilling the crude arsenic trichloride solution obtained in the step one at 130-140 ℃ to further remove impurities to obtain a fine arsenic trichloride solution.

In some embodiments, the mass fraction of the sulfuric acid solution in step one is 40% to 98%.

In some embodiments, the mass ratio of the arsenic trichloride high-boiling residue to the sulfuric acid solution in the first step is 1: 1-10: 1.

In some embodiments, the stirring speed in step one is 200 to 800r/min.

In some embodiments, the separation method in step one is liquid separation.

In some embodiments, the impurities in step two include sulfur, antimony.

The beneficial effects of this disclosure are as follows:

according to the method, the arsenic trichloride high-boiling residues are washed and purified by using a sulfuric acid solution, the arsenic trichloride obtained after sulfur removal is carried out in a distillation mode is high in purity, and the fine arsenic trichloride enters a high-purity arsenic production system for recycling, so that the generation of arsenic-containing wastewater and waste residues is reduced, the method is easy to operate, the use amount of reagents is small, and the method is environment-friendly.

Detailed Description

The method for removing impurities from the high boiling point arsenic trichloride according to the present disclosure is explained in detail below.

The application discloses an impurity removal method for arsenic trichloride high-boiling residues, which comprises the following steps: mixing an arsenic trichloride high-boiling residue and a sulfuric acid solution according to a certain proportion, stirring, and separating to obtain a crude arsenic trichloride solution and a sulfuric acid solution containing impurities; and step two, distilling the crude arsenic trichloride solution obtained in the step one at 130-140 ℃ to further remove impurities to obtain a fine arsenic trichloride solution.

In some embodiments, the arsenic trichloride high boiler impurity comprises Se, sb, fe, bi.

In some embodiments, the mass fraction of the sulfuric acid solution in step one is 40% to 98%. The arsenic trichloride high-boiling residue is not soluble in high-concentration sulfuric acid solution, but the arsenic trichloride reacts with water to generate arsenic hydroxide and hydrogen chloride, so that the arsenic trichloride is easy to hydrolyze when low-concentration sulfuric acid solution is used, and in order to avoid the problem, the sulfuric acid solution has a higher concentration, and the mass fraction of the concentration of the sulfuric acid solution is 40% -98%.

In some embodiments, a sulfuric acid solution is selected for impurity removal in step one. The sulfuric acid solution and the arsenic trichloride are not mutually soluble, the solubility of impurities such as Se, sb, fe, bi and the like in the arsenic trichloride and the sulfuric acid solution is different, the arsenic trichloride is washed by the sulfuric acid solution to remove impurities, and the impurities such as Se, sb, fe, bi and the like in the arsenic trichloride enter the sulfuric acid solution to achieve the impurity removal effect.

In some embodiments, the mass ratio of the arsenic trichloride high-boiling substance to the sulfuric acid solution in the first step is 1: 1-10: 1. When the sulfuric acid solution is too little to remove impurities, the impurity residue is too much; when the sulfuric acid solution is excessive, more arsenide enters the sulfuric acid solution, so that the yield of the fine trichloro arsenic is reduced.

In some embodiments, the stirring speed in step one is 200 to 800r/min. When the stirring speed is less than 200r/min, the mixing is not uniform, and the impurity removal effect is influenced; when the stirring speed is more than 800r/min, the sulfuric acid solution is splashed, and the risk of the experiment is increased.

In some embodiments, the separation method in step one is liquid separation. Because the sulfuric acid solution and the arsenic trichloride high-boiling residue are incompatible. It is thus separated in the form of a liquid fraction.

In some embodiments, in step two, the crude arsenic trichloride solution in step one is distilled at 130 ℃ to 140 ℃ to further remove impurities. As the boiling point of the arsenic trichloride is about 130 ℃, the arsenic trichloride is distilled at 130-140 ℃ to obtain the fine arsenic trichloride.

In some embodiments, the impurities in step two include sulfur, antimony.

[ test procedures and test results ].

Example 1

Step one, mixing 1000g of arsenic trichloride high-boiling-point substance (Fe: 6mg/L, bi:133mg/L, sb:1008mg/L, se:136 mg/L) and 200g of 50% sulfuric acid solution, and stirring at the rotation speed of 300r/min to obtain 962g of crude arsenic trichloride liquid (Fe: 1mg/L, bi:3mg/L, sb;371mg/L, se:43mg/L, S:14 mg/L) and sulfuric acid solution containing impurities;

and step two, distilling the crude arsenic trichloride solution obtained in the step one at 130-140 ℃ to further remove impurities to obtain 941g of fine arsenic trichloride solution (Fe is less than 1mg/L, bi is less than 1mg/L, sb is 2mg/L, se is 8mg/L, and S is less than 1 mg/L).

Example 2

Step one, mixing 1000g of arsenic trichloride high-boiling residue (Fe: 8mg/L, bi:156mg/L, sb:986mg/L, se:113 mg/L) and 200g of 60% sulfuric acid solution, and stirring at the rotating speed of 600r/min to obtain 978g of crude arsenic trichloride liquid (Fe: 1mg/L, bi:2mg/L, sb: 324mg/L, se:37mg/L, S:29 mg/L) and sulfuric acid solution containing impurities;

and step two, distilling the crude arsenic trichloride solution in the step one at 130-140 ℃ to further remove impurities to obtain 957g of fine arsenic trichloride solution (Fe & lt 1mg/L, bi & lt 1mg/L, sb & lt 1mg/L, se & lt 6mg/L, S & lt 1 mg/L).

The embodiment shows that the arsenic trichloride is high in purity after the heavy fraction of arsenic trichloride is washed and subjected to impurity removal by using a sulfuric acid solution and then subjected to sulfur removal by a distillation mode, and the fine arsenic trichloride enters a high-purity arsenic production system for reutilization, so that the generation of arsenic-containing wastewater and waste residues is reduced, the operation is easy, the reagent consumption is low, and the environment-friendly effect is realized.

The above-disclosed features are not intended to limit the scope of practice of the present disclosure, and therefore, all equivalent variations that are described in the claims of the present disclosure are intended to be included within the scope of the claims of the present disclosure.

Claims

1. An impurity removing method for arsenic trichloride high-boiling residue comprises Se, sb, fe and Bi, and is characterized by comprising the following steps:

mixing an arsenic trichloride high-boiling residue and a sulfuric acid solution according to a certain proportion, stirring, and separating to obtain a crude arsenic trichloride solution and a sulfuric acid solution containing impurities;

step two, distilling the crude arsenic trichloride solution obtained in the step one at 130-140 ℃ to further remove impurities to obtain a fine arsenic trichloride solution;

the mass ratio of the arsenic trichloride high-boiling residue to the sulfuric acid solution in the first step is 1: 1-10:1;

the separation method in the first step is liquid separation.

2. The method for removing impurities from arsenic trichloride high-boiling residue according to claim 1, wherein the mass fraction of the sulfuric acid solution in the first step is 40-98%.

3. The method for removing impurities from arsenic trichloride high-boiling residue according to claim 1, wherein the stirring speed in the first step is 200 to 800r/min.

4. The method for removing impurities from arsenic trichloride high-boiling residue according to claim 1, wherein the impurities in the second step comprise sulfur and antimony.