CN-116623014-B - Method for continuously preparing simple substance arsenic from arsenic-containing material

Abstract

The invention discloses a method for continuously preparing simple substance arsenic from arsenic-containing materials. The method comprises the steps of mixing an arsenic-containing material with carbon powder, carrying out reduction roasting to obtain arsenic-containing steam, contacting and condensing the arsenic-containing steam with spray water to obtain gamma-state elemental arsenic-containing slurry, carrying out reverse flotation on the gamma-state elemental arsenic-containing slurry to remove impurities, and carrying out solid-liquid separation and drying to obtain an elemental arsenic product. The method not only can effectively solve the problems of discontinuous work and low direct yield existing in the existing simple substance arsenic condenser collecting process, but also can greatly reduce the content of impurities in the simple substance arsenic, and is simple, quick, efficient and low in cost, thereby meeting the industrial production.

Inventors

• SUN WEI
• TIAN JIA
• ZHANG XINGFEI
• WANG YUFENG
• HAN HAISHENG
• Hu Wenjihao

Assignees

• 中南大学

Dates

Publication Date

20260512

Application Date

20230526

Claims (7)

1. 1. A method for continuously preparing simple substance arsenic from arsenic-containing materials is characterized by comprising the following steps: 1) Mixing an arsenic-containing material with carbon powder for reduction roasting to obtain arsenic-containing steam; 2) Condensing arsenic-containing steam in contact with spray water to obtain gamma-state elemental arsenic-containing slurry; 3) Removing impurities from the slurry containing gamma-state elemental arsenic through reverse flotation, and performing solid-liquid separation and drying to obtain an elemental arsenic product; In the reverse flotation process, no. 2 oil and/or pine oil is used as a foaming agent, at least one of Z200, methyl isobutyl carbinol and butyl xanthate is used as a collecting agent, and thioglycollic acid and/or sodium sulfide is used as an inhibitor; In the reverse flotation process, the mass concentration of the slurry containing gamma-state elemental arsenic is controlled to be 35-45%, the pH value is 6-8, the potential is 400-450 mV, and the temperature is 20-30 ℃.
2. 2. The method for continuously preparing elemental arsenic from arsenic-containing material according to claim 1, wherein the method comprises the steps of: the arsenic-containing material comprises at least one of crude white arsenic, arsenic sulfide slag and metal arsenate slag.
3. 3. The method for continuously preparing simple substance arsenic from arsenic-containing material according to claim 1 or 2, wherein the mass ratio of the arsenic-containing material to carbon powder is 10:1-3.
4. 4. The method for continuously preparing simple substance arsenic from arsenic-containing material according to claim 1 or 2, wherein the condition of reduction roasting is that roasting is carried out for 2-3 hours at 800-1000 ℃ under a protective atmosphere.
5. 5. The method for continuously preparing elemental arsenic from arsenic-containing material according to claim 1, wherein the shower water is deoxidized water.
6. 6. The method for continuously preparing simple substance arsenic from arsenic-containing materials according to claim 1, wherein in the reverse flotation process, the addition amount of foaming agent is 10-20 g/t, the addition amount of collecting agent is 10-80 mg/L, and the addition amount of inhibitor is 10-200 mg/L.
7. 7. The method for continuously preparing simple substance arsenic from arsenic-containing material according to claim 1, wherein the drying is carried out in vacuum at a drying temperature of 50-60 ℃.

Description

Method for continuously preparing simple substance arsenic from arsenic-containing material Technical Field The invention relates to a method for preparing simple substance arsenic from arsenic-containing materials, in particular to a method for continuously producing crude arsenic (high-quality simple substance arsenic) containing a small amount of impurities by using high-arsenic materials containing various impurities, belonging to the technical field of harmless disposal and resource utilization of arsenic-containing solid wastes. Background A large amount of high-arsenic materials are generated in the nonferrous smelting and environmental treatment processes, for example, white ash is generated in the copper-lead-zinc smelting process, and arsenic sulfide slag, calcium arsenate slag, ferric arsenate slag and the like are generated in the arsenic hazardous waste treatment process. At present, the conventional method for producing high-purity arsenic by using high-arsenic materials is to reduce arsenic-containing components in the high-arsenic materials into crude arsenic products in a reduction roasting mode, and then purify the crude arsenic into high-purity arsenic by a vacuum distillation and chlorination reduction method. However, there are two bottleneck problems in the process application, namely, firstly, the problem of continuous and efficient collection of coarse arsenic and secondly, the problem of impurity separation in the process of preparing high-purity arsenic. Aiming at the recycling problem of crude arsenic, the existing collection method mainly utilizes the property that arsenic steam generates alpha-state elemental arsenic at 280-460 ℃ and recycles metallic elemental arsenic in a condensation area in a crystallizer. For example, in the device for producing elemental arsenic designed in chinese patent (bulletin CN 213060988U), the temperature of the condenser needs to be reduced to below 50 ℃ when the elemental arsenic is collected, then the top cover of the condenser is opened, and finally the bulk metallic elemental arsenic condensed on the inner wall of the condenser tube is dropped and recovered by vibration or knocking. Clearly, recovery of elemental arsenic by the crystallizer not only presents a production discontinuity problem, but also risks arsenic vapor leakage. Meanwhile, in order to improve the crystallization efficiency of the simple substance arsenic, the surface area of the condensing tube needs to be increased, the metal simple substance arsenic crystallization on the inner wall of the condensing tube is not easy to fall off, the surface area of the inner wall of the condensing tube is finally reduced continuously, a layer of thick simple substance arsenic crystallization is accumulated, the crystallization efficiency of the simple substance arsenic is finally reduced gradually, and the direct yield of the simple substance arsenic is also reduced continuously. Clearly, improving the manner in which elemental arsenic is collected is necessary to increase the efficiency of the elemental arsenic production process and the recovery of elemental arsenic. The complexity of the high purity arsenic production process depends on the composition and content of impurities in the raw arsenic feed. For example, when the high arsenic material contains sulfate, the crude arsenic produced by the reduction roasting will contain elemental sulfur impurities. In the process of preparing high-purity arsenic by subsequent crude arsenic vacuum distillation, the boiling point of elemental sulfur volatilized in the form of S 2 is close to that of the elemental arsenic, so that the elemental sulfur is difficult to separate from As, and the sulfur content in the final high-purity arsenic product is higher. Similarly, impurities such as Sb, cu, pb and the like in the high-arsenic material in the reduction roasting process also enter the crude arsenic product to different degrees, so that the difficulty in subsequent high-purity arsenic preparation is increased. Obviously, if the impurity content can be reduced from the raw material end of the crude arsenic, the quality of the high-purity arsenic is greatly improved, and the preparation difficulty of the high-purity arsenic is also greatly reduced. Disclosure of Invention Aiming at the collection problem and impurity separation problem of simple substance arsenic in the prior art, the invention aims to provide a method for continuously preparing simple substance arsenic from arsenic-containing materials, which utilizes the characteristic that high-temperature arsenic steam is crystallized into gamma-state simple substance arsenic below 100 ℃, can continuously cool the high-temperature arsenic steam by adopting a spray water condensation mode and efficiently collect gamma-state simple substance arsenic slurry, and then removes impurity components in the simple substance arsenic by utilizing the difference of hydrophobicity of impurities such as sim