CN1140209A

CN1140209A - Bismuth sulfide ore hydrometallurgy method

Info

Publication number: CN1140209A
Application number: CN96103248A
Authority: CN
Inventors: 江培海; 邱定蕃; 张寅生; 王成彦; 王含渊
Original assignee: Beijing General Research Institute of Mining and Metallurgy
Current assignee: Beijing General Research Institute of Mining and Metallurgy
Priority date: 1996-03-13
Filing date: 1996-03-13
Publication date: 1997-01-15
Anticipated expiration: 2016-03-13
Also published as: CN1042752C

Abstract

The invention relates to a bismuth sulfide ore hydrometallurgy method, which is characterized in that bismuth sulfide ore is put into an anode area with a diaphragm for leaching, sulfur is oxidized into element sulfur, bismuth enters into electrolyte in an ionic state, bismuth ions in the electrolyte are separated out on a cathode through the diaphragm to obtain metal bismuth powder, and metal bismuth is obtained through refining, so that the leaching and electrodeposition processes of the bismuth sulfide ore are completed in the same leaching electrolytic tank. The leaching electrolysis process is carried out at natural temperature, so that the energy consumption is saved, the method has the advantages of short process flow, high metal recovery rate, low cost, no pollution and the like, and the method can also be used for treating sulfide ores of other element types.

Description

Bismuth sulfide ore hydrometallurgy method

The invention relates to a hydrometallurgical method for treating bismuth sulfide ore, in particular to a hydrometallurgical method forbismuth sulfide concentrate ore and bismuth sulfide middling ore, which can be used for extracting metal bismuth from bismuth sulfide ore.

At present, many hydrometallurgical methods for producing metal bismuth by treating bismuth sulfide ore at home and abroad mainly comprise an iron trichloride leaching method, a hydrochloric acid-nitrous acid leaching method, a hydrochloric acid-sulfuric acid leaching method and the like, and the basic principle is that FeCl is used₃、Cl₂Using the bismuth sulfide as an oxidant and a complexing agent to oxidize and leach the bismuth sulfide oreThe bismuth solution is subjected to hydrolysis, iron powder replacement or electrodeposition to produce bismuth oxychloride or sponge bismuth. And reducing, smelting and refining the bismuth oxychloride and the sponge bismuth to obtain the No. 1 metal bismuth. These metallurgical processes have the following drawbacks: 1. the oxidant has strong corrosivity and strict requirements on equipment materials. 2. The ion concentration of the solution is high, and particularly, the solution viscosity is high when the concentration of ferric trichloride is high, so that the liquid-solid separation is difficult. 3. When the hydrolysis method is adopted, the dilution times are high, a large amount of water is consumed, and the treatment capacity of the wastewater is increased. 4. The replacement method consumes a certain amount of iron, and FeCl is oxidized by using chlorine₂Is FeCl₃And returning to leaching. 5. The consumption of auxiliary raw materials is high, such as hydrochloric acid, ferric trichloride, chlorine and the like.

The invention aims to establish a novel leaching electrolysis process, so as to fully utilize the oxidizing capability of an anode in the electrolysis process to replace the oxidant in the process and reduce the production cost.

The invention is characterized in that:

a. the method comprises the following steps of preparing bismuth sulfide concentrate, pulping middlings, placing the middlings into an anode region of a leaching electrolytic tank, stirring, and introducing direct current to a cathode and an anode of the electrolytic tank, oxidizing sulfur in the bismuth sulfide ore into elemental sulfur, enabling bismuth metal ions to enter electrolyte, discharging and separating bismuth ions in the electrolyte on the cathode in a cathode chamber to obtain metallic sponge bismuth or bismuth particles, wherein the leaching electrolytic tank is divided into the anode region and a cathode region, two cathodes are arranged in the tank and are isolated from the anode region by a diaphragm, and two anode plates are respectively arranged on two sides outside the diaphragm to form the anode region;

b. the leaching electrolysis control conditions are as follows: the current density is 20-300A/m²The temperature of the electrolyte is 20-90 ℃, the voltage of the cell is 0.9-4.0V, the polar distance is 50-110mm, and the ratio of pulp to liquid and solid (l/s)3-5: 1, stirring speed 300-;

c. leaching out Bi as an electrolyte component³⁺5-30g/l、Cl^-100-250g/l、HCl0.3-1M；

d. The cathode and the anode are made of graphite, and the diaphragm of the leaching electrolytic cell is made of acid-resistant fabric (such as allen, chlorolon, terylene and the like) so as to effectively prevent the penetration of ore pulp and not influence the transmission of metal ions.

The basic principle of the leaching electrolysis method for treating the bismuth sulfide ore is to fully utilize the anode reaction in the electrolysis process. Bismuth sulfide ore, bismuth, the main form of bismuth is bismuth stilbite (Bi)₂S₃) Oxide (Bi)₂O₃) And a small amount of metallic bismuth. The ore slurry mainly reacts in four forms in the anode chamber.

1. The mineral particles impinge on the anode and are directly oxidized.

(1)

2. The electrolyte contains a small amount of iron ions (iron in the concentrate is dissolved out during leaching) and is oxidized into Fe at the anode³⁺The ferric iron ions are then reduced to Fe²⁺，Fe²⁺Is oxidized again into Fe on the anode³⁺And repeating the steps to ensure that the bismuthate is completely leached, wherein the reaction formula is as follows:

(2)

(3)

3. because of the chloride system, the side reaction of chlorine evolution is carried out on the anode, the produced chlorine has oxidability, and the reaction with the bismuthate is as follows:

(4)

4. in the acid chloride system, bismuthine has a small amount of solubility:

(5)

fe in solution³⁺Or Cl₂H is to be₂S is oxidized to elemental sulfur.

(6)

(7)

Bismuth mine constantly dissolving, H₂S is continuously oxidized until leaching is completed.

FIG. 1 is a process flow diagram of the present invention

FIG. 2 is a schematic diagram of a leaching electrolytic cell

FIG. 3 is a schematic plan view of a leaching cell

In figure 2 and figure 3, the leaching electrolytic bath consists of a stirring paddle (1), an anode (2), a diaphragm (3), a cathode (4) and a bath body (5). Namely, cathodes (4) are respectively hung at two ends in the tank body, a diaphragm (3) is used for isolating two hung anodes from the cathodes in the middle part of the tank body to form an anode leaching area, and stirring pulp (1) is added between the two anodes for stirring and leaching the bismuth sulfide ore pulp. The structure of the large leaching electrolytic cell can be formed into a plurality of groups according to the principle structure shown in figure 2, namely, an anode chamber formed by stirring pulp and a hanging anode is separated from a cathode chamber by a diaphragm like an open cloth bag.

The metallurgical process includes pulping bismuth sulfide ore or bismuth sulfide middling ore into anode chamber, stirring and leaching, maintaining the leached liquid in certain acidity, temperature and liquid-solid ratio, controlling certain current density and bath voltage, electrolyzing electrically, making bismuth in bismuth sulfide ore enter the solution in ion state, and separating out sponge bismuth.

The method for treating the bismuth sulfide ore by adopting the leaching electrolysis method has the advantages that: 1. the process flow is short, the leaching and the electrodeposition are carried out simultaneously, bismuth in the anode chamber is leached into electrolyte, bismuth in the cathode chamber electrolyte is reduced into sponge bismuth or bismuth particles, and then the sponge bismuth or bismuth particles are smelted into metal bismuth ingots. 2. The ion concentration in the solution is low, and the difficulty of filtration and washing does not exist. 3. The operation is carried out at a lower temperature (60 ℃), the corrosion phenomenon is greatly improved, and the corrosion-resistant material is easy to solve. 4. The auxiliary raw materials are less. 5. The energy consumption and the acid consumption are low. 6. The solution is basically circulated in a closed loop, only a small amount of solution needs to be treated, and the three wastes are easy to treat. 7. The recovery rate of valuable metals is high.

Example 1

The metallurgical method of the invention is adopted to carry out small-scale test on the bismuth sulfide ore, and the raw material components are (%): bi22.7; fe23.4; pb0.82; cu0.47; s32.99;Mo1.73；Sb0.016；As0.049；SiO₂8.60；CaO3.08；MgO0.17；Ag110g/t。

the leaching electrolysis is carried out in an electrolytic cell with the volume of 5L, the electrolytic cell is divided into an anode chamber and a cathode chamber by a diaphragm, 20-600g of ore sample is weighed and placed in the anode chamber, the cathode chamber is mechanically stirred to suspend ore pulp, the stirring speed is 350-700r/min, the temperature of the electrolyte is controlled at 40-95 ℃, the time is 90-210min, the acidity is 5-45g/L, and Cl is^-50-200g/l, liquid-solid ratio of 3-20: 1, current density of 20-200A/m²And the average cell voltage is 0.8-1.5V.

The comprehensive test reaches good indexes, the bismuth content of the leaching slag is less than or equal to 0.2 percent, the silver content is less than 20g/t, the leaching rate respectively reaches 99.49 percent and 93 percent, the direct current power consumption for treating each ton of concentrate is 180kwh, the acid consumption is 300kg/t ore, the bismuth content of sponge produced in a cathode region is 80-98 percent, the iron content is less than 0.2 percent, and the silver content is 190 plus material weight is 250 g/t.

Example 2

An expansion test of leaching electrolysis was carried out, the volume of the electrolytic cell being 1m³The ore sample is processed by 30-60kg each time, and the percentage of the concentrate is as follows: bi32.92; fe19.60; s32.40; SiO 2₂15.52; CaO2.15; MgO0.10. Percentage of middling: bi7.79; fe26.80; s31.45; SiO 2₂6.75; CaO6.60; MgO0.33. Leaching electrolysis conditions: current density of 100-²The current intensity is 400-800A, the average cell pressure is 2.9-4.0, the electrolysis time is 4-19h, the electrolysis temperature is 60 ℃, and the electrolyte component g/l: bi 10-20; cl^-150-200；H⁺0.5-1 m. Leaching residue components: bi0.3-0.8%. The bismuth leaching rate is as follows: 99% of concentrate and 95% of middling. The produced sponge comprises the following components in percentage by weight: bi is more than 80, Fe is less than 0.2. The direct current power consumption is 2300kwh/tBi, and the bismuth subcsponge is subjected to reduction smelting and refining processes to produce bismuth subclause 1.

Claims

1. The invention relates to a hydrometallurgical method for treating bismuth sulfide ore, which is characterized by comprising the following steps:

a. placing slurried bismuth sulfide concentrate and middling into an anode chamber ofa leaching electrolytic cell, wherein the anode chamber is isolated from a cathode chamber by a diaphragm, stirring is carried out in the anode chamber, and direct current is supplied for carrying out an electrolysis process;

b. the leaching electrolysis control conditions are as follows: the current density is 20-300A/m²The temperature of the electrolyte is 20-90 ℃, the voltage of the tank is 0.9-4.0V, the polar distance is 50-110mm, the liquid-solid ratio of ore pulp is 3-5.1, and the stirring speed is 300-;

c. leaching electrolyte components: bi³⁺5-30g/l、Cl-100-250g/1、HCl0.3-1M；

2. The leaching electrolysis cell of claim 1, wherein the cathode and the anode are made of graphite, and the diaphragm of the leaching electrolysis cell is made of acid-resistant fabric (such as allen, chlorolon, dacron and the like).