CN110550611A - Method for efficiently leaching tellurium from copper separating slag of copper anode slime enhanced by external field effect - Google Patents

Abstract

The invention relates to nonferrous metal hydrometallurgy technology, in particular to a method for efficiently leaching tellurium from copper anode slime and copper slag by external field action. The present invention comprises the following steps: grinding raw material of copper-separating slag; using sodium hydroxide as leaching liquid and sodium chlorate as oxidizing agent, mixing with raw materials to prepare a mixed material liquid; placing the mixed material liquid on an ultrasonic-microwave synergistic reaction workstation, setting Ultrasonic power and microwave power parameters, under the external field strengthening effect of ultrasonic or microwave or ultrasonic-microwave synergy, the leaching reaction is carried out according to a certain liquid-solid ratio and continuous stirring; the solution obtained in the previous step is taken out and leached under normal pressure. Suction filtration is performed on the obtained solution to obtain a tellurium-containing leaching solution. The invention utilizes external field ultrasonic and microwave assisted strong oxidation leaching, which has the characteristics of short processing time, fast leaching speed, low energy consumption, etc., can destroy the structure of copper separation slag, realize efficient leaching of tellurium under normal pressure, and increase the leaching rate of tellurium by 26 —35%.

Description

A method for enhancing the efficient leaching of tellurium from copper anode slime copper slag by external field action

technical field

The invention relates to nonferrous metal hydrometallurgy technology, in particular to a method for efficiently leaching tellurium from copper anode slime and copper slag by external field action, and efficiently leaching the valuable metal Te in the copper slag, thereby increasing the leaching rate of tellurium.

Background technique

Tellurium is a rare element, and its abundance is the smallest among metals and nonmetals (the average abundance is 6×10 ^-6 %). Tellurium in copper anode slime mainly exists in the form of Cu ₂ Te, Ag ₂ Te, Au ₂ Te, PbTe, TeO ₂ and other compounds. Tellurium and its compounds are widely used: (1) to produce cadmium telluride thin-film solar cells; (2) as an alloy additive to improve the machinability of steel; (3) as a trace additive to improve the machinability of copper alloys without reducing the electrical conductivity (4) As a vulcanizing agent, rubber processing accelerator and catalyst component for synthetic fiber production.

Most of the recyclable tellurium in the world is associated with copper, gold and other minerals. The main source of industrial tellurium production is the anode slime produced in the electrolytic refining process of copper and lead. During the copper electrolytic refining process, the copper on the anode and the base metal with a negative potential dissolve into the solution, while the metal with a positive potential does not dissolve and falls to the bottom of the tank to become copper anode slime. The basic steps of extracting Te from the principle of hydrometallurgy technology: copper slag crushing, ball milling, leaching, purification, neutralization, calcination, alkali dissolution and electrowinning to obtain high-purity tellurium. Separation and recovery of tellurium.

Copper separation slag contains a large amount of rare elements, the existing extraction process is relatively complicated, the leaching rate of tellurium is low, it is difficult to increase the leaching rate by 70%, and the reaction time is long.

Contents of the invention

The purpose of the present invention is to provide a method for the effective leaching of tellurium from copper anode slime and copper slag by external field action strengthening. ), efficiently leaching the valuable metal Te from the copper slag, and improving the tellurium leaching rate. It can not only be leached under low temperature and normal pressure, reduce energy consumption, but also shorten the leaching time. The leaching time of copper slag is reduced from the current 90-120min to 14min-44min. The processing capacity is large, the tellurium leaching rate is high, and other valuable The concentration of metals is conducive to comprehensive recycling.

The present invention comprises the following steps:

Step 1, grinding the copper slag raw material;

Step 2, taking sodium hydroxide as the leaching solution and sodium chlorate as the oxidizing agent, mixing the raw materials of step 1 to prepare the mixed material liquid;

Step 3, place the mixed material liquid of step 2 on the ultrasonic-microwave synergistic reaction workstation (existing equipment), set the ultrasonic power and microwave power parameters, under the external field strengthening effect of ultrasonic or microwave or ultrasonic-microwave synergy, press certain The liquid-solid ratio and continuous stirring for leaching reaction;

Step 4, taking out the solution obtained in step 3, leaching for 1-30 minutes under normal pressure, and discharging the material, performing suction filtration on the obtained solution, and obtaining a tellurium-containing leachate by suction filtration;

The concentration of sodium hydroxide in the step 2 is 0.4-1.4mol/L, and the addition of sodium chlorate is 0.8-1.5 times of the actual addition of copper slag raw material;

In step 3, the ultrasonic power is 0-500W, the microwave power is 0-700W, and the liquid-solid ratio is 4-10:1.

The copper-separating slag raw material in step 1 is ground to more than 200 mesh.

In step 3, the stirring speed is 100-300r/min.

The mass percentages of the main components of the copper slag in step 1 are: Pb: 15-16.06%, Ag: 14-14.9%, Ba: 14-16.43%, Sn: 8-9.02%, Te: 3-3.64%, Cu: 2-2.88%.

The principle of the present invention: put the mixed material liquid in the ultrasonic-microwave synergistic reaction work, (1) under the action of ultrasonic wave, accelerate the mass transfer and heat transfer, so that the surface film of the copper separation slag is destroyed to a certain extent, so that the particle surface Exposed to promote solid-liquid reaction. At the same time, the phenomenon of "turbulent flow" appears in the solution, which produces a large number of "microbubbles" to form a cavitation effect, which reduces the diffusion resistance and the activation energy of the reaction; The polarization properties of the molecules inside the slag are closely related. The polarized molecules with positive and negative poles are arranged in an orderly manner in the magnetic field. When the direction of the magnetic field changes, the polarized molecules continue to rotate at high speed, thereby generating heat. The solution can be heated rapidly, the leaching reaction is promoted, the leaching rate of tellurium in the metallurgical process is increased, the reaction time is shortened, and compared with the traditional hydrometallurgy, the amount of waste gas and waste liquid is reduced, which is beneficial to environmental protection. Due to the characteristics of microwave and ultrasonic waves, this method has higher utilization value than traditional hydrometallurgy.

Main chemical reaction equation of the present invention is as follows:

3TeO ₂ +6OH ^- +ClO ₃ ^- ＝3TeO ₄ ^2- +3H ₂ O+Cl ^- ;

3Pb ₅ TeO ₇ +36OH ^- +ClO ₃ ^- = 3TeO ₄ ^2- +15PbO ₂ ^2- +Cl ^- +18H ₂ O.

The present invention uses external ultrasonic and microwave assisted strong oxidation leaching, which has the characteristics of short processing time, fast leaching speed, low energy consumption, etc., can destroy the structure of copper separation slag, and realize high-efficiency leaching of tellurium under normal pressure, as can be seen in Table 2 Tellurium leaching rate increased by 26-35%.

Detailed ways

The present invention will be further described in detail below in conjunction with specific embodiments.

The used copper slag chemical composition of the example of the present invention is as follows table 1:

Table 1 Copper slag raw material chemical composition table

element Cu Ag Ba Pb Te sn content 2.88% 14.9% 16.43% 16.06% 3.64% 8.83%

.

Example 1:

Step 1, grinding 10g of copper slag raw materials to more than 200 mesh;

Step 2, mixing the sodium hydroxide solution and 8g sodium chlorate with a concentration of 1mol/L to prepare the mixed material liquid;

Step 3, place the mixed material liquid of step 2 in the ultrasonic-microwave synergistic reaction workstation, set the basic parameters of the ultrasonic-microwave synergistic reaction workstation, the ultrasonic power is 150W, the control liquid-solid ratio is 9:1, turn on the stirrer, at 150r /min stirring speed and reaction conditions of 30min for leaching reaction.

In step 4, the solution obtained in step 3 is taken out and placed under normal pressure for leaching for 20 minutes, and then the material is discharged, and the tellurium-containing leach solution is obtained by suction filtration, and the tellurium leaching rate is 87.98%.

Example 2:

Step 1, grinding 10g of copper slag raw materials to more than 200 mesh;

Step 2, mixing the sodium hydroxide solution and 12g sodium chlorate with a concentration of 1.2mol/L to prepare the mixed material liquid;

Step 3, place the mixed material liquid obtained in step 2 in the ultrasonic-microwave synergistic reaction workstation, set the basic parameters of the ultrasonic-microwave synergistic reaction workstation, the microwave power is 700W, the control liquid-solid ratio is 10:1, open the stirrer, and The leaching reaction was carried out under the conditions of a stirring speed of 300r/min and a reaction time of 240s.

In step 4, the solution obtained in step 3 is taken out and placed under normal pressure for leaching for 20 minutes, and then the material is discharged, and the tellurium-containing leach solution is obtained by suction filtration, and the tellurium leaching rate is 91.08%.

Example 3:

Step 1, grinding 10g of copper slag raw materials to more than 200 mesh;

Step 2, mixing the sodium hydroxide solution and 15g sodium chlorate with a concentration of 1mol/L to prepare the mixed material liquid;

Step 3, put the mixed material liquid in step 2 in the ultrasonic-microwave synergistic reaction workstation, set the basic parameters of the ultrasonic-microwave synergistic reaction workstation, the ultrasonic power is 300W, the microwave power is 300W, the control liquid-solid ratio is 8:1, open Stirrer, the leaching reaction was carried out under the conditions of a stirring speed of 300r/min and a reaction time of 10min.

In step 4, the solution obtained in step 3 is taken out and placed under normal pressure for leaching for 20 minutes, and then the material is discharged, and the tellurium-containing leach solution is obtained by suction filtration, and the tellurium leaching rate is 90.67%.

Example 4:

Step 1, grinding 10g of copper slag raw materials to more than 200 mesh;

Step 2, mixing the sodium hydroxide solution and 10g sodium chlorate with a concentration of 0.8mol/L to prepare a mixed material liquid;

Step 3, place the mixed material liquid in step 2 in the ultrasonic-microwave synergistic reaction workstation, set the basic parameters of the ultrasonic-microwave synergistic reaction workstation, the ultrasonic power is 150W, the microwave power is 450W, the control liquid-solid ratio is 9:1, open Stirrer, the leaching reaction was carried out under the conditions of a stirring speed of 300r/min and a reaction time of 5min.

In step 4, the solution obtained in step 3 is taken out and placed under normal pressure for leaching for 20 minutes, and then the material is discharged, and the tellurium-containing leach solution is obtained by suction filtration, and the tellurium leaching rate is 93.29%.

Example 5:

Step 1, grinding 10g of copper slag raw materials to more than 200 mesh;

Step 2, mixing the sodium hydroxide solution and 15g sodium chlorate with a concentration of 1.2mol/L to prepare the mixed material liquid;

Step 3, place the mixed material liquid obtained in step 2 in the ultrasonic-microwave synergistic reaction workstation, set the basic parameters of the ultrasonic-microwave synergistic reaction workstation, the ultrasonic power is 450W, the microwave power is 150W, and the control liquid-solid ratio is 9:1, Turn on the agitator, and carry out the leaching reaction under the conditions of a stirring speed of 300r/min and a reaction time of 15min.

In step 4, the solution obtained in step 3 is taken out and placed under normal pressure for leaching for 20 minutes, and then the material is discharged, and the tellurium-containing leach solution is obtained by suction filtration, and the tellurium leaching rate is 88.3%.

Embodiment 6:

Step 1, grinding 10g of copper slag raw materials to more than 200 mesh;

Step 2, mixing sodium hydroxide solution and 12g sodium chlorate with a concentration of 0.6mol/L to prepare a mixed material liquid;

Step 3, place the mixed material liquid obtained in step 2 in the ultrasonic-microwave synergistic reaction workstation, set the basic parameters of the ultrasonic-microwave synergistic reaction workstation, the ultrasonic power is 300W, the microwave power is 300W, and the control liquid-solid ratio is 7:1, The stirrer was turned on, and the leaching reaction was carried out under the conditions of a stirring speed of 300r/min and a reaction time of 18.41min.

In step 4, the solution obtained in step 3 is taken out and placed under normal pressure for leaching for 20 minutes, and then the material is discharged, and the tellurium-containing leach solution is obtained by suction filtration, and the tellurium leaching rate is 86.2%.

Embodiment 7:

Step 1, grinding 10g of copper slag raw materials to more than 200 mesh;

Step 2, mixing the sodium hydroxide solution and 15g sodium chlorate with a concentration of 1.4mol/L to prepare the mixed material liquid;

Step 3, place the mixed material liquid obtained in step 2 in the ultrasonic-microwave synergistic reaction workstation, set the basic parameters of the ultrasonic-microwave synergistic reaction workstation, the ultrasonic power is 150W, the microwave power is 150W, and the control liquid-solid ratio is 9:1, Turn on the agitator, and carry out the leaching reaction under the conditions of a stirring speed of 300r/min and a reaction time of 5min.

In step 4, the solution obtained in step 3 is taken out and placed under normal pressure for leaching for 20 minutes, and then the material is discharged, and the tellurium-containing leach solution is obtained by suction filtration, and the tellurium leaching rate is 95.3%.

Embodiment 8 (comparative test):

Take the copper anode slime and separate the copper slag into a 250mL beaker, pour 1.2mol/L sodium hydroxide solution at a liquid-solid ratio of 9:1 (optimum), put it in a water bath dry pot, start stirring, and slowly add the oxidant chlorine Sodium acid, seal the mouth of the beaker with a plastic film and start timing, leaching under normal pressure for 2 hours, remove the film and filter after the leaching reaction is completed, the leaching rate of tellurium is only 59.98% through chemical analysis.

Table 2 The process parameters and leaching rate contrast of the embodiment of the present invention and comparative example

Example Ultrasonic power/w Microwave power/w Leaching time/min Tellurium leaching rate/% 1 150 0 50 88 2 0 700 twenty four 91.1 3 300 300 30 90.7 4 150 450 25 93.3 5 450 150 35 88.3 6 300 300 38 86.2 7 150 150 25 95.3 traditional method 0 0 120 59.9

It can be seen from Table 2 that compared with traditional hydrometallurgy, the method of the present invention, under alkaline conditions, through ultrasonic-microwave synergistic strong oxidation of tellurium in copper slag, the reaction time is greatly shortened, and the leaching rate of tellurium is significantly improved.

Claims (6)

1. A method for efficiently leaching tellurium in the copper anode slime copper slag that is strengthened by external field action, is characterized in that, comprises the following steps: Step 1, grinding the copper slag raw material; Step 2, taking sodium hydroxide as the leaching solution and sodium chlorate as the oxidizing agent, mixing the raw materials of step 1 to prepare the mixed material liquid; Step 3, place the mixed material liquid in step 2 on the ultrasonic-microwave synergistic reaction workstation, set the ultrasonic power and microwave power parameters, under the external field strengthening effect of ultrasonic or microwave or ultrasonic-microwave synergy, according to a certain liquid-solid ratio and Continuous stirring for leaching reaction; Step 4, taking out the solution obtained in step 3, leaching for 1-30 minutes under normal pressure, and discharging the material, performing suction filtration on the obtained solution, and obtaining a tellurium-containing leachate by suction filtration; The concentration of sodium hydroxide in described step 2 is 0.4-1.4mol/L, and the addition of sodium chlorate is 0.8-1.5 times of the actual addition of copper slag raw material; In the step 3, the ultrasonic power is 0-500W, the microwave power is 0-700W, and the liquid-solid ratio is 4-10:1. 2. the method for efficiently leaching tellurium in a kind of external field action strengthening copper anode slime copper slag according to claim 1, it is characterized in that, main chemical reaction is as follows: 3TeO ₂ +6OH ^- +ClO ₃ ^- ＝3TeO ₄ ^2- +3H ₂ O+Cl ^- ; 3Pb ₅ TeO ₇ +36OH ^- +ClO ₃ ^- = 3TeO ₄ ^2- +15PbO ₂ ^2- +Cl ^- +18H ₂ O. 3. A method for efficiently leaching tellurium from copper anode slime and copper slag enhanced by external field action according to claim 1, characterized in that: the raw material of copper separation slag in step 1 is ground to more than 200 mesh. 4. A method for efficiently leaching tellurium from copper anode slime and copper slag enhanced by external field action according to claim 1, characterized in that the stirring speed in step 3 is 100-300r/min. 5. A method for efficiently leaching tellurium from copper anode sludge by external field action according to claim 1, characterized in that the mass percentage of the main component of the copper slag in step 1 is: Pb: 15-16.06%, Ag: 14-14.9%, Ba: 14-16.43%, Sn: 8-9.02%, Te: 3-3.64%, Cu: 2-2.88%. 6. the method for efficiently leaching tellurium in a kind of external field action strengthening copper anode slime copper slag according to claim 1, is characterized in that, is specifically implemented as: Step 1, grinding 10g of copper slag raw materials to more than 200 mesh; Step 2, mixing the sodium hydroxide solution and 15g sodium chlorate with a concentration of 1.4mol/L to prepare the mixed material liquid; Step 3, place the mixed material liquid of step 2 on the ultrasonic-microwave synergistic reaction workstation, set the basic parameters of the ultrasonic-microwave synergistic reaction workstation, the ultrasonic power is 150W, the microwave power is 150W, and the control liquid-solid ratio is 9:1, Turn on the agitator, and carry out the leaching reaction under the condition of stirring speed of 300r/min and reaction for 5min; In step 4, the solution obtained in step 3 was taken out, leached under normal pressure for 20 minutes, and then the material was discharged, and the tellurium-containing leachate was obtained by suction filtration, and the tellurium leaching rate was 95.3%.