CN103320616A - Method for recovering copper through copper anode mud supersonic pretreatment - Google Patents

Abstract

The invention belongs to the field of wet metallurgy, and specifically relates to a method for recovering copper through a copper anode mud supersonic pretreatment. According to the invention, sulfuric acid with concentration of 50-400g/L is added to copper anode mud, such that slurry is prepared; the copper anode mud slurry is placed in a supersonic wave generator; an oxidant is added into the copper anode mud slurry; supersonic frequency is regulated to 20-40kHz, a power is 500-4000w, and leaching is carried out for 30-90min under normal pressure and a temperature of 20-90 DEG C. With the method, a problem of long leaching time and generally low leaching rate of prior art are overcome. Compared with the leaching rate with no supersonic treatment, the leaching rate is improved by more than 10-30%, and a copper leaching rate reaches 93-99%.

Description

A method for recovering copper by ultrasonic pretreatment of copper anode slime

technical field

The invention belongs to the field of hydrometallurgy, and in particular relates to a method for recovering copper through ultrasonic pretreatment of copper anode slime.

Background technique

When copper is electrolytically refined, the copper on the anode and the base metal with negative potential dissolve into the solution under the action of direct current, while the rare precious metal sinks to the bottom of the tank due to its high dissolution potential to become anode slime. The pretreatment of anode slime is to dissociate the non-precious metal elements in the anode slime that will significantly affect the subsequent separation process and be easily separated. This will not only enrich the rare and precious metal elements, but also facilitate the recovery of other valuable elements. Copper occupies a large proportion in copper anode slime, and its presence has a significant impact on the subsequent separation of precious metals, so it needs to be pretreated and recovered.

For copper anode slime pretreatment decopper, fire oxidation acid leaching or normal pressure air decopper method are currently used at home and abroad. The recovery of sulfur dioxide produced in the roasting process in the pyrotechnic process and the resulting environmental pollution are still a technical problem; while the atmospheric acid leaching copper removal process can not produce sulfur dioxide, but because the reaction temperature of the air oxidation method cannot be very high, the highest It does not exceed 90°C, so the reaction intensity is weak and the reaction time is long. It takes 24 hours or even longer to complete the copper removal task, and the copper removal rate is only about 60~70%.

In order to solve the problems of slow speed, low efficiency and long time consumption in the process of copper removal by acid leaching under atmospheric pressure, the high temperature and pressure acid leaching process for copper removal has gradually attracted attention. The high temperature and pressure method has the advantages of short processing time, large processing capacity, and fast leaching speed, but it also has disadvantages such as high energy consumption and high equipment requirements. While the leaching rate of the target element is increased, the leaching rate of various associated elements is also increased. At the same time, it is not conducive to the recovery of other elements.

Contents of the invention

Aiming at the deficiencies of existing methods, the present invention provides a copper anode slime ultrasonic pretreatment method for recovering copper. Low energy consumption, no need for special high-pressure equipment, and fast leaching speed. By adopting the method of the invention, the processing time is short, the processing capacity is large, continuous feeding and discharging operations are possible, and the copper recovery rate is high; the direction of other valuable metals in the copper anode slime is reasonable and concentrated, which is beneficial to comprehensive recovery.

The method for realizing the object of the present invention is carried out according to the following steps:

(1) Add water to the copper anode slime for coarse slurry adjustment, sieve out sand impurities with a particle diameter greater than 5mm, drain the water, and add sulfuric acid with a concentration of 50 ~ 400g/L to the drained copper anode slime Slurry adjustment, control the weight concentration of copper anode mud slurry at 1~30%;

(2) Put the obtained copper anode slurry in an ultrasonic generator, add an oxidizing agent to the copper anode slurry, adjust the ultrasonic frequency to 20~40kHz, and the power to 500~4000w, under normal pressure at a temperature of 20~90°C Under the leaching for 30~90min, the copper in the copper anode slime is leached in the form of CuSO ₄ .

The oxidizing agent is one or both of compressed air, industrial pure oxygen, oxygen-enriched air or _{H2O2 . When using H2O2} , the amount of _H2O2 is 0.05~ _1molH2O2 per liter of _slurry material.

Compared with prior art, feature and beneficial effect of the present invention are:

The principle of the present invention is to make the copper anode mud slurry exhibit turbulent mechanical properties under the action of ultrasonic waves and reduce the diffusion resistance. At the same time, ultrasonic waves play a key role in destroying the boundary layer, accelerating mass transfer, heat transfer, and promoting the dispersion of fine particles. The surface film of the anode slime particles is destroyed to a certain extent, and the surface of the particles is exposed.

Ultrasonic cavitation breaks the crystallized and grown grains, refines the grains, strengthens the mass transfer, reduces the resistance during leaching, and accelerates the reaction. The present invention uses sulfuric acid and hydrogen peroxide as the medium, Acid leaching to remove copper from copper anode slime has the characteristics of normal pressure operation, fast reaction speed and high leaching rate.

The main chemical reaction equation that the inventive method relates to is as follows:

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Compared with prior art, the advantage of the inventive method is:

①Using ultrasonic waves to strengthen the leaching process of copper anode slime not only increases the mass transfer rate of the reaction at the molecular level, but also reduces the activation energy of the reaction. Mass transfer, heat transfer, promote the dispersion of fine particles, and increase the leaching speed;

② Fast reaction rate and high leaching rate. It overcomes the problems of longer leaching time and lower leaching rate in most cases in the existing process, and the leaching rate is increased by more than 10-30% compared with the leaching rate without ultrasonic treatment under the same conditions, and the copper leaching rate reaches 93~99%;

③The leaching process is at normal pressure, without a large amount of heat supply, energy saving and emission reduction, and cost reduction. In the existing technology, the leaching reaction temperature is higher than 90° C., and the leaching process pressure is as high as 1.2 MPa.

Detailed ways

The present invention is further described below in conjunction with embodiment.

The copper anode slime used in the example of the present invention is provided by Jinchuan Company, and the composition of used copper anode slime is as follows:

element Au Ag Cu Ni Se Te content 172.9 g t ^-1 2.60% 12.11% 47.36% 3.22% 0.369%

After leaching, the copper ions in the leach solution were analyzed by inductively coupled plasma emission spectrometer and the leaching rate was calculated.

Example 1

(1) Add water to the copper anode slime for coarse slurry adjustment, sieve out sand impurities with a particle diameter greater than 5mm, drain the water, and add sulfuric acid with a concentration of 400g/L to the drained copper anode slime for slurry adjustment , control the weight concentration of copper anode mud slurry at 5%;

(2) Place the obtained copper anode slurry in an ultrasonic generator, pass compressed air into the copper anode slurry, adjust the ultrasonic frequency to 40kHz, and the power to 500w, and leaching at 20°C under normal pressure for 90min, copper The copper in the anode slime is leached in the form of CuSO ₄ .

After leaching, the leaching rate of copper was analyzed to be 95.5%.

Example 2

(1) Add water to the copper anode slime for coarse slurry adjustment, sieve out sand impurities with a particle diameter greater than 5mm, drain the water, and add sulfuric acid with a concentration of 50g/L to the drained copper anode slime for slurry adjustment , control the weight concentration of copper anode mud slurry at 20%;

(2) Place the obtained copper anode slurry in an ultrasonic generator, add H ₂ O ₂ to the copper anode slurry, the amount of H ₂ O ₂ is 1mol H ₂ O ₂ /per liter of slurry, and adjust the ultrasonic frequency to 20kHz, power 1000w, leaching at 65°C for 60min under normal pressure, the copper in the copper anode slime is leached in the form of CuSO ₄ .

After leaching, the leaching rate of copper was analyzed to be 98.1%.

Example 3

(1) Add water to the copper anode slime for coarse slurry adjustment, sieve out sand impurities with a particle diameter greater than 5mm, drain the water, and add sulfuric acid with a concentration of 200g/L to the drained copper anode slime for slurry adjustment , control the weight concentration of copper anode mud slurry at 1%;

(2) Put the obtained copper anode slurry in an ultrasonic generator, add H ₂ O ₂ to the copper anode slurry, the amount of H ₂ O ₂ is 0.05molH ₂ O ₂ /per liter of slurry, adjust the ultrasonic frequency 30kHz, power 2000w, leaching at 90°C for 30min under normal pressure, the copper in the copper anode slime is leaching in the form of CuSO ₄ .

After leaching, the leaching rate of copper was analyzed to be 97.4%.

Example 4

(1) Add water to the copper anode slime for coarse slurry adjustment, sieve out sand impurities with a particle diameter greater than 5mm, drain the water, and add sulfuric acid with a concentration of 300g/L to the drained copper anode slime for slurry adjustment , control the weight concentration of copper anode mud slurry at 30%;

(2) Place the obtained copper anode slurry in an ultrasonic generator, add oxygen-enriched air and industrial pure oxygen to the copper anode slurry, adjust the ultrasonic frequency to 30kHz, and the power to 4000w, at 45°C under normal pressure After leaching for 80min, the copper in the copper anode slime is leached in the form of CuSO ₄ .

After leaching, the leaching rate of copper was analyzed to be 96.8%.

Example 5

(1) Add water to the copper anode slime for coarse slurry adjustment, sieve out sand impurities with a particle diameter greater than 5mm, drain the water, and add sulfuric acid with a concentration of 150g/L to the drained copper anode slime for slurry adjustment , control the weight concentration of copper anode mud slurry at 15%;

(2) Place the obtained copper anode slurry in an ultrasonic generator, add industrial pure oxygen and H ₂ O ₂ to the copper anode slurry, and the amount of H ₂ O ₂ is 0.5mol H ₂ O ₂ per liter of slurry , adjust the ultrasonic frequency to 25kHz, the power to 1500w, and leaching at 20°C for 40min under normal pressure, the copper in the copper anode slime is leached in the form of CuSO ₄ .

After leaching, the leaching rate of copper was analyzed to be 95.1%.

comparative example

Add water to the copper anode slime for coarse slurry adjustment, sieve to remove sand impurities with a particle diameter greater than 5mm, drain the water, add sulfuric acid with a concentration of 300g/L to the drained copper anode slime for slurry adjustment, and control copper The weight concentration of the anode slurry is 30%. Add oxygen-enriched air to the copper anode slurry, and leaching at 20°C for 10 hours under normal pressure. After the leaching, the leaching rate of copper is only 65.5%.

Table 1 The process parameters and leaching rate comparison of the embodiment of the present invention and the comparative example

Example temperature/℃ Acidity/gL ^-1 Leaching time/min Copper leaching rate/% 1 20 400 90 95.5 2 65 50 60 98.1 3 90 200 30 97.4 4 45 300 80 96.8 5 20 150 40 95.1 traditional method 20 300 600 65.5

As can be seen from the above table, compared with the traditional method, the method of the present invention has a stronger reaction intensity, greatly shortens the reaction time, and significantly improves the leaching rate of copper.

Claims (2)

1. a copper anode mud ultrasonic pretreatment reclaims the method for copper, it is characterized in that carrying out according to following steps:

(1) adds water in the copper anode mud and carry out the coarse adjustment slurry, sieve degranulation diameter is greater than the grains of sand class impurity of 5mm, drain away the water, the sulfuric acid that adds concentration in the copper anode mud after drain away the water and be 50 ~ 400g/L is sized mixing, and the weight concentration of control copper anode mud slurry is 1 ~ 30%;

(2) the copper anode mud slurry with gained places ultrasonic generator, add oxygenant in the copper anode mud slurry, the adjusting ultrasonic frequency is 20 ~ 40kHz, and power is 500 ~ 4000w, in 20 ~ 90 ℃ of lower 30 ~ 90min that leach of temperature, the copper in the copper anode mud is with CuSO under normal pressure ₄Form leaches.

2. a kind of copper anode mud ultrasonic pretreatment according to claim 1 reclaims the method for copper, it is characterized in that described oxygenant is pressurized air, industrial pure oxygen, oxygen-rich air or H ₂O ₂In one or both, adopt H ₂O ₂The time H ₂O ₂Consumption be 0.05 ~ 1molH ₂O ₂Every liter of slurry.