Method for comprehensively recovering valuable metal from copper tellurium slag

Abstract

The invention discloses a method for comprehensively recovering valuable metal from copper tellurium slag. The copper tellurium slag is dissolved by using nitric acid, so that silver, copper and bismuth in the copper tellurium slag are basically dissolved in a solution; tellurium is oxidized into tellurium oxide, thereby entering undissolved slag. Silver, copper and bismuth are separated and recovered via fractional precipitation of the solution; and tellurium is separated and recovered via alkaline leaching of the undissolved slag. The method solves the problems that cost of a conventional process is high, copper recovery rate and tellurium recovery rate are not high, and that silver and bismuth cannot be recovered in the conventional process; influences on the environment of the production process are reduced; a whole process is simple; and pollutions toward the environment is small. The method is simple in the whole production process, low in cost and small pollutions toward the environment, has high comprehensive recovery rate, and realizes complete separation of silver, copper, bismuth and tellurium. The obtained products have high purity; and the recovery rate of silver, copper, bismuth and tellurium is higher than 99%.

Description

Technical field:

[0001] The invention relates to a copper-tellurium slag recovery method, in particular to a method for comprehensively recovering valuable metals from copper-tellurium slag. Background technique:

[0002] At present, in the copper leaching process of the wet treatment anode mud, 25-50% of the tellurium in the anode mud enters the copper separation solution. This part of the tellurium is mainly replaced by copper powder to produce copper tellurium slag for recovery. The main component of copper tellurium slag is copper telluride, in addition to copper, bismuth, silver and other metals. There are two main methods for the comprehensive recovery of traditional copper tellurium slag:

[0003] Method 1: Copper-tellurium residue is leached copper with sulfuric acid and oxidant, and then alkaline leaching is used to separate tellurium. Its disadvantages are: low leaching rate of copper and tellurium; a large amount of expensive oxidants are required; silver and bismuth i...

Examples

Embodiment 1

[0019] Take 2 tons of copper-tellurium slag, in terms of mass fraction, its composition is: copper: 35.6%, tellurium 13.92%, bismuth 6.34%, silver 3.16%.

[0020] (1) Add 2000L of pure water to the stirred reactor, and while stirring, put the above 2 tons of copper tellurium slag into the reactor, and turn on the acid gas absorption tower. According to the copper tellurium slag: 75% by mass, the mass ratio of concentrated nitric acid is 1: The proportion of 2 is 75% concentrated nitric acid by mass. Add 75% concentrated nitric acid by mass to the reaction kettle at a flow rate of about 5L / min. The reaction temperature is controlled at 85-90°C during the acid addition process, and the temperature is kept at 85-90°C after the acid is added. -90°C for 2 hours. The acid gas produced in the reaction process is absorbed by the water in the acid gas absorption tower into dilute acid water, which can be returned to dissolve copper tellurium slag after being concentrated. After the coppe...

Embodiment 2

[0026] Taking 1.8 tons of copper-tellurium slag, in terms of mass fraction, its components are: copper: 30.3%, tellurium 15.62%, bismuth 5.52%, and silver 2.28%.

[0027] (1) Add 2700L of pure water to the reactor, add 1.8 tons of copper tellurium slag to the reactor while stirring, and turn on the acid gas absorption tower. According to the copper tellurium slag: 75% by mass, the mass ratio of concentrated nitric acid is 1: Measure 75% concentrated nitric acid with a mass percentage of 2.5. Add nitric acid to the reactor at a flow rate of about 5L / min. During the acid addition, the reaction temperature is controlled to 85-90°C. After the acid addition is completed, keep it at 85-90°C for 3 hours , The acid gas produced during the reaction process is absorbed into dilute acid water by the water in the acid gas absorption tower, which can be returned to dissolve copper tellurium slag after being concentrated. After the copper and tellurium slag is dissolved, air is blown into the ...

Technical field:

[0001] The invention relates to a copper-tellurium slag recovery method, in particular to a method for comprehensively recovering valuable metals from copper-tellurium slag. Background technique:

[0002] At present, in the copper leaching process of the wet treatment anode mud, 25-50% of the tellurium in the anode mud enters the copper separation solution. This part of the tellurium is mainly replaced by copper powder to produce copper tellurium slag for recovery. The main component of copper tellurium slag is copper telluride, in addition to copper, bismuth, silver and other metals. There are two main methods for the comprehensive recovery of traditional copper tellurium slag:

[0003] Method 1: Copper-tellurium residue is leached copper with sulfuric acid and oxidant, and then alkaline leaching is used to separate tellurium. Its disadvantages are: low leaching rate of copper and tellurium; a large amount of expensive oxidants are required; silver and bismuth i...

Examples

Embodiment 1

[0019] Take 2 tons of copper-tellurium slag, in terms of mass fraction, its composition is: copper: 35.6%, tellurium 13.92%, bismuth 6.34%, silver 3.16%.

[0020] (1) Add 2000L of pure water to the stirred reactor, and while stirring, put the above 2 tons of copper tellurium slag into the reactor, and turn on the acid gas absorption tower. According to the copper tellurium slag: 75% by mass, the mass ratio of concentrated nitric acid is 1: The proportion of 2 is 75% concentrated nitric acid by mass. Add 75% concentrated nitric acid by mass to the reaction kettle at a flow rate of about 5L / min. The reaction temperature is controlled at 85-90°C during the acid addition process, and the temperature is kept at 85-90°C after the acid is added. -90°C for 2 hours. The acid gas produced in the reaction process is absorbed by the water in the acid gas absorption tower into dilute acid water, which can be returned to dissolve copper tellurium slag after being concentrated. After the coppe...

Embodiment 2

[0026] Taking 1.8 tons of copper-tellurium slag, in terms of mass fraction, its components are: copper: 30.3%, tellurium 15.62%, bismuth 5.52%, and silver 2.28%.

[0027] (1) Add 2700L of pure water to the reactor, add 1.8 tons of copper tellurium slag to the reactor while stirring, and turn on the acid gas absorption tower. According to the copper tellurium slag: 75% by mass, the mass ratio of concentrated nitric acid is 1: Measure 75% concentrated nitric acid with a mass percentage of 2.5. Add nitric acid to the reactor at a flow rate of about 5L / min. During the acid addition, the reaction temperature is controlled to 85-90°C. After the acid addition is completed, keep it at 85-90°C for 3 hours , The acid gas produced during the reaction process is absorbed into dilute acid water by the water in the acid gas absorption tower, which can be returned to dissolve copper tellurium slag after being concentrated. After the copper and tellurium slag is dissolved, air is blown into the ...