CN109930010B - A kind of method for removing organic matter in wet zinc solution - Google Patents

Abstract

The invention relates to a method for removing organic matter in a zinc hydrometallurgy solution, belonging to the technical field of chemical metallurgy. Stir the hydrometallurgical zinc solution containing organics, gradually cool down to –20°C~10°C, react for 10min~60min, use organics to induce nucleation to form crystalline precipitates containing organics, after the reaction, use centrifugal filtration liquid-solid After separating the crystal precipitation containing organic matter, a zinc sulfate solution from which organic matter has been removed is obtained. The method is to use the large specific surface area of macromolecular organic matter and the difference between the properties of small molecular organic matter and zinc sulfate solution in a cooling reactor, and through the induced nucleation of organic matter, the reaction forms crystalline precipitation containing organic matter, and then through solidification The method of liquid separation realizes the removal of organic matter and obtains a qualified zinc sulfate solution. The invention has the advantages of simple process, easy operation and high removal efficiency of organic matter.

Description

A kind of method for removing organic matter in wet zinc solution

technical field

The invention relates to a method for removing organic matter in a zinc hydrometallurgy solution, belonging to the technical field of chemical metallurgy.

Background technique

The excessive organic content in the zinc sulfate solution produced by the zinc hydrometallurgy will have an adverse effect on the solution purification and electrowinning process, resulting in an increase in the consumption of zinc powder in the purification process, a decrease in the current efficiency and an increase in power consumption in the zinc electrowinning process. Cathode zinc and lead exceeding the standard and other hazards. Therefore, how to remove organic matter in zinc sulfate solution has always been an important issue in the zinc hydrometallurgy industry.

The methods for removing organic matter in solution include: (1) Activated carbon adsorption method. The porous structure of activated carbon provides a large surface area and has a strong adsorption capacity for organic matter. The organic matter in the solution is removed by adsorption, and steam activation and regeneration can be used after reaching the breakthrough capacity. (2) Air flotation method. The air flotation method uses the hydrophobic properties of the organic matter in the solution to blow a large number of fine air bubbles into the solution, so that the organic matter is adsorbed on the fine air bubbles, and the organic matter floats together by the buoyancy of the bubbles itself. A three-phase foam layer composed of air bubbles and hydrated organic matter is formed on the liquid surface, and the foam layer is separated from the solution body to achieve the purpose of removing organic matter. (3) Liquid membrane filtration method. By constructing a filter membrane, the organic matter and the solution are separated by using the deficit of different concentrations. (4) Ultrasonic demulsification and degreasing. The tiny oil droplets in the solution vibrate together with the medium under the action of ultrasonic waves, but the examples of different sizes have different vibration speeds. Separated from solution. (5) Ozone oxidation and photooxidation. Ozone oxidation is the use of the strong oxidative properties of ozone to decompose organic matter. Photooxidation is the use of oxidants to generate free radicals with strong oxidizing ability under light radiation to decompose organic pollutants.

The patent with the patent application number of "201810707518.7" discloses a method for photo-oxidative removal of organic matter in wet smelting zinc sulfate solution. Oxidation reaction to achieve the decomposition and removal of organic matter.

The patent with the patent application number of "201510456786.2" discloses a method for applying supergravity and ozone to strengthen the removal of organic matter in zinc sulfate solution. The method is to add oxygen and atomize the zinc sulfate solution after heating, and the atomized zinc sulfate solution In the hypergravity release equipment fully reacts with ozone to enhance. The oxygen and solution circulation of the hypergravity field generator is then maintained to obtain a qualified zinc sulfate solution for removing organic matter.

Although the above method can remove the organic matter in the zinc sulfate solution, it mainly removes the soluble organic matter with a smaller molecular weight. For the organic matter with a large molecular weight, such as bone glue, gelatin, beef glue, etc., the removal effect is poor, and there are complicated operations. , large equipment investment and other shortcomings. Therefore, the development of a high-efficiency, simple and feasible new method for removing organics from zinc sulfate solution is still a technical problem that needs to be further solved in the zinc hydrometallurgy industry.

SUMMARY OF THE INVENTION

In order to overcome the deficiencies of the prior art, the present invention provides a method for removing organic matter in zinc sulfate solution. The method is to use the large specific surface area of macromolecular organic matter and the difference between the properties of small molecular organic matter and zinc sulfate solution in a cooling reactor, and through the induced nucleation of organic matter, the reaction forms crystalline precipitation containing organic matter, and then through solidification The method of liquid separation realizes the removal of organic matter and obtains a qualified zinc sulfate solution. The invention has the advantages of simple process, easy operation and high removal efficiency of organic matter.

In order to achieve the above object, the present invention realizes through the following technical solutions:

A method for removing organic matter in a hydrometallurgical zinc solution, the hydrometallurgical zinc solution containing organic matter is stirred, and the temperature is gradually lowered to -20 ℃ ~ 10 ℃, and the reaction is performed for 10 min to 60 min, and the organic matter is used to induce nucleation. The crystalline precipitation of the organic substance, after the completion of the reaction, the liquid-solid separation of the organic substance-containing crystalline precipitation is performed by centrifugal filtration to obtain a zinc sulfate solution from which the organic substance is removed.

The organic-containing hydrometallurgical zinc solution is produced by hydrometallurgy zinc, wherein the zinc concentration is 40-155 g/L, and the solution sulfuric acid concentration is 0.01-180 g/L.

The organic matter in the organic matter-containing zinc hydrometallurgy solution is calculated as total organic carbon, and the total organic carbon is greater than 35 mg/L.

The temperature of the organic-containing hydrometallurgical zinc solution is 35°C to 65°C.

The stirring speed is 10-120 rev/min.

The specific process of the gradual cooling is as follows: at the beginning, the temperature is lowered to 25 to 30°C at a cooling rate of 1 to 2°C/min, and then to -20°C to 10°C at a cooling rate of 2 to 5°C/min. .

The beneficial effects of the invention are as follows: the method adopts a cooling reactor, utilizes the large specific surface area of macromolecular organic matter and the difference in properties between small molecular organic matter and zinc sulfate solution, and reacts to form crystals containing organic matter through the induced nucleation of organic matter Precipitation, and under the condition of rapid liquid-solid separation, the crystal precipitate containing organic is removed to obtain a qualified zinc sulfate solution. The method does not need external chemical reagents, and has the advantages of simple process, easy operation and high removal efficiency of organic matter.

Detailed ways

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

Example 1

The method for removing organic matter in the hydrometallurgical zinc solution is to mix 1000 mL of the organic matter-containing hydrometallurgical zinc solution (the organic matter-containing hydrometallurgical zinc solution from the waste electrolyte with a temperature of 38°C produced by the hydrometallurgical zinc solution, zinc The concentration is 40g/L and the concentration of sulfuric acid is 180g/L; the organic matter in the hydrometallurgical zinc solution containing organic matter is calculated as total organic carbon, and the total organic carbon is 95.3mg/L. xanthate, fatty acid and other small molecular organic compounds), placed in a cooling reactor for stirring (120 rpm), and gradually cooled to -20 °C. The temperature is 25 °C, then continue to cool down to –20 °C at a cooling rate of 2 °C/min, react for 10 min, and use organic matter to induce nucleation to form a crystalline precipitate containing organic matter. After crystal precipitation, 982 mL of zinc sulfate solution from which organic matter was removed was obtained.

The detection result is that the total organic carbon content in the zinc sulfate solution from which organic matter is removed is 18.5 mg/L, and the removal rate of organic matter is 80.9%.

Example 2

In the method for removing organic matter in a zinc hydrometallurgy solution, 1000 mL of a hydrometallurgical zinc solution containing organic matter (a hydrometallurgical zinc solution containing organic matter) is produced by hydrometallurgical zinc to produce a waste electrolyte with a temperature of 37° C. The zinc concentration It is 46g/L and the sulfuric acid concentration is 165g/L; the organic matter in the hydrometallurgical zinc solution containing organic matter is calculated as total organic carbon, and the total organic carbon is 89.1mg/L. The types of organic matter include macromolecular organics such as gelatin, lubricating oil and ethyl Small molecular organics such as xanthate, fatty acid, etc. Placed in a cooling reactor for stirring (80 rpm), and gradually cooled to -10 °C. ℃, and then continue to cool down to –10℃ at a cooling rate of 3℃/min, react for 30min, use organics to induce nucleation to form crystalline precipitates containing organics, after the reaction, use centrifugal filtration to separate liquid-solid crystalline precipitates containing organics After that, 975 mL of zinc sulfate solution from which organic matter was removed was obtained.

The detection result is that the total organic carbon content in the zinc sulfate solution from which organic matter is removed is 22.0 mg/L, and the removal rate of organic matter is 75.9%.

Example 3

In the method for removing organic matter in a hydrometallurgical zinc solution, 1000 mL of a hydrometallurgical zinc solution containing organic matter (the hydrometallurgical zinc solution containing organic matter is the pre-electrolysis solution of hydrosmelting zinc with Wendy at 35°C, and the zinc concentration is 52g/L, sulfuric acid concentration 153g/L; the organic matter in the hydrometallurgical zinc solution containing organic matter is calculated as total organic carbon, and the total organic carbon is 58.6mg/L. fatty acids and other small molecular organics). Placed in a cooling reactor for stirring (50 r/min), and gradually cooled to -5 °C. The specific process is: at the beginning, the cooling rate was reduced to 25 °C at a cooling rate of 2 °C/min, and then continued at 5 °C/min. The cooling rate was reduced to -5 °C, and the reaction was carried out for 30 min. The organic matter was used to induce nucleation to form a crystalline precipitate containing organic matter. After the reaction was completed, the crystalline precipitate containing organic matter was separated from the liquid and solid by centrifugal filtration, and 962 mL of sulfuric acid with organic matter removed was obtained. Zinc solution.

The detection result is that the total organic carbon content in the zinc sulfate solution from which organic matter is removed is 20.6 mg/L, and the removal rate of organic matter is 62.9%.

Example 4

In the method for removing organic matter in a hydrometallurgical zinc solution, 1000 mL of a hydrosmelting zinc solution containing organic matter (the hydrosmelting zinc solution containing organic matter is the purified liquid of the third stage of hydrosmelting zinc, the temperature is 65° C., the zinc concentration It is 155g/L, and the acidity of the solution is pH 5.4; the organic matter in the hydrometallurgical zinc solution containing organic matter is calculated as total organic carbon, and the total organic carbon is 35.2 mg/L. xanthate, fatty acid and other small molecular organic compounds) are placed in a cooling reactor for stirring (10 rpm), and the temperature is gradually lowered to 10 °C. ℃, then continue to cool down to 10℃ at a cooling rate of 2℃/min, react for 60min, use organics to induce nucleation to form crystalline precipitates containing organics, after the reaction is over, use centrifugal filtration to separate liquid-solid crystalline precipitates containing organics , to obtain 945 mL of zinc sulfate solution with organics removed.

The detection result is that the total organic carbon content in the zinc sulfate solution from which organic matter is removed is 21.9 mg/L, and the removal rate of organic matter is 41.2%.

The specific embodiments of the present invention have been described in detail above, but the present invention is not limited to the above-mentioned embodiments. Various changes can be made within the scope of knowledge possessed by those of ordinary skill in the art without departing from the spirit of the present invention. .

Claims (5)

1. A method for removing organic matters in a zinc hydrometallurgy solution is characterized by comprising the following steps: stirring the wet-process zinc smelting solution containing the organic matters, gradually cooling to-20-10 ℃, reacting for 10-60 min, forming crystal precipitates containing the organic matters by utilizing the induced nucleation effect of the organic matters, and after the reaction is finished, carrying out solid-liquid separation on the crystal precipitates containing the organic matters by adopting centrifugal filtration to obtain a zinc sulfate solution without the organic matters;

the specific process of gradually cooling is as follows: the temperature is reduced to 25-30 ℃ at a cooling speed of 1-2 ℃/min at the beginning, and then the temperature is reduced to-20-10 ℃ at a cooling speed of 2-5 ℃/min.

2. The method for removing organic matters from a zinc hydrometallurgy solution according to claim 1, wherein: the organic matter-containing zinc hydrometallurgy solution is produced by zinc hydrometallurgy, wherein the concentration of zinc is 40-155 g/L, and the concentration of sulfuric acid in the solution is 0.01-180 g/L.

3. The method for removing organic matters from a zinc hydrometallurgy solution according to claim 1, wherein: the organic matters in the wet zinc smelting solution containing the organic matters are calculated by total organic carbon, and the total organic carbon is more than 35 mg/L.

4. The method for removing organic matters from a zinc hydrometallurgy solution according to claim 1, wherein: the temperature of the wet-process zinc smelting solution containing the organic matters is 35-65 ℃.

5. The method for removing organic matters from a zinc hydrometallurgy solution according to claim 1, wherein: the stirring speed is 10-120 r/min.