Recovery method of low-content precious metal platinum solution

Abstract

The invention discloses a recovery method of a low-content precious metal platinum solution, and belongs to the field of recycling of precious metal resources. The method comprises the following steps: mixing a low-content precious metal platinum solution with an activated carbon adsorbent, and carrying out adsorption reaction in an electrostatic field to form a platinum-loaded adsorbent; and then adding the platinum-loaded adsorbent into an aqueous solution of thiourea and sulfuric acid, and desorbing in an ultrasonic field to realize desorption and recovery of platinum. Aiming at a low-content precious metal platinum solution, a coupling process of electrostatic field enhanced adsorption and ultrasonic enhanced desorption is utilized, so that the adsorption driving force of activated carbon to platinum ions is enhanced, the adsorption efficiency and the adsorption capacity are improved, and the traditional adsorption efficiency bottleneck is broken through. Moreover, platinum ions are effectively promoted to be quickly desorbed from the surface of the adsorbent, the desorption time is greatly shortened, and the recovery efficiency is improved. The whole adsorption-desorption process is completed under the low-temperature condition, compared with a traditional high-temperature process, the energy consumption is remarkably reduced, and good economical efficiency is achieved.

Description

Technical Field

[0001] This invention relates to a method for recovering a low-content platinum solution, belonging to the field of precious metal resource recycling. Background Technology

[0002] In modern industry, the precious metal platinum is widely used in chemical, electronics, and automotive fields. However, industrial production processes generate large quantities of low-content platinum solutions, which are difficult to recover. Traditional activated carbon adsorption methods suffer from low adsorption efficiency and small adsorption capacity, making them unsuitable for high-efficiency recovery. Chemical precipitation and solvent extraction methods, on the other hand, are complex, costly, and environmentally problematic, making them unsuitable for low-content platinum solutions. Therefore, there is an urgent need to develop an efficient, economical, and environmentally friendly platinum recovery technology to achieve the recycling of platinum resources, reduce dependence on primary platinum resources, and has significant economic and environmental implications. Summary of the Invention

[0003] To overcome the problems in the prior art, the present invention proposes a method for recovering low-content platinum metal solutions.

[0004] To achieve the above objectives, the present invention is implemented through the following technical solution: A method for recovering a low-content platinum solution includes the following steps: (1) A low-content platinum metal solution is mixed with activated carbon adsorbent and placed in an electrostatic field to carry out an adsorption reaction to form a platinum-loaded adsorbent. (2) Platinum-loaded adsorbent is added to an aqueous solution of thiourea and sulfuric acid and placed in an ultrasonic field for desorption to achieve platinum desorption and recovery.

[0005] Preferably, the platinum content in the low-content precious metal platinum solution is 7-12 mg / L or higher.

[0006] Recovery of low-content platinum is challenging, and traditional methods such as extraction and ion exchange are costly and economically inefficient. Furthermore, traditional adsorption processes consume large amounts of adsorbent and require specific temperatures to accelerate mass transfer and improve adsorption efficiency. This invention employs a low-temperature physical field-enhanced adsorption process, which effectively reduces energy consumption during adsorption, and the low-power electric field enhancement achieves better adsorption results.

[0007] Preferably, the low-content platinum solution also contains aluminum ions, with an aluminum concentration of 20-40 g / L.

[0008] Preferably, the solid-liquid ratio of the activated carbon adsorbent to the low-content platinum metal solution is 1-3 g / L.

[0009] Preferably, the electrostatic voltage of the electrostatic field is 10-25kV, the adsorption time is 20-40min, and the adsorption temperature is 20-30℃.

[0010] Preferably, the concentration of thiourea in the aqueous solution of thiourea and sulfuric acid is 0.1-0.3 mol / L, and the concentration of sulfuric acid is 0.05-0.15 mol / L.

[0011] Preferably, the power of the ultrasonic field is 100-150W; the desorption temperature is 20-30℃; and the time is 30-50min.

[0012] Preferably, the liquid-to-solid ratio of the aqueous solution of thiourea and sulfuric acid to the platinum-loaded adsorbent is 5-10:1 mL / g.

[0013] The beneficial effects of this invention are as follows: This invention targets low-content platinum solutions and utilizes a coupled process of electrostatically enhanced adsorption and ultrasonically enhanced desorption. On one hand, it enhances the adsorption driving force of activated carbon for platinum ions, improving adsorption efficiency and capacity, thus overcoming the bottleneck of traditional adsorption efficiency. On the other hand, it effectively promotes the rapid desorption of platinum ions from the adsorbent surface, significantly shortening the desorption time and improving recovery efficiency. The entire adsorption-desorption process is completed under low-temperature conditions, significantly reducing energy consumption compared to traditional high-temperature processes, demonstrating good economic efficiency. Furthermore, it is simple to operate and easy to scale up for continuous industrial production, providing a reliable technical path for the efficient recovery of low-content platinum solutions and possessing broad market application prospects. Attached Figure Description

[0014] Figure 1 This is a process flow diagram of the method for recovering low-content precious metal platinum solution according to the present invention.

[0015] Figure 2 The graph shows the relationship between platinum adsorption efficiency and static voltage in Example 2.

[0016] Figure 3 The graph shows the platinum adsorption rate of the activated carbon adsorbent after 5 regeneration cycles in Example 1. Detailed Implementation

[0017] The present invention will be further described in detail below with reference to specific embodiments, but the scope of protection of the present invention is not limited thereto.

[0018] Example 1 like Figure 1 As shown, a method for recovering a low-content platinum solution includes the following steps: A low-content platinum solution (7 mg / L) from a precious metal production company was taken. Activated carbon adsorbent was added to the platinum solution, and then the solution was placed in an electrostatic field with a static voltage of 15 kV for 30 min for adsorption. The concentration of the activated carbon adsorbent was 2 g / L, and the adsorption temperature was 25℃. After adsorption, the platinum adsorbent adsorption efficiency reached 95.55%, yielding a platinum-loaded adsorbent. Subsequently, the platinum-loaded adsorbent was placed in an ultrasonic field, and desorption was performed by adding an aqueous solution of 0.2 mol / L thiourea and 0.1 mol / L sulfuric acid. The ultrasonic power was 120 W, the liquid-to-solid ratio was 10 mL:1 g, the desorption temperature was 20℃, and the desorption time was 40 min. The platinum recovery rate after desorption reached 95.8%.

[0019] Cyclic experiment: After washing the surface of the desorbed activated carbon with deionized water to remove residual eluent, the activated carbon is regenerated and then the next adsorption and desorption process is carried out.

[0020] according to Figure 3 It can be seen that the desorbed activated carbon adsorbent in Example 1 can be reused, and the adsorption rate of platinum reaches more than 90% after 5 cycles. Therefore, the desorbed activated carbon adsorbent can be reused.

[0021] Example 2 A method for recovering a low-content platinum solution includes the following steps: A low-content platinum solution (platinum content 12 mg / L) from a precious metal production enterprise was taken. Activated carbon adsorbent was added to the platinum solution, and then the solution was placed in an electrostatic field with a static voltage of 12.5 kV for 30 min for adsorption. The concentration of activated carbon adsorbent was 2 g / L, and the temperature was 25℃. The platinum adsorption efficiency reached 91.55%, yielding a platinum-loaded adsorbent. Subsequently, the platinum-loaded adsorbent was placed in an ultrasonic field and a composite desorption system for desorption. Desorption was performed using an aqueous solution of 0.15 mol / L thiourea and 0.1 mol / L sulfuric acid, with an ultrasonic power of 130 W, a liquid-to-solid ratio of 8 mL:1 g, and a temperature of 28℃ for 30 min. The platinum recovery rate was 93.1%.

[0022] Example 3 A method for recovering a low-content platinum solution includes the following steps: A low-content platinum solution (9 mg / L) was taken from a precious metal production enterprise. Activated carbon adsorbent was added to the platinum solution, and then the solution was placed in an electrostatic field with a static voltage of 10 kV for 35 min for adsorption. The concentration of activated carbon adsorbent was 3 g / L, and the temperature was 28℃. The platinum adsorption efficiency reached 93.0%, yielding a platinum-loaded adsorbent. Subsequently, the platinum-loaded adsorbent was placed in an ultrasonic field and a composite desorption system for desorption. The desorption system used was a composite desorption system of 0.25 mol / L thiourea and 0.12 mol / L sulfuric acid aqueous solution. The ultrasonic power was 140 W, the liquid-to-solid ratio was 5 mL:1 g, and the temperature was 30℃ for 50 min. The platinum recovery rate was 94.5%.

[0023] Example 4 The only difference between the low-content platinum solution recovery method in this embodiment and that in Example 1 is that the static voltage is 5, 10, 20, or 25 kV.

[0024] according to Figure 2 It can be seen that the adsorption rate of platinum by activated carbon increases with the increase of static voltage.

[0025] Comparative Example 1 A method for recovering a low-content platinum solution includes the following steps: A low-content platinum solution (7 mg / L) from a precious metal production company was taken. Activated carbon adsorbent (2 g / L) was added to the platinum solution at an adsorption temperature of 25℃. The adsorption efficiency of platinum after adsorption was 89.27%, yielding a platinum-loaded adsorbent. Subsequently, the platinum-loaded adsorbent was placed in an ultrasonic field, and a 0.2 mol / L thiourea and 0.1 mol / L sulfuric acid aqueous solution was added for desorption. The ultrasonic power was 120 W, the liquid-to-solid ratio was 10 mL:1 g, the desorption temperature was 25℃, and the desorption time was 40 min. The platinum recovery rate after desorption reached 93.97%, and the desorbed activated carbon adsorbent could be reused.

[0026] Comparative Example 2 A method for recovering a low-content platinum solution includes the following steps: A low-content platinum solution (7 mg / L) from a precious metal production company was taken. Activated carbon adsorbent was added to the platinum solution, and then the solution was placed in an electrostatic field with a static voltage of 15 kV for 30 min for adsorption. The concentration of the activated carbon adsorbent was 2 g / L, and the adsorption temperature was 25℃. After adsorption, the platinum adsorption efficiency reached 95.28%, yielding a platinum-loaded adsorbent. Subsequently, the platinum-loaded adsorbent was added to an aqueous solution of 0.2 mol / L thiourea and 0.1 mol / L sulfuric acid for desorption, with a liquid-to-solid ratio of 10 mL:1 g, a desorption temperature of 25℃, and a desorption time of 40 min. The platinum recovery rate after desorption reached 74.37%. Figure 2It can be seen that the adsorption efficiency of activated carbon for platinum after five cycles is approximately 85%.

[0027] Comparative Example 3 A method for recovering a low-content platinum solution includes the following steps: A low-content platinum solution (7 mg / L) from a precious metal production company was taken. Activated carbon adsorbent was added to the platinum solution, and then the solution was placed in an electrostatic field with a static voltage of 15 kV for 30 min for adsorption. The concentration of the activated carbon adsorbent was 2 g / L, and the adsorption temperature was 25℃. After adsorption, the platinum adsorption efficiency reached 95.32%, yielding a platinum-loaded adsorbent. Subsequently, the platinum-loaded adsorbent was placed in an ultrasonic field, and a 0.1 mol / L sulfuric acid system was added for desorption. The ultrasonic power was 120 W, the liquid-to-solid ratio was 10 mL:1 g, the desorption temperature was 25℃, and the desorption time was 40 min. The platinum recovery rate after desorption reached 80.21%, and the adsorption efficiency of activated carbon for platinum after five cycles was approximately 80%.

[0028] Comparative Example 4 A method for recovering a low-content platinum solution includes the following steps: A low-content platinum solution (7 mg / L) from a precious metal production company was taken. Activated carbon adsorbent was added to the platinum solution, and then the solution was placed in an electrostatic field with a static voltage of 15 kV for 30 min for adsorption. The concentration of the activated carbon adsorbent was 2 g / L, and the adsorption temperature was 25℃. After adsorption, the platinum adsorption efficiency reached 95.64%, yielding a platinum-loaded adsorbent. Subsequently, the platinum-loaded adsorbent was placed in an ultrasonic field, and a 0.2 mol / L thiourea system was added for desorption. The ultrasonic power was 120 W, the liquid-to-solid ratio was 10 mL:1 g, the desorption temperature was 25℃, and the desorption time was 40 min. The platinum recovery rate after desorption reached 84.17%, and the adsorption efficiency of activated carbon for platinum after five cycles was approximately 85%.

[0029] Finally, it should be noted that the above preferred embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail through the above preferred embodiments, those skilled in the art should understand that various changes can be made to it in form and detail without departing from the scope defined by the claims of the present invention.

Claims

1. A method for recovering a low-content platinum solution, characterized in that: Includes the following steps: (1) A low-content platinum metal solution is mixed with activated carbon adsorbent and placed in an electrostatic field to carry out an adsorption reaction to form a platinum-loaded adsorbent. (2) Platinum-loaded adsorbent is added to an aqueous solution of thiourea and sulfuric acid and placed in an ultrasonic field for desorption to achieve platinum desorption and recovery.

2. The method for recovering a low-content platinum solution according to claim 1, characterized in that: The concentration of platinum in the low-content platinum solution is 7-12 mg / L or higher.

3. The method for recovering a low-content platinum solution according to claim 1, characterized in that: The solid-liquid ratio of the activated carbon adsorbent to the low-content platinum metal solution is 1-3 g / L.

4. The method for recovering a low-content platinum solution according to claim 1, characterized in that: The electrostatic voltage of the electrostatic field is 10-25kV, the adsorption time is 20-40min, and the adsorption temperature is 20-30℃.

5. The method for recovering a low-content platinum solution according to claim 1, characterized in that: The concentration of thiourea in the aqueous solution of thiourea and sulfuric acid is 0.1-0.3 mol / L, and the concentration of sulfuric acid is 0.05-0.15 mol / L.

6. The method for recovering a low-content platinum solution according to claim 1, characterized in that: The power of the ultrasonic field is 100-150W; the desorption temperature is 20-30℃, and the time is 30-50min.

7. The method for recovering a low-content platinum solution according to claim 1, characterized in that: The liquid-solid ratio of the aqueous solution of thiourea and sulfuric acid to the platinum-loaded adsorbent is (5-10) mL:1 g.

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