CN-120843822-B - Method for separating and recovering copper, indium, gallium and selenium from waste solar film batteries

Abstract

The application belongs to the field of resource regeneration, and particularly relates to a method for separating and recovering copper, indium, gallium and selenium from waste solar film batteries. The application realizes the high-quality conversion and purification of all valuable elements in the waste solar film batteries to the oxides thereof by carrying out the oxidation roasting, deep eutectic leaching, extraction and back extraction on the waste solar film batteries. The method has a simple process route, realizes high-selectivity extraction of indium by utilizing the synergistic effect of the deep eutectic solvent and P204, and simultaneously realizes effective recovery of valuable elements such as copper, selenium and the like. The recovered oxide can be widely applied to strategic emerging industries such as semiconductors, photovoltaics, aerospace, military and the like.

Inventors

• ZHANG XIAOGUANG
• ZHAO HANG
• TANG YUCHENG

Assignees

• 北京工业大学

Dates

Publication Date

20260508

Application Date

20250723

Claims (4)

1. 1. The method for separating and recovering copper, indium, gallium and selenium from waste solar thin film batteries is characterized by comprising the following steps of: (1) Roasting the waste solar film batteries in a tube furnace to obtain roasting slag and volatile gas condensation product selenium oxide, wherein the roasting temperature is 800-1000 ℃ and the roasting time is 2-4 hours; (2) The deep eutectic configuration, namely uniformly mixing a hydrogen bond acceptor, a hydrogen bond donor and deionized water to obtain a deep eutectic solvent; (3) Wet leaching, namely carrying out wet leaching on the roasting slag obtained in the step (1) by using the deep eutectic solvent obtained in the step (2) to obtain deep eutectic leaching liquid; (4) Extracting the deep eutectic leaching solution obtained in the step (3) to obtain deep eutectic raffinate containing copper and gallium and an indium-loaded organic phase; (5) Carrying out indium stripping, namely carrying out stripping on the loaded indium organic phase obtained in the step (4) to obtain an empty indium organic phase and indium chloride solution, and returning the empty indium organic phase to an indium extraction process, wherein hydrochloric acid is used as a stripping agent, the concentration of the hydrochloric acid is 3.0mol/L, the stripping O/A phase ratio is 1:1, the stripping temperature is 25 ℃, the stripping time is 5min, and the stripping stage number is 1; (6) Copper extraction, namely extracting the deep eutectic raffinate containing copper and gallium obtained in the step (4) to obtain the deep eutectic raffinate containing gallium and a loaded copper organic phase; (7) Copper back extraction, namely carrying out back extraction on the loaded copper organic phase obtained in the step (6) to obtain an empty copper organic phase and a copper sulfate solution, wherein the empty copper organic phase returns to a copper extraction procedure, sulfuric acid is used as a back extraction agent, the concentration of the sulfuric acid is 2.0mol/L, the back extraction O/A phase ratio is 1:1, the back extraction temperature is 25 ℃, the back extraction time is 5min, and the back extraction stage number is 1; (8) Precipitating and roasting, namely precipitating the deep eutectic raffinate containing gallium obtained in the step (6) to obtain a precipitation solution and precipitation slag, carrying out centralized treatment on the precipitation solution, roasting the precipitation slag to obtain a gallium oxide product, carrying out pH adjustment on the indium chloride solution and the copper sulfate solution obtained in the steps (5) and (7), obtaining different precipitates after adjustment, and respectively obtaining the indium oxide product and the copper oxide product after roasting; In the step (2), the hydrogen bond acceptor is choline chloride or polyethylene glycol, the hydrogen bond donor is oxalic acid, formic acid, lactic acid, citric acid or tartaric acid, the molar ratio of the hydrogen bond acceptor to the hydrogen bond donor is 3:1-1:3, the water content is 20% -60%, the temperature is 50-90 ℃, the stirring speed is 400r/min, and the stirring time is 30min.
2. 2. The method according to claim 1, wherein the leaching time in the step (3) is 6-10 h, the leaching temperature is 50-90 ℃, and the solid ratio of the leaching solution is 40-80 mL/g.
3. 3. The method of claim 1, wherein in the step (4), the extractant is P204, the kerosene is used as a diluting solvent, the volume ratio of P204 to kerosene is 1:1-1:5, the extraction O/a ratio is 1:1-1:4, the extraction temperature is 20-40 ℃, the extraction time is 3-5 min, and the extraction stage number is 1-4.
4. 4. The method of claim 1, wherein in the step (6), the extractant is Lix84, the diluting solvent is kerosene, the volume ratio of Lix84 to kerosene is 1:1-1:5, the extraction O/a phase ratio is 1:1-1:4, the extraction temperature is 20-40 ℃, the extraction time is 5-10 min, and the extraction stage number is 1-5.

Description

Method for separating and recovering copper, indium, gallium and selenium from waste solar film batteries Technical Field The invention belongs to the field of resource regeneration, and particularly relates to a method for separating and recovering copper, indium, gallium and selenium from waste solar film batteries. Background CIGS (CuInGaSe 2) is used as a core material of a new-generation thin film solar cell, has the advantages of strong light absorption capacity, good power generation stability, high conversion efficiency, long power generation time in daytime, high power generation quantity, low production cost, short energy recovery period and the like, and is widely paid attention to. As the first commercial CIGS assembly enters a typical scrap period (8-12 years), the production of spent batteries increases exponentially. However, indium and gallium belong to IIIA group elements, the radius of ions is close, and the charge density is similar, so that the traditional separation process has three technical bottlenecks of selectivity, high co-extraction rate and mutual exclusion of indium and gallium recovery rate, and the recycling efficiency is severely restricted. Therefore, breaking through the indium gallium deep separation technology is an urgent need to achieve efficient CIGS recovery. In the chinese patent application CN102296178a, a method for recovering copper, indium, gallium and selenium is disclosed, which mainly uses a mixed solution of hydrochloric acid and hydrogen peroxide to dissolve metal powder containing copper, indium, gallium and selenium, and after separating selenium using hydrazine, copper is replaced by indium metal. And finally, separating indium from gallium by combining the supported liquid film with the dispersed strip liquor. Chinese patent application publication No. CN103184388a discloses a copper indium gallium diselenide recovery method. The method comprises the steps of firstly breaking the copper indium gallium diselenide thin film solar panel into fragments, then placing the fragments into a sulfuric acid and hydrogen peroxide mixed solution system with a specific temperature, and soaking for a specified time to obtain a leaching solution. Then, the indium, gallium and selenium elements are recovered from the leaching solution through extraction, back extraction, electrolysis and other processes. U.S. patent No. US5779877 discloses a method for recycling copper indium selenium solar cell waste. The method mainly comprises crushing, nitric acid leaching, electrolytic separation of copper, selenium and indium by two electrodes, evaporation and decomposition to obtain a mixture of oxides of indium and zinc, and oxidative distillation to separate copper and selenium. Patent CN201610039562 discloses a method for recovering copper indium gallium selenide material, which mainly comprises the steps of sulfatizing roasting, sulfuric acid dissolving, extracting electrolytic copper metal, producing gallium hydroxide precipitate, replacing indium and the like. In the prior art, a large amount of acid reagent is used in the roasting and leaching links, so that acid gas pollution is easily caused. Meanwhile, the extracting agent used in indium extraction produces a co-extraction phenomenon on gallium, so that the separation of indium and gallium is difficult, and the recovery rate of indium and gallium is reduced. On the other hand, the treatment method for replacing copper by indium is too high in production cost. In order to solve the defects in the prior art, the invention aims to provide the recycling method of the copper indium gallium selenide material, which can reduce environmental pollution, has high recycling rate and lower production cost. Disclosure of Invention In order to solve the problems, the invention provides a method for separating and recovering copper, indium, gallium and selenium from waste solar film batteries. According to the method, selenium is recovered through an oxidation roasting process, acid and alkali are not required to be added in the process, and the problems of selenide volatilization and acid-containing waste gas emission in the traditional recovery method are effectively solved. And then, the leaching is carried out by adopting a recyclable deep eutectic reagent, so that the leaching effect is excellent and the cost is low. In the leaching solution treatment link, the high-efficiency separation of indium and gallium is successfully realized through the selectivity of P204, and the co-extraction problem in the extraction process is solved, so that the recovery rate of indium and gallium is remarkably improved. The recovered high-purity indium oxide, gallium oxide, selenium oxide and copper oxide products can be widely applied to strategic emerging industries such as semiconductors, photovoltaics, aerospace, military and the like. The process has the remarkable advantages of simple process, high-efficiency indium-gallium separation, excel