A method for resource utilization of tin-rich slag blown during pyrometallurgical smelting of jamesonite

Abstract

The present invention belongs to the technical field of comprehensive utilization of metallurgical resources, and provides a method for resource utilization of tin-rich converting slag. A method for resource utilization of tin-rich converting slag uses the tin-rich converting slag obtained after pyrometallurgical smelting of jamesonite as raw material. Through the alkali fusion-sulfidation method, due to the difference in solubility of lead, tin, and antimony sulfides in (NH4)S2 solution, tin can be separated separately, and lead and tin are converted into sulfide precipitates and returned to the reduction smelting step. After filtration, hydrochloric acid is added to the tin-rich solution at a certain temperature to adjust the pH so that SnS2 precipitates and separates out from the solution. The obtained SnS2 can be directly used as the anode material of a lithium-ion battery. The purpose of the present invention is to separate tin from tin-rich converting slag by a short-process method for resource utilization, enabling the converting slag to re-participate in the smelting cycle and achieving efficient utilization of resources.

Description

Technical Field

[0001] The present invention relates to the technical field of comprehensive utilization of metallurgical resources, and particularly relates to a method for resource utilization of tin-rich slag blown from jamesonite in pyrometallurgy. Background Art

[0002] In the pyrometallurgical process of jamesonite, a lead-antimony-tin composite slag will be produced after the intermediate product lead-antimony alloy is oxidized and blown. The main components are oxides of Sb, Pb, and Sn. The conventional treatment method is to return it to the reduction smelting or store it. When the slag is returned to the reduction smelting step, the accumulated impurities therein will reduce the direct recovery rate of antimony, and tin will be enriched during continuous cycling, forming another form of "tin ore". If it can be treated for resource utilization, not only can the extraction efficiency of Sb in the reduction smelting step be improved, but also the utilization level of minerals and the economic benefits of enterprises can be improved.

[0003] The conventional method for separating tin is to combine various separation methods such as blowing, smelting, and vacuum distillation to achieve the step-by-step separation and purification of tin. Specifically, in CN20110335170.1, dilute acid is used to purify tin smelting fumes to obtain tin-rich slag, and then an electric furnace is used for further smelting to obtain a tin-lead alloy. Subsequently, after refining, high-temperature vacuum distillation is used to obtain crude tin and crude lead. In CN202210694201.0, waste copper-nickel-tin alloy is subjected to suspension electrolysis, and then alkali solution hydrolysis is used to precipitate tin. After calcination, tin dioxide can be obtained. However, the above methods have a complex process system and high energy consumption, resulting in an increase in recovery costs and a decrease in economic benefits.

[0004] This patent designs a short process to efficiently separate tin from the slag, and uses the solubility difference of sulfides of tin, antimony, and lead in (NH4)2S solution to achieve targeted extraction of tin, so that the lead-antimony slag can return to the reduction smelting step after impurity removal. At the same time, the precipitated SnS2 can be used as the anode material of a lithium-ion battery to realize the resource utilization of the blown slag. This patent aims to effectively extract and materialize the tin in the slag phase through a short process, restore the recycling of the blown slag in the reduction smelting, improve the direct recovery rate of antimony, and realize the resource utilization of the tin-rich slag. Summary of the Invention

[0005] Aiming at the problem of enrichment of impurity tin in the blown slag during the pyrometallurgical process of jamesonite, the present invention takes the tin-rich slag as the object and adopts the method of alkali melting-sulfidation. By using the solubility difference of sulfides of tin, antimony, and lead in (NH4)2S solution, targeted extraction of tin is achieved. The precipitated SnS2 can be used as the anode material of a lithium-ion battery to realize resource utilization, and the blown slag can return to the reduction smelting step normally after impurity removal.

[0006] To achieve the purpose, the present invention adopts the following technical solutions:

[0007] A method for resource utilization of tin-rich slag from pyrometallurgical smelting of jamesonite, comprising the following steps:

[0008] (1) Mix an appropriate amount of NaOH and NaNO3 into the tin-rich slag for alkali melting treatment, converting lead, tin, and antimony into their corresponding metal basic salts;

[0009] (2) Add an appropriate amount of (NH4)2S solution to the roasted calcine, adjust the pH with ammonia water, control the temperature and react for a period of time, then filter to obtain the leaching solution of (NH4)2[SnS3] and the sulfide precipitate of lead and antimony, and the lead and antimony are returned to the reduction smelting step.

[0010] (3) Moderately adjust the pH and temperature of the leaching solution with hydrochloric acid to precipitate SnS2.

[0011] (4) The precipitated SnS2 is washed with dilute hydrochloric acid in multiple stages and then dried, and directly used as the negative electrode material of a lithium-ion battery.

[0012] Further, in step (1), the roasting temperature is 300 - 600 °C, the roasting time is 1 - 5 h, the mass ratio of the slag to NaOH is 1:0.2 - 0.5, and the mass ratio of NaOH to NaNO3 is 1:0.1 - 0.3.

[0013] Further, in step (2), the leaching pH is controlled at 8 - 12, the liquid-solid ratio is 2 - 10 mL:1 g, the leaching time is 1 - 5 h, and the leaching temperature is 30 - 70 °C.

[0014] Further, in step (3), the pH adjustment range is 4 - 6, and the temperature range is 40 - 80 °C.

[0015] The beneficial effects of the present invention are as follows: This patent designs a short process for tin extraction, utilizes the solubility differences of sulfides of tin, antimony, and lead in (NH4)2S solution to achieve targeted extraction of tin, enabling the lead-antimony slag to be recycled back to the reduction smelting step after impurity removal. At the same time, the precipitated SnS2 can be used as the negative electrode material of a lithium-ion battery, realizing the resource utilization of the blowing slag. Compared with conventional separation technologies, the process is shorter and the efficiency is higher, achieving targeted resource utilization. Description of the Drawings

[0016] Figure 1 Process flow chart of alkali melting and sulfide leaching for recovering tin-rich slag

[0017] Figure 2 Cycling performance graph of SnS2 as the negative electrode material of a lithium-ion battery Detailed Embodiments

[0018] Example 1

[0019] Mix 2g NaOH and 0.5g NaNO3 into 5g tin-rich slag and place it in a porcelain crucible. Roast it in a box-type resistance furnace at 400℃ for 2h. After the reaction is completed, take out the roasted sand. Prepare a 1M (NH4)2S solution with a pH of 9. Add 40mL of the prepared (NH4)2S solution to the roasted sand, heat it to 60℃ moderately, react for 3h, filter, and obtain the (NH4)2[SnS3] leachate. Gradually add dilute hydrochloric acid to adjust the pH to 5, control the temperature to 70℃, gradually precipitate SnS2, filter, wash it with dilute hydrochloric acid 2 to 3 times, and dry it at 80℃. The precipitate obtained in the sulfidation step is directly returned to the reduction smelting step.

[0020] Weigh 0.08 g of the product prepared above, 0.01 g of C45 (conductive agent), and 0.01 g of PVDF (binder), grind them thoroughly, add an appropriate amount of NMP solution, mix the slurry evenly, and then draw the slurry on copper foil to make sheets. After vacuum drying at 120°C, cut them into discs with a diameter of 12 mm, and assemble them in a glove box with an argon atmosphere, using metallic lithium sheets as counter electrodes, 1 M LiPF6 solution (solvent EC:DMC volume ratio is 1:1 2wt.%VC) as electrolyte, and polypropylene / polyethylene / polypropylene triple sandwich film (PP / PE / PP) as diaphragm to assemble into Celgard 2325 button cells.

[0021] Example 2

[0022] Mix 2.5g NaOH and 0.6g NaNO3 into 5g tin-rich slag and place it in a porcelain crucible. Roast it in a box-type resistance furnace at 600℃ for 3h. After the reaction is completed, take out the roasted sand. Prepare a 0.8M (NH4)2S solution with a pH of 10. Add 50mL of the prepared (NH4)2S solution to the roasted sand, heat it to 60℃ moderately, react for 4h, filter, and obtain the (NH4)2[SnS3] leachate. Gradually add dilute hydrochloric acid to adjust the pH to 4, control the temperature to 70℃, gradually precipitate SnS2, filter, wash it with dilute hydrochloric acid 2 to 3 times, and dry it at 80℃ after filtering. The precipitate obtained in the sulfidation step is directly returned to the reduction smelting step.

[0023] Weigh 0.08 g of the product prepared above, 0.01 g of C45 (conductive agent), and 0.01 g of PVDF (binder). After thorough grinding, add an appropriate amount of NMP solution. After uniform slurry mixing, doctor blade coating is carried out on copper foil. After drying at 120 °C under vacuum, it is cut into circular pieces with a diameter of 12 mm. Assembly is carried out in a glove box under an argon atmosphere. A lithium metal sheet is used as the counter electrode, 1 M LiPF6 solution (the solvent EC:DMC volume ratio is 1:1, 2 wt.% VC) is used as the electrolyte, and a polypropylene / polyethylene / polypropylene triple-layer film (PP / PE / PP) is used as the separator to assemble a Celgard 2325 type button cell.

Claims

1. A method for resource utilization of tin-rich slag from pyrometallurgical smelting of jamesonite, characterized in that, It includes the following steps: (1) Mix an appropriate amount of NaOH and NaNO3 into the tin-rich slag for alkali fusion roasting treatment, and lead, tin, and antimony are all converted into corresponding metal basic salts; (2) Add an appropriate amount of (NH4)2S solution to the roasted calcine, adjust the pH with ammonia water, control the temperature and react for a period of time, then filter to obtain the (NH4)2[SnS3] leaching solution and the sulfide precipitates of lead and antimony, and the lead and antimony are returned to the reduction smelting step; (3) Moderately adjust the pH and temperature of the leaching liquid with hydrochloric acid to precipitate SnS2 in the form of a precipitate; (4) The precipitated SnS2 is washed with dilute hydrochloric acid in multiple stages and then dried, and directly used as the anode material for lithium-ion batteries.

2. The method for resource utilization of tin-rich slag from pyrometallurgical smelting of jamesonite according to claim 1, characterized in that, In step (1), the roasting temperature is 300-600 °C, the roasting time is 1-5 h, the mass ratio of the slag to NaOH is 1:0.2-0.5, and the mass ratio of NaOH to NaNO3 is 1:0.1-0.

3.

3. The method for resource utilization of tin-rich slag from pyrometallurgical smelting of jamesonite according to any one of claims 1 to 2, characterized in that, In step (2), the leaching pH is controlled at 8-12, the liquid-solid ratio is 2-10 mL:1 g, the leaching time is 1-5 h, the leaching temperature is 30-70 °C, and the concentration of (NH4)2S is 0.5-2 M.

4. The method for resource utilization of tin-rich slag from pyrometallurgical smelting of jamesonite according to any one of claims 1 to 3, characterized in that, In step (3), the pH adjustment range is 4-6, and the temperature range is 40-80 °C.

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