Method for separating and recovering tungsten and cobalt from hard alloy grinding material pickle liquor

Abstract

The invention discloses a method for separating and recovering tungsten and cobalt from a hard alloy grinding material pickle liquor, which comprises the following steps: mixing a waste hard alloy grinding material with the acid liquor, reacting metal elements such as cobalt and nickel with acid to convert into soluble metal ions, and enabling cobalt metal ions and nickel metal ions to mainly exist in the pickle liquor in the form of positive ions, the alkalescent anion exchange resin mainly adsorbs anions, so that the affinity of the alkalescent anion exchange resin with cobalt and nickel cations is relatively weak; tungsten metal ions in the acid leaching solution exist in the acid leaching solution in the form of anions, such as tungstate, and the anions have strong affinity with negative electricity groups on the surface of the alkalescent anion exchange resin and are easily adsorbed by the resin; weak alkaline groups enter the solution to provide an acid environment, cobalt and nickel are prevented from being converted into hydroxides, tungsten in the pickle liquor is separated, cobalt and nickel precipitation cannot be caused, the recovery rate of tungsten is increased, and meanwhile cobalt and nickel recovery cannot be affected.

Description

Technical Field

[0001] The invention relates to the technical field of conversion and utilization of waste cemented carbide grinding material resources, and more specifically, to a method for separating and recovering tungsten and cobalt from a cemented carbide grinding material acid leaching liquid. Background Art

[0002] Waste carbide grinding materials contain a certain amount of valuable metal elements. Recycling them through certain technical means can not only improve resource utilization, but also reduce environmental pollution. At present, acid leaching is used to recover cobalt and nickel. Waste carbide grinding materials are soaked in dilute sulfuric acid or dilute hydrochloric acid solution to dissolve cobalt and nickel, but some tungsten will also enter the acid leaching solution.

[0003] In the prior art, alkali is added to the acid leaching solution to convert cobalt and nickel into hydroxides for precipitation, and tungsten is converted into tungstate and retained in the solution. However, cobalt and nickel hydroxides also contain tungsten, resulting in a low tungsten separation rate.

[0004] Therefore, it is urgent to provide a method for separating and recovering tungsten and cobalt from the acid leaching liquid of cemented carbide grinding materials to improve the separation rate of tungsten. Summary of the invention

[0005] The purpose of the present invention is to overcome the above-mentioned defects of the prior art and provide a method for separating and recovering tungsten and cobalt from the acid leaching liquid of cemented carbide grinding material, comprising the following steps:

[0006] (1) mixing the waste cemented carbide grinding material with acid solution to obtain a mixed slurry;

[0007] (2) performing solid-liquid separation on the mixed slurry to obtain an acid leaching solution and solid slag, wherein the acid leaching solution includes tungstate ions;

[0008] (3) After the pH of the acid leaching solution is adjusted to 1.0-2.5, the tungstate ions are adsorbed and separated by a weakly basic anion exchange resin, and the tungstate ions are adsorbed by the weakly basic anion exchange resin to obtain a resin loaded with tungstate ions and a cobalt-nickel solution;

[0009] (4) Desorbing the resin loaded with tungstate ions with an alkali solution to obtain the tungstate solution.

[0010] Implementing the embodiments of the present invention will have the following beneficial effects:

[0011] In this embodiment, the waste cemented carbide grinding material is mixed with the acid solution, and the metal elements such as cobalt and nickel react with the acid to be converted into soluble metal ions. 2+ ) and nickel metal ions (Ni 2+) mainly exists in the acid leaching solution in the form of cations. Since the weakly alkaline anion exchange resin mainly adsorbs anions, its affinity with cobalt and nickel cations is weak; the tungstate ions in the acid leaching solution exist in the form of anion complexes (such as tungstate WO4 2- ) exists in the acid leaching solution. The anion complex has a strong affinity with the negatively charged groups on the surface of the weakly alkaline anion exchange resin and is easily adsorbed by the resin. At the same time, cobalt and nickel will not be converted into hydroxides under acidic conditions, which not only separates tungsten from the acid leaching solution, but also does not cause cobalt and nickel precipitation, thereby improving the recovery rate of tungsten without affecting the recovery of cobalt and nickel. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0013] in:

[0014] Figure 1 The present invention provides a flow chart of a method for separating and recovering tungsten and cobalt from a carbide grinding material pickling solution. DETAILED DESCRIPTION

[0015] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0016] Reference Figure 1 The present invention discloses a method for separating and recovering tungsten and cobalt from a carbide grinding material pickling solution, comprising the following steps:

[0017] (1) mixing the waste cemented carbide grinding material with acid solution to obtain a mixed slurry;

[0018] The waste carbide grinding material is mixed with acid solution, and the metal elements such as cobalt and nickel in the waste carbide grinding material react with the acid to be converted into soluble metal ions, and cobalt and nickel can be separated and recovered.

[0019] Furthermore, before the waste carbide grinding material is mixed with the acid solution, the waste carbide grinding material is dried and crushed; the drying process can be carried out by hot air drying or drying equipment (such as a drying furnace, a drying machine, etc.), and the waste carbide grinding material is placed in the drying equipment, and the oil therein is removed by heating and ventilation to prevent affecting the treatment effect. The crushing process can be carried out by crushing equipment (such as a crusher, a ball mill, etc.), and the particle size of the dried waste carbide grinding material is reduced, making it easier to separate and purify it in the subsequent recovery of metal elements such as cobalt, nickel, and tungsten.

[0020] Furthermore, the addition amount of the acid solution and the waste carbide grinding material is 250ml-300ml:100g.

[0021] Furthermore, the acid solution includes one or more of dilute hydrochloric acid, dilute sulfuric acid, dilute nitric acid and dilute phosphoric acid. The concentration of the acid solution is 1 mol / L-1.5 mol / L;

[0022] Furthermore, the temperature of mixing the waste cemented carbide grinding material and the acid solution is 60° C.-70° C. and the time is 6 h-8 h.

[0023] (2) performing solid-liquid separation on the mixed slurry to obtain an acid leaching solution and solid slag, wherein the acid leaching solution includes cobalt ions, nickel ions, and tungstate ions;

[0024] The mixed slurry after the reaction is a solid-liquid mixture, which is subjected to solid-liquid separation treatment such as filtration or centrifugal separation to obtain an acid leaching solution and solid slag; the solid slag is mainly tungsten enriched slag, and the acid leaching solution mainly contains enriched solutions of metal ions such as cobalt and nickel and some tungstate ions, and the concentration of tungstate ions in the acid leaching solution is: 8.5g / L-25g / L.

[0025] (3) After the pH of the acid leaching solution is adjusted to 1.0-2.5, the tungstate ions are adsorbed and separated by a weakly basic anion exchange resin, and the tungstate ions are adsorbed by the weakly basic anion exchange resin to obtain a resin loaded with tungstate ions and a cobalt-nickel solution;

[0026] In this embodiment, weakly basic anion exchange resin is added to absorb and separate tungsten in the acid leaching solution. The weakly basic anion exchange resin is a commercially available finished resin, such as resin D314.

[0027] Weakly basic anion exchange resins may include one or more of the following functional groups: sulfonic acid groups, primary amine groups (also known as primary amine groups, -NH2), secondary amine groups (secondary amine groups, -NHR), and tertiary amine groups (tertiary amine groups, -NR2). In a weakly basic anion exchange resin in a solution, the functional groups on the resin (such as sulfonic acid groups) can release anions and exchange with anions in the solution. The metal tungsten in the acid leaching solution can form a stable anion complex (such as tungstate). ), therefore, the anions have a strong affinity with the negatively charged groups on the surface of the weakly alkaline anion exchange resin and are easily adsorbed by the resin. 2+ ) and nickel (Ni 2+ ) mainly exists in the solution in the form of cations. Since the weakly basic anion exchange resin is used to adsorb anions, its affinity with cobalt and nickel cations is relatively weak. In this embodiment, a resin loaded with tungstate ions and a cobalt-nickel solution are obtained by adding a weakly basic anion exchange resin to adsorb tungsten in the acid leaching solution.

[0028] The cobalt-nickel solution can be further treated, such as precipitation, extraction, electrolysis, etc., to recover metal elements such as cobalt and nickel. The solid slag can be recycled to recover tungsten.

[0029] (4) Desorbing the resin loaded with tungstate ions with an alkaline solution to obtain a tungstate solution.

[0030] Resin loaded tungstate ion (WO4 2- ), the alkali solution can provide hydroxide ions (OH-) to replace the tungstate ions. When the resin loaded with tungstate ions is added to the alkali solution, the tungstate ions on the resin will react with the hydroxide ions in the alkali solution to form water-insoluble tungstate, thereby recovering tungsten.

[0031] Furthermore, the alkali solution includes one or more of sodium hydroxide solution, potassium hydroxide solution and ammonium hydroxide solution. The concentration of the alkali solution is 1 mol / L-1.5 mol / L.

[0032] It can be understood that in this embodiment, the waste cemented carbide grinding material is mixed with the acid solution, and the metal elements such as cobalt and nickel react with the acid to be converted into soluble metal ions, and the cobalt metal ions (Co 2+ ) and nickel metal ions (Ni 2+ ) mainly exists in the acid leaching solution in the form of cations. Since the weakly alkaline anion exchange resin mainly adsorbs anions, its affinity with cobalt and nickel cations is weak; the tungsten metal ions in the acid leaching solution exist in the form of anion complexes (such as tungstate WO4 2- ) exists in the acid leaching solution, and the anion complex has a strong affinity with the negatively charged groups on the surface of the weakly alkaline anion exchange resin and is easily adsorbed by the resin; adding weakly alkaline anion exchange resin to the acid leaching solution can further separate tungsten from the acid leaching solution without causing cobalt and nickel precipitation, thereby improving the recovery rate of tungsten without affecting the recovery of cobalt and nickel. Specific embodiment:

[0034] Embodiment 1:

[0035] (1) 100 g of waste carbide grinding material was mixed with 250 ml of dilute hydrochloric acid, the concentration of which was 1 mol / L, the reaction time was 6 h, and the reaction temperature was 70 °C.

[0036] (2) The mixed slurry is subjected to solid-liquid separation to obtain an acid leaching solution and solid slag, wherein the concentration of tungstate ions in the acid leaching solution is 8.5 g / L.

[0037] (3) The acid leaching solution is subjected to adsorption separation by a weakly alkaline anion exchange resin, and the tungstate ions are adsorbed by the weakly alkaline anion exchange resin to obtain a resin loaded with tungstate ions and a cobalt-nickel solution.

[0038] (4) The resin loaded with tungstate ions is desorbed with a sodium hydroxide solution to obtain a tungstate solution.

[0039] Embodiment 2:

[0040] (1) 100 g of waste cemented carbide grinding material was mixed with 270 ml of dilute hydrochloric acid, the concentration of which was 1.2 mol / L, the reaction time was 7 h, and the reaction temperature was 65 °C.

[0041] (2) The mixed slurry is subjected to solid-liquid separation to obtain an acid leaching solution and solid slag, wherein the concentration of tungstate ions in the acid leaching solution is 15.8 g / L.

[0042] (3) The acid leaching solution is subjected to adsorption separation by a weakly alkaline anion exchange resin, and the tungstate ions are adsorbed by the weakly alkaline anion exchange resin to obtain a resin loaded with tungstate ions and a cobalt-nickel solution.

[0043] (4) The resin loaded with tungstate ions is desorbed with a sodium hydroxide solution to obtain a tungstate solution.

[0044] Embodiment 3:

[0045] (1) 100 g of waste cemented carbide grinding material was mixed with 300 ml of dilute hydrochloric acid, the concentration of which was 1.5 mol / L, the reaction time was 8 h, and the reaction temperature was 70 °C.

[0046] (2) The mixed slurry is subjected to solid-liquid separation to obtain an acid leaching solution and solid slag, wherein the concentration of tungstate ions in the acid leaching solution is 25 g / L.

[0047] (3) The acid leaching solution is subjected to adsorption separation by a weakly alkaline anion exchange resin, and the tungstate ions are adsorbed by the weakly alkaline anion exchange resin to obtain a resin loaded with tungstate ions and a cobalt-nickel solution.

[0048] (4) The resin loaded with tungstate ions is desorbed with a sodium hydroxide solution to obtain a tungstate solution.

[0049] Table 1: Tungstate ion concentration and recovery rate of the acid leaching solution of Examples 1-3 and Comparative Examples

[0050] Tungstate ion concentration in acid leaching solution Recovery rate of tungsten in acid leaching solution Example 1 8.5g / L 99.15％ Example 2 15.8g / L 99.34％ Example 3 25.0g / L 99.85％

[0051] The concentration of tungstate ions in the tungstate solution was determined, and the recovery rate of tungsten in the acid leaching solution was obtained by calculating the ratio of the concentration of tungstate ions in the tungstate solution to the concentration of tungstate ions in the acid leaching solution. As shown in Table 1, the recovery rates of tungsten in the acid leaching solution in Examples 1-3 of the present invention can reach more than 99%.

[0052] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A method for separating and recovering tungsten and cobalt from a carbide grinding material pickling solution, characterized in that: The following steps are involved: (1) mixing the waste cemented carbide grinding material with acid solution to obtain a mixed slurry; (2) performing solid-liquid separation on the mixed slurry to obtain an acid leaching solution and solid slag, wherein the acid leaching solution comprises cobalt ions, nickel ions and tungstate ions; (3) After the pH of the acid leaching solution is adjusted to 1.0-2.5, the tungstate ions are adsorbed and separated by a weakly basic anion exchange resin, and the tungstate ions are adsorbed by the weakly basic anion exchange resin to obtain a resin loaded with tungstate ions and a cobalt-nickel solution; (4) Desorbing the resin loaded with tungstate ions with an alkali solution to obtain the tungstate solution.

2. The method for separating and recovering tungsten and cobalt from the acid leaching liquid of cemented carbide grinding material according to claim 1, characterized in that: The weakly basic anion exchange resin includes one or more of sulfonic acid functional groups, primary amine functional groups, secondary amine functional groups, and tertiary amine functional groups.

3. The method for separating and recovering tungsten and cobalt from the acid leaching liquid of cemented carbide grinding material according to claim 1, characterized in that: The concentration of tungstate ions in the acid leaching solution is 8.5 g / L-25 g / L.

4. The method for separating and recovering tungsten and cobalt from the acid leaching liquid of cemented carbide grinding material according to claim 1, characterized in that: The alkali solution includes one or more of a sodium hydroxide solution, a potassium hydroxide solution and an ammonium hydroxide solution.

5. The method for separating and recovering tungsten and cobalt from the acid leaching liquid of cemented carbide grinding material according to claim 1, characterized in that: The added amount of the acid solution and the waste cemented carbide grinding material is 250ml-300ml:100g.

6. The method for separating and recovering tungsten and cobalt from the acid leaching liquid of cemented carbide grinding material according to claim 5, characterized in that: The concentration of the acid solution is 1 mol / L-1.5 mol / L.

7. The method for separating and recovering tungsten and cobalt from the acid leaching liquid of cemented carbide grinding material according to claim 5, characterized in that: The acid solution includes one or more of dilute hydrochloric acid, dilute sulfuric acid, dilute nitric acid and dilute phosphoric acid.

8. The method for separating and recovering tungsten and cobalt from the acid leaching liquid of cemented carbide grinding material according to claim 1, characterized in that: In the step (1), the temperature of mixing the waste cemented carbide grinding material and the acid solution is 60° C.-70° C. and the time is 6 h-8 h.

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