US-20260125278-A1 - METHOD FOR RECOVERING NICKEL HYDROXIDE AND NICKEL SULFATE FROM NICKEL-CONTAINING MATERIALS

US20260125278A1US 20260125278 A1US20260125278 A1US 20260125278A1US-20260125278-A1

Abstract

The present invention provides a method for recovering nickel hydroxide and nickel sulfate from nickel-containing materials, wherein the nickel-containing materials are crushed and pulverized and then leached with sulfuric acid, leached residue separation and filtrate separation are performed and then the pH is adjusted to recover nickel hydroxide, and the recovered nickel hydroxide is further subjected to a sulfation reaction to recover nickel sulfate.

Inventors

Tae-Gong Ryu
Jun-Ho Shin
Jae-Min Jeong

Assignees

KOREA INSTITUTE OF GEOSCIENCE AND MINERAL RESOURCES

Dates

Publication Date: 20260507
Application Date: 20230927
Priority Date: 20221006

Claims (15)

1 . A method for recovering nickel hydroxide from nickel-containing material, comprising steps of: (a-1) crushing and pulverizing a multilayer ceramic capacitor process sludge; (a-2) leaching the crushed and pulverized multilayer ceramic capacitor process sludge with sulfuric acid to form a first sulfuric acid leachate containing a primary filtrate; (a-3) separating a leached residue and the primary filtrate from the first sulfuric acid leachate; (a-4) performing a primary pH adjustment on the first sulfuric acid leachate, from which the leached residue has been separated, to form a second sulfuric acid leachate containing a primary pH-adjusted impurity precipitate and a secondary filtrate; (a-5) separating the primary pH-adjusted impurity precipitate and the secondary filtrate from the second sulfuric acid leachate; (a-6) performing a secondary pH adjustment on the second sulfuric acid leachate, from which the impurity precipitate has been separated, to separate nickel hydroxide; and (a-7) washing the separated nickel hydroxide to recover nickel hydroxide, wherein in the step (a-2) of leaching the crushed and pulverized multilayer ceramic capacitor process sludge with sulfuric acid to form a first sulfuric acid leachate containing a primary filtrate, a leaching temperature ranges from 10 to 90° C.
2 . The method of claim 1 , wherein in the step (a-1) of crushing and pulverizing a multilayer ceramic capacitor process sludge, the nickel-containing material includes nickel-containing sludge, nickel-containing slag, nickel-containing minerals, or waste ferronickel slag, which are generated during manufacturing of electrical/electronic devices and recycling process of waste electrical/electronic devices, and wherein a metallic component of the nickel-containing material includes at least one selected from a group consisting of Ni, Al, Fe, Mg, Si, Ba, Ca, P, Cu, Zn, Zr, B, Ba, Cr, Sr, and Mn.
3 . The method of claim 1 , wherein in the step (a-1) of crushing and pulverizing a multilayer ceramic capacitor process sludge, the crushing and pulverizing process comprises: a primary crushing step using a jaw crusher or a cone crusher; and a secondary pulverizing step using a rod mill, a pin mill, a ball mill, a tube mill, a pot mill, a roller mill, a turbo mill, or a tower mill, wherein a particle size of the crushed and pulverized multilayer ceramic capacitor process sludge ranges from 0.1 μm to 5 mm.
4 . The method of claim 1 , wherein in the step (a-2) of leaching the crushed and pulverized multilayer ceramic capacitor process sludge with sulfuric acid to form a first sulfuric acid leachate containing a primary filtrate, the sulfuric acid leaching is performed under conditions where a solid-to-liquid ratio of the crushed and pulverized nickel-containing material (g) to sulfuric acid solution (L) ranges from 50 to 200, and a molar concentration of the sulfuric acid solution ranges from 0.2 to 5 M.
5 . The method of claim 1 , wherein in the step (a-3) of separating a leached residue and the primary filtrate from the first sulfuric acid leachate, separation of impurity from the first sulfuric acid leachate is performed by separating the leached residue that has not leached.
6 . The method of claim 1 , wherein in the step (a-4) of performing a primary pH adjustment on the first sulfuric acid leachate, from which the leached residue has been separated, to form a second sulfuric acid leachate containing a primary pH-adjusted impurity precipitate and a secondary filtrate, a pH of the primary pH adjustment ranges from 2 to 7.
7 . The method of claim 1 , wherein in the step (a-5) of separating the primary pH-adjusted impurity precipitate and the secondary filtrate from the second sulfuric acid leachate, the separation of the impurity precipitate from the second sulfuric acid leachate is performed by a pH titration method sequentially using metal hydroxide and metal fluoride, wherein the metal hydroxide is at least one selected from a group consisting of NaOH, KOH, Mg(OH) 2 , Ca(OH) 2 , and Al(OH) 3 , and wherein the metal fluoride is at least one selected from a group consisting of sodium fluoride (NaF), ammonium fluoride (NH 4 F), potassium fluoride (KF), ferrous fluoride (FeF 2 ), ferric fluoride (FeF 3 ), aluminum fluoride (AlF 3 ), and hydrofluoric acid (HF).
8 . The method of claim 1 , wherein in the step (a-5) of separating the primary pH-adjusted impurity precipitate and the secondary filtrate from the second sulfuric acid leachate, the separation of the impurity precipitate from the second sulfuric acid leachate is performed by a pH titration method sequentially using metal hydroxide and metal fluoride, wherein conditions for the separation of the impurity precipitate include: a pH titration temperature ranging from 10 to 90° C.; a molar ratio of nickel to metal hydroxide in the second sulfuric acid leachate ranging from 1:0.01 to 0.01:1; and a molar ratio of nickel to metal fluoride in the second sulfuric acid leachate, after nickel and impurities in the second sulfuric acid leachate have been pH-titrated and separated as metal hydroxides, ranging from 1:0.02 to 0.02:1.
9 . The method of claim 1 , wherein in the step (a-6) of performing a secondary pH adjustment on the second sulfuric acid leachate, from which the impurity precipitate has been separated, to separate nickel hydroxide, a pH of the secondary pH adjustment ranges from 6 to 13.
10 . The method of claim 1 , wherein in the step (a-7) of washing the separated nickel hydroxide to recover nickel hydroxide, the washing is performed using deionized water to remove water-soluble impurity components contained in the nickel hydroxide.
11 . A method for recovering nickel sulfate from nickel-containing material, comprising steps of: (a-1) crushing and pulverizing a multilayer ceramic capacitor process sludge; (a-2) leaching the crushed and pulverized multilayer ceramic capacitor process sludge with sulfuric acid to form a first sulfuric acid leachate containing a primary filtrate; (a-3) separating a leached residue and the primary filtrate from the first sulfuric acid leachate; (a-4) performing a primary pH adjustment on the first sulfuric acid leachate, from which the leached residue has been separated, to form a second sulfuric acid leachate containing a primary pH-adjusted impurity precipitate and a secondary filtrate; (a-5) separating the primary pH-adjusted impurity precipitate and the secondary filtrate from the second sulfuric acid leachate; (a-6) performing a secondary pH adjustment on the second sulfuric acid leachate, from which the impurity precipitate has been separated, to separate nickel hydroxide; (a-7) washing the separated nickel hydroxide to recover nickel hydroxide; and (a-8) performing a sulfation reaction between the recovered nickel hydroxide and a sulfuric acid compound to recover nickel sulfate, wherein in the step (a-2) of leaching the crushed and pulverized multilayer ceramic capacitor process sludge with sulfuric acid to form a first sulfuric acid leachate containing a primary filtrate, a leaching temperature ranges from 10 to 90° C.
12 . The method of claim 11 , wherein in the step (a-8) of performing a sulfation reaction between the recovered nickel hydroxide and a sulfuric acid compound to recover nickel sulfate, the sulfuric acid compound is at least one selected from a group consisting of: sulfuric acid (H 2 SO 4 ), sulfurous acid (H 2 SO 3 ), hyposulfurous acid (H 2 SO 2 ), magnesium sulfate (MgSO 4 ), magnesium sulfite (MgSO 3 ), magnesium hyposulfite (MgSO 2 ), calcium sulfate (CaSO 4 ), calcium sulfite (CaSO 3 ), calcium hyposulfite (CaSO 2 ), ferrous sulfate (FeSO 4 ), ferrous sulfite (FeSO 3 ), ferrous hyposulfite (FeSO 2 ), ferric sulfate (Fe 2 (SO 4 ) 3 ), ferric sulfite (Fe 2 (SO 3 ) 3 ), ferric hyposulfite (Fe 2 (SO 2 ) 3 ), ammonium sulfate ((NH 4 ) 2 SO 4 ), aluminum sulfate (Al 2 (SO 4 ) 3 ), aluminum sulfite (Al 2 (SO 3 ) 3 ), and aluminum hyposulfite (Al 2 (SO 2 ) 3 ).
13 . The method of claim 11 , wherein in the step (a-8) of performing a sulfation reaction between the recovered nickel hydroxide and a sulfuric acid compound to recover nickel sulfate, the sulfation reaction is performed under conditions characterized by: a molar ratio of nickel hydroxide to the sulfuric acid compound, expressed as a molar ratio of SO 4 /Ni, ranging from 0.5 to 5; a reaction temperature ranging from 80° C. to 800° C.; and a reaction time ranging from 0.5 hour to 36 hours.
14 . A nickel hydroxide recovered by the method for recovering nickel hydroxide from nickel-containing material according to claim 1 .
15 . A nickel sulfate recovered from the method for recovering nickel sulfate from nickel-containing material according to claim 11 .

Description

TECHNICAL FIELD The present disclosure relates to a method for recovering nickel hydroxide and nickel sulfate from nickel-containing materials, wherein the nickel-containing materials are crushed and pulverized and then leached with sulfuric acid, leached residue separation and filtrate separation are performed and then the pH is adjusted to recover nickel hydroxide, and the recovered nickel hydroxide is further subjected to a sulfation reaction to recover nickel sulfate. BACKGROUND ART Nickel is widely used across various industries, and its consumption is gradually increasing, particularly due to industrial advancements and the expansion of markets for electric vehicles (xEV), energy storage systems (ESS), and lithium-ion batteries. As a result, domestic nickel consumption is on the rise, and among the top five imported minerals in the year of 2020 (nickel, palladium, platinum, silicon, and lithium), nickel showed the highest dependence on imports. The domestic demand for nickel is met either by importing and refining foreign raw ores or by importing alloys and compounds in their entirety for industrial use. In particular, nickel hydroxide and nickel sulfate, which are in compound form, are primarily used as plating materials and cathode materials for secondary batteries. Furthermore, with the explosive growth in demand for electric vehicles and energy storage systems (ESS), the nickel market has been expanding accordingly. In particular, the demand for high-nickel lithium-ion batteries is increasing due to the need for high current density and the unstable supply of cobalt raw materials. As a result, the demand for nickel compounds is expected to exceed 40,000 tons by the year of 2025. Domestic nickel production from nickel ore is minimal, and the country is highly dependent on imports. Nickel ore is primarily imported from Southeast Asia (the Philippines, Indonesia, China, etc.), while processed nickel powder products are imported from Canada and the United Kingdom. However, due to recent resource weaponization policies, export restrictions by resource-rich countries, and trade wars, the supply and price volatility of nickel resources have intensified, necessitating a stable supply chain. Moreover, Nickel, which is mainly used in industries such as lithium-ion batteries, steel alloys, plating, semiconductors, and multilayer ceramic capacitor (MLCC), is also accompanied by the generation of nickel-containing materials during processing. However, as nickel has been designated as a hazardous chemical, there is an urgent need for proper disposal methods for nickel-based waste and the development of stable and environmentally friendly recovery technologies. Currently, technologies for recovering and refining nickel from nickel-containing materials are limited to high-cost solvent extraction, electrowinning, or reprocessing into low-grade nickel raw materials for use in alloy and steel manufacturing. In particular, domestic technological development for recovery and refining through high-efficiency, low-cost hydrometallurgical processes remains insufficient. Therefore, to address the heavy reliance on nickel imports and to secure a stable supply of raw materials, the importance of developing technologies that efficiently recover and recycle nickel from nickel-containing materials, including nickel ores, is increasingly being emphasized. Therefore, through extensive research and dedicated efforts, the applicants of the present disclosure have developed a method for recovering nickel hydroxide and nickel sulfate from nickel-containing materials. In this method, the nickel-containing materials are crushed and pulverized, followed by sulfuric acid leaching. The leached residue and filtrate are then separated, and pH adjustment is performed to recover nickel hydroxide. The recovered nickel hydroxide is further subjected to a sulfation reaction to obtain nickel sulfate, thereby completing the present disclosure. DISCLOSURE Technical Problem Accordingly, a purpose of the present disclosure is to a method for recovering nickel hydroxide by crushing and pulverizing nickel-containing materials, leaching them with sulfuric acid, separating the leached residue and filtrate, and then adjusting the pH. In addition, another purpose of the present disclosure is to provide a method for recovering nickel sulfate by further subjecting the recovered nickel hydroxide to a sulfation reaction. Furthermore, still another purpose of the present disclosure is to provide the nickel hydroxide recovered through a method for recovering nickel hydroxide wherein nickel-containing materials are crushed and pulverized, leached with sulfuric acid, the leached residue and filtrate are separated, and then the pH is adjusted. Moreover, still another purpose of the present disclosure is to provide the nickel sulfate recovered through a method for recovering nickel sulfate wherein the recovered nickel hydroxide is further subjected to a sulfation r