Nickel Sulfate |CAS 10101-97-0
Nickel sulfate, with CAS number 10101-97-0, generally refers to the green crystalline compound hexahydrate. It is mainly used in industries such as power batteries, electroplating, catalysis, and printing and dyeing. In the electroless nickel plating industry, it is often used as a component of the plating solution along with sodium hypophosphite, malic acid, and lactic acid. Its market price generally follows the price trend of metallic nickel.
I. Basic Information
English Name: Nickel Sulphate
Molecular Formula: NiSO4.6H2O
CAS Number: 10101-97-0
HS Code: 2833240000
EINECS Number: 231-111-4
Molecular Weight: 262.84
Solubility: 65.0 g/100mL (20℃)
Melting Point: 53℃
Physicochemical Properties: It is a green monoclinic crystal. It loses its six waters of crystallization when heated to 103℃. Soluble in water, the aqueous solution is acidic; readily soluble in alcohol and ammonia.
II. Production Processes
There are several methods for producing nickel sulfate, and the quality, grade, and impurity content of the finished product vary significantly depending on the process.
1. Metallic Nickel Dissolution Method: Reacting metallic nickel with sulfuric acid yields NiSO4. The reaction equation is: Ni + H2SO4 = NiSO4 + H2.
2. Nickel Ore Processing Method: Nickel ore is first processed into intermediate products such as high-grade nickel matte, nickel hydroxide, nickel oxide, or nickel carbonate. These intermediate products are then dissolved in sulfuric acid, concentrated, and crystallized to obtain NiSO4·6H2O.
3. Hydrometallurgical Intermediate Product Production Method: Nickel ore is processed using a hydrometallurgical process to obtain nickel-containing intermediate products, such as nickel-cobalt-manganese hydroxide. These intermediate products are then dissolved in sulfuric acid, followed by impurity removal, concentration, and crystallization to finally obtain NiSO4.
4. Nickel-containing waste preparation method: This method utilizes nickel-containing waste, such as used batteries and electroplating residue, through a series of processing steps to recover nickel and produce nickel sulfate. Some domestic companies, such as GEM Co., Ltd., Chizhou Xien Co., Ltd., and Bangpu Recycling Co., Ltd., use this method.
5. Copper electrolysis waste liquid recovery method: During copper electrolytic refining, nickel accumulates and enriches in the electrolyte in ionic form. Typically, the electrolytic waste liquid is first treated to remove copper, and then the copper-removed solution is used for nickel removal. Nickel removal methods such as crystallization, extraction, and ion exchange can be used to recover NiSO4. Common crystallization methods include direct-fire concentration, electrothermal concentration, freeze crystallization, vacuum evaporation concentration crystallization, and vacuum evaporation freeze crystallization.
6. High-pressure acid leaching (HPAL) process: Primarily used for processing laterite nickel ore. Under high temperature, high pressure, and acidic conditions, selective leaching of nickel and cobalt is achieved, with nickel and cobalt recovery rates exceeding 90%. This process is suitable for low-grade nickel ores with high iron and cobalt content and low silicon and magnesium content. When enriching nickel and cobalt from the leaching solution, sulfide precipitation (Msp) or hydroxide precipitation (MHP) techniques can be used.
7. High-grade nickel matte preparation method: High-grade nickel matte is floated to obtain nickel sulfide concentrate and a mixture of nickel oxide and nickel alloys; the nickel sulfide concentrate is mixed with pyrolusite and sulfuric acid and subjected to aerobic leaching to obtain the first leaching solution; the mixture of nickel oxide and nickel alloys is mixed with sulfuric acid and subjected to atmospheric pressure leaching to obtain the second leaching solution; the first and second leaching solutions are mixed with an oxidant for oxidation treatment, then the pH is adjusted to remove iron, and solid-liquid separation is performed to obtain the filtrate; the filtrate is extracted and deoiled to obtain nickel sulfate.
III. Specifications
Content(asNi)≥22.0%
Cl≤0.1%
NH4≤0.03%
Al≤0.003%
Ca≤0.02%
Fe≤0.002%
Co≤0.2%
Cu≤0.002%
Zn≤0.003%
Pb≤0.001%
Water-insolublematter≤0.03%
IV. Applications of Nickel Sulfate in the Battery Industry
1. Used as a precursor material for ternary lithium batteries
NiSO4 is prepared by mixing nickel sulfate, cobalt sulfate, and manganese sulfate in a certain proportion using processes such as co-precipitation. For example, in the preparation of the nickel-cobalt-manganese ternary precursor NCM523 (nickel, cobalt, and manganese ratio of 5:2:3), NiSO4 is a key raw material providing nickel. High-nickel ternary precursors such as NCM811 and NCA (nickel-cobalt-aluminum) are increasingly used due to rising demands for battery energy density, leading to a growing need for NiSO4. Ternary lithium batteries offer advantages such as high energy density, long cycle life, and relatively low cost, making them widely used in new energy vehicles, 3C electronic products (such as mobile phones, laptops, and tablets), and power tools. For example, the power batteries in new energy vehicles like the Tesla Model 3 and BYD Han extensively utilize ternary lithium batteries.
2. Cathode Materials for Nickel-Metal Hydride Batteries Using nickel sulfate as the main raw material, and mixing it with other additives, a series of processes such as ball milling and sintering are used to produce cathode materials for nickel-metal hydride batteries. For example, in the production of some nickel-metal hydride batteries, NiSO4 is mixed with potassium hydroxide and lithium hydroxide, and reacted under specific temperature and pressure conditions to generate cathode materials with specific structures and properties. Nickel-metal hydride (NiMH) batteries possess high specific energy and specific power, long cycle life, good safety, and are environmentally friendly, thus finding widespread application in hybrid electric vehicles, power tools, and smart homes.
3. Cathode Materials for Nickel-Cadmium (NiCd) Batteries
NiCd battery cathode materials are prepared by mixing nickel sulfate with other metals such as cadmium and processing them through specific techniques. For example, in traditional NiCd battery production, NiSO4 and cadmium oxide are typically mixed in a certain proportion and then sintered to form the cathode material. NiCd batteries exhibit good charge-discharge performance and resistance to overcharge and over-discharge, still playing a role in certain applications such as emergency lighting and wireless communication equipment. However, due to the toxicity of cadmium and its potential harm to the environment and human health, the application scope of NiCd batteries is gradually being limited, and they are being gradually replaced by other types of batteries.
4. Applications in Battery Recycling
NiClub is an important intermediate product in the recovery of valuable metals such as nickel from waste batteries. In the recycling of waste nickel-metal hydride and nickel-cadmium batteries, a series of chemical and physical methods are used to extract nickel as nickel sulfate, which is then further purified and processed to achieve resource recycling.
Reuse: The recovered NiSO4 can be reused in battery production or other fields, reducing dependence on primary nickel resources and minimizing energy consumption and environmental pollution during resource extraction and processing.
Nickel sulfate is the main salt in electroless nickel plating solutions, providing nickel ions (Ni²) to the plating bath. In electroless plating, nickel ions are a key component in the formation of the coating. Sodium hypophosphite acts as a reducing agent, participating in the redox reaction. Electroless plating is an autocatalytic redox process; in the presence of a suitable reducing agent, nickel ions are reduced to metallic nickel and deposited on the workpiece surface. Factors such as the concentration of NiSO4 and pH value affect the stability of the plating solution. Excessively high NiSO4 concentrations may lead to decreased stability of the plating solution and a tendency for self-decomposition reactions; while a suitable pH range ensures the stability of the plating solution and the reaction rate. Nickel sulfate also has a significant impact on the performance of the coating. It can affect the hardness, wear resistance, and corrosion resistance of the coating. By adjusting the concentration of nickel sulfate, the composition of the plating solution, and the process parameters, a coating with the desired properties can be obtained.