In today’s era of energy transition and rapid development of the electronics industry, cobalt as a critical strategic metal, has become increasingly important. Cobalt sulfate, one of the key salt compound of cobalt, serves not only as a raw material for producing high-performance catalysts and vibrant pigments, but also as an indispensable precursor for lithium-ion battery cathode materials such as nickel–cobalt–manganese (NCM) and lithium cobalt oxide (LCO). The performance of these battery materials directly determines the endurance, safety, and lifespan of energy devices, thereby imposing extremely stringent requirements on the purity and consistency of cobalt sulfate.

However, the purification of cobalt sulfate is a complex and delicate chemical engineering process. The raw materials often contain various metallic impurities such as nickel, manganese, iron, calcium, magnesium, and copper. Traditional extraction and purification methods(such as mixer-settler systems)typically suffer from drawbacks including large equipment footprint, long residence time, low production efficiency, high energy consumption, and significant organic phase volatilization losses that lead to environmental pollution. As a result, these conventional techniques can no longer meet the modern industry’s urgent demand for high efficiency, high quality, and environmentally friendly production.
The centrifugal extractor stands out with its revolutionary technological advantages, making it the equipment of choice for the extraction and purification of cobalt sulfate.

Process Flow of CWL-M Centrifugal Extractor in Cobalt Sulfate Purification

Tiei Extraction CWL-M centrifugal extractor enables continuous, efficient, and automated counter-current extraction. The process flow is as follows:

1.Feed Pretreatment:
The crude cobalt sulfate solution containing impurities is subjected to filtration, acid adjustment, and other pretreatment steps to meet the feed requirements of the extraction process.
2.Extraction:
The pretreated cobalt sulfate solution and a specifically formulated extractant (organic phase) are continuously and precisely pumped into the CWL-M centrifugal extractor. Under a strong centrifugal field, the two phases are rapidly mixed and sheared, creating a large mass-transfer interfacial area. Cobalt ions are efficiently extracted into the organic phase, while most impurity ions remain in the aqueous phase (raffinate) and are separated and discharged.
3.Scrubbing:
The cobalt-loaded organic phase then enters the scrubbing stage. Here, it contacts a purified washing solution, which removes any entrained or co-extracted impurity ions, thereby further improving the purity of the cobalt product.
4.Stripping:
The purified cobalt-loaded organic phase proceeds to the stripping stage, where it meets the stripping agent—typically dilute sulfuric acid. Under centrifugal force, cobalt ions are efficiently “stripped” from the organic phase and transferred into the stripping solution, producing a high-purity cobalt sulfate solution. The regenerated organic phase is then recycled back to the extraction stage, significantly reducing production costs and wastewater discharge.
5.Post-Treatment:
The obtained high-purity cobalt sulfate stripping solution undergoes subsequent evaporation, concentration, crystallization, and drying processes to yield battery-grade or even higher-purity cobalt sulfate crystals.

The entire process is carried out within a continuous counter-current extraction system composed of multiple CWL-M centrifugal extractors, achieving closed-loop circulation and automated control.

Core Advantages That Make the CWL-M Centrifugal Extractor the Preferred Choice

Compared with traditional equipment, the CWL-M centrifugal extractor offers comprehensive advantages that perfectly meet the demanding requirements of high-end cobalt sulfate applications:

1.Exceptional Efficiency with Short Residence Time
In the centrifugal extractor, two phase mixing and separation are completed within seconds, resulting in an extremely short overall material residence time. This not only greatly enhances production efficiency but also minimizes co-extraction and side reactions between cobalt ions and impurities in strong acid environments, contributing to higher product purity.
2.Rapid and Thorough Phase Separation:
Driven by the powerful centrifugal force generated through high-speed rotation, the CWL-M centrifugal extractor completely overcomes the separation challenges caused by small density differences or phase emulsification. The separation is sharp and complete, with virtually no intermediate layer, ensuring stable operation throughout each extraction stage and achieving an exceptionally high phase recovery rate (>99.9%), effectively minimizing the loss of valuable materials through entrainment.
3.Compact Footprint and High Degree of Automation
A single centrifugal extractor can replace an entire large-scale mixer-settler system. With its compact design, it reduces floor space requirements by more than 70%. Meanwhile, it enables fully enclosed, continuous, and automated operation, significantly lowering manual labor intensity and human error while ensuring stable and consistent product quality.
4.Green, Energy-Efficient, and Environmentally Friendly
The fully enclosed operating system virtually eliminates organic solvent volatilization, improving workplace safety and reducing raw material consumption. Its high mass-transfer efficiency also means lower extractant usage and reduced energy consumption, aligning with modern industry’s pursuit of green, low-carbon production.

In the field of cobalt sulfate extraction and purification, the CWL-M centrifugal extractor, with its outstanding advantages in efficiency, energy saving, environmental protection, and automation, perfectly addresses the shortcomings of traditional extraction technologies. It not only serves as a key technological guarantee for improving product purity and consistency, but also acts as a powerful driving force for the cobalt refining industry’s transformation toward greater precision and environmental sustainability. Choosing the CWL-M centrifugal extractor means choosing efficiency, quality, and a sustainable future.
Email: sales@tieiextraction.com
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