Abstract
The clean energy transition has increased the global demand of nickel sulfate used in the Li-ion batteries. A short-term solution is to refne the nickel sulfate product from nickel intermediates. In the long-term, new direct nickel sulfate productiontechnologies are needed. This research focused on the modeling-based concept development of a novel direct hydrometallurgical nickel sulfate process consisting of chemical leaching, impurity removal by precipitation, solvent extraction, andcrystallization as an alternative to the conventional nickel sulfate production route via a nickel matte intermediate. The conventional process route with the studied nickel concentrate had lower chemical consumption and waste production comparedto direct hydrometallurgical process where approximately 60% of iron was leached consuming oxygen, and the following ironprecipitation step consuming calcium carbonate resulted in a high amount of iron precipitate together with gypsum. However,hydrometallurgical alternatives are often suitable for lower ore grades or volumes and can recover copper as by-productmetal. The biggest impacts on carbon footprint from chemical consumption in the direct hydrometallurgical process weregenerated in iron precipitation and oxygen use in leaching. With the studied nickel concentrate, pyrrhotite played a key rolein both oxygen use and iron precipitation. In the leaching step, 68% of total oxygen consumption was related to pyrrhotiteleaching, while in iron removal 73% of total iron originated from pyrrhotite. Thus, especially pyrrhotite removal prior toleaching needs to be developed to reduce the carbon dioxide footprint, when the pyrrhotite content in the material is high.
Original language | English |
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Pages (from-to) | 1369-1379 |
Number of pages | 11 |
Journal | Journal of Sustainable Metallurgy |
Volume | 10 |
Issue number | 3 |
DOIs | |
Publication status | Published - Sept 2024 |
MoE publication type | A1 Journal article-refereed |
Funding
This project was funded by Business Finland, BATTRACE project (Grant no. 403/31/2020).
Keywords
- Carbon footprint
- Modeling
- Nickel sulfate
- Process design
- Simulation