Iron Control in Atmospheric Acid Laterite Leaching

Minerals

卷:9

Eero Kolehmainen¹  Tero Kravtsov¹  Jarno Mäkinen²  Ville Miettinen²  Lotta Rintala² 

[1] Outotec (Finland) Oy, P.O. Box 69, FI-28101 Pori, Finland;

[2] VTT Technical Research Centre of Finland Ltd., P.O. Box 1000, FI-02044 VTT Espoo, Finland;

关键词: laterite;    nickel;    leaching;    jarosite;    precipitation;   

DOI  :  10.3390/min9070404

来源: DOAJ

【 摘 要 】

Iron control in the atmospheric acid leaching (AL) of nickel laterite was evaluated in this study. The aim was to decrease acid consumption and iron dissolution by iron precipitation during nickel leaching. The combined acid leaching and iron precipitation process involves direct acid leaching of the limonite type of laterite followed by a simultaneous iron precipitation and nickel leaching step. Iron precipitation as jarosite is carried out by using nickel containing silicate laterite for neutralization. Acid is generated in the jarosite precipitation reaction, and it dissolves nickel and other metals like magnesium from the silicate laterite. Leaching tests were carried out using three laterite samples from the Agios Ioannis, Evia Island, and Kastoria mines in Greece. Relatively low acid consumption was achieved during the combined precipitation and acid leaching tests. The acid consumption was approximately 0.4 kg acid per kg laterite, whereas the acid consumption in direct acid leaching of the same laterite samples was approximately 0.6−0.8 kg acid per kg laterite. Iron dissolution was only 1.5−3% during the combined precipitation and acid leaching tests, whereas in direct acid leaching it was 15−30% with the Agios Ioannis and Evia Island samples and 80% with the Kastoria sample.

【 授权许可】

Unknown