A novel application of Linz-Donawitz Slag for potash recovery from waste mica scrap using chlorination roasting coupled water leaching process

ABSTRACT

The present article reports a novel process for the recovery of potash values from mica scrap (K₂O 8.72%) using Linz-Donawitz Slag (LDS) and NaCl. Acid leaching of ground mica powder suggests a maximum of 22% potassium extraction. The roasting coupled water leaching process, using a mixture of LDS and NaCl, could extract a maximum of 93% potash at 900°C for 30 min roasting. The roasting temperature is the key parameter during the extraction process. The possible potash recovery mechanism is discussed on the basis of XRD, EPMA, and SEM-EDS studies of various feed and processed products.

Graphical abstract

KEYWORDS:

• Potash recovery
• mica scrap
• Linz-Donawitz Slag
• roast-leach method
• sylvite

Acknowledgements

The authors are thankful to the Head, Mineral Processing Department and Director, CSIR-IMMT, Bhubaneswar for his kind permission to publish this paper. We are also thankful to Dr. Sunil Kumar Tripathy of Tata Steel Ltd., Jamshedpur for supplying the LD Slag and to Mrs. Mamtarani Behera for her overall support during the characterization and experimentations.

Supplementary material

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