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

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.