Beneficiation of Li-bearing sedimentary claystone by centrifugation

Abstract

The global shift towards electrification has led to an unprecedented demand for lithium (Li) – a key element in Li-ion battery technology. Sedimentary claystones found in Nevada have recently emerged as a new resource for Li. However, these claystones pose challenges to process due to their intricate and complex mineral composition. One of the significant challenges is that the claystones contain significant amounts of carbonate minerals such as calcite, which results in excessive processing reagent consumption. This study investigates the application of centrifugation as a gravity separation method for removing calcite from one Nevada sedimentary claystone. By varying the centrifugation time and rotation speed (RPM), a maximum of 81 % Li recovery with 82 % calcium (Ca) rejection can be obtained in the clay fraction. The study also showed that the beneficiation can reduce acid consumption during the leaching process by approximately 14 %. This study not only validates centrifugation as an effective technique to upgrade the Li sedimentary claystones, but also encourages further research of advanced gravity separation technologies for the pre-treatment of Li-bearing sedimentary claystones.