Catalog Home Page

Acid roasting of spodumene: Microwave vs. conventional heating

Salakjani, N.Kh., Singh, P. and Nikoloski, A.N. (2019) Acid roasting of spodumene: Microwave vs. conventional heating. Minerals Engineering, 138 . pp. 161-167.

Link to Published Version: https://doi.org/10.1016/j.mineng.2019.05.003
*Subscription may be required

Abstract

The use of microwave ovens in the acid roasting of spodumene as part of the process for lithium extraction was investigated and compared with conventional furnace heating. The effects of various key process factors were evaluated. Conventional acid roasting of 5 g of β-spodumene at 250 °C for 60 min was highly effective in extracting lithium in the presence of 80% excess concentrated sulphuric acid. The microwave process achieved nearly complete recovery of lithium with 20 s of irradiation. The potential to reduce the amount of excess acid required by grinding the sample to achieve a slight reduction in particle size was studied, and almost complete recovery was observed with only 15% excess acid. Microwave irradiation of the sample for longer than 20 s resulted in a reduction in lithium extraction, with the lowest value being 42% after 240 s of microwave irradiation. The mechanism of heating and the reverse reaction of Li + and H + were explored as possible explanations of this effect. The energy consumption of the conventional muffle furnace heating method in this study was calculated to be 10.4 MJ which was significantly greater than the microwave energy of 15.4 kJ required to achieve the same percentage of Li extraction from β-spodumene.

Item Type: Journal Article
Murdoch Affiliation: Engineering and Energy
Publisher: Elsevier BV
Copyright: © 2019
URI: http://researchrepository.murdoch.edu.au/id/eprint/45716
Item Control Page Item Control Page