Magnesium removal from brine water with low lithium grade using limestone, rembang, indonesia

Abstract

Experiments have been carried out to remove magnesium ions from brine water using limestone, Rembang, Indonesia. The aim of the study was to produce brine water concentrates that were rich in lithium and did not contain magnesium elements. Brine water used has the following chemical composition: 74.67 ppm Li; 877.891 ppm Na; 1549.81 ppm K; 147.23 ppm Mg; 38.49 ppm Ca and others. The initial stages were 200 g of natural lime calcined at 900 °C for 3 hours using a furnace as a precipitation agent. It is then added to 1000 ml of brine water with a variation of 0.336 g, 1 g, 10 g, 20 g, 30 g, 40 g, 50 g by stirring for 3 hours at atmospheric pressure. The results showed that the magnesium removal from brine water began to be seen in the addition of roasted limestone of 1 g with the dominant phase as Mg0.03Ca0.97CO3 in the precipitated residue. On the addition of 10 g and 20 g of roasted limestone into brine water, the percentage of magnesium removal was almost maximum of 98.8% and 99.8% with the precipitated residues as Mg(OH)2 phases. This experiment was successful to remove magnesium from brine water so that the lithium concentration of brine water increased to 104.32 ppm Li and 105.86 ppm Li with the addition of roasted limestone of 10 g and 20 g, respectively. These results indicate that the use of roasted limestone to eliminate magnesium from brine water with low lithium grade is recommended.