The effect of dilution and lithium carbonate seed on decreasing of Mg/Li ratio from bittern salt pond waste

Bittern is a waste from making salt from salt ponds which contains quite a lot of lithium. Indonesia has bittern potential due to the shift from traditional to modern aquaculture. The lithium content in the bittern is much higher than in seawater and the magnesium content in the bittern is also very high. The high concentration of magnesium ions and other ions makes bittern have a very high viscosity. In this research, a breakthrough will be made by performing the process of separating lithium and magnesium ions through the process of decreasing the viscosity of bittern with distilled water. In this experiment, the variable of distilled water addition (dilution) and the addition of lithium carbonate seed to the bittern was carried out. The addition of distilled water varied from 0-1000 mL (0, 100, 300, 500, 700, 900, and 1000 mL) whereas the addition of lithium carbonate added about 0.262 g/L bittern (bittern A), and 1.314 g/L bittern (bittern B). The best result from the experiment was that bittern B was able to reduce the Mg/Li ratio from 212 to 17.5. The best results were only able to get lithium in 22.02% filtrate. The residues of precipitation have high silica (SiO2) content of 61.1% and magnesium (MgO) content was 12.3%. The residue phase of artificial bittern B consisted of periclase (MgO), enstatite (MgO3Si), halite (NaCl), cristobalite (SiO2), quartz (SiO2), silica complex (SiO2.SiO2), and lithium chloride (LiCl).