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Magnesium in nature can be found in the form of minerals and seawater. Bittern is a sea-salt industry by-product that contains magnesium and potassium salts. Usually, bittern is discharged back to the sea, even though bittern can be further processed to obtain magnesium contained in it. Magnesium oxide (MgO) nanoparticles can be used in a variety of applications because of their good surface recreation properties. In this study, precipitation of Mg2 + ions from bitterns was carried out using sodium hydroxide to produce magnesium hydroxide. Then, it was calcined and went through sonochemical process to produce nano magnesium oxide. Sonication time and amplitude were used as variables. Sample with sonication time of 16 minutes and amplitude of 30% has the smallest particles with an average diameter of 195.7 nanometers.

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Lithium minerals become a sub-economic raw material for lithium production to fulfill the lithium demand. This study is about lithium extraction from mica schist using the roasting and leaching processes. The mica schist located in Kebumen, Indonesia was used to study the phenomena during the lithium extraction process. Sodium sulfate was used as a roasting agent while 0.36 M sulfuric acid was used as a leaching agent. Solid/liquid ratio (1:5, 1:10, 1:15 and 1:20 (g/mL)) and leaching time (30, 60, 90 and 120 minutes) were used as variables in this study. The roasting process was done at 700 °С for 40 minutes while the leaching process was done at 70 °С and 350 rpm. The ratio of additive and mica schist was 1.5:1 (g/g). XRD, ICP-OES, and SEM were used to observe the formed compounds, chemical composition and morphology of the materials. HighScore Plus (HSP) was used to interpret the content of each compound in mica schist, roasted mica schist, and residue. ICP analysis confirmed that the mica schist contains 45.28 ppm of lithium. It is supported by XRD that lithium exists in mica schist as lepidolite (KLi2AlSi4O10(F,OH)2). Sulfate roasting did not affect the type of lepidolite but the lepidolite reactivity against the chemical agent. SEM analysis shows that the roasting process reduced the average particle size from 32.17 to 27.16 µm. ICP analysis of roasted mica schist shows that lithium concentration was reduced from 45.28 to 1.27 ppm. The optimum result from this study was 97.66 % extraction of lithium while solid/liquid ratio was 1:5 (g/ml) and leaching time was 30 minutes. HSP shows that lepidolite contents in initial mica schist, roasted mica schist and residue were 60.6; 24.3 and 18.7 %, respectively. Lithium concentration in the residue according to ICP analysis is 1.06 ppm.

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.

This study aimed to decompose lignin from oil palm midrib (OPF) bonds using the fungus Pleurotus ostreatus with various substrates (corn and rice husk). Lignin and cellulose levels before and after mushroom culture were tested by the Chesson-Datta method. Substrate variation with corn and husk rice showed that the addition of corn did not play a role in lignin decomposition. After being given treatment, the best degradation was using 0.6 grams of rice bran and 0.4 grams of CaCO3, 22.01% for lignin and 32.74% for cellulose.