Indonesia is a country that has enormous iron ore and iron sand mine that can be utilized for various industrial purposes. This research has been successfully conducted synthesis and characterization of hematite iron ore and magnetite from iron sand. Iron sand and iron ore that has been crushed manually repaired with a magnet was carried out with the HCl, and NH4OH then dried in the temperature of 150 oC and calcinated at a temperature of 500 oC. Characterization was carried out using X-ray diffraction (XRD) and X-ray fluorescence (XRF), where the preliminary information obtained from XRF results in an iron ore sample by manual separation have 95.99% of Fe2O3 and followed by compounds SiO2 (2.10%). While the iron sand contains 81.42% of Fe3O4 and 2.5% of SiO2. After the precipitation process, Fe2O3 compounds contained in iron ore has a content of 96.58% and Fe3O4 compounds contained in iron sand (86.73%).  The results of XRD indicate the dominant primary phase in iron ore is hematite or Fe2O3, and in iron, sand is magnetite Fe3O4, Before the extraction process, Fe2O3 was 58.009 μm in size and after the process of extracting the particles was reduced to 20.950 μm. While the Fe3O4, prior to the extract, has a grain size of 59.009 μm, and after an extraction process, the grain size reduced into 25.950 μm. The calculation results indicate there is a slight size difference between the grain size of iron sand and iron ore.

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Lithium is an alkaline, metallic element found primarily in the earth’s crust and seawater. Recently, the industry’s need, especially lithium batteries, has been increasing. Lithium exploration is directed to various geological environments that have the potential to contain lithium. Based on previous research, mud products from mud volcanoes can contain lithium. We conducted this research to determine the potential for lithium enrichment found in mud produced by mud volcanoes in Lapindo, Mount Anyar, and Buncitan. Samples were prepared to analyze petrography, X-ray diffraction (XRD), ICP-MS, and ICP-AES. Mineralogically, the mud sample comprises smectite, kaolinite, quartz, plagioclase, clinopyroxene, calcite, pyrite, and dolomite. Lithium in the mud sample has an average concentration of 92.5 ppm with the highest concentration of 130 ppm from the Lapindo Mud volcano. The lowest concentration of 70 ppm comes from the Buncitan Mud Volcano sample. Based on its mineralogy and structure, the dominant of smectite and kaolinite clay minerals can bind the lithium. Lithium in the study area is thought to come from altered rocks below the surface, which migrate and are bound to clay minerals predominantly found in subsurface mud.

Hydrogen is a renewable energy source that can be used as a fuel and as an  alternative to fossil fuels. Solid  storage media in solid form are safer to use than liquid (-253 oC) or gaseous media (700 bar) media. To store hydrogen in a solid medium, it requires a metal able to  interact with hydrogen . Magnesium is one of the metals which  can form metal hybrids based on MgH2 which is capable of  absorbing hydrogen up to  (7.6wt%). However, the reaction kinetics for  magnesium are  very slow, it takes at least 60 minutes to absorb hydrogen and the operating temperature is always  very high (300 oC). Several attempts have been made to add the catalytic converter  and milling time. Hydrogen storage material based on MgH2 with a 10wt%Ni catalyst was  successfully synthesized using a mechanical alloy technique with time variations of 2 hours, 5 hours, and 10 hours. From the results of the X-ray diffraction schema  at a diffraction angle of 2θ=37.87o, it shows the presence of a MgH2 phase, Ni phase is at a diffraction angle of 61.85o, the diffraction peak also shows that there was a  widening of the diffraction peak with increasing milling time, this explains that there was  a reduction in the size of the crystal. When  calculating  with the Schereer method, the crystal size of the material reaches 10 nm. The results of the DSC test indicated  a decrease in temperature of 383 oC in 41 minutes with a milling time of 10 hours.

<p>Hydrogen is an alternative energy that has a very abundant amount in nature, three-fourths of all elements in nature are hydrogen. Abundance can be developed because it can be converted into electrical energy and is expected to be able to replace fossil materials that are increasingly depleting in the future. For the management of hydrogen, a very safe storage is needed. One of the efforts by inserting hydrogen in certain metals. Magnesium is one material that is able to absorb hydrogen. But it has a disadvantage, namely the absorption and release time is very slow, this is due to the strong bond between hydrogen and magnesium. Several attempts have been intensively studied to improve the properties of Magnesium including the use of materials in the form of nanocrystals with Mechanical alloying techniques and efforts to add certain catalysts are now being actively studied. Research on the addition of Hematite (Fe2O3) catalysts to hydrogen storage materials has been carried out through Mechanical alloying techniques based on MgH2-Fe2O3. Hematite purely derived from nature has been successfully extracted chemically (precipitation method). The milled MgH2-Fe2O3 alloy samples were then analyzed by XRD and showed that the MgH2-Fe2O3 material was successfully reduced to the nanocrystal scale. The addition of catalysts and extended milling time also showed a decrease in desorption temperature.</p>