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"Batteries on the market today still use liquid-type electrolytes, which can result in safety issues caused by electrolyte leakage. Therefore, studies that search for solid-state electrolytes are important for resolving these issues. In this research, a composite of lithium phosphate-montmorillonite-polyvinylidene fluoride (Li3PO4-MMT-PVDF) has been characterized with the aim of detecting the electrochemical performance of Li3PO4 with the addition of MMT. Li3PO4 samples were prepared through a solid-state reaction, which was then mixed with MMT, which had a composition ranging from 5 wt% to 20 wt%, and 1 wt% PVDF as a binder. This characterization was conducted with structural, morphological, and electrochemical aspects. The structural test showed that the X-ray diffraction (XRD) pattern was dominated by Li3PO4 peaks and MMT aluminosilicates. The electrochemical characterization indicated that the conductivity value of the composites was greater than that of Li3PO4. The highest conductivity was achieved with a 15 wt% MMT addition, with a dielectric-constant value of 74.9 at a frequency of 10 kHz."

"Batteries on the markettoday still use liquid-type electrolytes, which can result in safety issuescaused by electrolyte leakage. Therefore, studies that search for solid-stateelectrolytes are important for resolving these issues. In this research, acomposite of lithium phosphate-montmorillonite-polyvinylidene fluoride (Li3PO4-MMT-PVDF)has been characterized with the aim of detecting the electrochemicalperformance of Li3PO4 with the addition of MMT. Li3PO4samples were prepared through a solid-state reaction, which was then mixed with MMT, which hada composition ranging from 5 wt% to 20 wt%, and 1 wt% PVDF as a binder. Thischaracterization was conducted with structural, morphological, andelectrochemical aspects. The structural test showed that the X-ray diffraction (XRD) pattern was dominated by Li3PO4 peaks and MMT aluminosilicates. The electrochemical characterization indicatedthat the conductivity value of the composites was greater than that of Li3PO4.The highest conductivity was achieved with a 15 wt% MMT addition, with adielectric-constant value of 74.9 at a frequency of 10 kHz."

"Li4Ti5O12 lithium titanate disintesis menggunakan metode sol-gel dan hidrotermal dengan memakai sumber ion lithium LiOH. Anoda komposit Li4Ti5O12/Sn dipreparasi menggunakan metode ball mill dengan 3 variasi Sn. XRD menunjukkan fasa spinel, TiO2, dan Sn. SEM memperlihatkan bahwa partikel Li4Ti5O12 memiliki ukuran berkisar 20-50 ?m dan ukuran partikel Sn berkisar 2-70 ?m. Nilai hambatan elektrolit terendah didapatkan pada kadar Sn terbesar. Peningkatan kadar Sn dapat meningkatkan kapasitas spesifik dari baterai pada uji CV. Reaksi alloying dan dealloying LixSn mengakomodasi peningkatan kapasitas spesifik pada C/D. Namun, volume ekspansi dari LixSn menyebabkan hilangnya kapasitas saat C rate meningkat. Kapasitas terbesar pada laju charge/discharge rendah dan tinggi didapatkan pada kadar Sn terbesar.

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Li4Ti5O12 lithium titanate were synthesized by sol gel and hydrothermal method with LiOH as lithium ion source. Li4Ti5O12 Sn composites anode were preparared by ball mill method with three of Sn variation. XRD shows spinel, TiO2, and Sn phases. SEM shows that Li4Ti5O12 particles are around 20 50 m size and Sn particles are around 2 70 m size. The lowest electrolyte resistance obtained at the highest Sn value. With the increasing Sn value, the specific capacity of battery can be increased from CV. Alloying and dealloying reaction of LixSn accomodate the increased specific capacity from C D. However, volume expansion from LixSn leads to loss of capacity when the C rate increases. The capacity at low and high charge discharge rate obtained at the highest Sn value. "

"Indonesia merupakan negara yang kaya akan sumber daya alam, salah satunya merupakan deposit uranium. Keterdapatan uranium di Indonesia masih merupakan hal yang jarang dijumpai sehingga dapat menjadi topik yang sangat menarik untuk dipelajari lebih lanjut. Penelitian ini bertujuan untuk mengetahui tipe deposit serta keterbentukan dari uranium yang terdapat di Desa Takandeang, Kecamatan Tapalang, Kabupaten Mamuju, Sulawesi Barat. Penelitian dimulai dengan pemetaan geologi permukaan dan radiometri dengan bantuan alat gamma surveyor (model RS 125) yang kemudian dilanjutkan dengan analisis petrologi dan petrografi, serta analisis geokimia. Berdasarkan hasil dari penelitian, diketahui bahwa batuan penyusun lapangan penelitian terdiri atas autobreksi leusitit, breksi epiklastik, lava phonolitik foidit, batupasir tufaan, dan batugamping terumbu. Data radiometri dan geokimia XRF menunjukan anomali uranium tertinggi terdapat pada autobreksi leusitit. Anomali yang terjadi pada daerah penelitian berupa rekonsentrasi unsur uranium pada batuan autobreksi yang disebabkan oleh aktivitas hidrotermal yang juga didukung tipe magma dan kontrol struktur pada daerah penelitian.

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Indonesia is rich in natural resources, one of which is a uranium deposit. In Indonesia, uranium‟s occurrence is still rarely found so it can be a very interesting topic for further study. This study aims to determine the type of deposit and the formation of uranium contained in Takandeang Village, Tapalang District, Mamuju Regency, West Sulawesi. The study began with surface geology and radiometry mapping with the help of a gamma surveyor (RS 125 model) which was continued with petrological and petrographic analysis, and geochemical analysis. Based on the results of the study, it is known that the constituent rock of the research field consists of leucitite autobreccias, epiclastic breccias, phonolytic lava phoidolytic, tuffaceous sandstones, and reef limestones. Radiometric data and XRF geochemistry show that the highest uranium anomaly is found in leucitite autobreccias. The anomaly that occurred in the study area was in the form of reconcentration of uranium elements in autobrection rocks caused by hydrothermal activity which was also supported by magma type and structural control in the study area."

"Perkembangan teknologi yang pesat memicu bertambahnya produksi ponsel cerdas. Diprediksi pada tahun 2017, pengguna ponsel cerdas di Indonesia mencapai 39,8 dari total penduduk atau sebesar 101,56 juta jiwa. Tentunya, peningkatan penggunaan ponsel cerdas ini diiringi dengan peningkatan jumlah limbahnya, di mana salah satu yang perlu diperhatikan adalah limbah baterai yang tergolong sebagai limbah B3. Dari analisis kandungan zat baterai ponsel cerdas, dapat terlihat bahwa terdapat sejumlah logam kobalt 5 ndash;20 sebagai komposisi logam terbesar dalam baterai ponsel cerdas yang masih dapat dimanfaatkan kembali, dilihat dari nilai ekonomi logam kobalt tergolong tinggi, yaitu sebesar Rp 825.208/kg.Proses daur ulang yang sering digunakan adalah proses hidrometalurgi leaching. Pelarut yang digunakan biasanya berupa asam kuat, seperti asam nitrat HNO3. Untuk meningkatkan kemurnian perolehan kembali logam berharga, dapat diteruskan dengan proses ekstraksi. Ekstraksi yang banyak digunakan adalah membran cair emulsi MCE. Optimisasi proses dilakukan dengan memvariasikan konsentrasi asam nitrat dan suhu operasi.Hasil menunjukkan bahwa kondisi optimum leaching diperoleh pada waktu 30 menit leaching menggunakan HNO3 3,0 M pada suhu 90°C, diperoleh efisiensi leaching kobalt sebesar 98,01. Studi kinetika reaksi juga dilakukan dan dihasilkan bahwa perolehan kembali logam kobalt dari limbah baterai lithium-ion menggunakan asam nitrat dikendalikan oleh reaksi permukaan dengan nilai energi aktivasi sebesar 44,67 kJ/mol. Kobalt kemudian diekstraksi dari larutan hasil leaching pada pH 3 menggunakan Cyanex 272 0,1 M dengan 2 w/v Span 80 sebagai ekstraktan dan surfaktan secara berurutan di dalam fasa membran dengan H2SO4 0,1 M sebagai larutan stripping, menghasilkan efisiensi sebesar 46,96.

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Relentless development of technology triggers the smartphone production. In 2017, it is predicted that the smartphone users in Indonesia reach about 39.8 of the total population or equals about 101.56 millons of people. The increasing number of smartphone use is followed by escalation of its waste, where its battery is classified as a toxic and hazardous waste. The analysis of the battery content shows that it is consist of cobalt metal about 5 ndash 20 as the major component that can be utilised, based on its relatively high economic value, which valued Rp 825,208 kg.

The recycle process that is usually used to recover cobalt metal is called hydrometallurgy, specifically leaching hydrometallurgy. To execute leaching, it is common to use strong acids as a solvent, e.g. HNO3. To elevate the purity of the recovery process of valuable metals, the process could be continued to extraction process. Most extraction process in the industry uses emulsion liquid membrane ELM. Process optimization is done by varying concentration of nitric acid and reaction temperature.

The result shows that the optimum leaching condition is earned in 30 minutes of leaching reaction using 3,0 M HNO3 at the reaction temperature of 90°C, resulting 98.01 of cobalt leaching efficiency. Reaction kinetics study is also done in this research and the result demonstrates that recovery of cobalt from spent lithium ion batteries by nitric acid leaching is controlled by surface reaction with activation energy value of 44.67 kJ mol. Cobalt is then extracted from leach liquor on pH 3 using Cyanex 272 0.1 M with 2 w v Span 80 as extractant and surfactant respectively in membrane phase with H2SO4 0.1 M as stripping acid, resulting 46.96 efficiency."

"Salah satu anoda yang dewasa ini banyak dikembangkan untuk meningkatkan kapasitas dan performa baterai ion litium adalah anoda litium titanat (Li4Ti5O12). Anoda litium titanat memiliki kelebihan dalam aspek kestabilan termal dan karakteristik zero strain. Kekurangan dari material ini, yaitu konduktivitas listrik dan kapasitas yang rendah. Pada penelitian ini akan diobservasi perubahan karakteristik dari material anoda litium titanat yang dibuat menjadi komposit dengan grafit dan doping Fe dengan variasi konsentrasi 0,1, dan 5 mol%. Sintesis dilakukan dengan metode solid state dan hasil sintesis dikarakterisasi menggunakan XRD dan SEM, kemudian difabrikasi menjadi koin sel untuk dilakukan pengujian performa dengan EIS, CV, dan CD.

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One of many anodes currently being developed to increase the capacity and performance of lithium ion batteries is lithium titanate anode (Li4Ti5O12). The lithium titanate anode has advantages in its thermal stability and zero strain characteristic. The main disadvantages of this material are the low electrical conductivity and capacity. This research will be observing the characteristic changes of the lithium titanate material made into composites with graphite (5 wt%) and iron (Fe) doping with concentrations of 0,1, and 5 mol%. The synthesis was carried out by solid state method and the synthesized material was characterized using XRD and SEM, then fabricated into cell coins for performance testing with EIS, CV, and CD."

"The influence of U3 O8 and U3 Si2 powder diffrence toward the formation of porosity, uranium homogeneity and cladding thickness of U3 O8 -Al and U3 Si2 - Al fuel plate product. Research of raw material influence of U3 O8 and U3 Si2 in the making of U3 O8 - Al and U3 Si2 - Al fuel plate has been conducted. The U3 O8 represent result of the amonium uranil carbonate calcination process, while U3 Si2 powder result by milling ingot U3 Si2 (U - 7,5 w%)...."

"Influence of oxidation temperature and time and ZrO2 concertration on density, surface area and O/U ratio of (U3O8+ZrO2) reduction product. Reduction process of uranium oxide and zicronium oxide (U3O8+ZrO2) by hydrogen gas at temperature of 850 oC for 2 hours in reduction furnace has been carried out. The material was obtained from oxidation product of (UO2 + ZrO2) pellet became (U3O8+ZrO) powder at temperature of 400oC and 500oC for0.5 - 2 hours with variation of ZrO2 concentration from 0-0.6%...."

"The influence of the urea and HMTA as additives, time and temperature reduction on UO2 kernel specification has been studied. UO2 kernel was made up by totla gelation process uranium (TGU). Uranyl nitrate,urea, HMTA, polyvinyl alcohol (PVA) and tetra hidrofurfural (THF),were used as base materials..."

"In this research was carried out geophysical investigation using geolictric resistivity measuremnts and geological mapping conducted in purpose to know form, distribution and depth of basenent in Aloban Basin include its level of uranium mineralization..."