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Studi Ekstraksi Bijih Thorit dengan Metode Digesti Asam dan Pemisahan Thorium dari Logam Tanah Jarang dengan Metode Oksidasi-Presipitasi Selektif Said, Moch Iqbal Nur; Anggraini, Mutia; Mubarok, Mohammad Zaki; Widana, Kurnia Setiawan
EKSPLORIUM Vol. 38 No. 2 (2017): NOVEMBER 2017
Publisher : BRIN Publishing

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17146/eksplorium.2017.38.2.3930

Abstract

Thorium (Th) is a radioactive metal that can be formed along with uranumand rare earth metals (REM). Minerals contain radioactive elements are monazite ((Ce,La,Y,U/Th)PO4), thorianite ((Th,U)O2), and thorite (ThSiO4). Mamuju Area is containing radioactive minerals, thorite is one of them. To separate REM from radioactive elements can be conducted by exctracting thorium from thorite ore by acid digestion method using sulphuric acid (H2SO4), followed by leaching and thorium recovery in the form of thorium hydroxide by chemical precipitation using ammonium hydroxide (NH4OH). The experimental results showed that the optimum conditions of acid digestion that give the highest Th extraction percentage on solid to liquid ratio are obtained at 1:2 (g/mL) in 60 minutes with extraction percentages of Th, iron (Fe) and REM are 82.47%, 80.08%, and 83.31% respectively. The highest thorium precipitation percentage, as much as 95.47% , was obtained at pH 4.5 on room temperature (26 ± 1°C). At higher temperature (70°C), a lower percentage of thorium precipitation is obtained, as much as 83.69%. Pre-oxidation by using H2O2 solution with two times stoichiometry for 1.5 hours at room temperature is increasing Fe precipitation percentage from 93.08% to 99.93%.
Penentuan Kondisi Optimum Proses Ekstraksi Uranium dan Torium dari Terak II Timah dengan Metode Pelindian Asam Sulfat dan Solvent Extraction Trioctylamine (TOA) Anggraini, Mutia; Nawawi, Fuad Wafa; Widana, Kurnia Setiawan
EKSPLORIUM Vol. 40 No. 1 (2019): MEI 2019
Publisher : BRIN Publishing

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17146/eksplorium.2019.40.1.5378

Abstract

Tin slag II is a by-product of the second stage of tin smelting. The tin slag II contains high economic value elements in the form of radioactive elements (uranium and thorium) and rare earth elements. These elements can be utilized if they are separated from each other. The process of separating radioactive elements and rare earth elements has been carried out by leaching sulfuric acid method. The results of this process are residue containing rare earth elements and filtrates containing radioactive elements in the form of uranium and thorium sulfate. Research related to the separation of uranium and thorium sulfate in tin slag processing is only slightly published. This paper aims to determine the effectiveness of the uranium and thorium separating process by the solvent extraction method using trioctylamine (TOA). The solvent extraction process is carried out by varying the concentration of TOA used, comparison of the aqueous and organic phase (A/O) and variations in extraction time. In this study, the optimum conditions for the process were obtained at 4% of TOA concentration, 1 : 1 of A/O ratio, and mixing time of aqueous and organic phase for 2 minutes. In this condition, uranium and thorium which extracted were 67% and 0.84% respectively.
Pengendapan Unsur Tanah Jarang Hasil Digesti Monasit Bangka Menggunakan Asam Sulfat Anggraini, Mutia; Sumarni, Sumarni; Sumiarti, Sumiarti; Rusyidi, Rusyidi; Waluyo, Sugeng
EKSPLORIUM Vol. 33 No. 2 (2012): NOVEMBER 2012
Publisher : BRIN Publishing

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17146/eksplorium.2012.33.2.2662

Abstract

Rare earth elements are elements that widely used in many products. Rare earth elements nature are not found in a free state, but they are in the complex compounds, so that chemically processing is required to separate the Rare earth elements from their complex compounds. Monazite as by product of Bangka tin process contains several major elements, such as 0.298% uranium (U), 4.171% thorium (Th), 23.712% phosphat (P2O5) and 58.97% rare earth elements (REE) oxide. These elements can be individually separated through a process of precipitation stages. The separation process used in the study is the method of acid by using sulfat acid as reagen and filtrat digestion as feeds. The process of digestion dissolve the elements U, Th, RE and phosphate from the complex compound. Rare earth elements that are disolved can be separated from the complex compounds by using sulfat acid precipitation process. The objective of research is to set the optimal conditions for the Rare earth elements precipitation with sulfat acid. The result showed that the amount of sulphuric H2SO4 which added is 3.5 times volume of feed and precipitation time is 20 minutes, percentage of precipitation recovery is 61.21 % REE, 78.46 % U, and 93.56 % PO4.
Pemisahan Cerium dari Logam Tanah Jarang Hidroksida Melalui Kalsinasi dan Pelindian Menggunakan HNO3 Encer Trinopiawan, Kurnia; Purwani, Maria Veronica; Anggraini, Mutia; Prassanti, Riesna
EKSPLORIUM Vol. 40 No. 1 (2019): MEI 2019
Publisher : BRIN Publishing

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17146/eksplorium.2019.40.1.5411

Abstract

Application of Rare Earth Elements (REE) uses broadly in various fields related to modernization. It causes many companies are developing processing techniques to extract REE from rare earth mineral deposits. REE hydroxide processing into cerium oxide, lanthanum oxide, and neodymium concentrates has conducted by PSTA-BATAN in collaboration with PTBGN-BATAN. The previous economic study issued in excessive ammonia caused by the use of concentrated nitric acid in the cerium dissolution process. Therefore, process innovation is necessary to do by calcination and leaching methods using dilute HNO3. This research aims to determine the effectiveness of the calcination and leaching process with dilute HNO3. Calcination conducted at 1000°C temperatures with the observing parameters is calcination time, HNO3 concentration, and leaching rate. The result of the study is that calcination can convert REE hydroxide into REE oxide. The longer calcination time, the easier the REE oxide formed. The three hours calcination process enhances the concentration of La, Ce, and Nd from 7.80%, 28.00%, and 15.11% to 12.69%, 45.50%, and 24.45% respectively. The kinetic reaction of the RE(OH)3 calcination reaction follows a chemical reaction process with the equation y = 0.3145x + 0.0789 and R2 = 0.9497. Then, REE oxide from calcination reacted with dilute HNO3. The higher the concentration of HNO3 at various leaching levels, the better the leaching efficiency of La and Nd while Ce is impossible to leach or the leaching efficiency is close to zero. The optimum leaching process on three levels of leaching conditions is using 1 M HNO3. The leach reaction kinetics follows the core shrinkage model of the surface chemical reaction with the equation y = 0.1732x - 0.2088 and R2 = 0.9828.
Pengendapan Uranium dan Thorium Hasil Pelarutan Slag II Anggraini, Mutia; Sarono, Budi; Waluyo, Sugeng; Rusydi, Rusydi; Sujono, Sujono
EKSPLORIUM Vol. 36 No. 2 (2015): NOVEMBER 2015
Publisher : BRIN Publishing

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17146/eksplorium.2015.36.2.2776

Abstract

Tin smelting process produces waste in the form of large amount of slag II. Slag II still consist of major elements such as 0.0619% uranium, 0.530% thorium, 0.179% P2O5 and 6.194% RE total oxide. Based on that fact, the processing of slag II is interesting to be researched, particularly in separating uranium and thorium which contained in slag II. Uranium and thorium dissolved using acid reagent (H2SO4). Percentage recovery of uranium, thorium, phosphate and RE oxides by dissolution method are 98.52%, 83.16%, 97.22%, and 69.62% respectively. Dissolved uranium, thorium, phosphat, and RE were each precipitated. The factors which considerable affect the precipitation process are reagent, pH, temperature, and time. NH4OH is used as precipitation reagent, optimum condition are pH 4. Temperature and time reaction did not influence this reaction. Percentage recovery of this precipitation process at optimum condition are 93.84% uranium and 84.33% thorium.
Peningkatan Perolehan Uranium, Torium, dan Logam Tanah Jarang dalam Residu Pelarutan Parsial pada Pengolahan Monasit Fatihah, Novita Sari; Anggraini, Mutia; Pratama, Afiq Azfar; Widana, Kurnia Setiawan
EKSPLORIUM Vol. 42 No. 2 (2021): NOVEMBER 2021
Publisher : BRIN Publishing

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17146/eksplorium.2021.42.2.6044

Abstract

Monazite is a by-product of tin processing containing phosphate, rare earth elements, and radioactive elements such as uranium and thorium. These elements can be utilized optimally if separated from one another through processing. Monazite processing includes decomposition, partial dissolution, and precipitation processes. The separation of rare earth elements from radioactive elements in monazite is carried out through a partial dissolution process, but the separation is not optimal so that further processes are needed to increase the recovery of these elements. In this study, the process was carried out using two methods, namely total dissolution with hydrochloric acid (HCl) which aims to dissolve all elements in the precipitate and precipitation with ammonium hydroxide (NH4OH) which aims to separate radioactive elements and rare earth elements. Both methods were carried out under optimum process conditions with various variations in pH, temperature, and time. Based on observations, it was found that the optimum solubility of each element was 67.6% uranium, 15.3% thorium and 50.8% LTJ under the dissolving process conditions of pH 1, at 80°C for 2 hours. While in the deposition process, the precipitation recovery of each element is 57% uranium, 75.7% thorium, 4.8% rare earth metals at pH 6 conditions. Based on these data, it can be concluded that uranium, thorium, and rare earth elements can be dissolved at pH 1, at 80°C for 2 hours, and can be separated at pH 6 precipitation conditions.
Validation of The Gravimetry Method for Determining Rare Earth Elements Oxides Pratama, Afiq Azfar; Hidayat, Amalia Ekaputri; Rommy; Indryati, Suci; Laksmana, Roza Indra; Trinopiawan, Kurnia; Purwanti, Tri; Widana, Kurnia Setiawan; Putra, Aditya Widian; Anggraini, Mutia; Nasrullah, Dzaki Hasan
EKSPLORIUM Vol. 45 No. 1 (2024): MAY 2024
Publisher : BRIN Publishing

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.55981/eksplorium.2024.6972

Abstract

The demand for minerals to meet technological developments is increasing, including minerals that contain rare earth elements (REE). The levels of REE in solids can be determined using conventional analysis methods (gravimetry) and instruments. Even though the instrument method provides more accurate results with a small amount of analyte, the cost is higher compared to the gravimetric method, which requires more analyte and provides good results. Therefore, the gravimetric method is a solution for areas with limited instruments and budgets. The study aims to validate the gravimetric method for determining REE oxides levels, evaluate its precision and accuracy, and assess its feasibility of use. In this study, two methods were used for REE analysis: the ASTM E2941-14 method with sample weight modification and the addition of acid to increase REE oxides recovery and a precipitation method using oxalic acid. The validation stages include sample dissolution, precipitation, filtration, and ash-making. The research results show that the RSD value is 0.3154, which is smaller than 2/3 of Horwitz's CV, namely 4.1727, which means it meets the precision acceptance requirements of ISO/IEC 17025:2017. The REE oxides recovery value, which indicates accuracy, also increased to 97.74%. Therefore, the gravimetric method can be used as an alternative for determining REE oxides levels.
Analytical Method Validation of Thorium in Ore Sample Using UV-Vis Spectrophotometer Indryati, Suci; Hidayat, Amalia Ekaputri; Pratama, Afiq Azfar; Laksamana, Roza Indra; Widana, Kurnia Setiawan; Ramlan, Muhammad Alif; Purwanti, Tri; Prassanti, Riesna; Anggraini, Mutia; Rommy, Rommy
EKSPLORIUM Vol. 44 No. 2 (2023): NOVEMBER 2023
Publisher : BRIN Publishing

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.55981/eksplorium.2023.6965

Abstract

Monazite contains several rare earth elements (REE) along with radioactive elements, i.e., thorium (Th) and uranium (U). Thorium content in monazite is several times higher than uranium. Monazite contains around 12% thorium oxide, but the thorium content in this mineral varies depending on location. To determine the thorium content in monazite, an appropriate and validated analytical method is needed so that the reliability of the test results can be trusted. Apart from that, method validation is one of the clauses in SNI ISO/IEC 17025:2017 that must be fulfilled by the laboratory to be certified and produce reliable data. This research aims to validate analytical methods for non-standard and modified methods that are likely to be used outside the scope. In this research, the method used to digest and analyze thorium in mineral samples refers to the ASTM E2941-14 method with several modifications. Therefore, the analysis method needs to be validated. Validation of the analytical method is carried out by testing several parameters such as linearity and working range tests, accuracy, precision (repeatability), Limit of Detection (LOD), and Limit of Quantitation (LOQ). The results of linearity, accuracy, and repeatability tests that meet the acceptance requirements can be used as a method of validation evaluation. The results of the method validation parameter test met the acceptance requirements, with the linearity test showing a coefficient of determination (R2) of 0.997, the accuracy test showing % a recovery value of 106.22%, and the precision (repeatability) test showing %RSD of 3.76% with LOD value is 0.650 mg/L, and LOQ is 0.724 mg/L. Based on the results of these parameter tests, the method for analyzing thorium in mineral samples was validated.