[en] Xenotime sand is one of potential natural resources, because it contains rare earth elements (REEs) among of which are Y, Dy, Gd, La, Ce, Nd that have been used a lot in various of fields both nuclear and non-nuclear. In spite of containing REEs, xenotime is also containing U and Th radioactive elements. Therefore that sand has a very strategical and economical values. This investigation aims at gaining the separation and the purification of yttrium (Y) which is relatively pure from REEs concentrate of xenotime sand processed product. The yttrium is used for developing the newer and renewable energies among of which are: yttrium aluminium garnet laser (YAG-laser), oxygen sensor solid electrolyte based Yttria-stabilized zirconia (YSZ), and solid oxide fuel cell (SOFC). The processing stages done namely xenotime sand digestion by sulfuric acid, quenching, precipitation, drying, dilution, extraction and stripping processes. The extraction processes used D2EHPA extractant which was diluted by dodecane. The stripping process used feed of extraction product (extract) with sulfuric acid. The determination of yttrium (Y) concentration, and impurities of another rare earth elements: such as dysprosium (Dy), gadolinium (Gd), lanthanum (La), cerium (Ce), neodymium (Nd), were analyzed by using X-ray fluorescence. In the yttrium (Y) extraction process, the influencing variables were: nitrate acid concentration in feed solution, D2EHPA concentration in dodecane, and extraction time. In the stripping process, the influencing variables were: sulfuric acid concentration and extraction time. From the investigated variables namely: nitrate acid molarity 1 M, extractant concentration of 30 % D2EHPA in dodecane, and extraction time of 15 minutes. In that condition yielded the extraction efficiency of Y was 98.63 %. In the stripping process, the optimum product used sulfuric acid of 4 M molarity and stripping time of 20 minutes. In this condition the stripping efficiency obtained was 59.29 %, with the impurities of Dy 198 ppm and Gd, Ce, La, Nd below 100 ppm. (author)

[en] Yttrium has been separated from rare earth concentrates by precipitation in fractional hydroxide using urea. The purpose of this research is to increase the yttrium rate resulting from the sedimentary process through separation of yttrium from other rare earth in fractional hydroxide precipitation using urea. In this research, we study the process variable of the concentration of urea, the ratio of feed volume to condensation volume of urea, as well as the temperature. Determination analysis of the rare earth rate is conducted using an X-ray spectrometer. The best result Y=92.89 % is obtained at a concentration of urea of 50 %, a level of precipitation of 3 times, and a temperature of 80°C. (author)

[en] The separation of uranium and yttrium in hydrochloric acid was extracted by D₂EHPA in dodecane. This process used liquid-liquid extraction method. The variables studied were the concentration of hydrochloric acid, the concentration of extractant, time of extraction, and the temperature of extraction. The data evaluation of the research showed that the optimum condition was as follows: the concentration of HCI = 0.2 M, the concentration of extractant = 0.15 M D₂EHPA, the time of extraction = 15 minutes, and the temperature of extraction = 20^oC. It was found that the distribution coefficient of uranium was = 34.43, the distribution coefficient of yttrium was = 2.20, and the separation factor of U-Y= 15.65

[en] A neodymium (Nd) separation extraction from Nd concentrate with addition of Al(NO₃)₃ as salting out agent was employed using mixture of TOA - TOPO extractant in kerosene diluents. Neodymium (Nd) is a rare earth metal element that has many benefits such as material for magnets and superconductors. The main source of Nd is monasite ore which is found in many islands in Indonesia. By the potential use and source of Nd raw materials it is important to do research for separation Nd from other rare earth elements. The purpose of this study was to optimize the extraction solvent system comprising mixture of TOA and TOPO extractants in kerosene diluent to separate Nd from the impurities with the addition of Al(NO₃)₃ salt. The variables studied were variation of salt concentration, HNO₃ concentration in aqueous phase feed, and ratio of TOA: TOPO mixture in kerosene diluent. From this work, to extract 0.3 g/ mL of Nd concentrate it was found that the optimum operating conditions were at concentration of Al(NO₃)₃ 0.071 g / mL, concentration of HNO₃ 0.5 M, and TOA: TOPO ratio = 0.5: 1, obtained Kd Nd 0.204; extraction efficiency 16.931 %; SF Nd - Y = 5.23 and SF Nd - Pr = 2.34. (author)

[en] Separation of yttrium (Y), dysprosium (Dy), and gadolinium (Gd) by liquid-liquid extraction have been done from the yttrium concentrate processed result of senotim sand. Senotim sand is a source of rare earth elements with the main content of yttrium. Solvents that used for the extraction processes were tri butil phosphate (TBP) and bis(2-ethylhexyl) phosphate (D2EHPA) in kerosene diluent. The extraction feed was concentrates dissolved in nitric acid. Determination of Y, Dy, and Gd were analyzed using X-ray fluorescent. The purpose of this study was to obtain the relatively pure separated of yttrium. In the separation extraction process of Y, Dy, and Gd, the influent variables were: the concentration of nitric acid in the feed solution, the extraction time, the ratio of the feed and the organic phase and concentration of the solvent in the organic phase. From the experiments was obtained the best result with conditions of acidity feed of 0.5 M, extraction time of 15 minutes, stirring speed of 250 rpm, solvent 30 % D2EHPA in kerosene diluent, ratio aqueous (FA ): inorganic phase (FO) = 1: 1. In this condition the separation factor obtained for Y-Dy and Y-Gd were 22.576 and 59.292 respectively. (author)

[en] The process to made of rare earth oxide from xenotime sand has been done. The aim of research is to determine the optimum conditions of the process of making rare earth oxide from the xenotime sand. The steps of process include digestion, precipitation, extraction and calcinations. The digestion of xenotime sand under mesh size of 200-325 was carried out by using concentrated H₂SO₄ solution of 96 %, and 30 % H₂O₂ at 210 °C for 4 hours. The obtained filtrate of digestion was used as the feed to the precipitation process. There were two materials used in precipitation, i.e. 25 % of ammonia solution, and a mixture of 30 % (w/v) of 25 % ammonia and H₂C₂O₄ solutions (aq). The analysis of the product was done by using an X-ray fluorescence spectrometer. The oxide of rare earth was prepared by precipitation, extraction and calcination. The studied variables included pH of solution of precipitation step. The operating temperature and time were studied in the calcination. The optimum condition of stepwise precipitation occurs under process of using 25 % of ammonia at pH 4. At those condition the rare earth element concentration gained as follow Y = 46.79 %, La = 4.33 %, Ce = 5.12 %, Nd = 2.25 %, Sm = 0.95 %, Gd = 0.12 %, dan Dy = 0.08 %. On the other hand, the best result of simultaneous precipitation using mixed solution ammonia 25 % and oxalic acid of 30 % b/v occurred at pH = 2.5. The concentration of oxide elements were Y = 48.03 %, La = 0.42 %, Ce = 1.32 %, Nd = 2.38 %, Sm = 0.18 %, Gd = 0.07 %, Dy = 0.07 %. The best condition of calcinations of both precipitation steps occurred at temperature of 1000 °C for 2 hours calcinations time. (author)

[en] The extraction of Zr and Hf using solvent mixture of TBP and Cyanex-921 has been done. As the water phase used a mixed solution of ZrO(NO_3)_2 and HFO(NO_3)_2 containing Zr 26 g / L and Hf 0.5 g / L and 3.5 M NaNO_3, while the extractant or the organic phase used a mixture of 30% TBP and Cyanex-921 with a variation of the concentration is diluted with kerosene. The parameters studied were extractant concentration, stirring speed, stirring time, and the ratio of aqueous phase and an organic phase. For the analysis of Zr and Hf is used the X-Ray Fluorescence (XRF). From the results of the extraction process optimization Zr and Hf from Zr-Hf solution using a mixture of TBP and Cyanex 921 extractant obtained the following conclusions: the concentration of Cyanex 921 extractant was 12.5%, while stirring time for 25 minutes with a stirring speed of 500 rpm , and the ratio of the water phase and the organic phase was 1 : 1.5. In this condition acquired a separating factor (FP) Zr-Hf = 6.447, the extraction efficiency of Zr = 93.57% and Hf = 69.31%, while KdZr = 14.556 and KdHf = 2.258, respectively. (author)

[en] Leaching of Y decomposition results of xenotime sand using Na₂CO₃ and NaHCO₃ has been carried out. This process includes roasting xenotime sand with Na₂CO₃ and NaHCO₃ and the dissolution process using HCl. To determine the success of the leaching process used yttrium (Y) as a metal representation of rare earth metals. Variables that influence the effectiveness of decomposition include weight ratio of sand with the weight of reagent, roasting temperature, HCl concentration and stirring time. From the results of the study obtained the results of Y were optimum dissolved on weight ratio of xenotime sand and 5 :1 reagent weight, roasting temperature 800 °C, dissolution at 1.5 M HCl concentration and 4 hours stirring time. Decomposition results using NaHCO₃ gave Y leaching results better (6.68 %) compared to Na₂CO₃ reagent (6.32 %). (author)

[en] The mixture of uranium and ruthenium was always found in the spent reactor nuclear fuel. Uranium extraction by organic extractant of high molecular weight known as AMEX process was studied in this paper. Feed of uranium - ruthenium mixture in HCl solution was extracted by tridodecylamine in toluene. The investigated parameter of the extraction is the acidity of feed solution, the concentration of tridodecylamine, the ratio volume of aqueous phase to organic phase and the extraction time. The optimum separation yield was obtained at condition of feed solution of 5M HCI with U = 22924 ppm and Ru = 1486 ppm extracted by using 0.5 M tridodecylamine in toluene, the ratio volume of aqueous phase to organic phase (FA:FO) = 1:1, the extraction time = 0.5 minutes. The efficiency of extraction U = 100% and organic extraction phase was relatively free of Ru

[en] Process of making yttrium oxide (Y₂O₃) through precipitation and calcination process from raw material xenotime sand has been done. Stages of the process include digestion, precipitation, and calcination. Xenotime sand digestion process carried out at a reaction temperature of 210 °C for 4 hours, the size of sand Xenotime 200-325 mesh, was merged with 96 % H₂SO₄ solution, and a solution of 30 % H₂O₂. Digestion product is a rare earth element (REE) concentrated that has been diluted with water - ice is used as feed precipitation process. There are two kinds of precipitation agent namely: 25 % NH₃ (aq) solution and the mixture 25 % NH₃ (aq) and 30 % (w/v) H₂C₂O₄ 30 % solutions. The product was analyzed using XRF spectrometer. The variables examined include pH of precipitation, temperature and time of calcination. The precipitation process used the solution of 25 % NH₃ (aq) at pH = 7 (multi precipitation), with this condition the concentration obtained concentration of Y = 59.42 %. The optimum conditions of calcination process were calcination temperature = 1000 °C and calcination time = 2 hours. (author)