scholarly journals Proliferation Resistance of Borosilicate Glass as a Host Form for Weapons-Grade Plutonium

1996 ◽  
Vol 465 ◽  
Author(s):  
G. S. Cerefice ◽  
K. W. Wenzel
Keyword(s):  
Rare Earth ◽  
Solvent Extraction ◽  
Borosilicate Glass ◽  
Glass Matrix ◽  
Critical Mass ◽  
Fission Products ◽  
Extraction Process ◽  
Dissolution Process ◽  
Acid Dissolution ◽  
Weapons Grade Plutonium

ABSTRACTTo examine the proliferation resistance of borosilicate glass, a process to extract and recover a plutonium analog (thorium) from borosilicate glass was developed and examined. The glass matrix examined was a modified standard frit consisting of the ARM-1 frit (with simulated fission products) loaded with 2 wt. % thorium (as an analog for plutonium) and 2 wt. % each of three rare earth elements (Gd, Sm, Eu), which were added for criticality control and to possibly increase the proliferation resistance of the glass matrix. The plutonium analog was extracted from the crushed glass with a nitric acid dissolution process, and subsequently decontaminated using a solvent extraction process. The acid dissolution process was able to extract 88.4 ± 6.8 % of the plutonium surrogate from the glass host form. The bench top solvent extraction process was 30.2 ± 10.9 % efficient in recovering the plutonium analog as a purified product. Overall, this process was able to extract 26.7 ± 9.9 % of the plutonium analog from the glass as a purified product. To quantify the proliferation resistance of borosilicate glass as a host form for weapons-grade plutonium, MCNP was used to determine the compressed critical mass of a plutonium alloy with the same composition as the product of the extraction process. For the average product composition, the compressed critical mass was 4.7 kg of material. On average, one compressed critical mass could be recovered from 613 kg of borosilicate glass (2 wt. % Pu loading).

scholarly journals Study on the Effect and Mechanism of Impurity Aluminum on the Solvent Extraction of Rare Earth Elements (Nd, Pr, La) by P204-P350 in Chloride Solution

Minerals ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 61
Author(s):  
Wenjie Zhang ◽  
Xian Xie ◽  
Xiong Tong ◽  
Yunpeng Du ◽  
Qiang Song ◽  
...  
Keyword(s):  
Rare Earth ◽  
Solvent Extraction ◽  
Rare Earth Elements ◽  
Organic Phase ◽  
Extraction Process ◽  
Industrial Applications ◽  
Separation And Purification ◽  
Aluminum Ion ◽  
Hydrochloric Acid Medium ◽  
Impurity Ion

Solvent extraction is the most widely used method for separation and purification of rare earth elements, and organic extractants such as di(2-ethylhexyl) phosphoric acid (P204) and di(1-methyl-heptyl) methyl phosphonate (P350) are most commonly used for industrial applications. However, the presence of impurity ions in the feed liquid during extraction can easily emulsify the extractant and affect the quality of rare earth products. Aluminum ion is the most common impurity ion in the feed liquid, and it is an important cause of emulsification of the extractant. In this study, the influence of aluminum ion was investigated on the extraction of light rare earth elements by the P204-P350 system in hydrochloric acid medium. The results show that Al3+ competes with light rare earths in the extraction process, reducing the overall extraction rate. In addition, the Al3+ stripping rate is low and there is continuous accumulation of Al3+ in the organic phase during the stripping process, affecting the extraction efficiency and even causing emulsification. The slope method and infrared detection were utilized to explore the formation of an extraction compound of Al3+ and the extractant P204-P350 that entered the organic phase as AlCl[(HA)2]2P350(o).

scholarly journals Rare Earth Extraction using Solvent Extraction: Which Factor Has the Most Significant Impact?

2020 ◽  
Vol 7 (2) ◽  
pp. 86-93
Author(s):  
Nurul Ain Ismail
Keyword(s):  
Rare Earth ◽  
Solvent Extraction ◽  
Factorial Design ◽  
Aqueous Phase ◽  
Extraction Process ◽  
Phase Ratio ◽  
Feed Composition ◽  
Five Factors ◽  
Acid Type ◽  
Rare Earth Extraction

Using a two-level factorial design, a study was undertaken to change the parameters impacting the recovery of rare earth from rare earth mixture. The experimental design was used to screen and identify the major contributing aspects to rare earth recovery. The experiment aims to isolate samarium from a mixture of samarium, europium, and gadolinium. Factors involved consist of pH (pH 1 and pH 6), acid type (nitric acid and hydrochloric acid) and concentration (1.0M and 5.0M), mixing duration (30 min and 120 min), feed composition (20% samarium and 80% samarium), type of diluent (hexane and chloroform), temperature (room temperature and 60°C) and organic to aqueous phase ratio (1:1 and 2:1). The results showed that the samarium recovery was in the range of 0.98% to 90.88%. Based on analysis variance (ANOVA), five factors significantly affect the samarium recovery out of eight factors explored. The five factors according to the most significant order are pH> feed composition> organic to aqueous phase ratio>acid concentration>acid type>mixing duration>type of diluent> temperature.  Statistical analysis shows that the linear model is significant, with the value of R2 is 0.9886. Based on the statistical data, five significant variables influence the separation of samarium. This research shows that two-level factorial design can anticipate significant variables impacting rare earth separation, particularly samarium, in the solvent extraction process.

Synthesis of Dihexyldithiophosphate Ligand and a Preliminary Study on Its Use for the Extraction of Gadolinium from Rare Earth Elements Mixture

2019 ◽  
Vol 829 ◽  
pp. 270-275
Author(s):  
Santhy Wyantuti ◽  
Uji Pratomo ◽  
Mira Aprilani ◽  
Anni Anggraeni ◽  
Husein H. Bahti
Keyword(s):  
Rare Earth ◽  
Solvent Extraction ◽  
Extraction Efficiency ◽  
Imaging Techniques ◽  
Extraction Process ◽  
Solvent Extraction Method ◽  
Before And After ◽  
Preliminary Study ◽  
Mixed Samples ◽  
The Rare Earth

Development of body imaging techniques for medical diagnosis has future promising. To improve the image visibility, Gadolinium (Gd) has been known as an important material for preparing the contrast agent. However, since the rare earth metals have unique physical properties, the separation of Gd from the other metals by a simple, effective and efficient method is still challenging. Hereby, we report the separation of Gd from the rare earth mixture with dihexyl dithiophosphate (DHDTP) ligand by solvent extraction method. The amount of Gd before and after the extraction process was determined with ICP-OES. The results show that the extraction efficiency for the mixed samples of Gd (III) and Sm (III) is 53.10% with 51.10% purity of Gd (III) and extraction efficiency for mixed samples of Gd (III) and Dy (III) is 93.82% with 50.35% purity of Gd (III). This result indicates that DHDTP can be used for solvent extraction of Gd.

scholarly journals Penentuan Kondisi Optimum Proses Ekstraksi Uranium dan Torium dari Terak II Timah dengan Metode Pelindian Asam Sulfat dan Solvent Extraction Trioctylamine (TOA)

EKSPLORIUM ◽  
2019 ◽  
Vol 40 (1) ◽  
pp. 11
Author(s):  
Mutia Anggraini ◽  
Fuad Wafa Nawawi ◽  
Kurnia Setiawan Widana
Keyword(s):  
Rare Earth ◽  
Solvent Extraction ◽  
Rare Earth Elements ◽  
Organic Phase ◽  
Mixing Time ◽  
Economic Value ◽  
Extraction Process ◽  
Radioactive Elements ◽  
Tin Slag ◽  
Slag Processing

ABSTRAKTerak II timah merupakan produk hasil samping dari peleburan timah tahap kedua. Terak II timah ini mengandung unsur bernilai ekonomi tinggi berupa unsur radioaktif (uranium dan torium) dan logam tanah jarang (rare earth element). Unsur-unsur tersebut dapat dimanfaatkan apabila telah terpisah satu dengan lainnya. Proses pemisahan unsur radioaktif dan unsur logam tanah jarang telah dilakukan dengan metode pelindian asam sulfat. Hasil proses ini adalah endapan yang mengandung logam tanah jarang dan filtrat yang mengandung unsur radioaktif berupa uranium dan torium sulfat. Penelitian terkait pemisahan uranium dan torium hasil pengolahan terak II timah hanya sedikit dipublikasikan. Paper ini bertujuan untuk mengetahui efektifitas proses pemisahan uranium dan torium dengan metode solvent extraction menggunakan trioctylamine (TOA). Proses solvent extraction dilakukan dengan memvariasikan konsentrasi TOA yang digunakan, perbandingan fase aqueous dan fase organik (A/O) dan variasi waktu ekstraksi. Pada penelitian ini diperoleh kondisi optimum proses yaitu konsentrasi TOA 4%, perbandingan A/O 1 : 1, dan waktu pencampuran aqueous dan organik selama 2 menit. Pada kondisi ini uranium dan torium yang terekstrak masing-masing sebanyak 67% dan 0,84%. ABSTRACTTin 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.

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