• Nuclear Engineering and Technology
• /
• v.47 no.5
• /
• pp.588-595
• /
• 2015

This study presents an effective method for additional recovery of residual actinides in liquid electrodes after the electrowinning process of pyroprocessing. The major distinctive feature of this method is a reactor with multiple reaction cells separated by partition walls in order to improve the recovery yield, thereby using the interelement difference in diffusion coefficients within the liquid electrode and controlling the selectivity and purity of element recovery. Through an example of numerical simulation of the diffusion scenarios of individual elements, we verified that the proposed method could effectively separate the actinides (U and Pu) and rare-earth elements contained in liquid cadmium. We performed a five-step consecutive recovery process using a simplified conceptual reaction cell and recovered 58% of the initial amount of actinides (U + Pu) in high purity (${\geq}99%$).

• Resources Recycling
• /
• v.27 no.4
• /
• pp.65-69
• /
• 2018

In solvent extraction, extraction isotherm represents the relation between the equilibrium concentration of metal in the aqueous and organic phase. McCabe-Thiele diagram on which extraction isotherm and operating line are constructed provides valuable information on the mass transfer operation. When the equilibrium constant of a solvent extraction reaction is known, the calculation method to obtain extraction isotherm was introduced. Kresmer equation by which the number of extraction stages can be calculated when the distribution coefficient is constant was introduced.

• Proceedings of the Korean Radioactive Waste Society Conference
• /
• 2018.05a
• /
• pp.51-52
• /
• 2018

Selective oxidation of RE elements from the U/RE metal ingot was studied in this paper using electrochemical process. Constant potential of -1.7V was applied between anode and cathode, where the potential value corresponds to standard potentials between actinide and rare earth materials. When the current values approached to nearly 0 mA, the reaction was finished. It is confirmed from the EPMA analysis that only U part of the U/RE ingot was remained. The metal recovered to the zinc cathode was obtained through the distillation process and it is being chemically analyzed in the KAERI analytical laboratory.

• Journal of Powder Materials
• /
• v.21 no.4
• /
• pp.313-317
• /
• 2014

• Journal of the Korean Chemical Society
• /
• v.49 no.3
• /
• pp.261-268
• /
• 2005

• Proceedings of the Korean Radioactive Waste Society Conference
• /
• 2004.06a
• /
• pp.339-339
• /
• 2004

원자로를 이용하여 장수명핵종(long lived nucleus)을 소멸처리하는 과정에서 초우라늄(TRU, transuranium)과 희토류(RE, rare earth) 금속에 포함되어 있는 소량의 핵분열성(fissile) 물질인 우라늄을 제거할 필요가 있다. 본 실험은 LiCl-KCl 용융염계에서 전해제련법(Electrowinning)을 이용하여 용융염욕에 존재하는 우라늄을 제거하기 위하여 필요한 Cd-Li 양전극 물질을 제조하였고, 제조된 금속을 이용하여 우라늄 및 란탄족(Dy, Ce, Y, Nd, Gd) 금속의 환원 특성을 파악하였다.(중략)

• Proceedings of the Korean Powder Metallurgy Institute Conference
• /
• 2006.09b
• /
• pp.712-713
• /
• 2006

We successfully developed Al-Si-Transition Metal (TM) -Rare Earth (RE) Powder Metallurgy (P/M) alloy with fine microstructure, which has high strength at high temperature. This material was compacted rapidly solidified powder and directly consolidated by hot extruding or forging. Before consolidating, rapid heating was performed on powder compaction in order to keep the fine microstructure in powder state. We have also investigated the processing conditions of this new alloy by computing simulations and experiments.

• Bulletin of the Korean Chemical Society
• /
• v.34 no.5
• /
• pp.1579-1582
• /
• 2013

• Journal of Korean Vacuum Science & Technology
• /
• v.7 no.1
• /
• pp.18-22
• /
• 2003

The optogalvanic effect is proposed and demonstrated as a technique for Penning ionization in a discharge of mixtures of metal vapors and rare gases. The gadolinium and argon mixture is used as a prototype. The lowest metastable of argon, 3P$_2$ (ls$\_$5/ in Paschen notation) at 93144 cm$\^$-1/, is within kT from the excited states of Gd ion. Thus Penning ionization occurs to an excited states of the ion. This process strongly alters the optogalvanic signal and has its own signatures.

• Proceedings of the KSEEG Conference
• /
• 2003.04a
• /
• pp.201-208
• /
• 2003

지각내의 한 장소에 농집되어 나타나는 정도가 희소(稀少)한 원소 또는 금속을 총칭하여 희유금속(稀有金屬) 이라고 하며, 산업용으로만 이용되어 온 희유금속은 천연에서의 산출부족으로 뒤늦게 발견되었고, 일반 수요의 결핍, 추출과정의 어려움 등의 이유로 “희유원소” 라는 용어는 시대적으로 채택된 하나의 개념으로, 20세기초에 들어와서야 비로소 산업의 필요성이 나타나기 시작하였다. (중략)