SEPARATION METHOD OF MINOR ACTINOID

• Main Authors: HOSHINO KUNIYOSHI, KANI YUKO, WATANABE DAISUKE
• Format: Patent
• Language: English; Japanese
• Published: 14.03.2019
• Subjects: CHEMISTRY; COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSESC01D OR C01F; INORGANIC CHEMISTRY; METALLURGY; NUCLEAR ENGINEERING; NUCLEAR PHYSICS; NUCLEAR REACTORS; PERFORMING OPERATIONS; PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL; PHYSICS; SEPARATION; TRANSPORTING

To provide a separation method of a minor actinoid (hereinafter referred to as MA) which improves a yield and reduces a scale of the whole facility.SOLUTION: A separation method of MA includes: an extraction process of extracting MA into an organic phase by bringing the organic phase formed of an extract which is a solution dissolving a complexing agent in an organic solvent into contact with a first aqueous phase containing an aqueous solution containing MA; a cleaning process of moving MA contained in the organic phase to a cleaning solution by bringing the organic phase acquired in the extraction process into contact with the cleaning solution; and a reverse extraction process of extracting MA contained in an MA contained extraction liquid by bringing the MA contained extraction liquid which is the organic phase acquired in the cleaning process into contact with a reverse extraction liquid. The separation method of MA includes the following features. (1) Between the cleaning process and the reverse extraction process, there is an acid removal process further included which moves the acid contained in the MA contained extraction liquid by bringing the MA contained extraction liquid into contact with a second aqueous phase of the water or an alkaline aqueous solution. (2) A process of adding the alkaline aqueous solution to the reverse extraction liquid is further included.SELECTED DRAWING: Figure 2 【課題】回収率を向上するとともに設備全体の規模を縮小するマイナーアクチノイド（以下ＭＡという）の分離方法を提供する。【解決手段】有機溶媒に錯化剤を溶解した溶液である抽出液からなる有機相と、ＭＡを含む水溶液を含む第一の水相と、を接触させてＭＡを有機相に抽出する抽出工程と、抽出工程で得られた有機相と、洗浄液と、を接触させて有機相に含まれるＭＡを洗浄液に移動させる洗浄工程と、洗浄工程で得られた有機相であるＭＡ含有抽出液と、逆抽出液と、を接触させてＭＡ含有抽出液に含まれるＭＡを逆抽出液に抽出する逆抽出工程と、を含むＭＡの分離方法であって、次の特徴を有する。（１）洗浄工程と逆抽出工程との間には、ＭＡ含有抽出液に水又はアルカリ性水溶液の第二の水相を接触させてＭＡ含有抽出液に含まれる酸を第二の水相に移動させる酸除去工程を更に含む。（２）逆抽出液にアルカリ性水溶液を添加する工程を更に含む。【選択図】図２