Separation and Recycling for Rare Earth Elements by Homogeneous Liquid-Liquid Extraction (HoLLE) Using a pH-Responsive Fluorine-Based Surfactant
A selective separation and recycling system for metal ions was developed by homogeneous liquid-liquid extraction (HoLLE) using a fluorosurfactant. Sixty-two different elemental ions (e.g., Ag, Al, As, Au, B, Ba, Be, Bi, Ca, Cd, Ce, Co, Cr, Cu, Dy, Er, Eu, Fe, Ga, Gd, Ge, Hf, Hg, Ho, In, Ir, La, Lu, Mg, Mn, Mo, Nb, Nd, Ni, Os, P, Pb, Pd, Pr, Pt, Re, Rh, Ru, Sb, Sc, Se, Si, Sm, Sn, Sr, Ta, Tb, Te, Ti, Tl, Tm, V, W, Y, Yb, Zn, and Zr) were examined. By changing pH from a neutral or alkaline solution (pH ≥ 6.5) to that of an acidic solution (pH 90% efficiency into a sedimented Zonyl FSA® (CF3(CF2)n(CH2)2S(CH2)2COOH, n = 6–8) liquid phase. Moreover, all rare earth elements were obtained with superior extraction and stripping percentages. In the recycling of rare earth elements, the sedimented phase was maintained using a filter along with a mixed solution of THF and 1 M sodium hydroxide aqueous solution. The Zonyl FSA® was filtrated and the rare earth elements were recovered on the filter as a hydroxide. Furthermore, the filtrated Zonyl FSA was reusable by conditioning the subject pH.
金属-1,10-フェナントロリンキレートの弱酸性領域での均一液液抽出法
均一液液抽出法における弱酸性領域での相分離条件について検討した．相分離剤としてZonyl FSA，キレート剤として1,10-フェナントロリン，水溶性有機溶媒としてアセトンを用いることで，弱酸性領域（pH 2近傍）でのAl，Cu，Tiなど14元素についての相分離が可能となった．50 v/v％ Zonyl FSA添加量1 mlに対して相分離した析出相体積は100 μlであった．本法による各元素の回収率は約95％ 以上で良好な結果が得られた．弱酸性領域では多種にわたるキレート剤を使用することが可能であり，均一液液抽出法の適用枠の拡大が期待できる．
The Establishment of Communist Rule in Poland, 1943-1948.
First published underground in Poland in 1984, this inside look at Communist subjugation is now available to the English reader. Nowhere has the takeover of any East-Central European country been so searchingly documented by a writer who was living at the time under the imposed Communist regime. Kersten's political analysis and bright narrative will inspire anyone interested in contemporary European history. The author assiduously details the Communist Party's manipulation of Polish society, media, and politics. With remarkable objectivity she depicts the political scene during the critical period from the final years of World War II to the consolidation of Stalinism at the end of 1948.