This paper presents for the first time the application of aqueous two-phase systems for yttrium recovery from fluorescent lamp residues, a rare earth element with high added value and widely used in the technology industry. A multivariate study was carried out, using experimental design, for yttrium extraction employing ATPS using alizarin red as extracting agent, in order to expand the possibilities of the ATPS application in industrial scales. The optimized variables, employing 2^6–1 fractional design, were pH (3.00 to 9.00), extracting agent concentration (2.3 to 23.0 mmol kg^–1), tie-line length (TLL), ATPS-forming copolymers (L35 and L64) and electrolytes (Na₂SO₄ and C₆H₅Na₃O₇.2H₂O), and mass ratio between top and bottom phases (m_TP/m_BP = 0.5–2.0). It was observed for the first time, that the metal ions partition in ATPS is mainly influenced by the salt-forming anion species distribution as a function of pH at high TLL values. The extraction of yttrium was optimized in a 2³ factorial design with no lack of adjustment and it was able to predict the extraction response with accuracy close to 96%. The optimized conditions of yttrium extraction were applied using a leach liquor from real sample of fluorescent powder. After five extraction steps, 90% of yttrium was selectively recovered.

本文首次介绍了水相两相系统在荧光灯残渣中回收钇的应用，荧光灯残渣是一种具有高附加值的稀土元素，已广泛应用于技术行业。使用实验设计，对使用ATPS的茜素红作为萃取剂的钇萃取进行了多变量研究，以扩大ATPS在工业规模中的应用可能性。采用2 ^6–1分数设计的最佳变量是pH（3.00至9.00），萃取剂浓度（2.3至23.0 mmol kg ^–1），连接线长度（TLL），形成ATPS的共聚物（L35和L64）和电解质（Na ₂ SO ₄和C ₆ H ₅ Na₃ O ₇ .2H ₂ O），顶相和底相之间的质量比（m _TP / m _BP = 0.5–2.0）。首次观察到，在高TLL值下，ATPS中的金属离子分配主要受成盐阴离子种类分布的影响，该分布与pH有关。钇的萃取在2 ³因数设计中进行了优化，并且没有任何调整，它能够以接近96％的准确度预测萃取响应。使用浸出液从荧光粉的真实样品中提取钇的最佳条件。在五个提取步骤之后，选择性地回收了90％的钇。