Quartz and feldspar are the primary impurities in the mineral processing of pollucite. Due to the highly similar surface properties of these three minerals in terms of physicochemical characteristics, achieving efficient flotation enrichment of pollucite has been a challenging problem. To address this issue, the development of flotation collectors with high selectivity towards pollucite is crucial. In this study, different-sized crown ethers acted as selective collectors for the direct flotation to detach pollucite from feldspar and quartz were investigated, leveraging the selective bonding of crown ethers to alkali metal active site on the surface of pollucite. The properties of 21-crown-7 ether (21C7), benzo-21-crown-7 (B21C7) and dibenzo-21-crown-7 (DB21C7) (with three different cavity sizes) were investigated as collectors for pollucite flotation. The experimental results indicated that DB21C7 exhibited the best collecting performance. The mechanism was studied through various experimental measurements and computational simulations, and the results revealed that the selective adsorption mechanism of crown ethers onto the surface of pollucite was achieved through a combination of chelation interaction involving “spatial effect” and hydrogen bonding interaction. This work has disclosed that crown ether compounds may hold significant potential as collectors for flotation of pollucite.

中文翻译：

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利用冠醚作为选择性捕收剂，用于从长石和石英中浮选分离污染物


石英和长石是污染物矿物加工中的主要杂质。由于这三种矿物在物理化学特性方面的表面性质高度相似，实现污染物的高效浮选富集一直是一个具有挑战性的问题。为了解决这个问题，开发对污染物具有高选择性的浮选捕收剂至关重要。在本研究中，利用冠醚与污染物表面碱金属活性位点的选择性键合，研究了不同尺寸的冠醚作为直接浮选从长石和石英中分离污染物的方法。研究了 21-冠-7 醚 （21C7）、苯并-21-冠-7 （B21C7） 和二苯并-21-冠-7 （DB21C7）（具有三种不同腔体尺寸）作为污染物浮选捕收剂的性质。实验结果表明，DB21C7 表现出最佳的收集性能。通过各种实验测量和计算模拟研究了该机制，结果表明，冠醚对污染石表面的选择性吸附机制是通过涉及“空间效应”的螯合相互作用和氢键相互作用相结合来实现的。这项工作揭示了冠醚化合物作为浮选污染物浮选剂可能具有巨大的潜力。