(1. 内蒙古科技大学 矿业研究院，包头 014010；
2. 广东省资源综合利用研究所，广州 510650；
3. 稀有金属分离与综合利用国家重点实验室，广州 510650；
4. 中南大学 资源与生物工程学院，长沙 410083)
摘 要: 通过密度泛函理论(DFT/B3LYP)计算，分析辛基羟肟酸(OHA)和油酸(OA)两种捕收剂的结构构型、前线分子轨道、Mulliken电荷布局以及与Ca2+/Ce3+离子之间的结合能，并通过纯矿物浮选对比研究OHA和OA对氟碳铈矿和萤石的浮选性能。量化计算结果表明：OHA阴离子具有最高的键合原子负电荷、最高占据分子轨道(HOMO)能量和最低的EHOMO-LUMO能隙，比OA具有更强的给电子能力和反应活性；OHA、OA与Ca2+/Ce3+离子之间结合能从强到弱顺序为OHA-Ce、OA-Ce、OA-Ca、OHA-Ca，即OHA与Ce3+结合能最大，且对Ca2+/Ce3+两种离子的结合能差异最大。浮选结果表明：OHA对氟碳铈矿浮选的捕收能力和选择性都大于OA的，与量化计算结果规律一致。
关键字: 稀土矿物；捕收剂；密度泛函理论；浮选分离；前线分子轨道
（1. Institute of Mining Engineering, Inner Mongolia University of Science and Technology, Baotou 014010, China;
2. Guangdong Institute of Resources Comprehensive Utilization, Guangzhou 510650, China;
3. State Key Laboratory of Rare Metals Separation and Comprehensive Utilization, Guangzhou 510650, China
4. School of Minerals Processing and Bioengineering, Central South University, Changsha 410083, China）
Abstract:The density functional theory (DFT/B3LYP) calculation was carried out to analyze the geometric structure, frontier molecular orbital and Mulliken charge values of octyl hydroxamic acid (OHA) and oleic acid (OA) as well as their respective binding energy with Ca2+ and Ce3+ ions. Besides, pure mineral flotation was used to compare the flotation performances of OHA and OA for bastnasite and fluorite. The DFT calculation results show that OHA anion has the highest binding atom charge, the strongest HOMO energy and the lowest EHOMO-LUMO energy gap, thus performing stronger electron donating ability and reactivity than OA; the binding energy strength decreases in such order as OHA-Ce, OA-Ce, OA-Ca and OHA-Ca. In other words, OHA has the biggest binding energy with Ce3+ and largest binding energy difference for Ca2+ and Ce3+ ions. The flotation results show that OHA behaves stronger collection capacity and selectivity than OA, which is consistent with the DFT calculation results.
Key words: rare earth mineral; collector; density functional theory; flotation separation; frontier molecular orbital
