(1. 內(nèi)蒙古科技大學(xué) 礦業(yè)研究院，包頭 014010； 2. 內(nèi)蒙古科技大學(xué) 內(nèi)蒙古自治區(qū)白云鄂博礦多金屬資源綜合利用重點(diǎn)實(shí)驗(yàn)室，包頭 014010)
摘 要: 通過純礦物浮選、Zeta 電位測試、溶液化學(xué)計算、紅外光譜分析及XPS測試，研究以羥肟酸為捕收劑浮選稀土?xí)rCe3+離子對螢石的活化作用機(jī)理。結(jié)果表明：礦漿中Ce3+離子濃度低于羥肟酸時在pH 6~12對螢石都具有活化作用，其活化機(jī)理為Ce3+離子吸附提高螢石表面的正電性，增強(qiáng)螢石表面與陰離子羥肟酸捕收劑的靜電吸附作用，且在螢石表面形成F-Ce(OH)2/Ce(OH)+活性位點(diǎn)。紅外光譜和XPS測試表明，無Ce3+離子活化時，辛基羥肟酸在螢石表面主要生成不穩(wěn)定的四元環(huán)絡(luò)合物—C—O—Ca—N—，羥肟酸與Ca2+離子結(jié)合能小，直接在螢石表面的吸附作用弱；被Ce3+離子活化后，辛基羥肟酸與螢石表面Ce3+離子反應(yīng)生成穩(wěn)定的五元環(huán)絡(luò)合物—C= O—Ce—O—N—，羥肟酸與Ce3+離子結(jié)合能大，加強(qiáng)羥肟酸在螢石表面的吸附作用，從而使螢石被活化。
關(guān)鍵字: 稀土；浮選；Ce3+離子；螢石；活化
（1. Institute of Mining Engineering, Inner Mongolia University of Science and Technology, Baotou 014010, China; 2. Key Laboratory of Integrated Exploitation of Bayan Obo Multi-Metal Resources, Inner Mongolia University of Science and Technology, Baotou 014010, China）
Abstract:The activation mechanism of Ce3+ on fluorite using octanohydroxamic acid (OHA) as rare earth flotation collector was studied by pure mineral floatation experiment, Zeta potential measurement, solution chemistry analysis, infrared( IR) spectra and XPS measurements. The results show that fluorite can be activated at pH 6-12 when the concentration of Ce3+ is lower than that of OHA, the activation mechanism is that the positive potential of fluorite is improved by adsorbing of Ce3+onto its surface, thus enhancing the electrostatic adsorption of anionic hydroxmic acid collector on fluorite, and moreover F-Ce(OH)2/Ce(OH)+ active site can be formed on the surface of fluorite. IR spectra and XPS measurements show that an unstable four-member ring chelate complex —C—O—Ca—N— is generated when OHA reacts with fluorite without Ce3+ activation, the binding energy of OHA with Ca2+ is low, which leads to a weak adsorption of OHA onto fluorite. A stable five-member ring chelate complex —C=O—Ce—O—N— forms when OHA reacts with Ce3+ activated fluorite, the binding energy of OHA with Ce3+ is high, which enhances the adsorption of OHA onto fluorite and thus activates the flotation of fluorite.
Key words: rare earth; flotation; Ce3+ ion; fluorite; activation
