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dc.contributor.advisorZhang, Jinhongen
dc.contributor.authorAn, Dongbo*
dc.creatorAn, Dongboen
dc.date.accessioned2017-06-21T16:14:43Z
dc.date.available2017-06-21T16:14:43Z
dc.date.issued2017
dc.identifier.urihttp://hdl.handle.net/10150/624299
dc.description.abstractThe present study is targeted on the optimization of the flotation conditions for the improvement of the industrial flotation practice. Part I is focused on the improvement of the flotation of Mountain Pass mine ore for the beneficiation of rare earth elements. The objective is to improve the rare earth recovery of Mountain Pass ore by developing a novel flotation reagents' scheme, meanwhile reducing the flotation temperature to a cost-efficient level and simplifying the flowsheet. Surface chemistry study by contact angle, zeta potential and microflotation tests indicate that a mixed collector consisting of oleic acid (OA) and sodium octanohydroxamate hydrate (OHA) is beneficial for rare earth flotation. More importantly, salicylhydroxamic acid (SHA) is also a promising collector due to the high selectivity. Lab-scale flotation tests using SHA as collector show that 80-90% REE recovery and <20% gangue recovery are achieved at 40°C~60°C, which yield a rougher concentrate of 30%~40% REO. A novel flotation scheme has been developed towards Mountain Pass rare earth mine. The new scheme is of both high selectivity and high recovery, meanwhile the dosage of reagent required is much less, and the flotation temperature is also significantly reduced. Interactive adsorption models are built up through FT-IR and AFM study. The interaction of collector with bastnaesite surface is illustrated. Hydroxamic acid collectors (OHA and SHA) adsorb on bastnaesite surface by forming stable chelating complex. The selectivity of collectors towards bastnaesite flotation is summarized as SHA>OHA>OA. Part II is focused on the improvement of the flotation of Resolution Copper's Superior mine ore at an elevated temperature for the beneficiation of chalcopyrite. Because the Resolution Copper ore is mined from a deep, hot, underground mine, the temperature of ROM (run of mine ore) is much higher than that of the ore usually processed in a typical open-pit copper mine. The ore temperature will still be high during flotation. It is therefore critical to carry out a systemic study on the flotation of Resolution Copper ore at elevated temperatures and clarify the impact on flotation. An overall beneficial effect is observed in high temperature flotation through a lab-scale flotation study. Further action of temperature control is not necessary. The contact angle results indicate that surface hydrophobicity is enhanced at elevated temperature, of which the surface morphology change (shown by AFM images) of xanthate adsorption species (dixanthogen) is the key factor.
dc.language.isoen_USen
dc.publisherThe University of Arizona.en
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en
dc.subjectBastnaesiteen
dc.subjectchalcopyriteen
dc.subjectflotationen
dc.subjecthydroxamic aciden
dc.subjectrare earthen
dc.subjecttemperatureen
dc.titleImproved Flotation of Bastnaesite and Chalcopyriteen_US
dc.typetexten
dc.typeElectronic Dissertationen
thesis.degree.grantorUniversity of Arizonaen
thesis.degree.leveldoctoralen
dc.contributor.committeememberZhang, Jinhongen
dc.contributor.committeememberRaghavan, Srinien
dc.contributor.committeememberLee, Jaeheonen
dc.contributor.committeememberTenorio, Victor Octavioen
dc.description.releaseRelease after 01-May-2019en
thesis.degree.disciplineGraduate Collegeen
thesis.degree.disciplineMining Geological & Geophysical Engineeringen
thesis.degree.namePh.D.en
html.description.abstractThe present study is targeted on the optimization of the flotation conditions for the improvement of the industrial flotation practice. Part I is focused on the improvement of the flotation of Mountain Pass mine ore for the beneficiation of rare earth elements. The objective is to improve the rare earth recovery of Mountain Pass ore by developing a novel flotation reagents' scheme, meanwhile reducing the flotation temperature to a cost-efficient level and simplifying the flowsheet. Surface chemistry study by contact angle, zeta potential and microflotation tests indicate that a mixed collector consisting of oleic acid (OA) and sodium octanohydroxamate hydrate (OHA) is beneficial for rare earth flotation. More importantly, salicylhydroxamic acid (SHA) is also a promising collector due to the high selectivity. Lab-scale flotation tests using SHA as collector show that 80-90% REE recovery and <20% gangue recovery are achieved at 40°C~60°C, which yield a rougher concentrate of 30%~40% REO. A novel flotation scheme has been developed towards Mountain Pass rare earth mine. The new scheme is of both high selectivity and high recovery, meanwhile the dosage of reagent required is much less, and the flotation temperature is also significantly reduced. Interactive adsorption models are built up through FT-IR and AFM study. The interaction of collector with bastnaesite surface is illustrated. Hydroxamic acid collectors (OHA and SHA) adsorb on bastnaesite surface by forming stable chelating complex. The selectivity of collectors towards bastnaesite flotation is summarized as SHA>OHA>OA. Part II is focused on the improvement of the flotation of Resolution Copper's Superior mine ore at an elevated temperature for the beneficiation of chalcopyrite. Because the Resolution Copper ore is mined from a deep, hot, underground mine, the temperature of ROM (run of mine ore) is much higher than that of the ore usually processed in a typical open-pit copper mine. The ore temperature will still be high during flotation. It is therefore critical to carry out a systemic study on the flotation of Resolution Copper ore at elevated temperatures and clarify the impact on flotation. An overall beneficial effect is observed in high temperature flotation through a lab-scale flotation study. Further action of temperature control is not necessary. The contact angle results indicate that surface hydrophobicity is enhanced at elevated temperature, of which the surface morphology change (shown by AFM images) of xanthate adsorption species (dixanthogen) is the key factor.


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