The influence of temperature on the complex process of Bayan Obo rare earth (RE) ore flotation with a collector of naphthyl hydroxamic acid (LF8#) was investigated. Industrial test data shows that the grade and re...The influence of temperature on the complex process of Bayan Obo rare earth (RE) ore flotation with a collector of naphthyl hydroxamic acid (LF8#) was investigated. Industrial test data shows that the grade and recovery of RE increase with the temperature. However, the proportion of bastnaesite in the bulk concentrate increases as the RE grade improves. Adsorption mechanism of LF8# on the surfaces of bastnaesite and monazite were confirmed via zeta potential, UV]Vis Spectrophotometer (UV]Vis), Fourier transform infrared (FIR), and X-ray photoelectron spectroscopy analyses (XPS). Although the results indicate that the total amount of the LF8# adsorption on the surface of bastnaesite and monazite de- creases with increasing the temperature, the amount of stable adsorbed predominance of characteristic bonds (-C(~O)N-] from LF8# uptake on bastnaesite surfaces increases significantly at high tempera- tures. This conclusion indicates that the adsorption stability increases with increasing the temperature. For monazite, the amount of characteristic elements C and N in LF8# does not increase as the temper- ature increases on the mineral surface, but the proportion of characteristic bonds increases, which shows that the adsorption stability of LF8# on the surface of monazite also increases, but it is not as significant as bastnaesite, which may be one of the reasons that the floatability of bastnaesite is better than those of monazite. Pulp dispersion results show that the temperature improve the dispersions of both the gangue and RE minerals. This improved the flotation selectivity so that it favored RE minerals. The calculated bubble size distribution confirms that higher temperatures generate smaller bubbles, thereby increasing the bubble-particle collision probability and the recovery of RE minerals.展开更多
基金Project supported by the National Natural Science Foundation of China(51634005,51564042)the Natural Science Foundation of Inner Mongolia Autonomous Region of China(2016ZD05,2014ZD04)
文摘The influence of temperature on the complex process of Bayan Obo rare earth (RE) ore flotation with a collector of naphthyl hydroxamic acid (LF8#) was investigated. Industrial test data shows that the grade and recovery of RE increase with the temperature. However, the proportion of bastnaesite in the bulk concentrate increases as the RE grade improves. Adsorption mechanism of LF8# on the surfaces of bastnaesite and monazite were confirmed via zeta potential, UV]Vis Spectrophotometer (UV]Vis), Fourier transform infrared (FIR), and X-ray photoelectron spectroscopy analyses (XPS). Although the results indicate that the total amount of the LF8# adsorption on the surface of bastnaesite and monazite de- creases with increasing the temperature, the amount of stable adsorbed predominance of characteristic bonds (-C(~O)N-] from LF8# uptake on bastnaesite surfaces increases significantly at high tempera- tures. This conclusion indicates that the adsorption stability increases with increasing the temperature. For monazite, the amount of characteristic elements C and N in LF8# does not increase as the temper- ature increases on the mineral surface, but the proportion of characteristic bonds increases, which shows that the adsorption stability of LF8# on the surface of monazite also increases, but it is not as significant as bastnaesite, which may be one of the reasons that the floatability of bastnaesite is better than those of monazite. Pulp dispersion results show that the temperature improve the dispersions of both the gangue and RE minerals. This improved the flotation selectivity so that it favored RE minerals. The calculated bubble size distribution confirms that higher temperatures generate smaller bubbles, thereby increasing the bubble-particle collision probability and the recovery of RE minerals.