Study On The Joint Separation Technology Of Ilmenite Coastal Placer

The reserves of ilmenite in China are relatively rich. There are also abundant reserves of placer titanium in Beihai city, Guangxi province. However, because of the lag in technology, the beneficiation recovery of these ores was low, which the recovery was only around 50% when the grade of TiO2 reached 46%. Therefore, improving the recovery of placer titanium plays an important part in efficient utilization of titanium resources.As for Beihai placer titanium of Guangxi province, we firstly carried out studies on process mineralogy characteristics, followed by series of experimental researches on mineral processing such as gravity separation, high intensity magnetic separation, flotation of tailings of gravity separation and magnetic separation, open circuit experiment, closed circuit experiment and the research about the flotation mechanism. The test results indicate that, the suitable technological process for placer titanium separation is, namely, gravity separation-high intensity magnetic separation-flotation separation associated process. For the raw ores, by single-stage roughing-single-stage cleaning of gravity separation, titanium concentrate can be obtained with grade of 49.02% and recovery of 28.49% with rougher middling and rougher tailings. For the rougher middling, by high intensity magnetic separation, titanium concentrate can be obtained with grade of 48.75% and recovery of 55.51% with high intensity magnetic separation tailings. For the gravity separation rougher tailings and high intensity magnetic separation tailings, by single-stage roughing-two-stage cleaning of closed circuit flotation process, using sodium oleate as collector, sulfuric acid and sodium silicate as regulator, Pb(NO3)2 as activator, titanium concentrate can be obtained with grade of 39.55% and recovery of 14.95%. The final comprehensive concentrate can be obtained with TiO2 grade of 47.80%, and the recovery of 87.57%.The interaction of sodium oleate with ilmenite was studied by mineral surface potential and infrared spectrum analysis. Mineral surface potential shows that under acid condition, the surface of titanium is negatively charged and sodium oleate is the anionic collector, thus sodium oleate adsorbs onto ilmenite surface with chemical absorption rather than electrostatic adsorption. Infrared spectrum shows that there are new absorption peaks in the reaction product of sodium oleate and ilmenite, which indicates that chemical absorption occurs when sodium oleate adsorbs onto ilmenite surface.The results of this study laid a solid foundation for the high efficiency utilization of placer titanium resources and provided a good reference for the comprehensive recovery for the same type ores.