Asynchronous Flotation for Wolframite,Scheelite and Other Calcium-containing Minerals

Based on the flotation tests for single mineral and artificial composite ores,the effective separation of wolframite,scheelite and other calcium-containing minerals by asynchronous flotation was studied.The function mechanism was discussed by XPS,AAS,crystal chemistry and solution chemistry analysis.The results show that,benzohydroxamic acid(BHA) is a selective collector for the minerals in the following floatability sequence: wolframitescheeliteother calcium-containing minerals.Citrate acid can be used as a selective regulator for wolframite preferential flotation due to its selective depression.Citrate acid can not be firmly adsorbed on the surface of wolframite,resulting in the adsorption of BHA on its surface.Meanwhile,citrate acid can coordinate selectively with calcium ions on scheelite and other calcium-containing minerals,resulting in the active points on these minerals for collector adsorption decreased,thus the floatability of these minerals depressed.