Study On Enhancing Flotation Behavior Of Argillaceous Smithsonite With Novle Dispersant

As the main mineral of zinc oxide ore,the flotation separation of smithsonite has attracted extensive attention.However,smithsonite is often accompanied by primary clay ore,which is easy to form fine particles in the process of transportation and grinding,and thereby seriously worsens the flotation of smithsonite.For the smithsonite mixed with clay minerals,the common solution to achieve better flotation efficiency is by desliming the clays before flotation.However,pre-desliming often causes the loss of zinc metal.Therefore,it is necessary using appropriate adjusting agents in non-desliming flotation of smithsonite to reduce the adverse effect of slime on the flotation of smithsonite.In this study,effects of fine clay minerals(kaolin and chlorite)on smithsonite flotation were studied using the sodium oleate or octadecylamine as the collectors.Two novel dispersants of sodium ligninsulfonate(SLS)and cetylpyridine bromide(CPB)were developed to enhance the flotation recovery of smithsonite in the presence of kaolin or chlorite fine particles.The floatation mechanism was analyzed and revealed.The main results are as follows:(1)The flotation tests of pure smithsonite minerals and smithsonite mixed with kaolin and chlorite were carried out.Sodium oleate and octadecylamine have good selectivity for smithsonite,but in the smithsonite mixed with clay flotation,kaolin and chlorite seriously affect the flotation of smithsonite.When the content of fine-grained kaolin and chlorite was10%,the productivity of smithsonite was reduced from 90% to 20%-40%,which was due to the serious covering of fine-grained kaolin and chlorite on the surface of smithsonite.(2)Two novel dispersants were developed to enhance the flotation recovery of smithsonite in the presence of kaolin or chlorite fine particles.SLS was used as the dispersant when sodium oleate was employed as the collector,while CPB was used for the octadecylamine collector system.It was found both the dispersants could greatly weaken or even eliminate the covering of fine kaolin or chlorite on the surface of smithsonite,and greatly increased the productivity of smithsonite to more than 80%.(3)The slime-coating of fine clays on the surface of smithsonite was mainly caused by hydrophobic attraction between the minerals.During the flotation,collectors of sodium oleate or octadecylamine were adsorbed on the surface of smithsonite and clays,resulting in the enhancement of the surface hydrophobicity of the minerals and strong hydrophobic attraction were produced between smithsonite and clay,which leaded to the seriously sime-coating of clay particles on the surface of smithsonite.After adding the dispersants of SLS or CPB,hydrophobic attraction between smithsonite and clay particles was eliminated due to the pre-adsorption of SLS or CPB on the clay surface.As a result,the slime-coating of fine clays on the surface of smithsonite was weakened or even eliminated,which significantly improved the flotation productivity of smithsonite.