Study On The Flotation Characteristics Of Cassiterite,Calcite And Quartz By Yeast

Cassiterite is brittle and easy to excessive friction,resulting in large number of fine cassiterite.It is difficult to recovery by gravity separation.Flotation can improve the recovery effect of fine cassiterite,and the flotation reagent is the key to effective recovery of cassiterite.Yeast has certain feasibility as biological flotation reagent because of its fast growth,easy availability,strong adaptability and environmental friendliness.Based on this,this paper firstly uses yeast as collector to systematically study the effect of yeast on the flotation performance of cassiterite,calcite and quartz.The feasibility of yeast as cassiterite collector was discussed based on the experimental data of cassiterite,calcite and quartz floatation with collector SHA.Secondly,the effect of yeast on the recovery rate of cassiterite,calcite and quartz in SHA flotation was explored through the mixed flotation experiment of yeast and SHA.Finally,scanning electron microscopy,Zeta potential,FTIR,XPS and DLVO theoretical calculation were used to investigate the interaction mechanism between yeast and cassiterite,calcite and quartz and so on.The research results are of great value to the development of cassiterite flotation reagent and the mechanism of cassiterite flotation.The results of flotation experiment show that cassiterite and calcite can be effectively recovered with yeast as collector under the condition of proper amount of yeast.The flotation recovery of cassiterite with yeast as collector was slightly lower than that with SHA as collector,the flotation recovery of calcite with yeast as collector was slightly higher than that with SHA as collector,and the flotation recovery of quartz had little change under the two systems.Proper amount of yeast can improve the recovery of cassiterite and calcite in SHA flotation system,and reduce the recovery of quartz flotation,while excessive yeast can inhibit the recovery of cassiterite in SHA flotation system.Scanning electron microscopy results showed that a large number of fine cassiterite with smaller particle size than yeast adhered to the surface of yeast,and a small number of yeast unevenly distributed on the surface of large cassiterite,calcite and quartz.Infrared spectroscopy and XPS analysis showed that chemisorption occurred between yeast and cassiterite,and C-O and C-OH on the surface of yeast were the active sites of chemisorption,while no or weak chemisorption occurred between yeast and calcite and quartz.DLVO analysis showed that fine cassiterite tended to coagulate with coarse cassiterite,and yeast cells tended to disperse.When the distance between cassiterite particles and yeast cells is less than 0.8 nm,yeast cells and cassiterite particles attract each other,and the gravity increases sharply with the decrease of the distance between them;At 69.07 nm,yeast and cassiterite particles tended to condense.At3.7nm,cassiterite particles tended to disperse stably between yeast cells.