Study Of Ultrasound Coupled Mechanical Agitation To Enlarge Selective Dissolution Of Spodumene

In this paper,the selective dissolution of spodumene surface is strengthened and the flotation efficiency is improved by introducing ultrasound on the basis of mechanical agitation.The surface appearance is analyzed by scanning electron microscope,and the mechanism is studied by inductively coupled plasma test,X-ray electron energy spectrum test and reagent adsorption capacity test.The main conclusions are as follows:(1)By comparing the condition experiments of mechanical agitation and ultrasound coupled mechanical agitation pretreatment of spodumene.The results show that ultrasound coupled mechanical agitation can enhance the selective dissolution efficiency of surface elements of spodumene with coarse grain size(-0.15+0.038mm).The recovery of spodumene can be increased from about 15%(without pretreatment)to about 90%,while the maximum recovery of spodumene can only reach about 50% with mechanical agitation pretreatment.For fine spodumene(-0.038mm),there is no significant difference in the effect of ultrasound coupled mechanical agitation and mechanical agitation pretreatments on the flotation recovery of spodumene,both the recovery increases from about 40% to about 70%.Compared with mechanical agitation pretreatment,ultrasound coupled mechanical agitation pretreatment can achie Ve higher flotation recovery of coarse spodumene in shorter pretreatment time,lower dosage of sodium hydroxide and lower mechanical agitation speed.(2)The effects of ultrasonic parameters on the flotation recovery of spodumene,feldspar and quartz with different particle sizes are investigated.The results show that ultrasound coupled mechanical agitation pretreatment can enhance the selective separation of spodumene from gangue minerals such as feldspar and quartz.The ultrasonic parameter tests show that the increase of ultrasonic power(from 0W to100W),the decrease of ultrasonic frequency(from 105 KHz to 45KHz)and the increase of ultrasonic time(from 0min to 25min)all help to improve the flotation recovery of spodumene.The change of ultrasonic parameters has no obvious effect on the flotation recovery of feldspar and quartz.The results show that the optimal ultrasonic parameters for flotation separation of spodumene are as follows: ultrasonic power is 60 W,ultrasonic frequency is 45 KHz and ultrasonic time is 15 min.(3)Mechanism analysis shows that mechanical agitation and ultrasound coupled mechanical agitation pretreatment can improve flotation recovery by promoting selective dissolution of spodumene surface,,but ultrasounnd coupled with mechanical agitation can achie Ve higher selective dissolution efficiency by increasing the selective dissolution area(the quantity of selective dissolution)of spodumene mineral surface.Selective dissolution of spodumene exposes more Al and Li sites on the mineral surface,which helps to adsorb the collector sodium oleate,thus improving the flotation recovery of spodumene.