Study On Application Of A New Cationic Collector In Flotation Of Magnesite Ore

Magnesite is an advantageous mineral resource in China,mainly distributed in Anhai-Dashiqiao area of Liaoning Province.However,due to the excessive exploitation of rich ores for a long time,a large number of medium and low-grade magnesites have been abandoned and left unused,which has brought certain environmental pressure to the local area.Flotation is widely applied to the separation and purification of low-grade mineral resources.The traditional collector,DDA(Dodecylamine)is not only difficult to continue to meet the declining grade of raw ore,but also has its own shortcomings such as low water solubility,low selectivity,and difficult processing of foam products.At present,according to the report there are a lot of modified cationic collectors on the market,but most of them are on the high side,which is not reasonable economically.Therefore,the research and development of new cationic collectors for the above shortcomings has always been a hot spot in the field of flotation research.In order to improve the shortcomings of DDA,a new type of cationic collector was developed in this project,which was used for reverse flotation purification of magnesite.Through the flotation test of quartz,dolomite and magnesite,a new collector LS55 was researched.The main components of LS55 are some tertiary amine and quaternary ammonium salt.The flotation effect of LS55 is compared with that of DDA.Under the condition of p H 5-7,the flotation rates of quartz,dolomite and magnesite are 95%,52%and 41%respectively when LS55 is used as collector,and 91%,85%and 78%respectively when DDA is used as collector.In the tests of artificial mixed minerals,the concentrate with Si O₂content of 0.28%and recovery of 57.2%was obtained by using LS55 as collector,and all indexes were better than DDA.The analysis results show that the main impurities of a magnesite ore in Haicheng are quartz and dolomite.Through the three times reverse flotation tests of a magnesite ore in Haicheng,the flotation indexes of 46.77%Mg O,0.18%Si O₂,0.66%Cao and 63.9%recovery were obtained under the experimental conditions of 130g/t DDA,150g/t sodium hexametaphosphate and 1500g/t sodium silicate;Under the experimental conditions of LS55 dosage of 125g/t,p H value of 6-7,sodium hexametaphosphate dosage of 150g/t and sodium silicate dosage of 1500g/t,the best concentrate indexes of concentrate with Mg O content of 46.85%,Si O₂content of 0.16%,Ca O content of 0.57%and recovery of 72.3%,all the indexes were better than DDA.According to the solution chemical and infrared spectrum analysis,the adsorption forms of LS55 and regulator on quartz surface are physical adsorption;the adsorption forms on dolomite surface are physical adsorption and chemical adsorption;the adsorption forms on magnesite surface are physical adsorption and chemical adsorption.According to group electronegativity calculation,HLB calculation and contact angle measurement,it is shown that the collecting ability of LS55 for quartz is stronger than that of DDA,while that of dolomite and magnesite is weaker than that of DDA.Three phase foam test and defoaming mechanism analysis showed that the larger the section of polar group of the same kind of agent,the more brittle the foam was,the easier it was to burst.The order of defoaming was quaternary ammonium salt>tertiary amine>DDA.The research of this subject provides tests basis for the efficient utilization of low-grade magnesite resources.