十二胺对石英和高岭石的分级浮选试验研究

Experimental Study on Fractional Flotation of Quartz and Kaolinite by Dodecylamine

通过理论计算及试验验证的方法,研究了十二胺对不同粒级高岭石和石英的分级分选特性。结果表明,DDA对高岭石和石英的浮选回收率均随着粒度减小而增大,DDA药剂浓度为1.5×10mol/L时,在弱碱环境中分选高岭石和石英效果较好;石英表面氧原子和高岭石(001)面羟基氧原子是药剂和矿物发生吸附作用的主要吸附位点,+250μm粒级高岭石表面羟基氧原子位点暴露不足是其脱附严重的主要原因;石英对DDA具备优先吸附性,DDA在分选高岭石-石英混合矿物时,各粒级精矿品味随着粒度减小而减小,精矿产率随着粒度减小而增大,250-125μm粒级的分选效率最高,为78.47%;DDA对500-125μm高岭石-石英混合矿物体系具有良好的分选效果,而对于-125μm混合矿物体系难以实现高品质分选。

Through theoretical calculation and experimental verification,the separation characteristics of dodecylamine for kaolinite and quartz with different particle sizes were studied.The results show that the flotation recovery of kaolinite and quartz by DDA increases with the decrease of particle size,and the concentration of DDA is 1.5×10mol/L,kaolinite and quartz can be separated well in weak alkaline environment.The oxygen atom on the surface of quartz and the hydroxyl oxygen atom on the(001)surface of kaolinite are the main adsorption sites for the adsorption of reagents and minerals.The insufficient exposure of the hydroxyl oxygen atom on the surface of+250μm kaolinite is the main reason for its serious desorption,quartz has preferential adsorption to DDA.When DDA is used to separate kaolinite quartz mixed minerals,the concentrate grade of each particle size decreases with the decrease of particle size,and the concentrate yield increases with the decrease of particle size.The separation efficiency of 250-125μm particle size is the highest,which is 78.47%.DDA has good separation effect for 500-125μm kaolinite quartz mixed mineral system,but it is difficult to achieve high-quality separation for-125μm mixed mineral system.