通过热力学计算、X线光电子能谱及红外光谱测试,研究pH对油酸钠在钛铁矿与钛辉石表面吸附的影响。研究结果表明:钛铁矿在pH〉5.5时都保持了较好的可浮性,钛辉石在pH为6~9和pH〉10的条件下具有一定的可浮性;在酸性条件下,钛铁矿表面的Fe3+,Ca2+,Mg2+和Ti4+以及钛辉石表面的Fe3+,Ca2+,Mg2+和Al3+均能与油酸钠发生化学作用,其中钛铁矿表面的Fe2+在浮选过程中可以被氧化为Fe3+,成为矿物表面主要的活性吸附点,继而油酸根离子取代羟基生成油酸铁而吸附于矿物表面;钛辉石表面则以Ca2+和Mg2+与油酸根的化学作用为主。在碱性条件下,钛铁矿与钛辉石表面均主要以Ca2+和Mg2+为主与油酸钠作用。
The influence of pH on adsorption of sodium oleate on the surface of ilmenite and titanaugite was studied by means of thermodynamics calculation,infrared spectrum and X-ray photoelectron spectroscopy analysis.The results show that ilmenite displays good floatability when pH5.5,and titanaugite possesses certain floatability when pH is 6?9 and pH10.Under acidic condition,ions of Fe3+,Ca2+,Mg2+ and Ti4+ on ilmenite surface and ions of Fe3+,Ca2+,Mg2+ and Al3+ on titanaugite surface are able to chemically react with sodium oleate.Fe3+ derived from the oxidation of Fe2+ on ilmenite surface during the flotation process becomes the major activated adsorption site,which results in the adsorption of the iron oleate coming from the replacement of hydroxyl group by oleate ion on the surface of ilmenite.For titanaugite,however,the chemical reaction between Ca2+,Mg2+ and oleate ion is the main mechanism.On the other hand,on alkali condition,oleate reacts mainly with Ca2+and Mg2+ on both of ilmenite and titanaugite.