烷基硫酸盐捕收剂对菱镁矿和白云石的浮选性能研究

Flotation Performance of Alkyl Sulfate Collector for Magnesite and Dolomite

白云石是低品质菱镁矿中主要的含钙杂质,但是白云石与菱镁矿的晶体结构相似、组成相近,导致钙镁矿物浮选分离困难。开发新型高效脱钙捕收剂是提高白云石与菱镁矿分离效率的主要手段。基于此,探索性地将十二烷基硫酸钠(SDS)作为白云石的捕收剂进行钙镁分离,考察了矿浆pH值、SDS浓度以及可溶性离子Ca^(2+)、Mg^(2+)和Fe^(3+)对菱镁矿与白云石浮选性能的影响,结果表明:在SDS浓度为20×10^(-5)mol/L、矿浆pH值为10时,白云石与菱镁矿有较好的浮选分离效果。Ca^(2+)和Mg^(2+)对菱镁矿与白云石均有抑制作用,对两种矿的浮选性差异影响较小。Fe^(3+)对白云石的抑制作用较小,对菱镁矿的抑制作用较大,有利于两种矿的浮选分离。FTIR与Zeta电位结果表明,SDS在白云石表面的吸附量远远大于在菱镁矿表面的吸附量,且Fe^(3+)可以促进SDS在白云石表面的吸附,抑制SDS在菱镁矿表面的吸附,从而增大白云石与菱镁矿间的可浮性差异。

Dolomite is the main calcium-containing impurity of low quality magnesite ore.However,the similar crystal structure and composition resulted in the difficult flotation separation of dolomite and magnesite.Developing novel and efficient collectors is the main means to improve the separation efficiency of magnesite and dolomite.Based on this,sodium dodecyl sulfate(SDS)was used as the collector of dolomite.The effects of slurry pH value,collector concentration and soluble ions of Ca^(2+),Mg^(2+)and Fe^(3+)on the flotation performance of magnesite and dolomite were investigated.The results showed that a better flotation separation result was obtained when the SDS concentration was 20×10^(−5) mol/L and pulp was 10.The ions of Ca^(2+)and Mg^(2+)could simultaneously inhibit the flotation of magnesite and dolomite,which had little effect on the flotation difference of the two minerals.The inhibitory of Fe^(3+)on dolomite was weaker than that of magnesite,which was conducive to the flotation separation.The FTIR and Zeta potential results indicated that the adsorption capacity of SDS on the dolomite surface was much greater than that on the magnesite surface,and Fe^(3+)could promote the SDS adsorption on the dolomite surface and inhibit the SDS adsorption on the magnesite surface,thus increasing the flotation difference between dolomite and magnesite.