巯基类小分子有机抑制剂对复杂硫化矿物浮选行为的抑制机理

Depression mechanism of small molecular mercapto organic depressants on flotation behavior of complex sulfides

通过浮选实验、红外光谱测定，考察了脆硫锑铅矿、磁黄铁矿和铁闪锌矿在丁黄药作用下的浮选行为和巯基类小分子有机抑制剂（巯基乙酸、巯基乙醇）对三种矿物的抑制效果以及Cu^2＋离子对巯基化合物抑制效果的影响。结果表明：用丁黄药作捕收剂，脆硫锑铅矿和磁黄铁矿在pH2～10范围内都有良好的可浮性，铁闪锌矿在酸性条件下可浮性好，三者分离困难；在pH6～8之间，采用巯基乙酸和巯基乙醇作抑制剂，脆硫锑铅矿与磁黄铁矿和铁闪锌矿的分离是可能的；但铜离子存在时，3种矿物之间的选择性分离是难以实现的。红外光谱测试表明：在抑制剂分子中有多种官能团如-SH、-COOH、-OH等。丁黄药和抑制剂在矿物表面存在竞争吸附，有机抑制剂携带亲水基团，使得矿物表面更容易亲水，从而受到抑制。

With butyl xanthate as a collecter, the flotation behavior of jamesonite, pyrrhotite and marmatite, the depressing effects of small mercapto organic depressant （mercaptoacetic acid, mercaptoethanol ） and the effect of Cu^2＋ ion on depressing ability of mercapto compound were studied through flotation test and infrared spectrum. The results show that jamesonite and pyrrhotite have good floatability in the pH range of 2 - 10 and marmatite has good floatability in the acid and it is difficult to separate these minerals. In the pH range of 6 -8, the separation of jamesonite and pyrrhotite, marmatite is possible when using mercaptoacetic acid and mercaptoethanol as depressants. In case of the presence of Cu^2＋ ion, however, it is difficult to separate the three minerals. Infrared spectrum demonstrates that there are a number of function groups such as -SH, -COOH, -OH in the molecular structure of depressant. Xanthate and depressant compete in their adsorption on surface of sulfide minerals. Organic depressant has hydrophilic functions groups （-COOH, -OH, ） to make the surfaces of pyrrhotite and marmatite more hydrophilic, resulting in the depression of the minerals.