生物表面活性剂对原矿中稀土淋洗效果的影响

Leaching effect of bio-surfactants on rare earth elements in raw ores

为实现我国南方离子型稀土矿的无铵浸析,以生物表面活性剂-皂角苷为浸矿剂,通过淋洗实验探讨了皂角苷浓度、溶液p H、原矿粒径、固液比对稀土淋洗效果的影响,结果表明:在原矿粒径为0.25 mm,皂角苷浓度50 g/L、p H=5.5和固液比(g/m L,下同)1∶15条件下,振荡24 h后,皂角苷对稀土的淋洗效率可达76.78%.而在柱淋洗实验中,累积淋洗效率为43.16%,仅不到硫酸铵的1/2;原因在于皂角苷对稀土的淋洗效率会受溶液和原矿的性质、流速等因素的影响,导致淋洗反应迟缓,拖尾期长.

The effects of saponin concentration, solution p H value, particle size and solid-liquid ratio on the leaching efficiency of rare earth ores were investigated in leaching experiment by using saponin, a bio-surfactant, in order to realize the non-ammonium leaching of the ion-type rare earth ores in South China. The results showed that the leaching efficiency of saponin to rare earth reached 76.78 % after they were oscillated for 24 hours when the concentration of saponin was 50 g/L, p H of solution was 5.5 and solid solution ratio was1∶15（g/ml, similarly hereinafter）. In addition, the cumulative washing efficiency of column leaching by using saponin reached 43.16 %, which was less than 1/2 of that by using ammonium sulfate. The reason was that the leaching efficiency of saponin to rare earth ores was affected by the properties of the solution and raw ores,velocity and other factors, leading to the low reaction and long tail period.