用双膦酸分离胶磷矿和白云石

Separation for Phosphate and Dolomite with Diphosphate

哈里蒙德管浮选试验表明,双膦酸W-10对胶磷矿强烈抑制而对白云石抑制很弱,表现出良好的选择性。混合矿的分选表明在pH为6时获得相同的分选效率,双膦酸的浓度只需磷酸的1/200。即使在中性及碱性介质中,也有很好的分选效果。由双膦酸的逐级解离常数可知,在pH为5～7时,它能与Ca^(2+)以六元环螯合而使磷矿物受强烈抑制。在pH为9时,作用的机制与磷酸在pH为6时相似。

Hallimond tube flotation shows that diphosphonic acid W -10 depresses phosphate strongly, bat has almost no effect on dolomite. The mixtion of phosphate and dolomite indicates that to obtain same separation efficiency at pH 6, only 1 / 200 concentration of phosphoric acid is required for W-10 used as depressant, It also works well even in neutral and alkaline mediums. It may be know from dissociation constants of W-10 that W-10 can chelate Ca2+ to form a hexabasic ring at pH 5~ 7 however, its mechanism of depression at pH 9 is similar to that of phosphoric acid at pH 6,