文山铝土矿Al_2O_3测试中半二甲酚橙的作用

THE FUNCTION OF SEMI-XYLENOL ORANGE IN THE TESTING OF AL_2O_3 OF BAUXITE IN WENSHAN

一水硬铝石及含刚玉(Al2O3)铝土矿的测试较困难。NaF置换滴定法以二甲酚橙及半二甲酚橙较敏锐。可用半二甲酚橙(变色酸度在PH=5～6)直接调节酸度,再用作滴定的指示剂,效果较好。

The testing of diasporite and bauxite bearing corundite is difficult. The xylenol orange and Semi - xylenol orange are sensitive in the NaF replacement titration method. We can use the semi -xylenol orange （color changing acidity PH5 -6） to adjust directly the acidity, and then to be the titration indicator.