磷矿中三氧化二铝的测定一般均按部颁标准进行。部颁标准中Ⅰ法,虽有一定的准确度,但要经过两次分离,手续繁琐,过程冗长。为了缩短分析过程,寻求更加快速、准确的方法,我们曾设想不分离,用加入掩蔽剂的方法直接用EDTA进行络合滴定但因磷矿中干扰元素比较复杂而未能获得成功 Phosphate rock in the determination of aluminum oxide are generally ministerial standards. The ministerial standard Ⅰ method, although a certain degree of accuracy, but to go through two separate procedures cumbersome, lengthy process. In order to shorten the analysis process and to find a faster and more accurate method, we have envisaged no direct sequestration with complexing titration with addition of masking agents but failed to achieve success due to the complex interference elements in phosphate rock