اندازه گیری فلزات نادر خاکی بوسیه کمپلکسومتری

a simple, sensitive and selective method for solvent extraction and spectrophotemetric determination of lanthanum (ii) europium (iii), and cerium (iii) is described , the rare earth metals are extracted into chloroform solution of n-phenylbenzohydroxamic acid (pbha) at ph 9-10 various parameters are studied to optimize the extraction conditions. the molar absorptivity is found to increase from 6x10 to 9,4 x10 1.mol. cm with the increase in atomic number of the rare earths.