ABSTRACT
I n some m e t h o d s of ana lys i s , e g X - r a y f luorescence spec t rometry , preconcent ra ted samples are r equ i r ed i n the s o l i d no t the aqueous phase. In such m e t h o d s the m e t a l i o n or ions to be d e t e r m i n e d are reacted w i t h a sui table o rgan ic che la t ing agent u n d e r appropr i a t e c o n d i t i o n s to p r o d u c e an i n s o l u b l e complex . The s m a l l a m o u n t of prec ip i ta te thereby ob ta ined f r o m a large v o l u m e of w a t e r s ample m i g h t then be left to 'age ' p r i o r to a carefu l f i l t ra t ion u n d e r con t ro l l ed cond i t i ons a n d d r i e d . The s o l i d t he reby o b t a i n e d is s u i t a b l e fo r me ta l s a n a l y s i s b y X - r a y f luorescence spec t romet ry of the s o l i d , o r after d i s s o l u t i o n i n a sui table reagent b y l i q u i d m e t h o d s s u c h as a tomic absorp t ion spectrometry.
