DETERMINATION OF GERMANIUM BY AAS IN CHLORIDE-CONTAINING MATRICES

Interference effects of NaCl on the ET-AAS determination of Ge have be en studied. The use of several matrix modifiers to alleviate this prob lem such as Ni and Zn perchlorates and nitrates, nitric acid, ammonium nitrate are reported. The stabilizing effect of Zn and Ni perchlorate s allows the use of high pretreatment temperatures. NaCl is thus therm ally volatilized from the atomizer by employing pretreatment temperatu res higher than 1500 degrees C resulting in an improved sensitivity. G ermanium levels in zinc plant slag samples, have been determined and c ompared to those obtained for the same samples spiked with NaCl with p latform and wall atomization using nickel perchlorate as a matrix modi fier. The results were compared with those from a hydride generation s ystem equipped with a liquid nitrogen trap. The recoveries for germani um have been almost complete and amount to 99% for the original slag s amples and 80% for 15% (w/w) NaCl containing spiked samples.