Extension and evaluation of screening technique for particulates
The rapid screening procedure technique for the analysis of six hazardous metals in oxide form: beryllium, cadmium, copper, lead, mercury and zinc developed by Bethea and Lin has been extended to include seven ferrous and non-ferrous cations in their oxide forms. It is suitable for field use in the metallurgical industry. The present procedure includes methods for determining the oxides of antimony, iron, chromium, nickel, vanadium, tin, and silver in addition to the six non-ferrous cations listed above. The qualitative procedures originally based on standard geochemical and quantitative analysis methods have been modified as necessary to conform to the anticipated lower detection limits required for screening particulate stack samples obtained as a result of emission or compliance testing and for qualitative analysis of oil shales.
Solubilization is achieved by digestion in demineralized, deionized water followed by acid solubilization in 0.5N nitric acid, then by selective solubilization of CuO, NiO , and V 0 in hot 3N nitric acid and the final solution of BeO, Feâ€ž0 , and Sb 0 in hot concentrated sulfuric acid. Subsequent cation separation was obtained by complex-forming extractions in suitable solvents at an appropriate pH. The reagents used include dithizone, dithiol, dimethvlgloxin-o diphenylcarbazide, diethyldithiocarbamate and bathophenanthroline. Interference free spot tests are used for the identification of the thirteen cations present.