Detection of selenium in environmental samples, inorganic mixtures, and a specific method for its gravemetric analysis

Abstract
A novel compound, i.c. malonyl dihydrazide (MDH) was synthesized by coupling of diethylmalonate and hydrazine hydrate in alcoholic medium. The reagent is applied for the field test detection of Se, and garvimetric analysis of Se and Te in various real samples, i.e. sediment, waste-water, cigarette paper, cabbage, etc. A drop of sample containing more than 2 and 6 g of Se on test-tube/plate and test-paper were found to be detected, respectively. The reagent is successfully applied for the detection of Se and Te in semi-micro analysis of inorganic mixtures containing different ions. The gravimetric determination of Se and Te is highly selective, as the analysis conditions are different for both the elements. The non-stick precipitates also having good filtration characteristics, therefore 5 mg Se or Te present in the solution can be estimated accurately. Almost an metal ions associated with real samples did not interfere. The detection and determination with the proposed reagent is simple, rapid, selective and sensitive in comparison to other conventional methods. The data of estimation of Se and Te in standard samples prove the reliability of the proposed gravimetric determination.