Normal and second derivative spectrophotometric determination of niobium using solid phase extraction technique
Autor: | Mostafa M. Hamed, Refat F. Aglan, S. A. El-Reefy |
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Rok vydání: | 2015 |
Předmět: | |
Zdroj: | Journal of Analytical Chemistry. 70:1103-1110 |
ISSN: | 1608-3199 1061-9348 |
DOI: | 10.1134/s1061934815090075 |
Popis: | This paper describes a rapid method for niobium preconcentration, separation and determination by using solid phase extraction (SPE). The activity level of 94Nb is still very low in the environment. However, on account of its long half life, 94Nb would be one of the important isotopes in the near future for the safe management of radioactive waste. SPE method using freshly precipitated microcrystalline naphthalene as an adsorbent has been developed to separate and preconcentrate trace amount of niobium from aqueous samples for the detection by normal and second derivative spectrophotometry. The influence of some analytical parameters on the quantitative recoveries of the Nb(V) was investigated by batch technique. The complex extracted on naphthalene has an absorption maximum at 380 nm. The optimum pH range for the sorption is 7–8. The molar absorptivity is 1.40 × 104 L/(mol cm), the sensitivity being 0.0066 µg/cm2 of niobium. Derivative spectrophotometry in conjunction with extractive pre-concentration of Nb(V) with SPE is used for determining Nb(V) at concentration levels down to 25 ppb in initial sample. The foreign ions interference has been studied and the optimized conditions developed were utilized successfully for the trace determination of niobium in alloy steel, environmental and wastewater samples. |
Databáze: | OpenAIRE |
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