Development of a method to determine Ni and Cd in biodiesel by graphite furnace atomic absorption spectrometry.

Resumo
This paper proposes a low cost, simple, fast method for determining Ni and Cd in biodiesel samples by graphitefurnaceatomicabsorptionspectrometry (GFAAS). The method was evaluated in biodiesel from different sources. Tungsten was used as a permanent modifier and the samples were prepared in the form of microemulsions, by mixing about 0.5 g of biodiesel with 5 g of surfactant (Triton X-100) in volumetric flasks and completing the volume with HNO3 1% (v/v). The detection limits obtained for Ni and Cd in microemulsions were ≤0.9 and 0.1 μg L−1, respectively. The relative standard deviation (% R.S.D., n = 12) was ≤8.20% for Ni (washed animal fat sample) and ≤4.71% for Cd (sunflower oil sample). Accuracy was checked based on addition and recovery experiments, which yielded recovery rates varying from 93% to 108% for Ni and from 98% to 116% for Cd. Sample preparation is rapid and easy, and the use of an inorganic standard for calibration makes this sample preparation procedure suitable for routine applications.
Descrição
Palavras-chave
Biodiesel, Absorptionspectrometry, Microemulsions, Metals
Citação
LOBO, F. A. et al. Development of a method to determine Ni and Cd in biodiesel by graphite furnace atomic absorption spectrometry. Fuel, v. 90, n. 1, p. 142-146, jan. 2011. Disponível em: <https://www.sciencedirect.com/science/article/pii/S0016236110004801>. Acesso em: 29 nov. 2012.