Simultaneous determination of Cr, Fe, Ni and V in crude oil by emulsion sampling graphite furnace atomic absorption spectrometry

摘要: In this work a simple and reliable method for the simultaneous determination of Cr, Fe, Ni V in crude oil, using emulsion sampling graphite furnace atomic absorption spectrometry is proposed. Under best conditions, sample masses around 50 mg were weighed polypropylene tubes emulsified mixture 0.5% (v v−1) hexane + 6% (m Triton X-100®. Considering compromised pyrolysis an atomization temperatures 1400 °C 2500 °C, respectively. Aliquots 20 μL reference solution co-injected into tube with 10 1.0 g L−1Mg(NO3)2 as chemical modifier. The detection limits (n = 10, 3σ) characteristic were, respectively: 0.07 μg g−1 19 pg Cr; 2.15 31 Fe; 1.25 44 Ni; 1.15 149 V. reliability proposed was checked by fuel oil Standard Reference Material (SRMTriton X-100®1634c – NIST) analysis. concentrations found presented no statistical differences compared to certified values at 95% confidence level.