Use of emulsion systems for the determination of sulfur, nickel and vanadium in heavy crude oil samples by inductively coupled plasma atomic emission spectrometry

Abstract

A useful and rapid procedure is described for the determination of sulfur, nickel and vanadium in crude oil by inductively coupled plasma atomic emission spectrometry. Samples were prepared by emulsifying crude oil in water. Aqueous inorganic solutions with the same amount of emulsifier and solvent were used as calibration standards. Heavy crude oils were analysed and the results were compared with those obtained by digestion methods. To evaluate the accuracy of the method, National Institute of Standards and Technology Standard Reference Materials, 1622c Sulfur in Residual Fuel Oil and 1634a Trace Elements in Fuel Oil, were analysed. No statistically significant differences were observed between the results obtained by this method and the certified values. The precision of the method was in the range from 1 to 3% relative standard deviation.