Abstract
Trace metals in crude oil and their products are commonly determined by atomic absorption spectrophotometry. The presence of some metals (e.g., Ni, Cu, Fe, As) in the crude oil causes poisoning of the catalysts used in refining processes, and other metals (e.g., V) cause corrosion problems, thus reducing the efficiency of the refining plant [1-3]. On the other hand, the nature and level of metals in the oil can be used for identification of the source of the oil. The presence of copper in refined products promotes formation of gums and lacquers during heating or storage and thus accelerates the deterioration of these products and reduces the storage stability [4]. Vanadium concentration above 2 ppm in fuel oils can lead to severe corrosion of turbine blades and deterioration of refractory furnace linings and stacks.....