Recent applications of high-performance liquid chromatography to the analysis of metal complexes.

Determination of copper, iron and vanadium in petroleum by direct sampling electrothermal atomic absorption spectrometry

Determination of sulfur and deleterious trace elements in crude oil has long been an area of active investigation and still attracting interest due to their undesirable economic consequences and adverse environmental impacts. Therefore, analytical methods devoted to their sensitive, rapid, and accurate determination are of paramount importance in various areas of oil refining and petrochemical industry. In the present review, occurrence and implications of the main metallic constituents in crude oil are summarized. Furthermore, currently available methodological approaches including sample pretreatment procedures along with the most commonly used measurement techniques employed for crude oil analysis are overviewed. A summary of the applications and recent developments over the past years is discussed. The basic principle, pros and cons of each analytical method are highlighted. The overview is based on 172 references.

Critical Review on the Analytical Methods for the Determination of Sulfur and Trace Elements in Crude Oil.

Exploratory data analysis using API gravity and V and Ni contents to determine the origins of crude oil samples from petroleum fields in the Espírito Santo Basin (Brazil)

In this research article, spectrophotometric method for the determination of iron with 1,10-phenanthroline (phen) in two different crude oil samples from different oil fields in the Suez-Gulf region of Egypt has been proposed. The method is efficient, reliable and inexpensive where a cost-effective technique, along with commercially available spectrophotometric reagent, was utilized in this work. The method was based on decomposition of the organic matrix by combustion in a heating muffle furnace at 550°C. The inorganic residue was then dissolved in diluted nitric acid and the iron was reduced to the divalent state. The color was developed by the addition of 1,10-phenanthroline as chelating agent after adjusting the pH of the solution, then the absorbance of the solution was measured at approximately 510 nm after a short reaction period. The limit of detection (LOD) and limit of quantification (LOQ) obtained were found to be 0.017 and 0.051 μg/mL, respectively. The effect of interferences was studied and the accuracy of the method was evaluated by recovery experiment, analysis of oil reference material and by comparison of results with those obtained using flame atomic absorption spectrometer (FAAS) after dilution in an organic solvent for sample preparation.

Simple Spectrophotometric Method for Determination of Iron in Crude Oil

A method has been developed for the simultaneous formation and solvent extraction of cobalt (II), copper (II), iron (II) and vanadium (IV) complexes of bis (acetylpivalylmethane)ethylenediamine (H2APM2en) in methyl isobutyl ketone. The complexes are eluted from a reversed phase HPLC column with a mixture of methanol:water:acetonitrile and detection was at 260 nm. The method has been applied to the simultaneous determination of cobalt, copper, iron and vanadium in crude petroleum oils at the ng level.

K. P. Mahar

Papers

Simultaneous determination of cobalt, copper, iron and vanadium in crude petroleum oils by HPLC