HIGH-TEMPERATURE GAS-CHROMATOGRAPHY - ATOMIC-EMISSION DETECTION OF METALLOPORPHYRINS IN CRUDE OILS

High temperature gas chromatography-atomic emission spectroscopy is us ed for the detection of vanadyl, nickel, and iron porphyrins in crude oils. The operational Variables are investigated with regard to the ef fects on performance in high temperature GC-AED. Under optimal conditi ons, the method provides charactersitic metal distributions for oils f rom different sources. The method is also advantageous in the study of decomposition of petroleum metal species. Several crude oils were ana lyzed for the content of the distillable metals in comparison with tot al metals as determined by a direct spectroscopic method.