The vanadyl porphyrin concentrations were determined spectrophotometrically according to the intensities of the absorption band at 570 nm, using in the calculation an extinction coefficient of 2. 9 multiplied by (times) 10**4 liters/(mole multiplied by (times) cm). Electronic spectra were taken in a Specord spectrophotometer (chloroform solvent), the mass spectra in a Varian MAT-311 mass spectrometer with an ionizing electron energy of 70 eV and an admission system temperature of 250 degree C. The crude oil and the gasoil differed considerably in content of vanadyl porphyrins (0. 047 and 0. 006 mu mole/g, respectively).
ASJC Scopus subject areas
- Chemical Engineering(all)
- Energy Engineering and Power Technology
- Fuel Technology