Abstract
Vanadylporphyrin complexes are extracted from oils of the North Buzachi oil-and-gas-bearing region at 20°C with N,N-dimethylformamide (DMF) as an extractant, which exhibits a good ability to separate porphyrin complexes into fractions with increasing polarity. In the visible region, the electronic spectra of the metalloporphyrin concentrates isolated from the oil differ slightly and have two intense absorption bands at 573 and 534 nm (which correspond to vanadylporphyrin complexes) and one band at 550 nm (which is attributed to nickelporphyrins). According to the results of calculation by graphical extrapolation using the Beer–Lambert law, the content of nickelporphyrins in the extract is 11 times lower than that of vanadylporphyrins. The IR spectra of the porphyrinates show strong bending vibrations of –C–H– of pyrrole fragments at 809.27 and 3024.79 cm –1 , which also indicate the presence of vanadium(IV) porphyrinate in the isolated fraction.