The results of research in the radiation processing of synthetic oil derived from oil– bitumen rockof the Balakhany deposit in Azerbaijan are presented. The study has been conducted on a 60Co gamma_source at a dose rate of P = 0.5 Gy/s and various absorbed doses of D = 43–216 kGy. Samples of synthetic oil from natural bitumen rocks have been analyzed by chromatography, gas chromatography–mass spectrometry, and IR -spectroscopy, and their radiation resistance has been evaluated. The results of the study allow for bothassessment of the feasibility of manufacturing petrochemicals for various applications by radiation processing and use of these materials for isolating radioactive sources to preclude their impact on the environment. Oil–bitumen rock (OBR) is a natural material formed from crude oil in the upper layers of the Earth crust as a result of the slow evaporation of light fractions from the oil, natural oil deasphalting, and the processes of interaction of its components with oxygen and sulfur. According to UN estimates, the world’s geological reserves of OBR amount to ~360 billion tons on the hydrocarbon (HC) basis and are an alternative source of HC feedstock. The object of investigation was the synthetic oil derived from OBR of the Balakhany field of Azerbaijan. Experiments were carried out on an MRKh γ-30 60Co gamma-ray source at a dose rate of 0.5 Gy/s. By distillation in a Retort Heating Jacket apparatus at a temperature of 950 F (510°C), 50 mL of synthetic crude was obtained from 375 g. The rock composition (%) was as follows: oil 22, water 6, sand 72. Samples of synthetic oil were irradiated to different absorbed doses in the range of 43–216 kGy in air or vacuum to follow the kinetics of the processes and to reveal the role of oxygen in the radiation resistance of the OBR.The samples of the synthetic oil intended for chromatographic analysis were dried with anhydrous sodium sulfate (Na2SO4) and diluted with dichloromethane (СН2Cl2); mass chromatograms in the m/z range of 35–400 (m/z is the ion mass to charge ratio) were recorded on a GCMS Trace DSQ instrument (Thermo Electron, Finnigan USA, 2005); and components of the samples were identified by the spectra. The sample notation was as follows: 12169, the initial synthetic oil; 12170, the synthetic oil irradiated for 96 h in air; and 12171, the synthetic oil irradiated for 96 h in a vacuum. IR spectra of the samples were recorded on an M-80 spectrophotometer in the wave number range of 700–4000 cm–1. The gaseous products were analyzed by gas chromatography. The relatively high radiation resistance of the synthetic oil, recovered from the OBR, in vacuum and air below 50°C is associated with the presence of paraffins, polynuclear aromatic hydrocarbons, and resin asphaltene substances in its composition. This makes it possible to use the synthetic oil as a feedstock for manufacturing a waterproof material applicable in radiation fields, including the disposal of radioactive waste. The organic matter of the OBR may serve as a promising source material for manufacturing various fuels, lubricating oils, coke, and asphalt. Hydrogen, hydrocarbon gases, and olefin hydrocarbons can be produced from the synthetic oil by the joint ionizing radiation and heat treatment at consistent values of the temperature and the dose rate.
|