FORENSIC INVESTIGATION OF PETROLEUM COMPONENTS OF MIXED MOTOR GASOLINES

The main types of petroleum components that are used in the manufacture of mixed motor gasolines are considered. For the manufacture of mixed motor gasolines, a low-octane base is used, to which high-octane components are added. In many cases, reformate (catalytic reforming gasoline) and isopentane (isopentane fraction) are used as high-octane components of mixed motor gasolines. Straight-run gasoline and stable gasoline are often used as the low-octane gasoline base of blended automobile gasolines. Reformate is a liquid mixture of aromatic and saturated hydrocarbons used as a high-octane component of automobile (aviation) gasolines and raw materials in the production of aromatic hydrocarbons (arenas). The reformate is obtained by catalytic reforming of straight-run gasoline fractions. Isopentane (2-methylbutane (CH3)2CHCH2CH3) is a colorless, flammable liquid. The technical product is a mixture of isomeric pentanes and boils within 24 - 34°C. The isopentane fraction can be isolated from gas gasoline, from gasoline direct distillation of oil and gasoline catalytic cracking. Straight-run gasoline (nefras) is obtained from the processing of crude oil or gas condensate, oil shale or coal, natural gas or oil and gas. Straight run gasoline contains light gasoline fractions of direct distillation of oil with a boiling range of 35 - 180°C. Gas gasoline (gas stable gasoline) is obtained from natural and petroleum gases containing vapors of gasoline hydrocarbons. To separate them, the gases are compressed and cooled (compression method) or absorbed with oil or activated carbon. Gas gasoline is similar in chemical composition to straight-run gasoline, but contains lighter hydrocarbon fractions. The article discusses the results of a study of the listed petroleum components of mixed gasoline by gas-liquid chromatography. This method allows you to establish the qualitative and quantitative composition of mixed motor gasolines and their components. It is shown that from readily available petroleum components (isopentane fraction, aromatic hydrocarbons and gas stable gasoline) without the use of sophisticated technological equipment, a gasoline mixture with high detonation resistance, which is falsified automobile gasoline, can be obtained by mixing method. When mixed in certain proportions of reformate, isopentane fraction and gas stable gasoline, it is possible to obtain marketable gasoline that will meet the requirements of regulatory documents for gasoline. The considered technology allows, when mixing commodity gasolines A-92 (A-95) with reformate, isopentane fraction and gasoline gas stable in the calculated proportions, to improve the operational characteristics (detonation resistance) of the obtained gasoline mixture or to increase the volume of the obtained gasoline mixture without improving its performance.

Cobalt hybrid catalysts in Fischer-Tropsch synthesis

Currently, cobalt and zeolites are used in Fischer-Tropsch synthesis (FTS) to produce gasoline-range hydrocarbons (GRHs) that constitute clean and environmentally friendly fuels. This technology has earned a great deal of attention from researchers across the world, as it provides a substitute for fuel derived from fossil crudes, which have hitherto been the sole source of the petrol and diesel required by the industry. However, owing to the depletion of the earth’s oil and coal reserves and the unfavourable environmental impact of conventional fuel production, an alternative source of fuel is needed. This article provides a critical review of the technological challenges involved in producing middle isoparaffins and olefins (gasoline hydrocarbons) by FTS. These involve combining cobalt-based catalysts and zeolites to form hybrid catalysts. In this review, we address most of these by setting out each method of creating cobalt and zeolite hybrid catalysts in turn, so that researchers can identify which applications are most effective for producing GRHs.

ADAPTATION OF THE METHOD OF CHROMATOGRAPHIC ANALYSIS OF GASOLINE TO ACHIEVE PURPOSES OF GEOCHEMICAL PROSPECTING FOR OIL AND GAS

Geochemical survey is commonly applied during geological exploration to predict petroleum potential of large areas and to estimate the content of traps identified by the results of seismic survey. C1-C6 hydrocarbon concentrations in samples of surface and subsurface air, soil, snow, water, etc. are used as predictive indicators. At the exploration stage the capabilities of geochemical methods can be significantly expanded by comparing the content of gasoline hydrocarbons in samples of formation fluids and in samples of near-surface sediments. The method of chromatographic analysis of gasolines Chromatec Gazolin has been adapted for sample analysis. The taken measures to increase the sensitivity allowed us to register individual hydrocarbons C1-C10 in concentrations up to 0,01 ppb, which is obviously lower than their background content in the oil prospect areas. The revealed patterns are used in the geological interpretation of geochemical distributions based on theoretical ideas about the subvertical migration of hydrocarbons from the reservoir to the surface.