KazNU Scientists Create Catalyst- and Hydrogen-Free Method for Producing Motor Fuel

As reserves of light and heavy crude oil decline, the need to find alternative pathways for producing motor fuels is growing. Petroleum refining residues (fuel oil, tar) resemble heavy, highly viscous crude oils, whose extraction volumes remain low, while processing them through conventional technological schemes is often unprofitable. At the same time, oil shale is typically high in ash content, which significantly complicates its independent processing and calls for integrated solutions.

Oil shale differs from other solid fossil fuels in its elevated hydrogen content within the organic matter (kerogen), with an H/C ratio reaching up to 1.7 (compared to 1.9 for oil and 0.4-0.5 for coal), which accounts for high yields of gaseous and liquid products during thermal processing. However, its high ash content complicates processing. Co-processing oil shale with heavy petroleum products through thermal-catalytic methods therefore represents a promising pathway for producing motor fuels and chemical products.

To study the co-pyrolysis of oil shale from the Kenderlyk deposit and heavy petroleum residual fractions in order to develop efficient technologies and rational pathways for converting raw materials into motor fuel components and specialty products.

The project will, for the first time, develop the physicochemical foundations for creating functional materials from a mixture of heavy petroleum products and Kenderlyk oil shale. The catalytic activity of natural polymetallic bauxite ores containing nickel-iron and titanium-iron compounds will be studied for the first time, enabling more than 90% conversion of the shale's organic mass while removing nitrogen and sulfur from liquid products. The effectiveness of applying ultrasound to a mixture of fuel oil and tar with oil shale will be determined for the first time, increasing the yield of light distillates. Based on the data obtained, a conceptual technological scheme for producing gasoline and low-sulfur diesel fuel via thermal cracking will be developed.

The project comprises five tasks: developing effective catalysts and conditions for thermal-catalytic hydrogenation of Kenderlyk shale; establishing a criterion for producing combined liquid fuel and chemical products through co-thermal decomposition of fuel oil and tar with shale; compiling a material balance for the co-thermal decomposition of mechanically activated shale and fuel oil; identifying trends in the chemical composition of distillate fractions under ultrasound influence; and developing a conceptual technological scheme for producing environmentally safe gasoline and diesel fuel components.

Pyrolysis is conducted in a Fischer retort in accordance with GOST 3168-93 (500°C, 30 minutes). Mechanical activation of shale samples is performed using an AGO-2 activator, and thermal decomposition takes place in a 14 cm³ microautoclave at 350°C. Chemical composition is determined using a "Khromatek" gas-liquid chromatograph, elemental composition with an EMA-502 microanalyzer, and IR spectra with a "Tensor II" spectrometer. Ultrasonic treatment is performed using a UZDN-2T disperser (frequency 22 kHz, power 150 W). Mathematical data processing is carried out using the Maple 13 software package.

Amid tightening environmental requirements for feedstock quality and growing demand for motor fuels in CIS countries and abroad, active research is underway to improve co-thermochemical processing of heavy petroleum residues with shale. The project's results will be published in journals ranked Q1 in Web of Science or with a CiteScore percentile of at least 80 in Scopus, strengthening Kazakhstan's scientific and technological standing in this field.

The developed technology requires no expensive catalysts or hydrogen, operates at relatively low pressure (3-5 MPa), and achieves 40-50% desulfurization of liquid products. Using local raw materials will reduce Kazakhstan's regional dependence on imported petroleum products, cut transportation costs, and create new jobs in the country's oil- and shale-producing regions.

At least 1 article in a Q1 Web of Science journal or with a CiteScore percentile of at least 80 in Scopus; at least 1 invention patent; at least 1 article in a journal recommended by KOKSON (or alternatively, 2 articles in Q1-Q2 journals or with a CiteScore percentile of at least 65, plus 2 articles in KOKSON-listed journals).

Spanning 36 months (2025-2027), the project will raise the technology readiness level from 2 to 4 and generate new knowledge at the intersection of organic chemistry, petrochemistry, and coal chemistry. It will expand Kazakhstan's raw material base for motor fuel production and strengthen the international standing of domestic science in this field.