Published June - July 2026, Pg. 69-75

Section: Young scientists and specialists

UOT: 665.644.4

DOI: 10.37474/0365-8554/2026-06-07-69-75

Chemical mechanisms of the catalytic cracking process and its role in the modern oil refining industry

G.S. Garashov - Azerbaijan State University of Oil and Industry

This paper presents a comprehensive study of the chemical mechanisms, technological features, and industrial significance of the catalytic cracking process in modern oil refining. The main objective is to systematically analyze the fundamental principles governing the conversion of heavy hydrocarbons into lighter, high-value products and to identify key factors influencing process efficiency.  
It is shown that the catalytic cracking process is primarily governed by carbocation reaction mechanisms occurring in the presence of acidic catalysts, particularly zeolites. Within this framework, high-molecular-weight hydrocarbons undergo a sequence of reactions including protonation, isomerization, β-scission, and hydrogen transfer, leading to the formation of gasoline fractions, olefins, and other light products. The overall mechanism proceeds through three main stages: formation of active carbocations, chain reactions, and final stabilization.  
Special attention is given to the role of zeolite catalysts, whose pore structure and acidity significantly influence product selectivity and yield. It is demonstrated that not only catalyst activity but also its structural characteristics are critical determinants of process performance. In addition, optimization of operating parameters such as temperature, pressure, contact time, and catalyst circulation enhances productivity while reducing energy consumption.  
The study also examines the principles of Fluid Catalytic Cracking (FCC) technology, including heat and mass transfer phenomena, product distribution, and energy balance considerations. Modern approaches involving digital technologies, such as artificial intelligence and big data analytics, are highlighted as effective tools for process optimization and real-time control.  
The results indicate that catalytic cracking should be regarded not merely as a chemical transformation process but as a complex, multi-factor, and highly controlled chemical-technological system. It plays a crucial role in the production of high-octane fuels and olefins, ensures efficient utilization of hydrocarbon resources, and contributes to emission reduction. The proposed integrated approach provides a scientific basis for future advancements, including the development of advanced catalysts, implementation of digital control systems, and adaptation to alternative feedstocks.

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