Comparison of thermal and catalytic cracking of fuel oil with addition of polyethylene waste and tire waste

Thermal and catalytic cracking play a key role in modern oil refining, enabling the efficient processing of raw materials to produce fuel products with high performance characteristics. These processes are aimed at breaking down high-molecular-weight hydrocarbons to form lighter compounds suitable for use as motor fuels. One of the directions for improving these technologies is the incorporation of secondary raw materials, such as polymer waste and used tires, which contributes both to solving environmental problems and increasing the economic efficiency of processing. The use of polyethylene and tire waste as modifying additives to fuel oil in the cracking process represents a promising research direction. The processing of polyethylene waste and tires by thermal cracking not only reduces the accumulation of these wastes but also yields valuable products such as gasoline and diesel fractions with high octane and cetane numbers. This also helps to reduce the burden on natural resources, decrease carbon-containing emissions, and promote the development of a circular economy. In this study, the processes of thermal and catalytic cracking of fuel oil containing 10 wt. % low-density polyethylene waste (LDPE) and 5.0 wt. % used tire crumb were investigated at a temperature of 450 oC and a feed rate of 1 h-¹. The catalytic cracking process was conducted using the celite-containing catalyst Zeocar-600. The catalytic cracking of the raw material mixture increased the yield of light fractions by 5.5 wt. % while simultaneously reducing the yield of the heavy gas oil fraction by 12.7 wt. %. After the hydrotreatment process, the gasoline and diesel fractions can be used as components of commercial automotive fuels. Thus, the application of polymer waste and used tires in the thermal and catalytic cracking of fuel oil is an effective method for resource conservation and reducing the environmental impact of the oil refining industry. The development of such technologies contributes to the creation of sustainable production chains and the formation of economically beneficial solutions within the framework of the circular economy concept. Moreover, such methods allow enterprises to comply with modern environmental standards, minimizing potential legal risks associated with waste disposal. Future research prospects include catalyst optimization, the search for new additives, and the study of the influence of various process parameters on product yield and quality.