Direct Crude Oil-to-Chemical Conversion through Steam Catalytic Cracking: Recent Advances in Catalytic Formulation, Reactor Strategies, and Industrial Prospects

A promising technology emerging in modern refining is the direct conversion of crude oil to chemicals. It aims to reduce the traditional processing chain of actual refineries by minimizing fuel production while maximizing yields of higher value petrochemicals such as light olefin and aromatic. The inherent molecular complexity and processing difficulty of crude oil require continuous innovation to drive this technology toward industrial feasibility. Recent efforts focus on steam catalytic cracking (SCC) as a particularly attractive route due to its capacity to suppress coke formation and enhance selectivity toward the production of light olefins. This review provides a comprehensive analysis of recent developments in direct SCC of crude oil. Cracking mechanisms are discussed showing the role of steam and its impact on directing the cracking pathways toward β-scission over protolytic cracking. Kinetics is thoroughly studied comparing traditional lumped models and more advanced molecular-level models. Advances in catalytic formulations are presented showing that acidity and porosity modifications of ZSM-5 are necessary to meet crude oil SCC requirements. Reactor configurations and their operational factors are evaluated, including the next-generation design of multi-zone fluidized-bed (MZFB) reactor that integrates reaction, vaporization and regeneration in the same vessel. Finally, techno-economic considerations showed that higher capital costs of SCC reactor systems are due to requirements for solids handling, heat integration, and advanced reactor control systems. Existing challenges such as the high-temperature requirements and steam generation associated with SCC remain important contributors to CO₂ emissions, emphasizing the need for efficient energy management strategies.