2-Dimensional and 3-Dimensional Zeolite Systems for Catalytic Cracking Made, Analyzed and Tested

In this PhD thesis, the knowledge of industrially relevant Fluid Catalytic Cracking (FCC) materials has been expanded, with a focus on their physicochemical properties and catalytic performance. Particular attention has been paid to the formation of carbon-rich deposits (coke) and the local composition within individual FCC particles. In addition, the limitations of conventional analytical techniques for FCC particles have been identified, and a new synthesis method has been developed for two-dimensional (2D) FCC materials, enabling more detailed characterization. Chapter 1 provides background on the FCC process and its role in the transition toward more sustainable feedstocks, such as biomass and plastic waste. It emphasizes the importance of a fundamental understanding of acid sites and reaction mechanisms for the rational design of FCC catalysts. Chapter 2 investigates coke formation on FCC particles as a function of reaction time and exposure to hexane. Using thermogravimetric analysis (TGA), confocal fluorescence microscopy (CFM), and Raman spectroscopy, it is demonstrated that coke formation increases with reaction time and that FCC particles are intrinsically heterogeneous. In situ measurements confirm these trends and reveal variations in coke formation and graphitization. Additional X-ray holotomography provides insight into the spatial distribution of coke, while also highlighting the complexity and heterogeneity of individual particles. Chapter 3 focuses on determining the local composition of FCC particles using CFM in combination with fluorescence labeling. Although zeolite and clay domains can be identified, light scattering and diffusion limitations—particularly in the presence of silica—restrict the resolution and depth of analysis. This underscores the need for alternative model systems. In Chapter 4, a new synthesis route for 2D FCC materials via spin coating is presented. These materials contain controlled ratios of zeolite, clay, and binder components and exhibit accessible Brønsted acid sites and porosity. Their planar morphology enables detailed investigation of zeolite–binder interactions, which is challenging in conventional FCC particles. Chapter 5 demonstrates the applicability of these 2D FCC materials as model catalysts for plastic pyrolysis. In situ microscopy shows that the presence of zeolite promotes the formation of larger aromatic products at lower temperatures. The developed 2D FCC materials offer new opportunities for fundamental insight into structure–property relationships and zeolite–binder interactions. In summary, this work contributes to a better understanding of FCC catalyst systems, which is essential for the development of more efficient and sustainable catalytic processes involving increasingly complex feedstocks, such as large polymer molecules or biomass rich in heteroatoms.