Structured catalysts designed and manufactured by 3D-printing technique for functional integration of catalytic systems

Microporous zeolites are widely used as heterogeneous catalysts in a wide variety of chemical and petrochemical industries to produce value-added chemicals and fuels, owing to their large surface area, acid-base properties, high thermal stability, and excellent shape-selectivity. The overall goal of this research was to shape engineer composite zeolites and fine-tune their physiochemical properties to improve the catalytic production of dimethyl ether (DME) and light olefins that are typically used as substitution to diesel fuel and polymer precursors, respectively. Specifically, HZSM-5 and silicalite-1 zeolites were formulated into monolithic contactors using 3D printing technique, followed by subsequent SAPO-34 crystals growth through a secondary hydrothermal method to produce zeolite composites of core-shell structure with controlled micro-meso-macro-porosity. Furthermore, the 3D-printed ZSM-5 monoliths were doped with various metals such as Cr, Ga, Cu, Y, Mo, and Zn to control their surface acidity, and used as heterogeneous catalysts in light olefins and DME production through methanol dehydration reaction. Analysis of catalytic performance revealed enhancement in products yield and improvement in catalyst stability. Due to the synergistic integration of surface acidity and hierarchical porosity, high yield of light olefins (70%) and DME (80%), and excellent anti-coking stability were demonstrated”--Abstract, page iv