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This thesis expands the toolbox available to catalysis researchers regarding novel catalyst support materials and provides ways to optimize the textural and electronic properties of established ones, unlocking unconventional product distributions previously inaccessible in the process. The findings herein seek to unravel general ways supports influence catalyst reactivity, but they should be of particular use to those working with alumina catalyst supports and those that apply them in Co-catalyzed conversions of synthesis gas (CO+H2) to value-added chemicals. It is revealed how applying a novel synthesis route of the α-polymorph allows the synthesis of Al2O3-materials that exhibit ample surface area needed for the synthesis of supported metal catalysts, much like industrially applied ϒ-Al2O3 provides, but overcoming the hydrothermal frailty of the latter. As a proof-of-concept, Co nanoparticles (NPs) are dispersed on the high-surface-area α-Al2O3 and the resulting catalyst is applied for Fischer-Tropsch synthesis (FTS), an ideal model system demanding multiple-year catalyst lifetimes under constant exposure to a hydrothermal reaction environment established by the reaction byproduct (H2O) steam. A theoretical basis for the superior hydrothermal stability of α-Al2O3 over its ϒ-counterpart is established from surface modeling methods, pointing to a lack of AlT surface sites on α-Al2O3 to rationalize this beneficial property. In Fischer-Tropsch synthesis applications targeting high-value olefins, FeCx-based catalysts are mostly incompatible with hydrogen-rich syngas feeds due to the active phase’s activity for the water-gas shift reaction (WGSR), creating the need for catalysts that can produce olefins without co-production of CO2 formed during the WGSR. FTS catalysts based on Co are traditionally unfit for this application, as they commonly deplete primary product α-olefins through their high hydrogenation capacity. To tackle this problem, the role of pore architecture and oxide promoters on olefin selectivity are systematically addressed on a series of Co-based catalysts on ϒ-Al2O3 support materials of increasingly open pore structure, applying Lewis-basic alkali- and lanthanide promoters of different kinds and loadings. A strategy optimizing both properties results in catalysts capable of producing C5+ hydrocarbons with over >70 C% selectivity (α = 0.75), with high-value α-olefins and some linear alcohols making up to 67 C% of the lighter hydrocarbon (C5-10) condensates with minimal CO2 side-production (<1 C%). An optimized α-olefin selective catalyst designed with this knowledge is then integrated with a molecular reductive hydroformylation (RHF) catalyst in slurry-phase operation for the one-step conversion of hydrogen-rich syngas (CO/H2 = 2). Preferentially linear n-alcohols that are the result of this tandem integration are complemented by strictly linear n-alcohols originating from CO-insertion chain termination of the FTS mechanism. This way, the product mixture is enriched with >50 wt% in C2+ alcohols – of which ~84% are terminal alcohols – at CO conversion levels >70% with negligible CO2 side-production. Over 80 C% of alcohol products generated by this tandem of catalysts are longer chain higher alcohols of 4 to 13 carbon atoms, making the developed process attractive for the one-pot conversion of syngas to valuable precursors of a wide range of plasticizers.
