Integrated CO₂ capture and reduction catalysis: Role of γ-Al₂O₃ support, unique state of potassium and synergy with copper

Carbon dioxide capture and reduction (CCR) process emerges as an efficient catalytic strategy for CO₂ capture and conversion to valuable chemicals. K-promoted Cu/Al₂O₃ catalysts exhibited promising CO₂ capture efficiency and highly selective conversion to syngas (CO + H₂). The dynamic...

Micro-kinetics analysis based on partial reaction networks to compare catalysts performances for methane dry reforming reaction

Designing a simple, yet representative reaction network for subsequent micro-kinetic analysis is important for limiting the cost of evaluation and ensuring model solvability. This is currently achieved by employing sensitivity analysis over a comprehensive reaction network (CRN) to screen reaction species. However, as a reaction network is...

Enabling complete conversion of CH₄ and CO₂ in dynamic coke-mediated dry reforming (DC-DRM) on Ni catalysts

Dynamic coke-mediated dry reforming of methane (DC-DRM) is an unsteady-state strategy to overcome the limitations of co-feed operation, including the fast deactivation of the catalysts and the loss of valuable H₂ in the reverse water gas-shift reaction. This paper proves the feasibility of DC-DRM on Ni-based catalytic systems,...

Impact of Promoter Addition on the Regeneration of Ni/Al₂O₃ Dry Reforming Catalysts

Industrial-scale reforming of methane is typically carried out with an excess of oxidant to suppress coking of the catalyst. On the other hand, many academic studies on dry reforming employ a CO₂/CH₄ ratio of unity to quickly observe coking which can be reduced by adding a catalyst promoter. In this work, Ni/Al<sub>2<...

Silica-Supported PdGa Nanoparticles: Metal Synergy for Highly Active and Selective CO₂-to-CH₃OH Hydrogenation

The direct conversion of CO₂to CH₃OH represents an appealing strategy for the mitigation of anthropogenic CO₂emissions. Here, we report that small, narrowly distributed alloyed PdGa nanoparticles, prepared via surface organometallic chemistry from silica-supported Ga^IIIisolated sites, selectively...

Challenges for the utilization of methane as a chemical feedstock

The abundance of methane has led to a strong interest to use methane as a feedstock in the chemical industry. One of the main challenges is the initial activation of the methane molecule. This has resulted in the development of several different approaches to utilize methane, some more developed than others. In this work the current status of...

Dry reforming of methane to test passivation stability of Ni/ Al₂O₃ catalysts

Catalyst passivation refers to the formation of a protective oxide layer on the active metal particles that prevents their oxidation when exposed to air. Common passivation procedures, when applied to Ni/ Al2O3 catalysts, typically result in a significant decrease of the overall Ni surface area and, accordingly, the catalytic activity....

Syngas production via microwave-assisted dry reforming of methane

Energy-efficient CH4-CO2 valorization to fuels and chemicals presents an urgent need considering the great variety of methane sources and the removal of greenhouse gases. In the present work, the microwave-assisted dry reforming of methane, DRM, has been carried out in a custom-designed rectangular mono-mode microwave applicator over several...

Spatial, temporal and quantitative assessment of catalyst leaching in continuous flow

Catalyst leaching is a major impediment to the development of commercially-viable processes conducted in a liquid-phase. To date, there is no reliable technique that can accurately identify the extent and dynamics of the leaching process in a quantitative manner. In this work, a tandem flow-reactor system has been developed, which allowed us...

The Nature and Catalytic Function of Cation Sites in Zeolites: a Computational Perspective

Zeolites have a broad spectrum of applications as robust microporous catalysts for various chemical transformations. The reactivity of zeolite catalysts can be tailored by introducing heteroatoms either into the framework or at the extraframework positions that gives rise to the formation of versatile Brønsted acid, Lewis acid and redox...

Multiscale Structure-Performance Relationships in Supported Palladium Catalysis for Multiphase Hydrogenations

The performance of heterogeneous catalysts in multiphase reactions in general is governed by different types of extrinsic and intrinsic structural effects on all length scales, i.e., on the macro- (m to cm), meso- (mm to µm), and microlevel (nm). This PhD research, with a catalysis-engineering approach, focused on several of these multiscale...