Porous Bimetallic Oxide Catalyst for CO2 Conversion

The patent employs a composite catalyst system combining metal oxide nanoparticles (Fe3O4, Co3O4, CuO, ZnO, ZrO2) supported on porous materials (alumina, silica, titania) with basic sites (alkali metal carbonates, hydroxides, or oxides). This composite structure enables both high activity for CO2 conversion and high selectivity for C4+ olefins through synergistic catalysis, achieving production capacity and selectivity that conventional single-material catalysts cannot achieve simultaneously.

The catalyst design incorporates spatially differentiated functions: metal oxide nanoparticles provide active sites for CO2 activation and conversion, while basic sites on the surface provide selective adsorption and activation of CO2 molecules. The porous support structure creates specific microenvironments with controlled pore sizes (0.5-2.0 μm) that favor the formation of longer-chain hydrocarbons. This local differentiation of catalytic properties throughout the catalyst structure enables simultaneous improvement of productivity and selectivity.

The patent operates the catalytic conversion process at relatively low temperatures (200-400°C) and pressures (1-10 atm), significantly lower than conventional fossil fuel refining processes. The unique catalyst composition with multiple metal oxides and basic sites enables high activity at these milder conditions, reducing energy expenditure while maintaining high productivity for hydrocarbon production from CO2.

The patent converts carbon dioxide, traditionally viewed as a waste product and harmful greenhouse gas, into valuable hydrocarbon products. By using CO2 as the carbon source instead of fossil fuels, the process eliminates the need for energy-intensive extraction and refining operations while producing the same useful hydrocarbons. This transforms a harmful substance into a beneficial feedstock, simultaneously reducing energy consumption and addressing climate change.

The catalyst structure employs a nested hierarchical architecture where metal oxide nanoparticles are dispersed within porous support materials with specific pore sizes (0.5-2.0 μm). This nested structure provides multiple confinement effects that favor chain growth reactions, enabling the formation of longer-chain hydrocarbons (C4+) through sequential addition reactions. The porous structure acts as a nanoreactor that concentrates reactants and stabilizes transition states for oligomerization and polymerization reactions.

The catalyst is segmented into distinct functional components: metal oxide nanoparticles (Fe3O4, Co3O4, CuO, ZnO, ZrO2) that provide active sites for CO2 activation, basic sites (alkali metal carbonates, hydroxides, or oxides) that selectively adsorb and activate CO2, and porous support structures (alumina, silica, titania) that provide surface area and pore confinement. This segmentation of functions within the catalyst enables optimized performance for producing larger chain hydrocarbons, with each component contributing specifically to chain growth and product selectivity.