Electrocatalytic transformation of carbon dioxide (CO2) and water into chemical feedstocks offers the potential to reduce carbon emissions by shifting the chemical industry away from fossil fuel dependence. We provide a technoeconomic and carbon emission analysis of possible products, offering targets that would need to be met for economically compelling industrial implementation to be achieved. We also provide a comparison of the projected costs and CO2 emissions across electrocatalytic, biocatalytic, and fossil fuel-derived production of chemical feedstocks. We find that for electrosynthesis to become competitive with fossil fuel-derived feedstocks, electrical-to-chemical conversion efficiencies need to reach at least 60%, and renewable electricity prices need to fall below 4 cents per kilowatt-hour. We discuss the possibility of combining electro- and biocatalytic processes, using sequential upgrading of CO2 as a representative case. We describe the technical challenges and economic barriers to marketable electrosynthesized chemicals.

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What would it take for renewably powered electrosynthesis to displace petrochemical processes

The separation of ethane from its analogous ethylene is of great importance in the petrochemical industry, but very challenging and energy intensive. Adsorptive separation using C2H6-selective porous materials can directly produce high-purity C2H4 in a single operation but suffers from poor selectivity. Here, we report an approach to boost the separation of C2H6 over C2H4, involving the control of pore structures in two isoreticular ultramicroporous metal–organic framework (MOF) materials with weakly polar pore surface for strengthened binding affinity toward C2H6 over C2H4. Under ambient conditions, the prototypical compound shows a very small uptake difference and selectivity for C2H6/C2H4, whereas its smaller-pore isoreticular analogue exhibits a quite large uptake ratio of 237% (60.0/25.3 cm3 cm–3), remarkably increasing the C2H6/C2H4 selectivity. Neutron powder diffraction studies clearly reveal that the latter material shows self-adaptive sorption behavior for C2H6, which enables it to continuously ...

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Boosting Ethane/Ethylene Separation within Isoreticular Ultramicroporous Metal–Organic Frameworks

The chemistry of chemical recycling of solid plastic waste via pyrolysis and gasification: State-of-the-art, challenges, and future directions

The environmental and societal consequences of the increasing levels of carbon dioxide in our atmosphere are among the most significant challenges society currently faces. Carbon dioxide utilizatio...

Opportunities and Challenges for Catalysis in Carbon Dioxide Utilization

Steam cracking is a well-established commercial technology for ethylene production. Despite decades of optimization efforts, the process is, nevertheless, highly energy and carbon intensive. This r...

Recent Advances in Intensified Ethylene Production—A Review

New Trends in Olefin Production

The role of mass and heat transfer in the design of novel reactors for oxidative coupling of methane

The process intensification possibilities of a gas–solid vortex reactor have been studied for biomass fast pyrolysis using a combination of experiments (particle image velocimetry) and non-reactive and reactive three-dimensional computational fluid dynamics simulations. High centrifugal forces (greater than 30g) are obtainable, which allows for much higher slip velocities (>5 m s–1) and more intense heat and mass transfer between phases, which could result in higher selectivities of, for example, bio-oil production. Additionally, the dense yet fluid nature of the bed allows for a relatively small pressure drop across the bed (∼104 Pa). For the reactive simulations, bio-oil yields of up to 70 wt % are achieved, which is higher than reported in conventional fluidized beds across the literature. Convective heat transfer coefficients between gas and solid in the range of 600–700 W m–2 K–1 are observed, significantly higher than those obtained in competitive reactor technologies. This is partly explained by re...

Computational Fluid Dynamics-Assisted Process Intensification Study for Biomass Fast Pyrolysis in a Gas–Solid Vortex Reactor

Using detailed kinetic models in computational fluid dynamics (CFD) simulations is extremely challenging because of the large number of species that need to be considered and the stiffness of the associated set of differential equations. The high computational cost associated with using a detailed kinetic network in CFD simulations is why one-dimensional simulations are still used, although this leads to substantial differences compared to reference three-dimensional simulations. Therefore, a methodology was developed that allows one to use detailed single-event microkinetic models in CFD simulations by on the fly application of the pseudo-steady-state assumption to the radical reaction intermediates. Depending on the reaction model size, a speedup factor of more than 50 was obtained compared to the standard ANSYS Fluent routines without losing accuracy. As proof of concept, propane steam cracking in a conventional bare reactor and a helicoidally finned reactor was simulated using a reaction model contain...

Laurien Vandewalle

Papers

New Trends in Olefin Production

The role of mass and heat transfer in the design of novel reactors for oxidative coupling of methane

Computational Fluid Dynamics-Assisted Process Intensification Study for Biomass Fast Pyrolysis in a Gas–Solid Vortex Reactor

Necessity and Feasibility of 3D Simulations of Steam Cracking Reactors

Dynamic simulation of fouling in steam cracking reactors using CFD