manufacturing (Gandionco, et al., 2024) . While many of these processes are currently at the pilot scale, their potential to decarbonise the chemical industry is significant, particularly when coupled with renewable hydrogen and low-carbon electricity. Plastics derived from CO₂ also share the benefits of reducing emissions and generating economic value. A widely studied route involves reacting CO₂ with epoxides (oxiranes) to form cyclic carbonates, which are then polymerised into polycarbonates. Catalysts such as alkali metal halides and quaternary ammonium compounds enhance CO₂ polymerisation yield and selectivity. Song and colleagues demonstrated that CO₂-based polycarbonates had excellent thermal properties and biodegradability, supporting circular economy goals (Song, et al., 2022) . Non-isocyanate polyurethanes (NIPUs), produced from bis(cyclic carbonates) and diamines, offer eco-friendly alternatives to conventional plastics by reducing toxic intermediates and energy use. Recent reviews showcase diverse CO₂-based polymerisation strategies (CO₂/epoxide, CO₂/olefin, CO₂/alkyne, CO₂/isocyanide), yielding polymers with unique features such as controlled degradability and aggregation-induced emission. Despite rapid progress, significant barriers remain. CO₂ activation requires high energy input, limiting efficiency and scalability. While global plastics production exceeded 390 million tons in 2023, CO₂-derived plastics represented only a niche market. The industry faces regulatory gaps and demand uncertainty, even as it accounts for ~3.4% of global greenhouse gas emissions (CIEL, 2019) . Nevertheless, industrial players such as Covestro have commercialised CO₂-based polyols, and LanzaTech has scaled microbial fermentation routes, showing that market integration is feasible when coupled with supportive policy frameworks. Innovations in electrochemical reduction, microbial pathways, and novel catalysts will be critical to expand the role of carbon-derived plastics and chemicals in the low-carbon transition. Solid carbon products Unlike fuels or chemicals that re-emit CO₂ upon use, solid carbon products offer a pathway for
H H
H +
CO
Fuels
Chemicals & plastics
Formic acid, Dimethyl carbonate, Ethylene carbonate Cyclic carbonates, Polycarbonates
DME
Methanol
Ethylene, Propylene
SAF
Figure 3 Synthetic fuels
formaldehyde, formic acid, oxalic acid, urea, and dimethyl ether – with potential for significant CO₂ emissions reductions while offering economic viability (Otto, et al., 2015) . Five of these rely directly on CO₂ and H₂ as feedstocks, highlighting the need for renewable hydrogen in enabling large-scale deployment. These compounds also serve as building blocks for polymers, solvents, and other industrial applications. Chemicals and plastics The transformation of captured CO₂ into chemicals and plastics is among the most promising pathways for building a carbon- based circular economy. Such processes mitigate emissions while generating high- value products that substitute fossil-derived feedstocks in diverse industries. Urea, widely used in fertilisers, is produced by reacting CO₂ with ammonia. Methanol, synthesised from CO₂ and hydrogen, is a platform chemical with applications in fuels, solvents, and as a precursor for olefins and formaldehyde (Olah, et al., 2018) . More advanced catalytic routes convert CO₂ into formic acid, dimethyl carbonate, and ethylene carbonate, used as solvents, electrolytes in lithium-ion batteries, or intermediates in fine chemicals (Aresta, et al., 2013) . Recent advances in electrochemical CO₂ reduction have demonstrated the selective production of ethylene, propanol, and acetate using tailored catalysts, bringing new opportunities for electrified chemical
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