the sector as a key player in future carbon economies.
CO
CO
CO
Enhanced oil recovery (EOR) EOR is commercially mature. In this process, captured CO₂ is injected into depleted oil reservoirs to increase pressure and improve the mobility of crude oil, thereby extending field productivity. Several patents detail advanced cyclic injection methods that optimise recovery efficiency (Yee, 2018; Nazarian & Ringrose, 2014) . While EOR has a decades-long track record in North America and elsewhere, it remains a paradoxical solution: it allows significant volumes of CO₂ to be stored underground, yet simultaneously prolongs fossil fuel use. This duality continues to spark debate on whether EOR should be considered a bridge technology or a genuine contributor to long- term decarbonisation. Agriculture and food CO₂ has long been applied in the agriculture and food industries in relatively small but important volumes. In greenhouses, CO₂ enrichment enhances photosynthesis, leading to faster crop growth and higher yields. Similarly, CO₂ is indispensable in the beverage sector for carbonation, providing the characteristic fizz in soft drinks and sparkling water. While these markets are limited in scale compared to industrial applications, they illustrate the diverse roles of CO₂ as a resource. directly. It is widely applied as a refrigerant, a fire suppressant in safety systems, and as a solvent or working fluid in chemical processes. These applications, although modest in terms of global CO₂ demand, also reinforce the narrative that captured carbon is not merely a waste to be stored, but a versatile resource for multiple sectors. Industrial applications A range of industrial processes use CO₂ Turning CO₂ into fuels, chemicals, plastics, and products The most transformative utilisation pathways involve the conversion of CO₂ into fuels and chemicals, broadly classified into four categories: physical, chemical, biological, and
OIL
Mineralisation in building materials
Enhanced oil recovery
Food and agriculture
Figure 2 Direct uses of captured carbon
mineralisation (Godin, et al., 2021), (Fu, et al., 2022), (Kamkeng, et al., 2021) . At present, only a limited number of industrial chemicals are derived from CO₂, as the thermodynamic stability and kinetic inertia of CO₂ molecules result in harsh reaction conditions and low conversion efficiencies (Liu, et al., 2023) . Synthetic fuels Catalytic hydrogenation of captured carbon can be used to synthesise fuels and chemicals such as methane, methanol, formic acid, and dimethyl ether (DME) (Godin, et al., 2021) . Methanol and DME offer significant potential as versatile energy carriers and chemical intermediates. These products provide dual benefits, displacing fossil-based feedstocks while offsetting the costs of carbon capture and conversion. Catalyst developments aim to reduce the activation energy and enable efficient chemical conversion under milder conditions. Moreover, integrating renewable hydrogen into these processes provides a unique opportunity to link the utilisation of CO₂ with the broader decarbonisation of the energy system. Sustainable aviation fuels (SAF) combine CO₂ with renewable hydrogen, offering one of the approved pathways for decarbonisation of aviation fuels. Unlike conventional fossil fuels, ‘green fuels’ produced via CO₂ hydrogenation do not generate additional CO₂ emissions after use (Spadaro, et al., 2021) . The reverse water-gas shift (RWGS) reaction, where CO₂ is first reduced to CO and then hydrogenated, is an important chemical synthesis process. Otto et al. evaluated 123 such reactions and identified six chemicals – methanol,
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