CO - to - methanol process CO + 3H
CH OH + H O
Step 1
Step 2
Step 3
Step 4 Green methanol for use in fuels and chemicals
CO capture Many technologies can be used alongside CO captured from various sources , including air, industrial ue gases , and biogenic processes.
Methanol synthesis Reactors designed to carry out methanol synthesis in a loop can result in highly e cient, simple , and robust equipment suitable for exible plant operation. These reactors usually
Methanol distillation Carrying out methanol distillation in a three - column reactor o ers an enhanced low-risk solution that tailors downstream methanol purication to suit product grade and maximise O pex and C apex trade-o s.
Catalyst
feature a tube cooled converter (TCC) and catalyst columns. Tube cooled converter Typically used for feeds with high CO 2 content.
Tubes
CO
Inert balls
Gas in
Gas in
Gas out
Figure 1 CO2 -to-methanol process
outputs of diverse feedstock pathways to be deployed across transport and industry using established infrastructure. It can be stored, transported, and handled using established systems, including tankers, terminals, and bunkering infrastructure. In maritime transport, methanol is emerging as a practical alternative to conventional marine fuels. The shipping sector faces significant challenges in adopting low-carbon solutions due to long asset lifetimes and the scale of fuel demand. Methanol engines are already commercially available, enabling their use in both newbuild vessels and retrofit applications. This allows for incremental adoption while maintaining operational continuity. Methanol also offers advantages in handling compared to some alternative fuels. It is less toxic than ammonia and does not require storage under high pressure or cryogenic conditions, simplifying fuel management. While its lower energy density requires larger storage volumes, its compatibility with existing systems supports its use as a near-term solution for reducing emissions in shipping. In aviation, methanol can be used as a feedstock for sustainable aviation fuel through methanol-to-jet pathways. This enables the production of fuels that meet aviation specifications while incorporating renewable carbon and hydrogen inputs. Although indirect, this application highlights methanol’s role in supporting decarbonisation in sectors where direct electrification is not feasible. Within the chemical industry, methanol is
280°C. Under these conditions, the conversion of synthesis gas to methanol is limited per pass, requiring the use of a synthesis loop in which unreacted gases are recycled back into the reactor. This loop configuration is essential for achieving high overall conversion. A key parameter in this process is the recycle ratio, defined as the ratio of circulating gas to fresh feed. This parameter directly influences feedstock utilisation and production cost, particularly in e-methanol systems where hydrogen is a significant cost component. Optimising the recycle ratio is therefore critical to achieving efficient and economically viable operation. In systems where syngas composition varies, maintaining an appropriate balance between hydrogen and carbon oxides is essential. A ratio close to (H₂ - CO2)/(CO + CO₂) ≈ 2 is typically required for efficient methanol synthesis. Hydrogen addition can be used to adjust this balance, increasing methanol yield and improving overall carbon utilisation. Methanol therefore provides a route to convert carbon from a range of sources into a usable fuel and chemical feedstock, while also enabling the utilisation of renewable electricity through hydrogen production. In doing so, it allows carbon, hydrogen, and renewable energy inputs to be integrated into a single, scalable product stream. Cross-sector integration and infrastructure compatibility As a liquid at ambient conditions, methanol provides a practical link between production systems and end-use sectors, enabling the
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