Methanol

Technology

What is it?

Methanol is conventionally synthesised at large scale from synthesis gas (or syngas), a mixture of hydrogen and carbon monoxide typically at an H₂/CO ratio of 1.8 ~ 2.2, derived through steam reforming of natural gas or steam gasification of coal. Renewable methanol can also be synthesised from syngas derived from a renewable source such as biomass or direct hydrogenation of CO₂. Methanol can be converted back into hydrogen when needed or utilised directly in a number of applications.

Why is it important?

Methanol can be stored and transported in liquid form at ambient temperatures. It can be converted to yield high purity hydrogen or utilised directly in a number of applications in the energy and chemical sectors.

Characteristics

• Volumetric hydrogen density: 100kgH₂/m³ at ambient conditions
• Gravimetric hydrogen density: 12.5% by mass
• Storage conditions: Liquid at ambient conditions

Benefits

• Greater volumetric energy density than hydrogen gas
• In CO₂ hydrogenation method - Makes use of CO₂ as a feedstock. This can be sourced from waste streams or direct air capture
• Can leverage existing methanol handling and transport infrastructure
• Liquid under ambient conditions
• Flexibility in its production, storage, transport and end uses. It can be dissociated to yield high purity hydrogen or used directly as a fuel for methanol fuel cells, conventional liquid transport fuel for internal combustion engines and as an intermediate for chemical manufacturing and other purposes

Limitations

• Poisonous to humans, requires similar precautions as petrol and diesel
• If converted back into hydrogen, releases CO₂
• Note: The TRL for this technology varies based on the synthesis method. Conventional synthesis from syngas has a TRL of 9. Direct hydrogenation of CO₂ has a TRL of 6-7.  Integrated biomass pyrolysis with methanol synthesis has a TRL of 3. Photocatalytic conversion of CO₂ and water into methanol has a TRL of 2-4.  Methanol produced via solid oxide electrolysis has a TRL of 1

RD&D priorities

• Improve methanol synthesis via hydrogenation of CO₂ with hydrogen (this method is less mature than the incumbent syngas conversion process)
• Develop catalysts and test
• Process intensification and miniaturisation of conventional methanol synthesis to match distributed nature of renewable biomass resources
• Improve energy efficient extraction of hydrogen from methanol after transport

Known active organisations

• CSIRO
• The University of Adelaide
• The University of Melbourne
• The University of New South Wales
• The University of Sydney
• The University of Western Australia