Sustainable Aviation Fuel Production via the Methanol Pathway: A Technical Review

Due to the compatibility towards today’s aviation infrastructure, sustainable aviation fuels (SAF) are expected to contribute to a significant reduction of this sector’s CO2 emissions. The methanol pathway represents a synthesis-based route for producing SAF that can utilize various feedstocks, including electrolytically produced H2 and atmospheric CO2 through a power-to-liquid (PtL) process, which can be implemented at large-scale. The process is considered advantageous compared to other routes, primarily in terms of yield and low levels of byproduct formation, and is projected to efficiently produce jet fuel (C8-C16). This review analyzes the state of science for the entire process chain consisting of methanol synthesis, methanol-to-olefin conversion, oligomerization, and hydrogenation. Here, special attention is drawn to the respective feedstocks, reaction systems, reactor design and process layouts to highlight technology-specific challenges to be considered. After individually reviewing the sub-processes, their interfaces are analyzed to derive research demands on the process side.