Methanol is a critical platform chemical and an increasingly important energy carrier. While global production is currently dominated by fossil-based pathways primarily natural gas (average 65%) and coal (average 35%), there is however an urgent industrial mandate to decarbonize the supply chain. This review provides a rigorous quantitative evaluation of conventional and emerging carbonaceous feedstocks, including biomass, agricultural residues, municipal solid waste, and captured carbon dioxide (CO2). Quantitative analysis reveals that while traditional biogas offers methane concentrations averaging 50–80%, emerging substrates can also provide superior methane yields. A significant contribution of this work is the integration of the latest 2025 findings on semolina processing waste, which demonstrates a high-hydrogen (H2) potential (average 23.0% H2) for bio-methanol synthesis.
Reddy et al. (Sun,) studied this question.