Assessing the potential of an integrated bio-/e-methanol production pathway from Saudi date palm fruit and its residues using process modelling, techno-economic analysis and life-cycle assessment

The Middle East faces a dual challenge of decarbonising transport while creating value from underutilised agricultural residues. In Saudi Arabia, the date palm ( Phoenix dactylifera L .) sector generates large quantities of downgraded fruit and lignocellulosic waste that are often discarded or openly burned. However, the integrated conversion of these streams with biogenic CO 2 recovery for methanol production remains insufficiently assessed. This study therefore assesses the technical, environmental, and economic performance of an integrated date-palm-based bio-/e-methanol pathway under Saudi Arabian conditions. The proposed biorefinery combines (i) fermentation of low-grade dried dates to ethanol with recovery of biogenic CO 2 , (ii) gasification of date palm waste (DPW) to syngas followed by bio-methanol synthesis, and (iii) hydrogenation of captured biogenic CO 2 using electrolytic H 2 to produce e-methanol. The novelty lies in integrating these complementary biochemical, thermochemical, and CO 2 -utilization pathways within a common process, environmental, and economic assessment framework. An Aspen Plus V12 model was coupled with well-to-tank life-cycle assessment and techno-economic analysis to evaluate process performance, environmental impacts, and economic viability. The integrated pathway enables high-purity bio-/e-methanol production while improving the utilization of biogenic carbon. Renewable electricity reduces GWP100 from 19.77 to 13.43 g CO 2 -eq/MJ, while the techno-economic assessment demonstrates strong economies of scale, with cost parity projected at approximately 28.5 kt/yr and investment break-even at approximately 47.9 kt/yr. Overall, the results identify electricity carbon intensity and production scale as key determinants of the environmental and economic viability of integrated date-palm-based bio-/e-methanol production.