High-Temperature methanolysis of cellulose: A method for efficient conversion of cellulose without hydrogen and without catalysts

This study presents a green high-temperature methanolysis strategy without exogenous hydrogen and catalysts, achieving efficient directional conversion of cellulose. Experimental results demonstrate complete cellulose conversion in the methanolysis system (360°C,1h), yielding liquid products dominated by α-methylglucoside (40.1 % selectivity) with minor esters, short-chain alcohols, and alkanes as byproducts, highlighting remarkable selectivity control. Comparative analysis with conventional pyrolysis reveals fundamental differences in product distribution and structural evolution mechanisms. Multidimensional characterization via gas chromatography-mass spectrometry (GC-MS) and comprehensive two-dimensional gas chromatography coupled with time-of-flight mass spectrometry (GC × GC-TOF-MS) confirms 77.9 % selectivity toward sugar derivatives in methanolysis products, characterized by α-glycosidic bonds that starkly contrast with levoglucosan-dominated dehydrated structures in pyrolysis oils. Multiscale characterization of solid residues (Fourier-transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy) further verifies that methanolysis selectively cleaves glycosidic bonds while preserving cellulose’s fibrous morphology and hydrogen-bonded network ordering, whereas pyrolysis residues exhibit disordered carbonized aggregates due to radical-mediated carbon skeleton reorganization. A kinetic model was established based on time-dependent cellulose conversion profiles. This work provides critical theoretical and technological foundations for the high-value, full-component utilization of cellulose resources.