Elucidation of Reaction Pathways in the Succinic Acid–Gamma‐Butyrolactone Reaction System with Biomass‐Derivable Tetrahydrofuran Solvent

ABSTRACT Gamma‐butyrolactone (GBL) is an important industrial chemical, and the production of biomass‐derived GBL from succinic acid (SA) has gained attention in recent years. However, many previous studies on the SA–GBL reaction did not consider the environmental impacts and effects of solvent reactions. This study investigated the effects of biomass‐derivable tetrahydrofuran (THF) solvent on SA–GBL hydrogenation to achieve environmentally friendly GBL production. The experiments were conducted using the THF solvent, commercial Pd (5 wt%)/Al 2 O 3 catalyst, and H 2 gas (2.0 MPa at room temperature) at 230° C for 6 h. The reaction pathways in THF were experimentally elucidated and compared with those in conventional 1,4‐dioxane. The results revealed that THF promotes pathways involving three components: GBL, THF, and 1,4‐butanediol (BDO). Specifically, the reactions of THF to GBL and BDO, as well as the conversion of BDO to GBL, were enhanced. Furthermore, owing to the high miscibility of THF with water, THF promotes hydration (from succinic anhydride (SAN) to SA) and oxidation (from GBL to SAN and propionic acid). Overall, these results demonstrate that THF enhances the controllability of GBL consumption compared to 1,4‐dioxane.