Acid-Tailored β-Zeolite with Lewis-Acid Dominance for Selective Oxidation of Furfural to Succinic Acid: from Catalyst Design to Process Integration

The selective oxidation of furfural to succinic acid represents a promising route for producing biobased polymer precursors. This work develops an efficient and stable H2SO4-modified β-zeolite catalyst for succinic acid production. Systematic screening revealed that treatment with 0.25 M H2SO4 for 60 min yielded the optimal catalyst (β-H2SO4-60), achieving 99% furfural conversion and 75.1% succinic acid selectivity. Comprehensive characterization indicates that controlled acid treatment induced selective surface dealumination, transforming framework aluminum into extra-framework species. This process generates a high density of Lewis acid sites while maintaining a low Brønsted-to-Lewis acid ratio, which is conducive to the formation of succinic acid. Through a three-step purification process comprising rotary evaporation, dichloromethane extraction, and ethanol recrystallization, succinic acid powder with a high purity of 99.5% was successfully obtained. Coupled with a techno-economic analysis that confirms the economic viability of the biobased succinic acid production route, this work provides a holistic strategy from catalyst design to process integration for the sustainable production of biobased succinic acid.