Catalytic conversion of hemicellulosic sugars derived from biomass to levulinic acid

Catalytic conversion of hemicellulosic sugars from biomass towards levulinic acid production was conducted using modified-zeolite Y (commercial). The zeolite was treated by NaOH of different concentration (x M) before used for the conversion of C5 sugars to levulinic acid. The modified zeolites had a larger porosity and an increased concentration of stronger acid sites compared to the untreated zeolite. Levulinic acid yield of 4.6% (conversion of C5 sugar to levulinic acid: 42.7%) was maximized at 190 °C and reaction time of 180 min (batch reactor), when using the zeolite treated with 0.25 M NaOH. In addition, with the absence of C6 sugar, the conversion of C5 sugar was higher than that of C5-C6 sugar mixture. The present work provides a new heterogeneous catalytic approach for levulinic acid production from liquid hydrolysates (by-product of biomass utilization).