Biomass conversion to alkyl levulinates using heteropoly acid carbon mesoporous composites

With regards to the importance of biomass conversion into valuable compounds such as alkyl levulinate (AL), herein, the synthesis of butyl levulinate (BL) and ethyl levulinate (EL) from various carbohydrates (fructose, glucose, and sucrose) was studied using a series of phosphomolybdic acid (HPMo) catalysts supported on carbon mesoporous CMK-8 and CMK-3. The effect of acid loading as well as the influence of carbon mesoporous on carbohydrate conversion into ALs was investigated. Furthermore, mono lacunar y phosphomolybdate catalyst supported on CMK-8 was prepared and its efficiency was compared to the optimum catalyst (CMK-HPM-50). XRD, N-2 adsorption-desorption, SEM-EDX, FT-IR, TGA-DTA, and TEM analysis were performed for characterization of the synthesized catalysts. Compared to other catalysts, CMK-HPM-50 with 50% acid loading on CMK-8 showed the best results for the BL and EL production with yields of 42, 57, 66% and 53, 64, 72% from sucrose, glucose, and fructose, respectively, due to the unique 3D cubic mesostructure of CMK-8 and high Bronsted acidity of immobilized HPMo. The conversion of carbohydrates to ALs (BL and EL) was almost completed (> 98%) at all of the experiments. Various factors including, the amount of catalyst, reaction time, and reaction temperature were studied. According to the results, 50 mg of CMK-HPM-50 catalyst, 180 degrees C for the reaction temperature, and 3 h for the reaction time were selected as optimum conditions. (c) 2022 Institution of Chemical Engineers. Published by Elsevier Ltd. All rights reserved.

Automated summary

In this study, alkyl levulinates (butyl levulinate and ethyl levulinate) were successfully synthesized from carbohydrates (fructose, glucose, and sucrose) using catalysts supported on carbon mesoporous materials. The results showed that the choice of catalyst and reaction conditions significantly affected the yield of the desired products.