Promotion effect of mesopore on the conversion of carbohydrates to methyl levulinate over H-USY zeolite

Hyper‐cross‐linked polymer based carbonaceous materials as efficient catalysts for ethyl levulinate production from carbohydrates

“…Upon the request of green and sustainable development, substitution of homogeneous by heterogeneous catalysts is highly desirable to solve obvious problems such as corrosion, separation, regenerability and reuse. Therefore, a variety of heterogeneous catalysts such as metal oxides, heteropoly acids, carbonaceous materials and zeolites are reasonably designed and developed as the preferred catalysts to give moderate to high yields of alkyl levulinates . For instance, Zhang and Chen developed a series of metal salt‐modified carbon catalysts to catalyze fructose conversion in ethanol, in which 58% EL was attained after 3 h of reaction.…”

“…investigated the esterification of levulinic acid into EL using reusable silica‐included Wells–Dawson heteropolyacid as catalyst. Yang and coworkers applied hierarchical H‐USY zeolite for the direct transformation of glucose into methyl levulinate with an optimal yield of 54%. Meanwhile, modified zeolites such as sulfonic acid functionalized SBA‐15 and alumina‐coated SBA‐15 were also active in the conversion of carbohydrates into EL …”

“…Therefore, a variety of heterogeneous catalysts such as metal oxides, heteropoly acids, carbonaceous materials and zeolites are reasonably designed and developed as the preferred catalysts to give moderate to high yields of alkyl levulinates. 8, [15][16][17][18][19][20][21][22][23][24] For instance, Zhang and Chen 8 developed a series of metal salt-modified carbon catalysts to catalyze fructose conversion in ethanol, in which 58% EL was attained after 3 h of reaction. Baronetti et al 19 investigated the esterification of levulinic acid Scheme 1.…”

Catalytic Upgrading of Biomass‐Derived Sugars with Acidic Nanoporous Materials: Structural Role in Carbon‐Chain Length Variation

“…The presence of mesopores played an important role in facilitating the activity of H‐USY zeolite for the conversion of glucose into MLevu, owing to improved diffusion limitation. This was illustrated by the catalytic performance of H‐USY containing mesopores (H‐USY‐0.2), with a mesoporous volume of 0.172 cm 2 g −1 , which was prepared by dealumination with nitric acid (0.2 mol L −1 ), and was superior to that of the parent H‐USY zeolite under identical reaction conditions (Table , entries 3 and 4) …”

Design of Ordered Mesoporous Sulfonic Acid Functionalized ZrO2/organosilica Bifunctional Catalysts for Direct Catalytic Conversion of Glucose to Ethyl Levulinate

“…Acid‐catalyzed direct synthesis of EL from monosaccharides such as fructose or glucose in ethanol medium has been the most favorable approach„ and fructose is reported to give a significantly higher EL yield compared to glucose . Sustainable glucose is more cheap, and abundant than fructose; however, direct conversion of glucose to EL is more complex, and difficult than conversion of fructose because the process involves isomerization of glucose/ethyl glucoside to fructose/ethyl fructoside catalyzed predominantly by Lewis (L) acid sites . Subsequent successive dehydration of fructose/or ethyl fructoside to EL is mainly catalyzed by Brønsted (B) acid sites.…”