Reductive Conversion of Biomass-Derived Furancarboxylic Acids with Retention of Carboxylic Acid Moiety

Abstract

Catalytic reduction systems of 2-furancarboxylic acid (FCA) and 2,5-furandicarboxylic acid (FDCA) with H2 without reduction of the carboxyl groups are reviewed. FCA and FDCA are produced from furfural and 5-hydroxymethylfurfural which are important platform chemicals in biomass conversions. Furan ring hydrogenation to tetrahydrofuran-2-carboxylic acid (THFCA) and tetrahydrofuran-2,5-dicarboxylic acid (THFDCA) easily proceeds over Pd catalysts. Hydrogenolysis of one C–O bond in the furan ring produces 5-hydroxyvaleric acid (5-HVA) and 2-hydroxyadipic acid. 2-Hydroxyvaleric acid is not produced in the reported systems. 5-HVA can be produced as the lactone form (δ-valerolactone; DVL) or as the esters depending on the solvent. These reactions proceed over Pt catalysts with good yields (~ 70%) at optimized conditions. Hydrogenolysis of two C–O bonds in the furan ring produces valeric acid and adipic acid, the latter of which is a very important chemical in industry and its production from biomass is of high importance. Adipic acid from FDCA can be produced directly over Pt-MoOx catalyst, indirectly via hydrogenation and hydrodeoxygenation as one-pot reaction using the combination of Pt and acid catalysts such as Pt/niobium oxide, or indirectly via two-step reaction composed of hydrogenation catalyzed by Pd and hydrodeoxygenation catalyzed by iodide ion in acidic conditions. Only the two-step method can give good yield of adipic acid at present.

Raney Ni as a Versatile Catalyst for Biomass Conversion

“…157,158 Upgrading of LA to γ-valerolactone (GVL), which plays a central role in the biomass-based carbon cycle, is the most classical reaction. 157,159 In 2013, Mika and co-workers described the synthesis of GVL in a continuousflow reactor with various heterogeneous catalysts (10% Pd/C, 5% Ru/C, and Raney Ni CatCart) and found that the Raney Ni catalyst resulted in activity lower than that of Ru/C. 160 Later, Rong and co-workers investigated the same reaction and compared the RQ Ni with the normal Raney Ni catalyst.…”

“…Levulinic acid (LA), which can be simply obtained via acid-catalyzed dehydration of carbohydrates, is another vitally important platform chemical and has been widely used as a substrate for the synthesis of value-added chemicals and fuels in recent years. , Upgrading of LA to γ-valerolactone (GVL), which plays a central role in the biomass-based carbon cycle, is the most classical reaction. , In 2013, Mika and co-workers described the synthesis of GVL in a continuous-flow reactor with various heterogeneous catalysts (10% Pd/C, 5% Ru/C, and Raney Ni CatCart) and found that the Raney Ni catalyst resulted in activity lower than that of Ru/C . Later, Rong and co-workers investigated the same reaction and compared the RQ Ni with the normal Raney Ni catalyst.…”

Recent Advances in the Catalytic Upgrading of Biomass Platform Chemicals Via Hydrotalcite-Derived Metal Catalysts

“…have been obtained by the functionalization/ defunctionalization of hydroxyl or/and aldehyde groups with different catalytic systems [41]. Hydrodeoxygenation or acidolysis of the furan ring can produce alkanes, alcohols, furancarboxylic acids, LA, or γ-valerolactone (GVL) [42,43]. During all these transformations, catalysts are vitally important in improving yield and selectivity.…”

Metal–Organic Framework-Based Solid Acid Materials for Biomass Upgrade

“…Similar to the glucose to HMF conversion mentioned above, xylose can be transformed into furfural via Lewis acid-catalyzed isomerization followed by Brønsted acid-catalyzed dehydration (Scheme 5) [108,109]. Since pristine MIL-101(Cr), limited by its relatively low Brønsted acidity, only displayed unsatisfied catalytic performance in the application of xylose to furfural transformation, several types of MIL-101(Cr)-based materials with dual-acid sites were developed to promote catalytic conversion.…”