Organic Carbonates: Efficient Extraction Solvents for the Synthesis of HMF in Aqueous Media with Cerium Phosphates as Catalysts

Abstract

We describe a process for the selective conversion of C6 -polyols into 5-hydroxymethylfurfural (5-HMF) in biphasic systems of organic carbonate/water (OC/W), with cerium(IV) phosphates as catalysts. Different reaction parameters such as the OC/W ratio, catalyst loading, reaction time, and temperature, were investigated for the dehydration of fructose. Under the best reaction conditions, a yield of 67.7 % with a selectivity of 93.2 % was achieved at 423 K after 6 h of reaction using [(Ce(PO4)1.5 (H2 O)(H3 O)0.5 (H2 O)0.5)] as the catalyst. A maximum yield of 70 % with the same selectivity was achieved after 12 h. At the end of the reaction, the catalyst was removed by centrifugation, the organic phase was separated from water and evaporated in vacuo (with solvent recovery), and solid 5-HMF was isolated (purity >99 %). The recovery and reuse of the catalyst and the relationship between the structure of the OC and the efficiency of the extraction are discussed. The OC/W system influences the lifetime of the catalysts positively compared to only water.

Sustainable Synthesis of Oxalic and Succinic Acid through Aerobic Oxidation of C6 Polyols Under Mild Conditions

“…[5].A ll the reaction products were analyzed by using aJ asco HPLC equipped with arefractive index (RI) detector and aPhenomenex Rezex RHM Monosaccharide H + (8 %) 300 7.8 mm at 343 K. A0 .005 Ns olution of sulfuric acid was used as the mobile phase. 99 %, 5-formyl-2-furoic acid > 99 %, 2,5-furandicarboxylic acid > 99 %, d-glucose, d-fructose, oxalic acid, formic acid, succinic acid and levulinic acid as standards were purchased from Sigma-Aldrich.…”

“…5-(hydroxymethyl)-furfural was prepared as reported in Ref. [5].A ll the reaction products were analyzed by using aJ asco HPLC equipped with arefractive index (RI) detector and aPhenomenex Rezex RHM Monosaccharide H + (8 %) 300 7.8 mm at 343 K. A0 .005 Ns olution of sulfuric acid was used as the mobile phase. The flow rate was between 0.5-0.9 mL min À1 .T he concentration of the substrate and the reaction products was determined using an RI detector.…”

“…The need to establish environmentally friendly chemical processes is imperative and requires the development of novel and cost-effective methods for the prevention of pollution. [2b] Among renewable feedstock, lignocellulosic biomass has attracted considerable attention owing to its potentiala sasource of aw ide range of platform chemicals such as C6-polyols, [4] 5-hydroxymethylfurfural (5-HMF), [5] levulinic acid (LA) [6] or formica cid (FA). [3] Recently,e ven CO 2 has been taken into seriousc onsideration as ab uilding block for chemicals or as a source of carbonf or fuels.…”

“…[3] Recently,e ven CO 2 has been taken into seriousc onsideration as ab uilding block for chemicals or as a source of carbonf or fuels. [2b] Among renewable feedstock, lignocellulosic biomass has attracted considerable attention owing to its potentiala sasource of aw ide range of platform chemicals such as C6-polyols, [4] 5-hydroxymethylfurfural (5-HMF), [5] levulinic acid (LA) [6] or formica cid (FA). [7] Among such chemicals, 5-HMF,s ynthesized by dehydration of fructose or directly from glucose, [8] is considered as one of the most important intermediates.I ts furan structure bearing an aldehyde and ah ydroxyl moiety can be transformed into numerous high-value chemicals capable of replacing their analogs synthesized from fossil fuels (Scheme 1).…”

4 Production of aquatic biomass and extraction of bio-oil

“…Oil and chemicals can be extracted from biomass by using a variety of technologies of different intensity (destructive, semidestructive, and nondestructive) (Aresta et al 2005b;Dibenedetto et al 2012). There is a relation between the softness-hardness of the technology used and the complexity of the structure of the chemicals extracted.…”