10489-79-9Relevant articles and documents
Nb2O5?nH2O as a heterogeneous catalyst with water-tolerant lewis acid sites
Nakajima, Kiyotaka,Baba, Yusuke,Noma, Ryouhei,Kitano, Masaaki,N. Kondo, Junko,Hayashi, Shigenobu,Hara, Michikazu
, p. 4224 - 4227 (2011)
Niobic acid, Nb2O5?nH2O, has been studied as a heterogeneous Lewis acid catalyst. NbO4 tetrahedra, Lewis acid sites, on Nb2O5?nH2O surface immediately form NbO4-H2O adducts in the presence of water. However, a part of the adducts can still function as effective Lewis acid sites, catalyzing the allylation of benzaldehyde with tetraallyl tin and the conversion of glucose into 5-(hydroxymethyl)furfural in water.
NMR structural study of fructans produced by Bacillus sp. 3B6, bacterium isolated in cloud water
Matulová, Mária,Husárová, Slavomíra,Capek, Peter,Sancelme, Martine,Delort, Anne-Marie
, p. 501 - 507 (2011)
Bacillus sp. 3B6, bacterium isolated from cloud water, was incubated on sucrose for exopolysaccharide production. Dialysis of the obtained mixture (MWCO 500) afforded dialyzate (DIM) and retentate (RIM). Both were separated by size exclusion chromatography. RIM afforded eight fractions: levan exopolysaccharide (EPS), fructooligosaccharides (FOSs) of levan and inulin types with different degrees of polymerization (dp 2-7) and monosaccharides fructose:glucose = 9:1. Levan was composed of two components with molecular mass ～3500 and ～100 kDa in the ratio 2.3:1. Disaccharide fraction contained difructose anhydride DFA IV. 1-Kestose, 6-kestose, and neokestose were identified as trisaccharides in the ratio 2:1:3. Fractions with dp 4-7 were mixtures of FOSs of levan (2,6-βFruf) and inulin (1,2-βFruf) type. DIM separation afforded two dominant fractions: monosaccharides with fructose: glucose ratio 1:3; disaccharide fraction contained sucrose only. DIM trisaccharide fraction contained 1-kestose, 6-kestose, and neokestose in the ratio1.5:1:2, penta and hexasaccharide fractions contained FOSs of levan type (2,6-βFruf) containing α-glucose. In the pentasaccharide fraction also the presence of a homopentasaccharide composed of 2,6-linked βFruf units only was identified. Nystose, inulin (1,2-βFruf) type, was identified as DIM tetrasaccharide. Identification of levan 2,6-βFruf and inulin 1,2-βFruf type oligosaccharides in the incubation medium suggests both levansucrase and inulosucrase enzymes activity in Bacillus sp. 3B6.
Mechanism for the formation and growth of carbonaceous spheres from sucrose by hydrothermal carbonization
Qi, Yujie,Zhang, Mu,Qi, Lin,Qi, Yang
, p. 20814 - 20823 (2016)
We report a new three-step mechanism for the formation and growth of carbonaceous spheres by hydrothermal carbonization of saccharides using sucrose as a precursor material. Carbonaceous spheres with small diameters and narrow size distribution were synthesized via a rapid heating route, and a notable phenomenon of a sudden drop in the mean diameter of the carbonaceous spheres at low concentration with the extension of time was observed. The morphology, chemical structure of carbonaceous spheres and the chemical composition of residual solutions were analysed by field emission scanning electron microscope (FESEM), Fourier transform infrared spectroscopy (FT-IR) and solution 13C nuclear magnetic resonance (NMR) respectively. Based on these results, evolution of solid products is clearly revealed. The formation contains two stages, and oversaturation of primary particles attributed to autocatalysis of fructose by the yielded acid (formic acid) results in the appearance of large amounts of carbonaceous spheres in the second stage of formation, which accounts for the sudden drop in mean diameter.
Hydrogenation of crude and purified d-glucosone generated by enzymatic oxidation of d-glucose
Aho, Atte,Lassfolk, Robert,Leino, Reko,Murzin, Dmitry Yu.
, p. 30476 - 30480 (2020/09/11)
D-Fructose is an important starting material for producing furfurals and other industrially important chemicals. While the base-catalyzed and enzymatic conversion of d-glucose to d-fructose is well known, the employed methods typically provide limited conversion. d-Glucosone can be obtained from d-glucose by enzymatic oxidation at the C2 position and, subsequently, selectively hydrogenated at C1 to form d-fructose. This work describes an investigation on the hydrogenation of d-glucosone, using both chromatographically purified and crude material obtained directly from the enzymatic oxidation, subjected to filtration and lyophilization only. High selectivities towards d-fructose were observed for both starting materials over a Ru/C catalyst. Hydrogenation of the crude d-glucosone was, however, inhibited by the impurities resulting from the enzymatic oxidation process. Catalyst deactivation was observed in the case of both starting materials.
FeVO4 decorated –SO3H functionalized polyaniline for direct conversion of sucrose to 2,5-diformylfuran & 5-ethoxymethylfurfural and selective oxidation reaction
Kumar, Abhinav,Srivastava, Rajendra
, p. 68 - 79 (2019/01/08)
In this study, a multi-functional catalyst, FeVO4 supported –SO3H functionalized polyaniline is prepared. First FeVO4 supported polyaniline is prepared. Then the resultant material is sulfonated using chlorosulphonic acid to obtain FeVO4 supported –SO3H functionalized polyaniline. This multi-functional catalyst exhibits excellent activity in the synthesis of 5-hydroxymethylfurfural from sucrose and oxidation of a wide range of aromatic and aliphatic alcohols. Further, the catalyst exhibits very good activity in the one-pot direct conversion of sucrose/fructose to 2,5-diformylfuran (DFF) and 5-ethoxymethylfurfural (EMF). This catalytic process involves the economical sucrose as a reactant and economical multi-functional catalyst based on polyaniline. In this one-pot, two-step process, -SO3H functionalized polyaniline is used in the first step for the conversion of sucrose to 5-hydroxymethylfurfural (HMF) followed by selective oxidation of HMF to DFF using FeVO4 sites present in the multi-functional catalyst. Moreover, acidic sites present in the multi-functional catalyst are suitable for the conversion of sucrose/fructose/HMF to EMF. Furthermore, molecular oxygen (1 atmosphere, 10 ml/min) is used as an eco-friendly and economical oxidant for the selective oxidation of a wide range of aromatic and aliphatic alcohols to aldehydes. The multi-functional catalyst presented here has been easily separated and recycled that make the process sustainable and economical for commercial perspectives.
