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First identification of primary nanoparticles in the aggregation of HMF.

Zhang M, Yang H, Liu Y, Sun X, Zhang D, Xue D - Nanoscale Res Lett (2012)

Bottom Line: The residual solution is found to contain a massive number of primary nanoparticles.Based on these observations, a mechanism involving the formation and aggregation of the nanoparticles is proposed.This mechanism differs considerably from the conventional understanding in the open literature.

View Article: PubMed Central - HTML - PubMed

Affiliation: School of Mechanical and Chemical Engineering and Centre for Energy, The University of Western Australia, 35 Stirling Highway, Perth, Western Australia, 6009, Australia. hong.yang@uwa.edu.au.

ABSTRACT
5-Hydroxymethylfurfural [HMF] is an important intermediate compound for fine chemicals. It is often obtained via hydrothermal treatment of biomass-derived carbohydrates, such as fructose, glucose and sucrose. This study investigates the formation of carbonaceous spheres from HMF created by dehydration of fructose under hydrothermal conditions. The carbonaceous spheres, ranging between 0.4 and 10 μm in diameter, have granulated morphologies both on the surface and in the interior. The residual solution is found to contain a massive number of primary nanoparticles. The chemical structure of the carbonaceous spheres was characterised by means of FTIR and NMR spectroscopies. Based on these observations, a mechanism involving the formation and aggregation of the nanoparticles is proposed. This mechanism differs considerably from the conventional understanding in the open literature.

No MeSH data available.


Related in: MedlinePlus

Schematic illustration of the formation mechanism of carbonaceous spheres from fructose under hydrothermal condition.
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Figure 5: Schematic illustration of the formation mechanism of carbonaceous spheres from fructose under hydrothermal condition.

Mentions: From all observations and analyses obtained in this study, we propose the following hypothesis as the formation mechanism of carbonaceous spheres from fructose under hydrothermal conditions, as schematically illustrated in Figure 5. Under hydrothermal conditions, fructose undergoes dehydration to form HMF. This has been proven in the literature [8,18]. HMF monomer has active functional groups, such as the hydroxyl terminal. This renders the HMF monomer the ability to polycondense via intra-molecular dehydration through reactions between the hydroxyl and H-terminals of different HMF monomers to form cross-linked furanic species. The continued growth in size of the cross-linked furanic species eventually results in the precipitation of the molecular clusters out of the solution into the primary carbonaceous nanoparticles. These primary nanoparticles, having inherited the functional groups of HMF on their surfaces, may continue to aggregate via the same polycondensation reactions as those causing the formation of the primary particles, leading to the formation of the large, near carbonaceous spheres. This concept, supported by the direct experimental evidence and the known chemistry of HMF, differs significantly from the conventional hypotheses in the open literature.


First identification of primary nanoparticles in the aggregation of HMF.

Zhang M, Yang H, Liu Y, Sun X, Zhang D, Xue D - Nanoscale Res Lett (2012)

Schematic illustration of the formation mechanism of carbonaceous spheres from fructose under hydrothermal condition.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3278355&req=5

Figure 5: Schematic illustration of the formation mechanism of carbonaceous spheres from fructose under hydrothermal condition.
Mentions: From all observations and analyses obtained in this study, we propose the following hypothesis as the formation mechanism of carbonaceous spheres from fructose under hydrothermal conditions, as schematically illustrated in Figure 5. Under hydrothermal conditions, fructose undergoes dehydration to form HMF. This has been proven in the literature [8,18]. HMF monomer has active functional groups, such as the hydroxyl terminal. This renders the HMF monomer the ability to polycondense via intra-molecular dehydration through reactions between the hydroxyl and H-terminals of different HMF monomers to form cross-linked furanic species. The continued growth in size of the cross-linked furanic species eventually results in the precipitation of the molecular clusters out of the solution into the primary carbonaceous nanoparticles. These primary nanoparticles, having inherited the functional groups of HMF on their surfaces, may continue to aggregate via the same polycondensation reactions as those causing the formation of the primary particles, leading to the formation of the large, near carbonaceous spheres. This concept, supported by the direct experimental evidence and the known chemistry of HMF, differs significantly from the conventional hypotheses in the open literature.

Bottom Line: The residual solution is found to contain a massive number of primary nanoparticles.Based on these observations, a mechanism involving the formation and aggregation of the nanoparticles is proposed.This mechanism differs considerably from the conventional understanding in the open literature.

View Article: PubMed Central - HTML - PubMed

Affiliation: School of Mechanical and Chemical Engineering and Centre for Energy, The University of Western Australia, 35 Stirling Highway, Perth, Western Australia, 6009, Australia. hong.yang@uwa.edu.au.

ABSTRACT
5-Hydroxymethylfurfural [HMF] is an important intermediate compound for fine chemicals. It is often obtained via hydrothermal treatment of biomass-derived carbohydrates, such as fructose, glucose and sucrose. This study investigates the formation of carbonaceous spheres from HMF created by dehydration of fructose under hydrothermal conditions. The carbonaceous spheres, ranging between 0.4 and 10 μm in diameter, have granulated morphologies both on the surface and in the interior. The residual solution is found to contain a massive number of primary nanoparticles. The chemical structure of the carbonaceous spheres was characterised by means of FTIR and NMR spectroscopies. Based on these observations, a mechanism involving the formation and aggregation of the nanoparticles is proposed. This mechanism differs considerably from the conventional understanding in the open literature.

No MeSH data available.


Related in: MedlinePlus