Synthesis of Mesoporous Silica Nanoparticles Exhibiting Sulfonic Groups and Ionic Liquids toward Cellulose-to-5-Hydroxymethylfurfural (HMF) Biomass Conversion
| Autor: | Yin-Ying Lee, 李盈瑩 |
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| Rok vydání: | 2012 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 100 This study focuses on the direct conversion of cellulose to 5-hydroxymethylfurfural (HMF) in dimethylsulfoxide (DMSO) systems by utilizing a series of sulfonic group (HSO3) and ionic liquid (ILs) functionalized mesoporous silica nanoparticles (MSNs) as heterogeneous solid catalysts. We first synthesized MSNs with pore size of 40 nm, namely large-pored MSN (LPMSN), and then functionalized LPMSN with acid groups (HSO3-) and ILs to form bi-functionalized LPMSN through a co-condensation method. Additionally, we also synthesized LPMSN with acidic or ionic liquids sites alone (i.e., HSO3-LPMSN and ILs/CrCl2-LPMSN, respectively). The amounts of functional groups on the MSN-based catalysts were characterized by solid-state NMR and elemental analysis. Moreover, the kinetics profiles of the systems with and without the catalysts were studied, and we derived that the reaction orders, activation energies and rate constants were alternated in the presence of catalysts. In particular, the Ea of the fructose-to-HMF conversion decreased from 80.05 kJ/mol to 67.5 kJ/mol. Finally, four materials (i.e., LPMSN, HSO3-LPMSN, ILs/CrCl2-LPMSN and bi-functionalized ([HSO3+(ILs/CrCl2)]-) LPMSN) were separately used as catalysts in the conversion of cellulose, cellobiose, glucose and fructose to HMF in the DMSO system. The HPLC results indicated that the highest yields of HMF converted from fructose, glucose, cellobiose and cellulose (i.e., 80.64%, 6.86%, 4.94% and 7.42%, respectively) could be obtained in the presence of [HSO3+(ILs/CrCl2)]-LPMSN or ILs/CrCl2-LPMSN catalysts. This is the first report of the generation of HMF directly from various sources (cellulose, cellobiose, glucose, and fructose) using funtionalized MSN as catalysts in DMSO systems. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
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