The primary interest to this study was to investigate the effect of milling parameters on the size of hydrophobically modified starch particles, aiming to produce small, uniformly sized modified starch microspheres. O...The primary interest to this study was to investigate the effect of milling parameters on the size of hydrophobically modified starch particles, aiming to produce small, uniformly sized modified starch microspheres. Octie, a commercial product originated from cornstarch modified using Octenyl Succinate Anhydride (OSA), was dispersed (3 wt%) using different media (water or ethanol) and subsequently wet-milled using a beads mill with zirconium beads at a rotation of 6,000 rpm up to 30 min. It was found that milling Octie in water dispersion for 3 min resulted in the smallest mean particle size (2.04 i 0.91 ktm), compared to unmilled modified starch granules (15.2 ~ 6.0 lam). Granular size and morphology changed considerably with further milling. For instance, very dense clusters with variable particle sizes (20.6 ~ 10.0 lam) were obtained after 30 min milling. As depicted by Scanning Electronic Microscopy, a large number of particles were apparently flattened during the milling process rather than broken, forming aggregates. Ultimately, within the range of experimental conditions tested, production of sub-micron modified starch particles was not possible.展开更多
UO2+, which is extracted from the aqueous phase into the 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide(C2mim NTf2) ionic liquid ph^ase with octyl(phenyl)-N,N-diisobutylcarbamoylmethylphosphine o...UO2+, which is extracted from the aqueous phase into the 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide(C2mim NTf2) ionic liquid ph^ase with octyl(phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide(CMPO), can be stripped by supercritical CO2. Trioctylphosphine oxide(TOPO), the modifier added to the supercritical CO2 phase, enhances the stripping efficiency by up to 99%.展开更多
Carbon-enriched lignocelluloses are regarded as the perfect alternative for nonrenewable fossil fuel, and have a great potential to alleviate the increasing energy crisis and climate change. However, the tightly coval...Carbon-enriched lignocelluloses are regarded as the perfect alternative for nonrenewable fossil fuel, and have a great potential to alleviate the increasing energy crisis and climate change. However, the tightly covalent structure and strong intra and in- ter-molecular hydrogen bonding in lignoceUulose make it high recalcitrance to transformation due to the poor solubility in wa- ter or common organic solvents. Dissolution and transformation of lignocellulose and its constituents in ionic liquids have therefore attracted much attention recently due to the tunable physical-chemical properties. Here, ionic liquids with excellent dissolving capability for biomass and its ingredients were examined. The technologies for lignocellulose biorefining in the presence of ionic liquid solvents or catalysts were also summarized. Some pertinent suggestions for the future catalytic conver- sion and unitization of this sustained carbon-rich resource are proposed.展开更多
文摘The primary interest to this study was to investigate the effect of milling parameters on the size of hydrophobically modified starch particles, aiming to produce small, uniformly sized modified starch microspheres. Octie, a commercial product originated from cornstarch modified using Octenyl Succinate Anhydride (OSA), was dispersed (3 wt%) using different media (water or ethanol) and subsequently wet-milled using a beads mill with zirconium beads at a rotation of 6,000 rpm up to 30 min. It was found that milling Octie in water dispersion for 3 min resulted in the smallest mean particle size (2.04 i 0.91 ktm), compared to unmilled modified starch granules (15.2 ~ 6.0 lam). Granular size and morphology changed considerably with further milling. For instance, very dense clusters with variable particle sizes (20.6 ~ 10.0 lam) were obtained after 30 min milling. As depicted by Scanning Electronic Microscopy, a large number of particles were apparently flattened during the milling process rather than broken, forming aggregates. Ultimately, within the range of experimental conditions tested, production of sub-micron modified starch particles was not possible.
基金supported by the National Natural Science Foundation of China(91226112)
文摘UO2+, which is extracted from the aqueous phase into the 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide(C2mim NTf2) ionic liquid ph^ase with octyl(phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide(CMPO), can be stripped by supercritical CO2. Trioctylphosphine oxide(TOPO), the modifier added to the supercritical CO2 phase, enhances the stripping efficiency by up to 99%.
基金financial support of the National Natural Science Foundation of China (20876055, 21076085)the Natural Science Foundation of Guangdong Province (S2011020001472)the Fundamental Research Funds for the Central Universities, SCUT
文摘Carbon-enriched lignocelluloses are regarded as the perfect alternative for nonrenewable fossil fuel, and have a great potential to alleviate the increasing energy crisis and climate change. However, the tightly covalent structure and strong intra and in- ter-molecular hydrogen bonding in lignoceUulose make it high recalcitrance to transformation due to the poor solubility in wa- ter or common organic solvents. Dissolution and transformation of lignocellulose and its constituents in ionic liquids have therefore attracted much attention recently due to the tunable physical-chemical properties. Here, ionic liquids with excellent dissolving capability for biomass and its ingredients were examined. The technologies for lignocellulose biorefining in the presence of ionic liquid solvents or catalysts were also summarized. Some pertinent suggestions for the future catalytic conver- sion and unitization of this sustained carbon-rich resource are proposed.