Four monodentate P-ligands and their mixtures（six groups of double-ligand systems,four groups of triple-ligand systems and one group of tetra-ligand system）were used with Rh（acac）（CO）2（acac=acetylacetonate）or...Four monodentate P-ligands and their mixtures（six groups of double-ligand systems,four groups of triple-ligand systems and one group of tetra-ligand system）were used with Rh（acac）（CO）2（acac=acetylacetonate）or Rh（acac）CO（PPh3）as the catalyst in the hydroformylation reaction of 1-butene.It was found that different Rh catalysts showed little difference in the catalysis performance.The general order of catalysis performance is doubleligand system 〉 single-ligand system〉triple-ligand system 〉 tetra-ligand system.Some synergistic effect in the double-ligand system was detected which needs a further investigation.展开更多
To study the temperature sensitivity of the destruction of organic compounds in supercritical water oxidation process （SCWO）, oxidation effects of twelve chemicals in supercritical water were investigated. The SCWO ...To study the temperature sensitivity of the destruction of organic compounds in supercritical water oxidation process （SCWO）, oxidation effects of twelve chemicals in supercritical water were investigated. The SCWO reaction rates of different compounds improved to varying degrees with the increase of temperature, so the highest slope of the temperature-effect curve （/max） was defined as the maximum ratio of removal ratio to working temperature. It is an important index to stand for the temperature sensitivity effect in SCWO. It was proven that the higher imax is, the more significant the effect of temperature on the SCWO effect is. Since the high-temperature area of SCWO equipment is subject to considerable damage from fatigue, the temperature is of great significance in SCWO equipment operation. Generally, most compounds （/max 〉 0.25） can be completely oxidized when the reactor temperature reaches 500~C. However, some compounds （/max 〉 0.25） need a higher temperature for complete oxidation, up to 560~C. To analyze the correlation coefficients between/max and various molecular descriptors, a quantum chemical method was used in this study. The structures of the twelve organic compounds were optimized by the Density Functional Theory B3LYP/6-311G method, as well as their quantum properties. It was shown that six molecular descriptors were negatively correlated to imax while other three descriptors were positively correlated to imax. Among them, dipole moment had the greatest effect on the oxidation thermodynamics of the twelve organic compounds. Once a correlation between molecular descriptors and imax is established, SCWO can be run at an appropriate temperature according to molecular structure.展开更多
基金Supported by the National Natural Science Foundation of China(21306227)the Science Foundation of China University of Petroleum,Beijing(C201604)
文摘Four monodentate P-ligands and their mixtures（six groups of double-ligand systems,four groups of triple-ligand systems and one group of tetra-ligand system）were used with Rh（acac）（CO）2（acac=acetylacetonate）or Rh（acac）CO（PPh3）as the catalyst in the hydroformylation reaction of 1-butene.It was found that different Rh catalysts showed little difference in the catalysis performance.The general order of catalysis performance is doubleligand system 〉 single-ligand system〉triple-ligand system 〉 tetra-ligand system.Some synergistic effect in the double-ligand system was detected which needs a further investigation.
基金supported by the National Natural Science Foundation of China(No.21177083,20937003)the Program for New Century Excellent Talents in University
文摘To study the temperature sensitivity of the destruction of organic compounds in supercritical water oxidation process （SCWO）, oxidation effects of twelve chemicals in supercritical water were investigated. The SCWO reaction rates of different compounds improved to varying degrees with the increase of temperature, so the highest slope of the temperature-effect curve （/max） was defined as the maximum ratio of removal ratio to working temperature. It is an important index to stand for the temperature sensitivity effect in SCWO. It was proven that the higher imax is, the more significant the effect of temperature on the SCWO effect is. Since the high-temperature area of SCWO equipment is subject to considerable damage from fatigue, the temperature is of great significance in SCWO equipment operation. Generally, most compounds （/max 〉 0.25） can be completely oxidized when the reactor temperature reaches 500~C. However, some compounds （/max 〉 0.25） need a higher temperature for complete oxidation, up to 560~C. To analyze the correlation coefficients between/max and various molecular descriptors, a quantum chemical method was used in this study. The structures of the twelve organic compounds were optimized by the Density Functional Theory B3LYP/6-311G method, as well as their quantum properties. It was shown that six molecular descriptors were negatively correlated to imax while other three descriptors were positively correlated to imax. Among them, dipole moment had the greatest effect on the oxidation thermodynamics of the twelve organic compounds. Once a correlation between molecular descriptors and imax is established, SCWO can be run at an appropriate temperature according to molecular structure.
