Acyl chloride can efficiently be converted into anhydride under solid liquid phase transfer catalysis by using bis(triphenylphosphine)cobalt dichloride or bis(triphenylphospine)palladium dichloride as the catalyst.
The crosslinked chitosan was grafted by 4'-formal benzo-15-crown-5 to obtaine crosslinked chitosan with 4'-formal benzo- 15-crown-5(CCTS-N=CH-B- 15-C-5). Then it was loaded with palldium chloride to gain the heter...The crosslinked chitosan was grafted by 4'-formal benzo-15-crown-5 to obtaine crosslinked chitosan with 4'-formal benzo- 15-crown-5(CCTS-N=CH-B- 15-C-5). Then it was loaded with palldium chloride to gain the heterogeneous catalyst, which was easily isolated from the reaction system. The influences of the Pd content of the catalyst, solvent, and temperature on asymmetric hydrogenation of a-phenylethanone have been studied. The catalyst has been found to catalyze the hydrogenation ofa-phenylethanone into the chiral alcohol, α-phenyl ethanol under the mild condition. The optical yield of (R)- 1-phenylethanol could be obtained as 97.1% under the following conditions: temperature, 30℃; solvent, ethanol; Pd content, 1.43 mmol/g; substrate concentration, 0.02 g/mL due to the cooperative effect of crown ether and chitosan polymer. The stability of this catalyst was also studied at the same time. This chiral natural crosslinked chitosan-palladium complex catalyst could be reused without appreciable change in optical catalytic activity, which will be useful for designing crosslinked-chitosan-based adsorption for metal ions for asymmetric hydrogenation.展开更多
The possibility and feasibility of using supercritical fluid СО<sub>2</sub> extraction process have been investigated and described in the book as part of the task of spent catalysts regeneration. The an...The possibility and feasibility of using supercritical fluid СО<sub>2</sub> extraction process have been investigated and described in the book as part of the task of spent catalysts regeneration. The analysis of deactivating compounds has been carried out for industrial catalysts such as: 1) palladium catalyst G-58E of ethane-ethylene fraction hydrogenation;2) nickel/kieselguhr catalyst of process of separating acetylenic compounds from isoprene;3) active aluminum oxide catalyst of methyl phenyl carbinol dehydration process;4) palladium catalyst LD-265 of hydrocarbons hydrogenation process;5) nickel-molybdenum catalysts DN-3531 and Criterion 514 of kerosene hydrotreating process. The results of the study of catalyst deactivating compounds solubility in pure supercritical carbon dioxide and supercritical carbon dioxide are modified with polar additive. The results of the solubility study are described using the Peng-Robinson equation of state. The results of the implementation of the supercritical fluid СО<sub>2</sub> extraction process with respect to deactivated industrial catalyst samples have been provided. A comparison of the characteristics of samples of catalysts regenerated using the traditional approach and the SC-CO<sub>2</sub> extraction process has been conducted. The possibility of using supercritical fluid CO<sub>2</sub> impregnation process in the synthesis of a palladium catalyst has been investigated. The synthesis of palladium chloride-based organometallic complexes has been carried out. The results of the study of solubility thereof in supercritical carbon dioxide have been provided. A dynamic supercritical fluid CO<sub>2</sub> impregnation process condition has been implemented. A comparison of the characteristics of palladium catalyst samples synthesized using the conventional approach and SC-CO<sub>2</sub> impregnation process has been conducted and presented in the book.展开更多
Polystyrene-supported hydroquinone (PS-HQ) is presented as an in situ polymeric cocatalyst to replace polystyrenesupported benzoquinone (PS-BQ) in the PdCl2-catalyzed acetalization of methyl acrylate with methanol...Polystyrene-supported hydroquinone (PS-HQ) is presented as an in situ polymeric cocatalyst to replace polystyrenesupported benzoquinone (PS-BQ) in the PdCl2-catalyzed acetalization of methyl acrylate with methanol in supercritical carbon dioxide (scCO2) under oxygen atmosphere. Due to deletion of H2O2 oxidation step, PS-HQ is more convenient and relatively inexpensive.展开更多
A novel supported liquid phase film catalyst: Supported PdCl2-(n-C4H9),N+Cl- molten salts was found to be an effective catalyst with good stability for selective hydrodechlorination of CCl2F2 (CFC-12) to its alternati...A novel supported liquid phase film catalyst: Supported PdCl2-(n-C4H9),N+Cl- molten salts was found to be an effective catalyst with good stability for selective hydrodechlorination of CCl2F2 (CFC-12) to its alternatives CH2F2 and CHClF2. Addition of CoCl2, GaCl3 and CuCl2 to PdCl2-(n-C4H9),N+Cl- modifies the catalytic performance of supported molten salts.展开更多
A novel method of patterning high precision copper conductive micropatterns on flexible polymer substrate(polyimide)is developed.We utilized the coordination effect between palladium salts and pyridine structures to f...A novel method of patterning high precision copper conductive micropatterns on flexible polymer substrate(polyimide)is developed.We utilized the coordination effect between palladium salts and pyridine structures to fix the palladium chloride(PdCl_(2))on the surface of polymer film while the 2,6-dimethylpyridine structures formed in the specific areas under ultraviolet light guaranteed the resolution of final patterns.Simultaneous thermal reduction of PdCl_(2) on the surface can be achieved in the process of thermal cyclization of the polymer substrate.As a consequence,the obtained polyimide(PI)film can be patterned with conductive copper micropatterns directly by electroless plating.In particular,we accomplished the deposition of high precision copper pattern with a minimum line width of 50μm and minimum line spacing of 20μm on PI thin films(thickness~10μm)by electroless plating.The prepared conductive copper micropatterns exhibit a low resistivity of 1.78μΩ·cm the same as the pure block copper.And the relationship between the structures of the polymer chains and the physical properties of polymer substrates,such as the dimensional stability,mechanical and dielectric properties were also discussed in detail.This simple and novel method of patterning metal on the polymer surface does not need to achieve the catalytic metal adhesion required for electroless plating at the cost of destroying the substrate surface and avoiding the introduction of unstable interlayers.This patterning method is compatible with the current roll-to-roll production process and can be used to develop high-performance micro-integrated circuits.展开更多
Carbon supported PdCl_2 is highly active in catalyzing acetylene hydrochlorination reaction, but deactivates rather quickly. Upon nitrogen doping in the carbon structure, the stability of the PdCl_2 catalysts is signi...Carbon supported PdCl_2 is highly active in catalyzing acetylene hydrochlorination reaction, but deactivates rather quickly. Upon nitrogen doping in the carbon structure, the stability of the PdCl_2 catalysts is significantly improved. Furthermore, the results show that 900 ℃ is a preferred doping temperature. The acetylene conversion keeps above 90% even after 1200 min time on stream whereas the one without nitrogen doping drops to below 10% after 450 min. The stabilizing mechanism of nitrogen doping on catalyst was studied.展开更多
文摘Acyl chloride can efficiently be converted into anhydride under solid liquid phase transfer catalysis by using bis(triphenylphosphine)cobalt dichloride or bis(triphenylphospine)palladium dichloride as the catalyst.
基金Funded by the State Educational Committe Doctoral Foundation of China(No.2000048615)
文摘The crosslinked chitosan was grafted by 4'-formal benzo-15-crown-5 to obtaine crosslinked chitosan with 4'-formal benzo- 15-crown-5(CCTS-N=CH-B- 15-C-5). Then it was loaded with palldium chloride to gain the heterogeneous catalyst, which was easily isolated from the reaction system. The influences of the Pd content of the catalyst, solvent, and temperature on asymmetric hydrogenation of a-phenylethanone have been studied. The catalyst has been found to catalyze the hydrogenation ofa-phenylethanone into the chiral alcohol, α-phenyl ethanol under the mild condition. The optical yield of (R)- 1-phenylethanol could be obtained as 97.1% under the following conditions: temperature, 30℃; solvent, ethanol; Pd content, 1.43 mmol/g; substrate concentration, 0.02 g/mL due to the cooperative effect of crown ether and chitosan polymer. The stability of this catalyst was also studied at the same time. This chiral natural crosslinked chitosan-palladium complex catalyst could be reused without appreciable change in optical catalytic activity, which will be useful for designing crosslinked-chitosan-based adsorption for metal ions for asymmetric hydrogenation.
文摘The possibility and feasibility of using supercritical fluid СО<sub>2</sub> extraction process have been investigated and described in the book as part of the task of spent catalysts regeneration. The analysis of deactivating compounds has been carried out for industrial catalysts such as: 1) palladium catalyst G-58E of ethane-ethylene fraction hydrogenation;2) nickel/kieselguhr catalyst of process of separating acetylenic compounds from isoprene;3) active aluminum oxide catalyst of methyl phenyl carbinol dehydration process;4) palladium catalyst LD-265 of hydrocarbons hydrogenation process;5) nickel-molybdenum catalysts DN-3531 and Criterion 514 of kerosene hydrotreating process. The results of the study of catalyst deactivating compounds solubility in pure supercritical carbon dioxide and supercritical carbon dioxide are modified with polar additive. The results of the solubility study are described using the Peng-Robinson equation of state. The results of the implementation of the supercritical fluid СО<sub>2</sub> extraction process with respect to deactivated industrial catalyst samples have been provided. A comparison of the characteristics of samples of catalysts regenerated using the traditional approach and the SC-CO<sub>2</sub> extraction process has been conducted. The possibility of using supercritical fluid CO<sub>2</sub> impregnation process in the synthesis of a palladium catalyst has been investigated. The synthesis of palladium chloride-based organometallic complexes has been carried out. The results of the study of solubility thereof in supercritical carbon dioxide have been provided. A dynamic supercritical fluid CO<sub>2</sub> impregnation process condition has been implemented. A comparison of the characteristics of palladium catalyst samples synthesized using the conventional approach and SC-CO<sub>2</sub> impregnation process has been conducted and presented in the book.
文摘Polystyrene-supported hydroquinone (PS-HQ) is presented as an in situ polymeric cocatalyst to replace polystyrenesupported benzoquinone (PS-BQ) in the PdCl2-catalyzed acetalization of methyl acrylate with methanol in supercritical carbon dioxide (scCO2) under oxygen atmosphere. Due to deletion of H2O2 oxidation step, PS-HQ is more convenient and relatively inexpensive.
文摘A novel supported liquid phase film catalyst: Supported PdCl2-(n-C4H9),N+Cl- molten salts was found to be an effective catalyst with good stability for selective hydrodechlorination of CCl2F2 (CFC-12) to its alternatives CH2F2 and CHClF2. Addition of CoCl2, GaCl3 and CuCl2 to PdCl2-(n-C4H9),N+Cl- modifies the catalytic performance of supported molten salts.
基金financially supported by the National Natural Science Foundation of China(No.51833011)the National Key Research and Development Program of China(No.2016YT03C077)。
文摘A novel method of patterning high precision copper conductive micropatterns on flexible polymer substrate(polyimide)is developed.We utilized the coordination effect between palladium salts and pyridine structures to fix the palladium chloride(PdCl_(2))on the surface of polymer film while the 2,6-dimethylpyridine structures formed in the specific areas under ultraviolet light guaranteed the resolution of final patterns.Simultaneous thermal reduction of PdCl_(2) on the surface can be achieved in the process of thermal cyclization of the polymer substrate.As a consequence,the obtained polyimide(PI)film can be patterned with conductive copper micropatterns directly by electroless plating.In particular,we accomplished the deposition of high precision copper pattern with a minimum line width of 50μm and minimum line spacing of 20μm on PI thin films(thickness~10μm)by electroless plating.The prepared conductive copper micropatterns exhibit a low resistivity of 1.78μΩ·cm the same as the pure block copper.And the relationship between the structures of the polymer chains and the physical properties of polymer substrates,such as the dimensional stability,mechanical and dielectric properties were also discussed in detail.This simple and novel method of patterning metal on the polymer surface does not need to achieve the catalytic metal adhesion required for electroless plating at the cost of destroying the substrate surface and avoiding the introduction of unstable interlayers.This patterning method is compatible with the current roll-to-roll production process and can be used to develop high-performance micro-integrated circuits.
基金supported by the National Science Foundation of China(21425312,21373207,21321002)
文摘Carbon supported PdCl_2 is highly active in catalyzing acetylene hydrochlorination reaction, but deactivates rather quickly. Upon nitrogen doping in the carbon structure, the stability of the PdCl_2 catalysts is significantly improved. Furthermore, the results show that 900 ℃ is a preferred doping temperature. The acetylene conversion keeps above 90% even after 1200 min time on stream whereas the one without nitrogen doping drops to below 10% after 450 min. The stabilizing mechanism of nitrogen doping on catalyst was studied.