It was proved by ICP, fluorescence spectra and N 2 adsorption that the rare earth complex [C 5H 5NC 16H 33] [Eu(TTA) 4] is in the channel of Si-MCM-41 in the course of assembly. The rare earth complex of 67.9% is in t...It was proved by ICP, fluorescence spectra and N 2 adsorption that the rare earth complex [C 5H 5NC 16H 33] [Eu(TTA) 4] is in the channel of Si-MCM-41 in the course of assembly. The rare earth complex of 67.9% is in the channel, suggesting that the assembly of the complex molecular on the mesoporous MCM-41 was carried out mainly in the channel.展开更多
The composite mesoporous materials C2H5-MCM-41 are synthesized by multistep method,and its structure is characerized and evaluated.A solid-phase microextraction(SPME) method coupled to HPLC is proposed for the determi...The composite mesoporous materials C2H5-MCM-41 are synthesized by multistep method,and its structure is characerized and evaluated.A solid-phase microextraction(SPME) method coupled to HPLC is proposed for the determination of trace pyrene with C2H5-MCM-41 mesporous materials as the coating of extractor.Extraction time,extraction temperation,stirring rate,ionic strength,and desorption time had been optimized.The liner range is 0.15~150μg·L-1,detection limit is 0.062μg.L-1(S/N=3),whereas the RSD(n=5) range is 0.035%,which suggests that the sample pretreatment method of SPME is fast,convenient,recise,sensitive and solvent-free.展开更多
An efficient three-component synthesis of 3,4-dihydropyrimidinones using MCM-41 anchored sulfonic acid (MCM-41-R-SO3H) as a mild, heterogeneous catalyst for Biginelli reaction in CH3CN under reflux condition is desc...An efficient three-component synthesis of 3,4-dihydropyrimidinones using MCM-41 anchored sulfonic acid (MCM-41-R-SO3H) as a mild, heterogeneous catalyst for Biginelli reaction in CH3CN under reflux condition is described.展开更多
The AlMCM-41 molecular sieves with two different pore sizes are hydrothermally synthesized in the presence of surfactants with two different chain lengths. H-AlMCM-41 and Ru-Sn-B/H-AlMCM-41 which are prepared by the ...The AlMCM-41 molecular sieves with two different pore sizes are hydrothermally synthesized in the presence of surfactants with two different chain lengths. H-AlMCM-41 and Ru-Sn-B/H-AlMCM-41 which are prepared by the conventional ion-exchange and incipient wetness techniques of the AlMCM-41 show fair catalytic activity for esterification of glycerol by oleic acid and selective hydrogenation of oleic acid methylester, respectively.展开更多
The gas-phase dehydration of glycerol was conducted over HPW/MCM-41 catalysts,which were prepared by impregnation of different amount of H3PW(12)O(40)(HPW)on the MCM-41 support.The samples were characterized by ...The gas-phase dehydration of glycerol was conducted over HPW/MCM-41 catalysts,which were prepared by impregnation of different amount of H3PW(12)O(40)(HPW)on the MCM-41 support.The samples were characterized by XRD,N2 physisorption,FTIR,NH3-TPD,and pyridine-FTIR measurements.N2 physisorption results suggested that the uniform framework of MCM-41 could still be well maintained after modified with HPW.Pyridine-FTIR experiments indicate that HPW modified MCM-41 can generate rich Br?nsted acid sites.Moreover,Brnsted acid sites facilitated to improve acrolein selectivity.Under the optimized reaction conditions:40wt%HPW loading,20%glycerol concentration,and 320℃reaction temperature,the glycerol conversion and acrolein selectivity reach 85%and 80%,respectively.展开更多
文摘It was proved by ICP, fluorescence spectra and N 2 adsorption that the rare earth complex [C 5H 5NC 16H 33] [Eu(TTA) 4] is in the channel of Si-MCM-41 in the course of assembly. The rare earth complex of 67.9% is in the channel, suggesting that the assembly of the complex molecular on the mesoporous MCM-41 was carried out mainly in the channel.
文摘The composite mesoporous materials C2H5-MCM-41 are synthesized by multistep method,and its structure is characerized and evaluated.A solid-phase microextraction(SPME) method coupled to HPLC is proposed for the determination of trace pyrene with C2H5-MCM-41 mesporous materials as the coating of extractor.Extraction time,extraction temperation,stirring rate,ionic strength,and desorption time had been optimized.The liner range is 0.15~150μg·L-1,detection limit is 0.062μg.L-1(S/N=3),whereas the RSD(n=5) range is 0.035%,which suggests that the sample pretreatment method of SPME is fast,convenient,recise,sensitive and solvent-free.
文摘An efficient three-component synthesis of 3,4-dihydropyrimidinones using MCM-41 anchored sulfonic acid (MCM-41-R-SO3H) as a mild, heterogeneous catalyst for Biginelli reaction in CH3CN under reflux condition is described.
文摘The AlMCM-41 molecular sieves with two different pore sizes are hydrothermally synthesized in the presence of surfactants with two different chain lengths. H-AlMCM-41 and Ru-Sn-B/H-AlMCM-41 which are prepared by the conventional ion-exchange and incipient wetness techniques of the AlMCM-41 show fair catalytic activity for esterification of glycerol by oleic acid and selective hydrogenation of oleic acid methylester, respectively.
基金Funded by the National Natural Science Foundation of China(No.21303154)
文摘The gas-phase dehydration of glycerol was conducted over HPW/MCM-41 catalysts,which were prepared by impregnation of different amount of H3PW(12)O(40)(HPW)on the MCM-41 support.The samples were characterized by XRD,N2 physisorption,FTIR,NH3-TPD,and pyridine-FTIR measurements.N2 physisorption results suggested that the uniform framework of MCM-41 could still be well maintained after modified with HPW.Pyridine-FTIR experiments indicate that HPW modified MCM-41 can generate rich Br?nsted acid sites.Moreover,Brnsted acid sites facilitated to improve acrolein selectivity.Under the optimized reaction conditions:40wt%HPW loading,20%glycerol concentration,and 320℃reaction temperature,the glycerol conversion and acrolein selectivity reach 85%and 80%,respectively.