The composite,prepared with polypropylene grafting maleic anhydride and silica crosslinked by 3 aminopropyltriethyoxysilane,was used as the carrier to support titanium chloride.XPS and FTIR measurements were emplyed t...The composite,prepared with polypropylene grafting maleic anhydride and silica crosslinked by 3 aminopropyltriethyoxysilane,was used as the carrier to support titanium chloride.XPS and FTIR measurements were emplyed to investigate the states of several atoms during stepwise supporting catalyst for clarifying the mechanism.The results showed two possible mechanisms of active catalytic sites on the composite carrier:the catalytic sites bridged through MAO on the inorganic silica gel;on contrary,the catalytic sites bridging with carbonyls of amide formed in the composite.展开更多
A nanosolid heteropoly acid of H 3PW 12 O 40 /SiO 2 was prepared with the sol-gel method and used to catalyze sythesis of methyl 5-amino-1,2,4,-trazolylformate sulfate.The structure of the nanosolid heteropoly acid H ...A nanosolid heteropoly acid of H 3PW 12 O 40 /SiO 2 was prepared with the sol-gel method and used to catalyze sythesis of methyl 5-amino-1,2,4,-trazolylformate sulfate.The structure of the nanosolid heteropoly acid H 3PW 12 O 40 /SiO 2 was characterized by IR,XRD and TEM.The following optimum condition were that the mole ratio of alcohol to carboxylic acid is 27∶1,the temperature is 75℃,the reaction time is 5 hours,and the catalyst is 2 5% of feedstock.Under the optimum conditions,the yield of esters was above 94%.展开更多
基金supported by the National Natural Science Foundation of China(21377018)the Natural Science Foundation of Liaoning Province of China(2013020116)the Fundamental Research Funds for the Central Universities(DUT15ZD240)~~
文摘The composite,prepared with polypropylene grafting maleic anhydride and silica crosslinked by 3 aminopropyltriethyoxysilane,was used as the carrier to support titanium chloride.XPS and FTIR measurements were emplyed to investigate the states of several atoms during stepwise supporting catalyst for clarifying the mechanism.The results showed two possible mechanisms of active catalytic sites on the composite carrier:the catalytic sites bridged through MAO on the inorganic silica gel;on contrary,the catalytic sites bridging with carbonyls of amide formed in the composite.
文摘A nanosolid heteropoly acid of H 3PW 12 O 40 /SiO 2 was prepared with the sol-gel method and used to catalyze sythesis of methyl 5-amino-1,2,4,-trazolylformate sulfate.The structure of the nanosolid heteropoly acid H 3PW 12 O 40 /SiO 2 was characterized by IR,XRD and TEM.The following optimum condition were that the mole ratio of alcohol to carboxylic acid is 27∶1,the temperature is 75℃,the reaction time is 5 hours,and the catalyst is 2 5% of feedstock.Under the optimum conditions,the yield of esters was above 94%.
