In the reaction of mathane, carbon dioxide with oxygen to synthesis gas, conversion ofCH4 was increased, but CO selectivity was reduced when CeO2 was added to Ni/CaO-Al2O3catalyst The characterization of TPR, XPS. XRD...In the reaction of mathane, carbon dioxide with oxygen to synthesis gas, conversion ofCH4 was increased, but CO selectivity was reduced when CeO2 was added to Ni/CaO-Al2O3catalyst The characterization of TPR, XPS. XRD and H2-TPD exhibited that, on one hand, theCeO2 promoter decreased the reduction temperature of catalyst. On the other hand, addition ofCeO2 resulted in an increase in the electron density of active component Ni, and as a result,reduced the ability of CH4 deep cracking and enhanced the resistance to carbon-deposition ofcatalyst. In addition, the existence of CeO2 was beneficial to decrease the Ni crystal particle size.展开更多
The effect of Al3+, NH, Na+ on the Ti content in the preparation of Ti-ZSM-5 by the isomorphous substitution of ZSM-5 using gaseous TiCl4 as titanium resource has been investigated. It is surprisingly found that altho...The effect of Al3+, NH, Na+ on the Ti content in the preparation of Ti-ZSM-5 by the isomorphous substitution of ZSM-5 using gaseous TiCl4 as titanium resource has been investigated. It is surprisingly found that although the direct ratio exists between the Ti content and the content of the skeletal Al: y=0.08x2+0.57x+1.23(here y represents TiO2% and x represents Al2O3%). but the catalytic activities of Ti-ZSM-5 for the oxidation of styrene sharply rise with the decrease of TiO2%. The skeletal Al hinders the Ti incorporation into the framework of molecular sieves characterized by FT-IR technique. At the same . NH ion has no effect on the Ti incorporation. but Na+ ion does.展开更多
A comparative study is made on the efficiencies of three initiators of Fe^(2+)-H_2O_2, K_2S_2O_8 and KMnO_4 in the grafting of acrylamide onto starch. Of the three initiators the best one is KMnO_4. Moreover, the kine...A comparative study is made on the efficiencies of three initiators of Fe^(2+)-H_2O_2, K_2S_2O_8 and KMnO_4 in the grafting of acrylamide onto starch. Of the three initiators the best one is KMnO_4. Moreover, the kinetic equation is also studied.展开更多
文摘In the reaction of mathane, carbon dioxide with oxygen to synthesis gas, conversion ofCH4 was increased, but CO selectivity was reduced when CeO2 was added to Ni/CaO-Al2O3catalyst The characterization of TPR, XPS. XRD and H2-TPD exhibited that, on one hand, theCeO2 promoter decreased the reduction temperature of catalyst. On the other hand, addition ofCeO2 resulted in an increase in the electron density of active component Ni, and as a result,reduced the ability of CH4 deep cracking and enhanced the resistance to carbon-deposition ofcatalyst. In addition, the existence of CeO2 was beneficial to decrease the Ni crystal particle size.
文摘The effect of Al3+, NH, Na+ on the Ti content in the preparation of Ti-ZSM-5 by the isomorphous substitution of ZSM-5 using gaseous TiCl4 as titanium resource has been investigated. It is surprisingly found that although the direct ratio exists between the Ti content and the content of the skeletal Al: y=0.08x2+0.57x+1.23(here y represents TiO2% and x represents Al2O3%). but the catalytic activities of Ti-ZSM-5 for the oxidation of styrene sharply rise with the decrease of TiO2%. The skeletal Al hinders the Ti incorporation into the framework of molecular sieves characterized by FT-IR technique. At the same . NH ion has no effect on the Ti incorporation. but Na+ ion does.
文摘A comparative study is made on the efficiencies of three initiators of Fe^(2+)-H_2O_2, K_2S_2O_8 and KMnO_4 in the grafting of acrylamide onto starch. Of the three initiators the best one is KMnO_4. Moreover, the kinetic equation is also studied.
