Mesoporous aluminosilicates with cubic and hexagonal structure have been synthesized by structure units of β zeolite in a two step crystallization process and characterized by XRD, IR, N 2 physical adsorption and des...Mesoporous aluminosilicates with cubic and hexagonal structure have been synthesized by structure units of β zeolite in a two step crystallization process and characterized by XRD, IR, N 2 physical adsorption and desorption, 27 Al MAS NMR and NH 3 TPD techniques. The results show that MB48(25) and MB41(25) were similar to MCM 48 and MCM 41 on the long range structure respectively and MB48 with a cubic structure can be synthesized under the condition of a lower n (CTMAB)/ n (SiO 2) ratio. HMB48(25) and HMB41(25) exhibit a stronger acidic strength than conventional HMCM 41. The catalytic activity of HMB48(25) was the highest for cumene cracking and alkylation of 2,4 tert butylphenol with tert butylalcohol.展开更多
Highly pure crystalline MCM 22 was synthesized under the conditions of a high temperature, low content of Na and water in a short time without addition of the crystal seeds of MCM 22. MoO 3 supported by H MCM 22 as th...Highly pure crystalline MCM 22 was synthesized under the conditions of a high temperature, low content of Na and water in a short time without addition of the crystal seeds of MCM 22. MoO 3 supported by H MCM 22 as the catalyst of the reactions of non oxidative aromatization of methane is investigated and it is evident that MCM 22 is a promising catalyst support for the studied methane aromatization reaction.展开更多
MCM 56, a novel layered zeolite, has been synthesized under a stirring condition by hydrothermal method and characterized by XRD, TEM, TG and DTA. TEM shows that most of the crystals exist in the form of single layer....MCM 56, a novel layered zeolite, has been synthesized under a stirring condition by hydrothermal method and characterized by XRD, TEM, TG and DTA. TEM shows that most of the crystals exist in the form of single layer. Based on the experimental facts and framework type which MCM 56 belongs to, MCM 56 should consist of very thin MWW type layers which are just one unit cell along the c direction, and have a unique architecture with two dimensional 10 MR pore system inside the layer and 12 MR cups(half of the MWW cages described in the MCM 22 or MCM 49) on the crystal exterior without cages between layers.展开更多
MoO3/MCM-49 has been synthesized under the special condition and it shows a high activity and selectivity for nonoxidative aromatization of methane with a long lifetime and extreme capacity of anti-coking. MoO3/MCM-49...MoO3/MCM-49 has been synthesized under the special condition and it shows a high activity and selectivity for nonoxidative aromatization of methane with a long lifetime and extreme capacity of anti-coking. MoO3/MCM-49 is considered as a very promising catalyst for the title reaction.展开更多
文摘Mesoporous aluminosilicates with cubic and hexagonal structure have been synthesized by structure units of β zeolite in a two step crystallization process and characterized by XRD, IR, N 2 physical adsorption and desorption, 27 Al MAS NMR and NH 3 TPD techniques. The results show that MB48(25) and MB41(25) were similar to MCM 48 and MCM 41 on the long range structure respectively and MB48 with a cubic structure can be synthesized under the condition of a lower n (CTMAB)/ n (SiO 2) ratio. HMB48(25) and HMB41(25) exhibit a stronger acidic strength than conventional HMCM 41. The catalytic activity of HMB48(25) was the highest for cumene cracking and alkylation of 2,4 tert butylphenol with tert butylalcohol.
文摘Highly pure crystalline MCM 22 was synthesized under the conditions of a high temperature, low content of Na and water in a short time without addition of the crystal seeds of MCM 22. MoO 3 supported by H MCM 22 as the catalyst of the reactions of non oxidative aromatization of methane is investigated and it is evident that MCM 22 is a promising catalyst support for the studied methane aromatization reaction.
文摘MCM 56, a novel layered zeolite, has been synthesized under a stirring condition by hydrothermal method and characterized by XRD, TEM, TG and DTA. TEM shows that most of the crystals exist in the form of single layer. Based on the experimental facts and framework type which MCM 56 belongs to, MCM 56 should consist of very thin MWW type layers which are just one unit cell along the c direction, and have a unique architecture with two dimensional 10 MR pore system inside the layer and 12 MR cups(half of the MWW cages described in the MCM 22 or MCM 49) on the crystal exterior without cages between layers.
文摘MoO3/MCM-49 has been synthesized under the special condition and it shows a high activity and selectivity for nonoxidative aromatization of methane with a long lifetime and extreme capacity of anti-coking. MoO3/MCM-49 is considered as a very promising catalyst for the title reaction.
