| Mesoporous molecular sieves have potential application in the areas of adsorption, catalysis and petrochemical industry due to their unique pore structure and high specific surface area. The application of the pure silica mesoporous molecular sieve was limited in adsorption, catalysis and petrochemical industry because it possesses some disadvantages such as a neutral framework, the poor thermal and hydrothermal stabilities, low catalytic activity and weak surface acidity. The modification of mesoporous molecular sieve can be performed by the incorporation of metal atom into the silica framework, which can change its acidity and improve its acidic sites amount. Mesoporous molecular sieve exhibits different performances owing to the introduction of different metal atoms into the mesoporous wall. Therefore, the modification by the doping of metal atom into mesoporous wall has attracted considerable attention among researchers.This study reviewed the discovery and history of mesoporous molecular sieve and its structure characteristic was also described. The author concluded its essential function and synthetic method. In particular, some discussions in synthesis, characterization, modification, improvement of stability and application were carried out. Zr (or Co, Ni, Fe, Ce) containing mesoporous molecular sieves were prepared by different methods. The effect of several factors including crystallization temperature, crystallization time and proportion of the raw materials on the textural property of mesoporous molecular sieve was investigated in detail. The resulting mesoporous molecular sieves were characterized by means of XRD, N2 physical adsorption, TEM, Raman, TG-DSC, FT-IR, XPS, 29SiMAS-NMR and NH3-TPD, respectively. The catalytic performances of these mesoporous molecular sieves were also evaluated. The Zr-MCM-41 mesoporous molecular sieves with different zirconium contents were synthesized by hydrothermal method and microwave irradiation method, respectively. The results showed that the specific surface area and pore volume of the samples gradually decreased, and the mesoporous ordering gradually deteriorated with the increase of Zr doping contents, the rise of calcination temperature and the prolonging of the hydrothermal treatment time, respectively. The Zr-MCM-41 sample has good thermal and hydrothermal stabilities. The mesoporous framework of the Zr-MCM-41 sample still maintained after calcination at 750℃for 4h or hydrothermal treatment at 100℃for 6d. The Zr-MCM-41 mesoporous molecular sieve can be synthesized successfully when the molar ratio of ZrO2/SiO2 is less than 0.3. Compared with the hydrothermal method, the Zr-MCM-41 mesoporous molecular sieves obtained by microwave method need short crystallization time and less energy source, and the microwave irradiation method has some advantages such as easy to perform, even heat and environmentally friendly.The Zr-incorporated MCM-48 mesoporous molecular sieves with long range ordering were successfully synthesized by hydrothermal method with the aid of fluoride ions. The results displayed that the zirconium atom was introduced into the silica framework of MCM-48. The textural property and structural regularity of the resulting Zr-MCM-48 mesoporous molecular sieve were strongly affected by crystallization temperature, crystallization time, n (F-)/n (Si) and the molar ratio of Zr/Si. The addition of proper NaF is favorable for the formation of the cubic framework of Zr-MCM-48; the addition of excessive NaF will result in the decrease in the mesoporous ordering. The optimum synthesis condition of cubic Zr-MCM-48: crystallization temperature is 120℃, crystallization time is 24h and the molar ratio of n(F-)/n(Si) is 0.1. After calcination at 800℃for 4h or hydrothermal treatment at 100℃for 24h, the Zr-MCM-48 mesoporous molecular sieve still retained mesoporous framework. The Zr-MCM-48 sample exhibited good thermal and hydrothermal stabilities.SO42-/Zr-MCM-41 and SO42-/Zr-MCM-48 solid acid catalysts were prepared by wet impregnation with H2SO4 solution and the obtained SO42-/Zr-MCM-41 and SO42-/Zr-MCM-48 solid acid catalysts still maintained the mesoporous structure. The acid amount analysis results showed that the amount of strong acid sites of the O42-/Zr-MCM-48 sample is evidently more than that of the SO427Zr-MCM-41 sample. Under the same reaction condition, the SO42/Zr-mcm-48 catalyst exhibited high conversion of phenol and the selectivity to 2,4-DTBP as compared with the SO42-/Zr-MCM-41 catalyst due to its unque cubic arrangement of three-dimensional interwoven structure. When the molar ratio of tert-butanol/phenol is 2 and WHSV is 2h-, a maximum phenol conversion of 91.6%was achieved at the reaction temperature of 140℃.Ni (or Co, Fe)-incorporated (loading) MCM-41 mesoporous molecular sieves were prepared by hydrothermal method or impregnation method. The multi-wall carbon nanotubes (MWCNTs) with high quality were prepared by chemical vapor deposition (CVD) method using the as-prepared mesoporous molecular sieves as catalyst via pyrolysis of ethanol. The pyrolysis temperature is different in preparation process of carbon nanotubes using different catalysts catalyzed pyrolysis of ethanol. The optimum ethanol pyrolysis temperature of MWCNTs obtained by using Fe-loading MCM-41 as catalyst is 800℃; the optimum ethanol pyrolysis temperature of MWCNTs obtained over Co-incorporated (loading) MCM-41 catalyst is 750℃; the optimum ethanol pyrolysis temperature of MWCNTs obtained utilizing Ni-incorporated (loading) MCM-41 as catalyst is 700℃. The MWCNTs obtained over metal loading MCM-41 catalyst have uneven diameter and poor quality. The MWCNTs obtained over Ni (or Co)-incorporated MCM-41 catalyst has high quality.The Ce-MCM-41 mesoporous molecular sieves with different cerium contents were synthesized by microwave irradiation method and room temperature condition, respectively. The template was efficiently removed after calcination at 550℃for l0h. The mesoporous ordering of Ce-MCM-41 sample was influenced by the different molar ratio of n(Si)/n(Ce). The specific surface area and pore volume decrease as the cerium content increased, and the ordering deteriorated. On the contrary, pore size increased. Under the same raw materials proportion, the cerium content of Ce-MCM-41 sample synthesized by microwave method is higher than that of the Ce-MCM-41 sample obtained under room temperature, and the mesoporous ordering also decreased.
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