Highly effective formation of cyclopentanol through the liquid-phase hydration of cyclopentene has been attempted on various zeolites catalysts. MCM-22 zeolite was the most selective catalyst, which actively converted cyclopentene to cyclopentanol with a selectivity up to 99%. The effects on the hydration of catalyst preparation method, reaction atmosphere and temperature have been investigated for the MCM-22 catalysts. On the basis of the effect of reaction atmosphere, the mechanism of liquid-phase cyclopentene hydration was proposed. The thermodynamic equilibrium between cyclopentene and cyclopentanol was suggested to control greatly the cyclopentene conversion. The cyclopentene conversion was increased to 10% by increasing the water/cyclopentene ratio. Poisoning using organic amines with different molecular sizes revealed that the hydration occurred mainly in the 10-membered ring channels of MWW structure, which had an elliptic aperture smaller than that of MFI structure, exhibiting a significant shape selectivity by suppressing the etherification cyclopentanol.

A series of mesoporous molecular sieves with various SiO2/Al2O3 ratios have been applied to the liquid-phase Beckmann rearrangement of cyclohexanone oxime. The influences of solvent, aluminum content, aluminum-incorporating method, and catalyst structure on the catalytic performance have been investigated. Benzonitrile has been found to be a suitable solvent. The surface silanol groups ineffectively catalyze the rearrangement, whereas the acid sites generated by incorporation of aluminum improve the activity and the selectivity to ε-caprolactam remarkably. Moreover, an Al-containing MCM-41 catalyst prepared by the postsynthetic method using AlCl3 as an aluminum precursor exhibits higher lactam selectivity than a directly synthesized one. For a given aluminum content, MCM-41 shows superior performance to beta zeolite and other mesoporous catalysts, SBA-1 and SBA-15. It has been suggested that a sufficient amount of acid sites with appropriate strength is of importance to the liquid-phase Beckmann rearrangement.

Al- and Ga-incorporated ETS-10, designated as ETAlS-10 and ETGaS-10, respectively, were synthesized by using P25 titania as a Ti source. The isomorphous substitution of Al and Ga for framework Si at the (4Si) environment was confirmed by 29Si MASNMR measurements. ETS-10 was more active in the Knoevenagel condensation than Y-type zeolites. The introduction of Al and Ga into ETS-10 enhanced the activity, due to the increase of the ion-exchange sites, which act as Br

A new titanosilicate, named Del-Ti-MWW, has been prepared by delaminating the lamellar precursor of Ti-MWW, which is postsynthesized from highly deboronated MWW zeolite with the assistance of cyclic amine. The amount of organic base used for supporting surfactant in swelling the layered structure should be controlled carefully to delaminate efficiently without the collapse of the structure. Ultrasound treatment is demonstrated to delaminate the swollen material more completely. Del-Ti-MWW materials have a large surface area, which mitigates effectively the steric restrictions imposed by conventional microporous titanosilicates to bulky molecules. Del-Ti-MWW, maintaining the fundamental structure of MWW zeolite and tetrahedral Ti species in the framework position, proves to be superior to TS-1, Ti-Beta, three-dimensional Ti-MWW and even mesoporous Ti-MCM-41 in the epoxidation of a wide range of bulky alkenes with hydrogen peroxide.

Mesoporous Ti-SBA-15 has been postsynthesized by the titanation of pure silica SBA-15 in glycerol with the assistance of quaternary organic ammonium hydroxides, and has been extensively characterized by various techniques to investigate the mesostructural and catalytic properties, and the chemical nature of the incorporated Ti species, in comparison with those of Ti-MCM-41. To incorporate tetrahedral Ti species into the silica walls of SAB-15, the titanation needs to be carried out at elevated temperature and using an optimum amount of organic ammonium hydroxide. Ti-SBA-15 samples with a Si/Ti ratio ranging from 376 to 16 are successfully prepared with the retention of hexagonal mesostructure by elaborately conducting the titanation. The nature of the Ti species depends greatly on the Ti loading. At Si/Ti ratios higher than 50, the Ti species are mainly tetrahedrally coordinated in isolated states, while poorly dispersed Ti species of octahedral coordination are formed at higher Ti incorporation levels; however, no anatase phase is formed in all cases. The IR band at 948cm-1 due to Si-O-Ti bonds can be used to characterize the tetrahedral Ti species in mesoporous materials, but the techniques of dehydration or trimethylsilylation should be adopted to get rid of the influence of silanol groups. In an actual catalytic reaction, Ti-SBA-15 exhibits not only extremely high thermal stability but also outstanding endurance against Ti leaching not observed for Ti-MCM-41. Ti-SBA-15 is thus presumed to be a promising liquid-phase oxidation catalyst.