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Heteroatoms of Al and Ti are effectively introduced into the framework of ordered mesoporous silica materials (designated as MAS-7 and MTS-9, respectively) in strong acidic media (pH < 0) by a two-step procedure. MAS-7 shows high catalytic activities for the cracking of both small (cumene) and bulky (1,3,5-triisopropylbenzene) molecules because it combines the advantages of both zeolites (strong acidity) and mesoporous materials (large pores). In contrast, Al-SBA-15 samples prepared from both "post-synthesis" and "direct synthesis" present much lower catalytic activities than MAS-7. Furthermore, MTS-9 exhibits very high catalytic activity in phenol hydroxylation by H 2 O 2 , giving the phenol conversion of 26%, comparable to TS-1.

A simple and effective method denoted "pH-adjusting" is used to graft a large amount of heteroatoms such as Al and Ti to mesoporous silica material SBA-15. The products prepared by this method show highly ordered mesostructures with large surface areas and uniform mesopore size distribution. The results of ICP, EDX, 27 Al NMR, calcium ion-exchange capacity, and UV-vis spectra show that almost all the heteroatoms added into the initial reaction mixture can be introduced into the products, and moreover, the heteroatoms introduced by this route locate at mainly tetrahedrally coordinated sites. CM0343857 492

Mesoporous titanosilicates (MTS-9) are successfully prepared in strong acidic media by a two-step synthesis. MTS-9 has an ordered hexagonal structure and exhibits superior hydrothermal stability and high catalytic activity for the oxidation of the small molecules of phenol and styrene and also of the bulky molecule of trimethylphenol.

Mesoporous aluminosilicates (MAS-9) with ordered hexagonal struture have been prepared by assembly of preformed aluminosilicate precursors with a triblock copolymer in strongly acidic media by a two-step procedure. MAS-9 exhibits extraordinarily good hydrothermal stability and high catalytic activities for the cracking of both cumene and 1,3,5-triisopropylbenzene. Even after treatment in boiling water for 120 h, MAS-9 continues to show a large surface area (680 m 2 /g) and high catalytic activities. Furthermore, this two-step strategy could be used as a new general method for the preparation of mesoporous aluminosilicate materials under strongly acidic conditions.

Highly ordered mesoporous silica materials are hydrothermally synthesized at high temperature by using fluorocarbon–hydrocarbon surfactant mixtures as templates. Because of the high temperature of the synthesis, the obtained materials show complete silica condensation, which give rise to ultra‐stabile structures. JLU‐20 for example (see TEM image of calcined JLU‐20) has a fully condensed mesopore wall with a very high Q4/Q3 ratio of 6.5.

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Novel mesostructured titanosilicates designated as MTS-9 have been successfully synthesized from assembly of preformed nanosized titanosilicate precursors with polymer surfactants. Mesoporous MTS-9 shows highly hydrothermal stability in boiling water (over 120 h) as compared with that of Ti−MCM-41 and SBA-15. In phenol hydroxylation, Ti−MCM-41 shows very low catalytic activity (2.5%), but MTS-9 exhibits very high catalytic activity, with phenol conversion of 26%, which is comparable with TS-1. In styrene epoxidation, MTS-9 shows high activity and selectivity similar to those of TS-1, which are much different from those of Ti−MCM-41. In 2,3,6-trimethylphenol hydroxylation, Ti−MCM-41 is inactive because of the relatively low oxidation ability of Ti species in the amorphous wall of Ti−MCM-41, and TS-1 is also inactive because of the inaccessibility of the small micropores of TS-1 to the large diameter of a bulky molecule like 2,3,6-trimethylphenol. However, MTS-9 is very active for this reaction with conversion of 18.8% indicating that MTS-9 is an effective catalyst for the oxidation of bulky molecules. The MTS-9 samples were characterized with infrared, UV−visible, UV−Raman, and numerous other techniques. The results suggest that the titanium species in MTS-9 are TS-1-like, and that the pore walls of MTS-9 contains primary and secondary structural building units, similar to those of microporous zeolites. Such unique structural features might be responsible for the observed strong oxidation ability and high hydrothermal stability of the mesostructured titanosilicates. Heating MTS-9 at 500 °C leads to the transformation of titanium species, giving relatively low catalytic conversion in phenol hydroxylation, which suggests that increasing thermal stability of titanium sites like TS-1 species in the mesoporous wall is still a great task for preparation of mesostructured titanosilicates.