The present application discloses a method for preparing a hierarchical porous TS-1 molecular sieve comprising using a silicon-titanium ester polymer as both titanium source and silicon source. In the method, silicon and titanium are uniformly connected to a same polymer, and the hydrolysis rates thereof are equivalent during hydrolysis, which can prevent TiO.sub.2 precipitation and reduce the generation of non-framework titanium. Further, the silicon-titanium ester polymer is not only used as both silicon source and titanium source, but also can be used as a mesoporous template in the synthesis process. The obtained TS-1 molecular sieve has mesoporous structure with narrow pore size distribution.

The present application discloses a method for preparing hierarchical porous titanium-silicon TS-1 molecular sieve, wherein a titanate polyester polyol is used as titanium source. In the method, titanium is connected to a polymer, which makes titanium more difficult to hydrolyze, prevent the TiO.sub.2 precipitation and reduce the formation of non-framework titanium. In addition that such new type of the titanate polyester polyol acts as the titanium source during the synthesis process, the titanate polyester polyol can also be used as mesoporous template. Therefore, the TS-1 molecular sieve obtained by this method has mesoporous structure, which plays an important role in promoting the application of TS-1 molecular sieve in the field of catalysis.

The present invention relates to a process for the manufacture of a pulverulent, porous crystalline metal silicate, comprising the following steps: (a) hydrothermal synthesis employing an aqueous mixture comprising (A) a silicon source, (B) a metal source, and (C) an auxiliary component, yielding an aqueous suspension of reaction product 1, comprising a raw porous crystalline metal silicate; and (b) flame spray pyrolysis of reaction product 1, wherein the aqueous suspension obtained in step (a) is sprayed into a flame generated by combustion of a fuel in the presence of oxygen to form a pulverulent, porous crystalline metal silicate; wherein the aqueous suspension comprising reaction product 1 obtained in step (a) exhibits a solids content of ≤70% by weight; and wherein the effective peak temperature, T.sub.eff, experienced by at least 90% by weight of the porous crystalline metal silicate during flame pyrolysis, is in the range T.sub.min<T.sub.eff<T.sub.max, and wherein T.sub.min is 750° C., and wherein T.sub.max is 1250° C.

A method for the synthesis of siliceous or heteroatom-substituted MFI zeolites (M-MFI; M=Si, Ti, Nb, or Ta) with tunable densities of SiOH that depend simply on the ratio of hydrofluoric acid (HF) to structure-directing agent (SDA; tetrapropylammonium hydroxide) used within the synthesis gel. The equilibrated ion exchange between OH.sup.− and F.sup.− ions forms tetrapropylammonium fluoride in situ, which does not lead to the formation of SiOH defects within M-MFI. Comparisons of infrared spectra from 15 distinct M-MFI materials show that the densities of SiOH groups within M-MFI decrease linearly with the ratio of HF:SDA, independent of the identity of the heteroatom within the framework.

The present application discloses a method for preparing a hierarchical porous TS-1 molecular sieve, which uses a silicon-titanium ester polymer as both titanium source and silicon source. In the method, silicon and titanium are uniformly connected to a same polymer, and the hydrolysis rates thereof are equivalent during hydrolysis, which can prevent TiO.sub.2 precipitation and reduce the generation of non-framework titanium. Further, the silicon-titanium ester polymer is not only used as both silicon source and titanium source, but also can be used as mesoporous template in the synthesis process. The obtained TS-1 molecular sieve has mesoporous structure with narrow pore size distribution, which plays an important role in promoting the application of TS-1 molecular sieve in the field of catalysis.

An alkali metal ion modified titanium silicalite zeolite for gas phase epoxidation of propylene and hydrogen peroxide and a preparation method thereof. The method includes, at first step: preparing an alkali metal hydroxide modification solution; at second step: conducting controlled hydrothermal treatment on a TS-1 zeolite matrix by using an alkali metal hydroxide solution; and at third step: conducting post-treatment on the hydrothermally modified TS-1 zeolite, including solid-liquid separation, washing, drying and calcining. In the washing process, the modified TS-1 zeolite wet material is washed with a low concentration alkali metal hydroxide solution; alkali metal ions are reserved on the silicon hydroxyl of the modified titanium silicalite zeolite; and an infrared characteristic absorption band of a framework titanium active center modified by the alkali metal ions is in a range above 960 cm.sup.−1 and below 980 cm.sup.−1.

The present disclosure relates to a novel staged-synthesis method for introduction of various metals in the structure of zeolite frameworks by isomorphous substitution. This new method is based on a hydrothermal synthesis in which the metal addition to the precursor suspensions (gel) is delayed. This so-called “staged-synthesis method” allows to obtain nanosized silanol highly homo-geneous crystalline zeolite structures with a control of the metal location.

A tin-titanium-silicon molecular sieve, a preparation method and an application thereof are provided. The electron binding energy of framework tin active centers in the tin-titanium-silicon molecular sieve is 488.5 eV or less. In the tin-titanium-silicon molecular sieve, the molar ratio of titanium to silicon is preferably 0.005-0.03, and the molar ratio of tin to silicon is preferably 0.005-0.025. The tin-titanium-silicon molecular sieve of the invention has more catalytic active centers, a lower electron binding energy of framework tin active centers, and an excellent catalytic performance.

A novel synthetic crystalline molecular sieve material, designated boron SSZ-121 is provided. The boron SSZ-121 can be synthesized using 1,3-bis(1-adamantyl)imidazolium cations as a structure directing agent. The boron SSZ-121 may be used in organic compound conversion reactions and/or sorptive processes.

The present disclosure relates to a novel method for introducing various metals in the structure of zeolite frameworks by isomorphous substitution. This new method is based on a hydrothermal reaction of the metal with the zeolite. This method allows obtaining zeolite with a structure and with control of the metal location.