METHOD OF PRODUCING CRYSTALLINE ELEMENTOSILICATE OF PENTASIL ZEOLITE FAMILY AND CRYSTALLINE ELEMENTOSILICATE Russian patent published in 2024 - IPC C01B39/04 

FIELD: chemistry.

SUBSTANCE: invention relates to synthesis of zeolite structures which can be used in catalysis and sorption technologies. Disclosed is a method for synthesis of crystalline elementosilicate of the family of zeolites of pentasil of the MFI or BEA or MEL structural type, containing in the structure heteroatoms of elements (M) selected from Ti, Al, Sn, Zr, Hf, including the preparation of a precursor, characterized by a composition corresponding to the crystallisation region of the corresponding elementosilicate of the selected structural type. Finely dispersed silicon dioxide particles are homogenised in a solution containing a structure-forming agent (R) — tetraalkylammonium hydroxide, where alkyl is ethyl, propyl, or butyl, and a heteroatom source (M) selected from Ti, Al, Sn, Zr, Hf, followed by removal of excess water. Gel-like precursor is obtained with the following molar ratios of components: M:SiO₂=0.0025–0.06, R:SiO₂=0.1–0.6, H₂O:SiO₂=0.5–4.5. A mineralizing agent containing fluoride or hydroxide ion can be additionally added to the precursor. Prepared precursor is subjected to vapor-phase crystallisation in the absence of free water at 130–180 °C for 12–360 hours to form powdered elementosilicate, consisting of isolated crystals with size of 0.1–10.0 mcm. Immediately after crystallisation, steps of washing, drying and calcination are carried out. Obtained powder product can be subjected to granulation.

EFFECT: simplification of synthesis with reduction of consumption of reagents, increase of degree of use of initial reagents to 97%, wider range of methods for producing crystalline elementosilicates of pentasil structure, having high phase purity and developed microporosity, and wider range of metals-heteroatoms introduced into the pentasil framework as a result of direct synthesis.

11 cl, 3 dwg, 1 tbl, 42 ex