METHOD OF PREPARING CATALYST AND A METHOD FOR ISOMERIZATION OF PARAFFINIC C-C-HYDROCARBONS Russian patent published in 2004 - IPC

FIELD: petrochemical process catalysts.

SUBSTANCE: invention relates to processes and catalysts of medium-temperature isomerization of hydrocarbons and provides a method for preparing mordenite-containing catalyst by mixing mordenite in hydrogen or ammonium form, characterized by SiO₂/Al₂O₃ ratio 14-23, with inorganic binder, one or several hydrohalic acids and their ammonium salts (per 1 part mordenite: 0.11-0.66 parts binder and 0.003-0.15 parts hydrohalic acid(s) or their ammonium salt(s) on conversion to weight of halide). Resulting mixture is granulated, granules are dried and subjected to 2 heat treatments: in dried air or nitrogen containing less than 300 vol ppm moisture at 400-600^оС and then in steam-air mixture or flue gas at 250-500^оС). Thermally treated granules are impregnated with solution of precious metal compound in amounts required to provide 0.1-1.% of metal in catalyst in presence of aqueous hydrochloric acid or hydrofluoric acid in amounts 0.3 to 5% on the weight of granulated carrier (calculated on conversion to halogene), while ratio of the volume of impregnating solution to the weight of carrier equals 0.4-0.9 L/kg. Dried catalyst is calcined in dry air flow at 400-550^оС. Aforesaid binder is selected from: alumina, clay, silica gel, and diatomic earths or their mixtures with alumina. Thus prepared catalyst is used in isomerization of C₄-C₇-hydrocarbons in presence of hydrogen at 180-300^оС, pressure 1-5 MPa, hydrogen/hydrocarbon ratio (0.5-4):1, and volumetric flow rate of raw material 0.5 to 4 h^-1.

EFFECT: increased degree of isomerization and selectivity of process.

11 cl, 1 tbl, 21 ex