PROCESSES FOR MAKING CATALYST COMPOSITIONS HAVING IMPROVED FLOWABILITY Russian patent published in 2018 - IPC B01J37/00 B01J37/04 C08F2/00 C08F10/00 

FIELD: chemistry.

SUBSTANCE: invention relates to a process for the preparation of a catalyst composition and to a polymerisation process for the production of an ethylene polymer or copolymer in which a catalyst composition prepared by the process is used. Process for preparing a catalyst composition comprises: mixing at a controlled temperature of 30°C to 90°C, a carboxylate metal salt containing free carboxylic acids, with a first organic solvent having a dielectric constant at 25°C, greater than or equal to 3.0, where the first organic solvent does not contain methanol, extracting the free carboxylic acids from the carboxylate metal salt obtained in the mixing step at a controlled temperature, washing the carboxylate metal salt obtained at the extraction step, at a controlled temperature, with a second organic solvent having a dielectric constant at 25°C, greater than or equal to 3.0, where the second organic solvent does not contain methanol; drying the carboxylate metal salt obtained at the washing step to obtain a dried carboxylate metal salt, where the dried carboxylate metal salt is substantially free of carboxylic acids, as determined by differential scanning calorimetry, so that the dried carboxylate metal salt does not exhibit any melting peaks that are located at a temperature less than or equal to 75°C, combining the dried carboxylate metal salt with a catalyst, which is a metallocene catalyst compound containing a titanium, zirconium or hafnium atom to form a catalyst composition.

EFFECT: resulting catalyst composition has improved flowability and is capable of continuously operating during polymerisation.

10 cl, 4 dwg, 1 tbl, 17 ex