مرکز منطقه ای اطلاع رساني علوم و فناوري -

چكيده لاتين :

The gas phase polymerization of butadiene on new heterogenized bifunctional cobalt-containing catalytic dithiosystems was studied. Earlier, some highly active and efficient homogeneous bifunctional catalyst-stabilizers were developed on the bases of Ni- and Co-dithioderivatives (such as O,O-disubstituted dithiophosphates and N,N-dithiocarbamates) in combination with aluminium organics (such as dialkylaluminiumchlorides, alkylaluminium-dichlorides, and aluminoxanes) for butadiene solution polymerization and simultaneous stabilization of end polymer. The problem of separating homogeneous catalysts from the reaction medium is still the most important obstacle in blocking its large scale applications in industry. A number of potential methods for homogeneous catalyst separation and recovery have been or are presently being developed, such as a two-phase catalysis and heterogenization on inorganic or organic supports. Cobalt-containing bifunctional catalytic dithiosystems have been heterogenized on various supports (such as silica gels, aluminium oxides, zeolites, carbon black, etc.) by direct deposition or pre-alumination methods. The obtained data demonstrate that the pre-alumination method of immobilization of bifunctional cobalt-containing catalytic dithiosystems shows very high activity in gas phase polymerization of butadiene. These catalystsי productivity reaches -650.02200.0 kg PBD/g Co.h, which is much higher than the output of solution process using the same homogeneous catalysts (57.0 kg PBD/g Co.h) and the known gas phase process using the heterogenized neodymium-catalysts (500.0 kg PBD/g Nd.h). High activities of heterogenized bifunctional cobalt-containing catalytic dithiosystems allow the development of principally a new ecologically favourable and economically feasible technology of butadiene gas phase polymerization process by involving them as raw materials not only for pure butadiene, but also butadiene as C4 fraction of pyrolysis product.