| 摘要 |
Method for producing a purified C5 fraction (A), enriched in isoprene (I) and suitable for selective catalytic polymerization of (I), starting from an initial C5 fraction (B) from a fluidized-bed catalytic cracker. Method for producing a purified C5 fraction (A), enriched in isoprene (I) and suitable for selective catalytic polymerization of (I), starting from an initial C5 fraction (B) from a fluidized-bed catalytic cracker. The method comprises subjecting an intermediate C5 fraction (C), containing less than 30 wt.% methylbutenes (II) and derived from (B), to a dehydrogenation reaction, and purifying the product to produce (A), practically free of disubstituted alkynes, 'real' alkynes and cyclopentadiene. The catalyst for polymerization of (I) comprises a conjugated diene; a rare earth metal salt (X) of an organophosphoric acid, suspended in an inert, saturated hydrocarbon solvent; an alkylating agent (Y; trialkylaluminum or dialkylaluminum hydride) with mole ratio (Y):(X) 1-5; and an alkylaluminum halide (Z) as halogen donor. An Independent claim is also included for a method for producing an isoprene homopolymer (HP) with content of cis-1,4 chains at least 98%, by using the specified catalyst system.
|
