Reaction dynamics during the testing ofpolymerization catalyst

The olefns polymerization process in a slurry reactor is discussed. The reaction rate dynamics was analyzed and the contributions of feed flow, gas-liquid mass transfer, polymerization reaction, and catalyst deactivationwere estimated. The propylene solubility in a solvent mixture heptane was calculated using Soave-RedlichKwong equation of state. These data were then approximated by Henry-like equation and the results were verifed inexperiments. The influence of propylene dissolving in heptane which was examined in special experiments withoutcatalyst has provided the independent estimation of gas-liquid mass transfer coeffcient. It has been shown that thereaction rate during the frst 20-30 min of test is much lower (or higher) than total monomer consumption, dependingon reactant addition sequence. The method of kinetic experiments interpretation and corresponding mathematicalmodel are proposed. The method enables to estimate the kinetic parameter of monomer dissolution, the reaction rateconstant of polymerization, as well as the parameters of active centers transformation – activation, deactivation andself-regeneration. An adequacy of model was proved by the description of experiments at two different pressures butwith the same parameters values. Polyolefns J (2015) 2: 89-97

Keywords:

reaction dynamics , propylene polymerization , catalyst testing