Reaction dynamics during the testing of polymerization catalyst

Document Type : Original research


HIPOL a.d., Gračački put b.b., Odžaci 25250, Serbia


The olefins 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 deactivation were estimated. The propylene solubility in a solvent mixture “heptane” was calculated using Soave-Redlich-Kwong equation of state. These data were then approximated by Henry-like equation and the results were verified in experiments. The influence of propylene dissolving in ”heptane which was examined in special experiments without catalyst has provided the independent estimation of gas-liquid mass transfer coefficient. It has been shown that the reaction rate during the first 20-30 min of test is much lower (or higher) than total monomer consumption, depending on reactant addition sequence. The method of kinetic experiments interpretation and corresponding mathematical model are proposed. The method enables to estimate the kinetic parameter of monomer dissolution, the reaction rate constant of polymerization, as well as the parameters of active centers transformation – activation, deactivation and self-regeneration. An adequacy of model was proved by the description of experiments at two different pressures but with the same parameters values.


Main Subjects

  1. Albizzati E, Cecchin G, Chadwick JC, Collina G, Giannini U, Morini G, Noristi L (2005) Ziegler- Natta catalysts and polymerizations. In: Polypropylene handbook, Hanser, Munich, 15- 106
  2. Nagel EJ, Kirillov VA, Ray WH (1980) Prediction of molecular weight distributions for high density polyolefins. Ind Eng Chem Prod Des Dev 19: 372-379
  3. Bukatov GD, Zaikovskii VI, Zakharov VA, Kryukova GN, Fenelonov VB, Zagrafskaya RV (1982) Morphology of polypropylene granules and its relation with texture of titanium trichloride. Vysokomol Soedin 24: 542-548
  4. McKenna TF, Soares JBP (2001) Single particle modeling for olefin polymerization on supported catalysts: A review and proposals for future developments. Chem Eng Sci 56: 3931- 3949
  5. Najafi M, Parvazinia M, Ghoreishy HR, Kiparissides C (2014) Development of a 2D single particle model to analyze the effect of initial particle shape and breakage in olefin polymerization. Macromol React Eng 8: 29-45
  6. Ostrovskii NM, Kenig F (2005) About mechanism and model of deactivation of Ziegler–Natta polymerization catalysts. Chem Eng J 107: 73-77
  7. Floyd S, Choi KY, Taylor TW, Ray WH (1986) Polymerization of olefins through heterogeneous catalysis.III. Polymer particle modelling with an analysis of intraparticle heat and mass transfer effects. J Appl Polym Sci 32: 2935-2960
  8. Debling JA, Ray WH (1995) Heat and mass transfer effects in multistage polymerization process: Impact polypropylene. Ind Eng Chem Res 34: 3466-3480
  9. Ostrovskii NM, Stoiljkovic D (2011) Evaluation of the effect of reaction and mass transfer on the growth of polymer particles in olefins polymerization. Theor Found Chem Eng 45: 40- 52
  10. Kyoung-Su Ha, Kee-Youn Yoo, Hyun-Ku Rhee (2001) Modeling and analysis of a slurry reactor system for heterogeneous olefin polymerization: The effects of hydrogen concentration and initial catalyst size, J Appl Polym Sci 79: 2480-2493
  11. Jin-San Yoon, Ray WH (1987) Simple mechanistic model for the kinetics and catalyst activity decay of propylene polymerization over TiCl3 catalyst with DEAC cocatalyst. Ind Eng Chem Res 26: 415-422
  12. Magni E, Malizija F, Somorjai GA (1998) Surface science toward single site heterogeneous polypropylene catalysis. In: Polypropylene – Past, present and future: The challenge continues. Ferrara, Italia, 179-203
  13. Dumas C, Hsu CC (1989) Propylene polymerization in a semibatch slurry reactor over supported TiCl4/MgCl2/Ethyl Bensoate/ Triethyl Aluminium catalyst. I. Catalytic behaviour. J Appl Polym Sci 37: 1605-1623
  14. Ochoteco E, Vecino M, Montes M, de la Cal JC (2001) Kinetics and properties in metallocene catalysed propene polymerizations. Chem Eng Sci 56: 4169-4179
  15. Reid RC, Prausnitz JM, Sherwood TK (1977) The properties of gases and liquids. McGrow-Hill
  16. Natta G (1959) Kinetic studies of a-olefin polymerization. J Polym Sci 34: 21-48
  17. Zakharov VA, Bukatov GD, Yermakov YI (1983) On the mechanism of olefin polymerization by Ziegler-Natta catalysts. Adv Polym Sci 51: 61- 100
  18. Keii T (2004) The theory of Ziegler-Natta- Kaminsky polymerization. Kodansha, Springer
  19. Keii T (1986) Mechanistic studies on Ziegler- Natta catalysis: A methodological reconsideration. In: Catalytic polymerization of olefins. Elsevier, Amsterdam, 1-27
  20. Lim SY, Choung SJ (1997) Studies on the catalytic deactivation in propylene polymerization. Appl Catal A: General 153: 103-118
  21. Ostrovskii NM, Fekete L (2014) Process dynamics in slurry polymerization. In: Proceeding of the 12th international conference of physical chemistry, Belgrade, Serbia, 207–214
  22. Dompazis G, Kanellopoulos V, Kiparissides C (2005) A multi-scale modeling approach for the prediction of molecular and morphological properties in multi-site catalyst, olefin polymerization reactors. Macromol Mater Eng 290: 525-536
  23. Liu X (2007) Modeling and simulation of heterogeneous catalyzed propylene polymerization. Chinese J Chem Eng 15: 545-553