© 2010 Borealis AG A Generalized Modelling Tool for the Simulation of Molecular Species Transport and Thermodynamic Properties in Polymer Materials: Applications in Polyolefin Production and Downstream Processing Technology Vasileios Kanellopoulos, Shital Das, Mohammad Al-haj Ali and Sameer Vijay Process Development Group Borealis Polymers Oy, Porvoo – Finland Canadian Chemical Engineering Conference (October 2012, Vancouver, Canada)

© 2010 Borealis AG OUTLINE Borealis at a glance – Innovation Center Modeling of transport and thermodynamic properties during sorption/desorption processes Diffusion coefficient evaluation – free volume theory Thermodynamic calculations – SL-EOS Representative simulations Conclusions CSChE 2012 Vancouver

© 2010 Borealis AG Borealis at a Glance Leading provider of chemical and innovative plastics solutions that create value for society More than 50 years of experience Unique Borstar ® technology to develop polyolefin solutions that are tailored to customers’ needs Around 5,300 employees worldwide and customers in over 120 countries Ownership 64% IPIC / 36% OMV Joint venture in Middle East and Asia: Borouge (Abu Dhabi) CSChE 2012 Vancouver

© 2010 Borealis AG ‘Commodity’ path FeedstockOlefinsPolyolefinsConvertersEnd usersConsumers Reduce Recycle Recover ‘Value Creation’ path FeedstockOlefinsPolyolefinsConvertersEnd usersConsumers Reduce Recycle Recover Commitment to Value Creation through Innovation secures future growth CSChE 2012 Vancouver

© 2010 Borealis AG Introduction Olefin transport and thermodynamic properties in POs depends on: Type of penetrant Type of polymer Polymer morphology Crystallinity Crystal size distribution Operating Conditions (T, P) CSChE 2012 Vancouver

© 2010 Borealis AG Sorption & desorption process Unsteady-state diffusion takes place in a polymer film. The system is isothermal and isobaric, no reaction takes place. The penetrants diffusion coefficients are concentration dependent. Unsteady-state diffusion takes place in a polymer film. The system is isothermal and isobaric, no reaction takes place. The penetrants diffusion coefficients are concentration dependent CSChE 2012 Vancouver

© 2010 Borealis AG Model equations (Planar coordinates) Boundary Conditions Initial Condition At (Desorption) The sorption uptake,, is calculated as follows At CSChE 2012 Vancouver (Desorption) or

© 2010 Borealis AG Model equations (Spherical coordinates) Dimensionless Diffusion – Convection Unsteady State Equation Boundary Conditions Initial Condition At The sorption uptake,, is (Desorption) CSChE 2012 Vancouver (Desorption) or

© 2010 Borealis AG Diffusion coefficients: Shortcut methods Reduced sorption curves Diffusion Coefficient CSChE 2012 Vancouver

© 2010 Borealis AG A number of short methods have been used for the calculation of penetrant diffusion coefficients in polymers from sorption/desorption experiments Initial Slope Method Half Time Method Diffusion coefficients: Shortcuts methods CSChE 2012 Vancouver

© 2010 Borealis AG  = f(crystallinity, temperature, concentration, morphology) Diffusion through pores and polymer phase Diffusion through pores Diffusion through polymer phase 1. Diffusion through the pores 2. Diffusion through the amorphous polymer phase Diffusion Mechanisms Penetrant diffusion coefficient Polymer Phase Diffusion through polymer (ii) Diffusion through pores (i) Diffusion through polymer and pores (iii) CSChE 2012 Vancouver

© 2010 Borealis AG Diffusion coefficient (Free volume theory) The components in the system are envisioned to migrate by jumping into free-volume holes formed by natural fluctuations Diffusion of penetrants occurs only through the amorphous polymer phase The components in the system are envisioned to migrate by jumping into free-volume holes formed by natural fluctuations Diffusion of penetrants occurs only through the amorphous polymer phase CSChE 2012 Vancouver

© 2010 Borealis AG Diffusion coefficient (Free volume theory) γ i : is an overlap factor, 0.5  γi  1 D 0i : pre-exponential constant ω i : is the weight fraction of species “i” in the mixture V i * : is the specific critical hole free volume of species “i” The overall hole free-volume can be estimated (Ferry 1980): CSChE 2012 Vancouver

© 2010 Borealis AG The Sanchez-Lacombe EOS Binary interaction parameter CSChE 2012 Vancouver

© 2010 Borealis AG Ethylene in HDPE 1-butene in LLDPE-1-Butene The Sanchez-Lacombe EOS (Results) Solubility of a-olefins in semi-crystalline polyolefins. The theoretical predictions of the Sanchez-Lacombe EOS are in excellent agreement with the experimental data SL-EOS is capable of predicting higher a-olefin solubilities (i.e., C4-C8) in polyolefins CSChE 2012 Vancouver

© 2010 Borealis AG Representative simulations – Sorption (I) CSChE 2012 Vancouver

© 2010 Borealis AG Representative simulations – Sorption (II) CSChE 2012 Vancouver

© 2010 Borealis AG Representative simulations – Desorption CSChE 2012 Vancouver

© 2010 Borealis AG Conclusions A dynamic model to simulate the transport (both sorption and degassing) of penetrant(s) molecules in PO matrixes of various geometries (i.e., films, powders) developed This approach incorporates thermodynamic model for the calculation of penetrant’s solubility in semi-crystalline POs Aids in assessing the effect of particle morphology, size and operating conditions on mass transfer rate to and from polymer phase Used to describe POs downstream units (purge bin, steam dryers, stripping units) as well as optimizing design of process units and improve their operability CSChE 2012 Vancouver

© 2010 Borealis AG THANK YOU! Vasileios Kanellopoulos 17 th October 2012 The information contained herein is to our knowledge accurate and reliable as of the date of publication. Borealis extends no warranties and makes no representations as to the accuracy or completeness of the information contained herein, and assumes no responsibility regarding the consequences of its use or for any printing errors CSChE 2012 Vancouver

© 2010 Borealis AG Water for the World™ CSChE 2012 Vancouver