Laboratory for Chemical Technology, Ghent University Experimental and kinetic study of the Transesterification of Ethyl acetate and Methanol over Gel and Macroporous acidic ion – exchange resins Evelien Van de Steene 1

Transesterification 2 Transesterification: Biodiesel production Transesterification: Model reaction PhD symposium, Ghent, 5 th December 2012

Ion exchange resin as catalyst 3 Ecofriendly Noncorrosive Reusable 3 Gel-type resins (K1221) Macroporous resins (K2629, K2640, Amberlyst 15) No permanent pore structure Micropores Swelling ! Permanent pore structure Macro- & Micropores 4 – 10 % DVB10 – 20 % DVB PhD symposium, Ghent, 5 th December 2012

Ion exchange resin swells ! 4 25 mL MeOH 10 mL dry K mL wet K mL MeOH 18 % DVB 10 mL dry K1221 > 25 mL wet K mL MeOH 4 % DVB Higher DVB content => less swelling PhD symposium, Ghent, 5 th December 2012

The swelling influences the reaction rate 5 18 % 20 % 4 % total active sites = for all resins % DVB determines the conversion PhD symposium, Ghent, 5 th December 2012 Temperature : 333 K Pressure : 0.1 Mpa MeOH:EtOAc molar ratio: 10:1 Mass of catalyst: 0.5 kg

6 Eley-Rideal reaction mechanism MeOH EtOAc EtOH MeOAc * * ** * * * * * * * * *** * * * ** Reaction Mechanism & kinetic model Total swelling => MeOAc* + MeOH MeOH* + MeOAc Resulting kinetic model PhD symposium, Ghent, 5 th December 2012 MeOH* + EtOAc EtOAc* + MeOH * + MeOH MeOH* MeOH + EtOAc* EtOH + MeOAc* Active (acid) site

Good agreement: model calculations vs. experimental data E A = 49 kJ mol -1 irrespective the catalyst used k SR (gel) = 3 à 4-fold k SR (macroporous) k SR ~ available active sites ~ swelling => affinity of ester is the same for all resin 7 Kinetic modeling results ResinKinetic parameters Ion-exchange equilibrium coefficient Statistical evaluation (10 -6 m 3 kg cat -1 mol -1 s -1 ) (kJ mol -1 ) Total number of experimental data RSSQF K ± ± ± ± K ± ± ± ± K ± ± ± ± Amberlyst ± ± ± ± PhD symposium, Ghent, 5 th December 2012

Thank you for your kind attention 8 PhD symposium, Ghent, 5 th December 2012