title: The transesterification of rapeseed and waste sunflower oils: Mass-transfer and kinetics in a laboratory batch reactor and in an industrial-scale reactor/separator setup.
abstract: We have investigated the transesterification of rapeseed (RO) and waste sunflower (SO) oils with methanol in the presence of potassium hydroxide as a catalyst. The transesterification of tri-acylglycerols was first conducted in a batch reactor. The effect of the temperature on the reaction rates was studied at a constant molar ratio of the alcohol to tri-acylglycerols (6:1) and for a constant concentration of the catalyst (1.0wt%). Size-exclusion chromatography and (1)H NMR spectroscopy were used to quantitatively monitor the transesterification reaction. The mass-transfer coefficients of the tri-acylglycerols during the initial transesterification stage were found to be 0.2-1.2x10(-5)mmin(-1), depending on the type of oil and the temperature. Calculated activation energies implied that at higher temperatures the formation of mono-acylglycerols and glycerole was favored for the SO (93kJ/mol for the forward and 48kJ/mol for the backward reaction) and the RO (47kJ/mol for the forward and 36kJ/mol for the backward reaction), respectively. For the continuous industrial reactor/separator setup, the optimum methanol recycle ratio was established as 0.0550.
authors.affiliation: ZORD Slovenija, 1000 Ljubljana, Slovenia. b.klofutar@zord.org
authors.forename: B
authors.initials: B
authors.lastname: Klofutar
authors.forename: J
authors.initials: J
authors.lastname: Golob
authors.forename: B
authors.initials: B
authors.lastname: Likozar
authors.forename: C
authors.initials: C
authors.lastname: Klofutar
authors.forename: E
authors.initials: E
authors.lastname: Zagar
authors.forename: I
authors.initials: I
authors.lastname: Poljansek
mesh_terms: D002850:Chromatography, Gel; D004951:Esterification; D005229:Fatty Acids, Monounsaturated; D007700:Kinetics; D009682:Magnetic Resonance Spectroscopy; D010938:Plant Oils / Q000737:chemistry*; D000074262:Rapeseed Oil; D000074242:Sunflower Oil
chemical_list: D005229:Fatty Acids, Monounsaturated; D010938:Plant Oils; D000074262:Rapeseed Oil; D000074242:Sunflower Oil