title: Disproportionation of rosin on an industrial Pd/C catalyst: reaction pathway and kinetic model discrimination.
abstract: In this work, a phenomenological study of the isomerisation and disproportionation of rosin acids using an industrial 5% Pd on charcoal catalyst from 200 to 240°C is carried out. Medium composition is determined by elemental microanalysis, GC-MS and GC-FID. Dehydrogenated and hydrogenated acid species molar amounts in the final product show that dehydrogenation is the main reaction. Moreover, both hydrogen and non-hydrogen concentration considering kinetic models are fitted to experimental data using a multivariable non-linear technique. Statistical discrimination among the proposed kinetic models lead to the conclusion hydrogen considering models fit much better to experimental results. The final kinetic model involves first-order isomerisation reactions of neoabietic and palustric acids to abietic acid, first-order dehydrogenation and hydrogenation of this latter acid, and hydrogenation of pimaric acids. Hydrogenation reactions are partial first-order regarding the acid and hydrogen.
authors.affiliation: Departamento Ingeniería Química, Facultad CC Químicas, Universidad Complutense, Madrid, Spain.
authors.forename: Juan Carlos
authors.initials: JC
authors.lastname: Souto
authors.forename: Pedro
authors.initials: P
authors.lastname: Yustos
authors.forename: Miguel
authors.initials: M
authors.lastname: Ladero
authors.forename: Felix
authors.initials: F
authors.lastname: Garcia-Ochoa
mesh_terms: D000383:Agriculture / Q000379:methods; D002244:Carbon / Q000737:chemistry*; D002384:Catalysis; D003198:Computer Simulation; D007700:Kinetics; D008956:Models, Chemical; D010165:Palladium / Q000737:chemistry*; D012116:Resins, Plant / Q000737:chemistry*; D014197:Trees / Q000737:chemistry*; D014934:Wood / Q000737:chemistry*
chemical_list: D012116:Resins, Plant; D010165:Palladium; D002244:Carbon; C013893:rosin