Synthesis of trans-pinocarveol from oxidation of β-pinene using multifunctional heterogeneous catalysts

In this contribution, several multifunctional heterogeneous catalysts comprising an acid and a metal function were synthesized by wetness impregnation and tested in the allylic oxidation (with hydrogen peroxide as an oxidizing agent) of β-pinene, a monoterpene which is present in several plants being one of the main constituents of the turpentine oil. Among the tested catalysts, the material containing Pd with a heteropolyacid supported on SBA-15 (Pd/HPA-300/SBA-15) was the best catalyst achieving the most promising results (up to 65% of yield to trans-pinocarveol). Independent on the Pd loading (0.5 wt% or 1.0 wt%) and calcination temperature of the heteropolyacid supported on SBA-15 (200◦C-300◦C), selectivity to trans-pinocarveol remained the same. At the same time the calcination temperature affected conversion, Pd dispersion, acidity, and the surface area. When the support changed to amorphous SiO2 (with a lower surface area < 200 m2 /g) both selectivity and conversion decreased dramatically to values lower than 20%. Weak Brønsted acid sited together with a typical particles shape favors formation and selectivity to the desired product. Laboratory scaling up of β-pinene oxidation was performed (up to 10 mL) achieving the same results in terms of activity and selectivity thereby showing a possibility of a practical implementation of the proposed catalytic system. Kinetic modelling of the reaction was performed to elucidate the determining steps involving in the allylic oxidation of β-pinene. The catalysts showed to be robust since it can be used up to 3 times without apparent changes in both selectivity and conversion but with a slight presence of lixiviation.

• Autores: Villa Holguín, Aída Luz; Sánchez Velandia, Julián Eduardo; Valdivieso Zarate, Laura Milena; Martínez Ortega, Fernando; Mejía, Sol Milena; Wärnå, Johan; Murzin, Dmitry Yu
• Tipo de recurso: Article of investigation
• Fecha de publicación: 2023
• Institución: Universidad de Antioquia
• Repositorio: Repositorio UdeA
• Idioma: eng
• OAI Identifier: oai:bibliotecadigital.udea.edu.co:10495/46670
• Acceso en línea: https://hdl.handle.net/10495/46670
• Palabra clave: Catalizadores; Catalysts; Monoterpenos; Monoterpenes; Biomasa; Biomass; Oxidación alílica; Allylic oxidation; ODS 9: Industria, innovación e infraestructura. Construir infraestructuras resilientes, promover la industrialización inclusiva y sostenible y fomentar la innovación; ODS 12: Producción y consumo responsables. Garantizar modalidades de consumo y producción sostenibles; ODS 13: Acción por el Clima. Adoptar medidas urgentes para combatir el cambio climático y sus efectos
• Rights: openAccess
• License: http://creativecommons.org/licenses/by-nc-nd/4.0/