During the last decade, niobium-based materials have attracted an increasing attention especially in the field of the catalysis1. Many niobium-based catalysts have been synthesised wih different preparation methods (such as impregnation, sol-gel, chemical vapour deposition) obtaining materials characterized by very different properties, in terms of specific area, nature (Brønsted and Lewis) and strength of the active sites1,2. Therefore, they have been applied in a lot of different processes, in particular involving water in the reaction medium(such as hydrogenation, selective oxidation, condensation and esterification reactions), due to their acidity and high water tolerance3,4.Niobium pentoxide (also known as niobia or niobic acidwhen fully hydrated) represents the most studied niobium oxide; for catalytic purposes, it can also be supported on different materials. Different species (isolated or bulk) may be formed depending on the nature and properties of the support material, niobium precursors, niobium content and synthesis method. For example,acid supports react via hydroxyl groups (Brønsted sites) and basic supports react preferentially on the Lewis sites2,3: in this way, specific catalytic properties are generated. The aim of this work is to comparethe activity between silica and alumina supported niobia catalysts in the epoxidation of methyloleate with hydrogen peroxide.Epoxidized soybean oil and epoxidized methyl esters derived by oils play an important role as building blocks for the preparation of a wide variety of consumer products, such as plasticizers and stabilizers for PVC, and components of lubricants. On the industrial scale, the epoxidation reaction is currently carried out with peroxocarboxylic acids, obtained in situ by using mineral acids as catalysts, according to the Prileshajew method4. The use of hydrogen peroxide as oxidant and heterogeneous catalysts could be an interesting answer to more sustainable and green processes.For this purpose, the main goal of this work is to produce suitable catalysts for the methyloleate epoxidation reaction with hydrogen peroxide.
Epoxidation of Methyloleate by Hydrogen Peroxide catalyzed on supported Niobia / Turco, Rosa; Vitiello, Rosa; Tesser, Riccardo; DI SERIO, Martino. - (2016), pp. 1-2. (Intervento presentato al convegno 3rd International Symposium on Catalysis for Clean Energy and Sustainable Chemistry tenutosi a Madrid nel 7-9 Settembre).
Epoxidation of Methyloleate by Hydrogen Peroxide catalyzed on supported Niobia
TURCO, ROSA;VITIELLO, ROSA;TESSER, RICCARDO;DI SERIO, MARTINO
2016
Abstract
During the last decade, niobium-based materials have attracted an increasing attention especially in the field of the catalysis1. Many niobium-based catalysts have been synthesised wih different preparation methods (such as impregnation, sol-gel, chemical vapour deposition) obtaining materials characterized by very different properties, in terms of specific area, nature (Brønsted and Lewis) and strength of the active sites1,2. Therefore, they have been applied in a lot of different processes, in particular involving water in the reaction medium(such as hydrogenation, selective oxidation, condensation and esterification reactions), due to their acidity and high water tolerance3,4.Niobium pentoxide (also known as niobia or niobic acidwhen fully hydrated) represents the most studied niobium oxide; for catalytic purposes, it can also be supported on different materials. Different species (isolated or bulk) may be formed depending on the nature and properties of the support material, niobium precursors, niobium content and synthesis method. For example,acid supports react via hydroxyl groups (Brønsted sites) and basic supports react preferentially on the Lewis sites2,3: in this way, specific catalytic properties are generated. The aim of this work is to comparethe activity between silica and alumina supported niobia catalysts in the epoxidation of methyloleate with hydrogen peroxide.Epoxidized soybean oil and epoxidized methyl esters derived by oils play an important role as building blocks for the preparation of a wide variety of consumer products, such as plasticizers and stabilizers for PVC, and components of lubricants. On the industrial scale, the epoxidation reaction is currently carried out with peroxocarboxylic acids, obtained in situ by using mineral acids as catalysts, according to the Prileshajew method4. The use of hydrogen peroxide as oxidant and heterogeneous catalysts could be an interesting answer to more sustainable and green processes.For this purpose, the main goal of this work is to produce suitable catalysts for the methyloleate epoxidation reaction with hydrogen peroxide.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
