resumo
Olefin epoxidation is an important transformation for the chemical valorization of olefins, which may derive from renewable sources or domestic/industrial waste. Different post-synthesis strategies were employed to introduce molybdenum species into mesostructured and hierarchical micro-mesoporous catalysts of the type TUD-1 and BEA, respectively, to confer epoxidation activity for the conversion of relatively bulky olefins (e.g., biobased methyl oleate, DL-limonene) to epoxide products, using tert-butyl hydroperoxide as an oxidant. The influences of (i) the type of metal precursor, (ii) type of post-synthesis impregnation method, (iii) type of support and (iv) top-down versus bottom-up synthesis methodologies were studied to achieve superior catalytic performances. Higher epoxidation activity was achieved for a material prepared via (post-synthesis) incipient wetness impregnation of MoO2(acac)(2) (acac = acetylacetonate) on (pre-treated) siliceous TUD-1 and calcination; for example, methyl oleate was converted to the corresponding epoxide with 100% selectivity at 89% conversion (70 degrees C). Catalytic and solid-state characterization studies were conducted to shed light on material stability phenomena.
palavras-chave
TERT-BUTYL HYDROPEROXIDE; MESOPOROUS SILICA; SUPPORTED MOLYBDENA; OLEFIN EPOXIDATION; ZEOLITE; OXIDE; NANOPARTICLES; COMPLEXES; OXIDATION; ALKENES
categoria
Chemistry
autores
Gomes, DM; Neves, P; Antunes, MM; Fernandes, AJS; Pillinger, M; Valente, AA
nossos autores
Anabela Tavares Aguiar Valente
Investigador Principal
Maria Margarida Feitor Pintão Moreno Antunes
Investigador Júnior
Martyn Pillinger
Investigador Principal