TY - JOUR
T1 - Solvent-free oxidation of 1-phenylethanol catalysed by gold nanoparticles supported on carbon powder materials
AU - Carabineiro, Sónia A.C.
AU - Ribeiro, Ana P.C.
AU - Buijnsters, Josephus G.
AU - Avalos-Borja, Miguel
AU - Pombeiro, Armando J.L.
AU - Figueiredo, José L.
AU - Martins, Luísa M.D.R.S.
PY - 2019
Y1 - 2019
N2 - Gold (1 wt.%) was loaded on several carbon materials, namely, polymer based carbon xerogel, activated carbon, microdiamonds, nanodiamonds, graphite and silicon carbide by double impregnation and sol immobilisation. The obtained catalysts were characterised by N2 adsorption at -196 ºC, high-resolution transmission electron microscopy, high-angle annular dark-field imaging (Z-contrast), temperature programmed desorption, atomic absorption spectroscopy and X-ray photoelectron spectroscopy. The obtained materials were tested on the microwave-assisted solvent-free oxidation of 1-phenylethanol by tert-butyl hydroperoxide (TBHP) to produce acetophenone. The results showed that the catalytic activity was influenced by several factors, namely, the nature of the support, reaction time and temperature, amount of catalyst, presence of additives, among others. The best values for acetophenone yield (99.9%) were obtained with Au deposited on microdiamonds by the colloidal method. Catalyst recyclability was tested up to six consecutive cycles at the optimized conditions for each catalyst, and it was found that Au on microdiamonds, prepared by the colloidal method, also maintained higher activity after several reaction cycles as compared to the other carbon supports.
AB - Gold (1 wt.%) was loaded on several carbon materials, namely, polymer based carbon xerogel, activated carbon, microdiamonds, nanodiamonds, graphite and silicon carbide by double impregnation and sol immobilisation. The obtained catalysts were characterised by N2 adsorption at -196 ºC, high-resolution transmission electron microscopy, high-angle annular dark-field imaging (Z-contrast), temperature programmed desorption, atomic absorption spectroscopy and X-ray photoelectron spectroscopy. The obtained materials were tested on the microwave-assisted solvent-free oxidation of 1-phenylethanol by tert-butyl hydroperoxide (TBHP) to produce acetophenone. The results showed that the catalytic activity was influenced by several factors, namely, the nature of the support, reaction time and temperature, amount of catalyst, presence of additives, among others. The best values for acetophenone yield (99.9%) were obtained with Au deposited on microdiamonds by the colloidal method. Catalyst recyclability was tested up to six consecutive cycles at the optimized conditions for each catalyst, and it was found that Au on microdiamonds, prepared by the colloidal method, also maintained higher activity after several reaction cycles as compared to the other carbon supports.
KW - 1-Phenylethanol
KW - Acetophenone
KW - Carbon supports
KW - Gold nanoparticles
KW - Oxidation
UR - http://www.scopus.com/inward/record.url?scp=85067366415&partnerID=8YFLogxK
U2 - 10.1016/j.cattod.2019.06.041
DO - 10.1016/j.cattod.2019.06.041
M3 - Article
AN - SCOPUS:85067366415
VL - 357 (2020)
SP - 22
EP - 31
JO - Catalysis Today
JF - Catalysis Today
SN - 0920-5861
ER -