Abstract (EN):
The influence of several reactional parameters was investigated on the photocatalytic reduction of benzophenone to the pharmaceutical precursor benzhydrol under UVA-LED radiation. The optical semiconductor titanium dioxide was loaded with 1.0 wt% of noble metals (Pd, Pt and Au) by incipient wetness impregnation method. The TiO2-based materials were characterized by various techniques. Results showed that the benzhydrol selectivity is highly influenced by the nature of the solvent and the presence of KOH (acting as nucleophilic agent). The most efficient system was obtained using 2-propanol, 5.0 mM of KOH and 0.1 g L-1 of catalyst, achieving 100 % selectivity of benzhydrol after 10 mM reaction. Among the TiO2-based materials, the Pd/TiO2 showed high efficiency for benzhydrol formation (in absence KOH) with an enhancing of c.a. 49 % compared with neat TiO2. The decrease of photoluminescence intensity observed for Pd/TiO2 material suggests an effective electron transfer from TiO2 to Pd nanoparticles.
Idioma:
Inglês
Tipo (Avaliação Docente):
Científica
Nº de páginas:
9