文摘
Three-dimensional (3D) raspberry-like CuCr2O4 spinel nanoparticles were prepared hydrothermally in the presence of cationic surfactant, cetyltrimethylammonium bromide (CTAB). Detailed characterization of the material was carried out by X-ray diffraction (XRD), inductively coupled plasma鈥揳tomic emission spectroscopy (ICP-AES), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy, and thermogravimetric analysis (TGA). XRD revealed the formation of CuCr2O4 spinel phase, and SEM showed the formation of a 3D raspberry-like structure, composed of 20鈥?0 nm nanoparticles. The raspberry-like particles exhibited excellent catalytic behavior for the hydroxylation of benzene to phenol with H2O2. The influence of reaction parameters were investigated in detail. A benzene conversion of 68.5% with 95% phenol selectivity was achieved at 80 掳C. The catalyst did not show any leaching up to 10 reuses, showing the true heterogeneity of the catalyst. However, significant H2O2 decomposition occurs on the catalyst necessitating its use in 5-fold excess.
Keywords:
CuCr2O4 spinel; 3D raspberry; benzene; selective oxidation; phenol