Environmentally friendly synthesis of CeO2 nanoparticles for the catalytic oxidation of benzyl alcohol to benzaldehyde and selective detection of nitrite.

Cerium oxide nanoparticles (CeO2 NPs) are favorable in nanotechnology based on some remarkable properties. In this study, the crystalline CeO2 NPs are successfully prepared by an efficient microwave combustion (MCM) and conventional route sol-gel (CRSGM) methods. The structural morphology of the as-prepared CeO2 NPs was investigated by various spectroscopic and analytical techniques. Moreover, the XRD pattern confirmed the formation of CeO2 NPs as a face centered cubic structure. The magnetometer studies indicated the low saturation magnetization (23.96 emu/g) of CeO2 NPs for weak paramagnetic and high saturation magnetization (32.13 emu/g) of CeO2 NPs for super paramagnetic. After that, the oxidation effect of benzyl alcohol was investigated which reveals good conversion and selectivity. Besides, the CeO2 NPs modified glassy carbon electrode (GCE) used for the detection of nitrite with linear concentration range (0.02-1200 µM), low limit of detection (0.21 µM) and higher sensitivity (1.7238 µAµM-1 cm-2). However, the CeO2 NPs modified electrode has the fast response, high sensitivity and good selectivity. In addition, the fabricated electrode is applied for the determination of nitrite in various water samples. Eventually, the CeO2 NPs can be regarded as an effective way to enhance the catalytic activity towards the benzyl alcohol and nitrite.

Hydroprocessing of sunflower oil-gas oil blends over sulfided Ni-Mo-Al-zeolite beta composites.

Mixtures of sunflower oil and a straight run gas oil in the diesel fuel range were hydroprocessed over sulfided NiO(3%)-MoO3(12%)-γ-Al2O3 incorporating 0, 15 or 30 wt.% zeolite beta (BEA). The studies were carried out at 320-350 °C; 30-60 bars, and weight hourly space velocities (WHSV), 1-4 h(-1). Catalyst containing 30% BEA achieved nearly 100 % conversion of the vegetable oil into hydrocarbons at 330 °C, 60 bars and a WHSV of 2 h(-1) compared to 95.5% by the Ni-Mo-γ-alumina catalyst without BEA. Hydroprocessing with blends containing oleic acid revealed that the catalysts were able to transform the acid into hydrocarbons. An analysis of the ratios of the n-C18 and n-C17 paraffins formed from the vegetable oil at different process conditions revealed that the catalyst containing 15% BEA was most active for hydrodeoxygenation. The gas oil-hydrodesulfurization activity of the Ni-Mo-Al2O3 was enhanced by the addition of BEA by more than 10%.