Pd/MgO catalysts for aerobic oxidation of aromatic alcohols.

• Main Author: Lim, Ban Pei.
• Other Authors: Yang Yanhui
• Format: Final Year Project
• Language: English
• Published: 2010
• Subjects: DRNTU::Engineering::Chemical engineering::Chemical processes
• Online Access: http://hdl.handle.net/10356/39445
• Institution: Nanyang Technological University

The solvent-free selective oxidation of benzyl alcohol to benzaldehyde on Pd/MgO catalyst has been investigated. Pd/MgO catalysts have been prepared using three different types of methods, namely Impregnation (IMP), Homogeneous Deposition Precipitation (HDP) and Microwave (MW). The prepared catalysts were tested and microwave-prepared catalyst was found to show the greatest catalytic performance. Also, Pd/MgO catalysts with different weight percentages of metal loading were prepared and tested in the benzyl alcohol oxidation. It was shown that 1 wt% Pd/MgO showed the greatest result in term of conversion and TOF. Besides, benzyl alcohol oxidation reaction was run for 12 hours and the sample of products were taken and studied carefully at certain set period of time. The conversion, selectivity and TOF of reaction were observed to be varied throughout the 12-hour period. In addition to benzyl alcohol, other aromatic alcohols such as α-methyl benzyl alcohol and 4-nitro benzyl alcohol were oxidized using Pd/MgO catalysts and the oxidation results were found to be significantly different. The differences were attributed to the nature of the susbstituent groups, which were electron donating or electron withdrawing. Lastly, Pd/MgO catalyst was recycled for four cycles and its performance was studied in every cycle of reaction. It was observed that the catalytic performance of recycled Pd/MgO was consistent throughout the four cycles of reaction. The consistency of Pd/MgO catalyst could be attributed to the recyclable property of the catalyst as well as no leaching of Pd metal during the filtration process.