Palladium‐Supported Nanoceria: A Highly Efficient Catalyst for Solvent‐Free Selective Oxidation of Ethylbenzene to Acetophenone

Abstract

The benzylic C−H oxidation of ethylbenzene, a toxic petroleum waste, to high value‐added acetophenone is a fundamental yet important chemical transformation. Herein, palladium nanoparticles were immobilized on a highly mesoporous CeO2 surface for enhancing the catalytic activity. The Pd/CeO2nanocomposite was employed in the benzylic C−H oxidation of ethylbenzene under solvent‐free conditions and using tert‐butyl hydroperoxide as oxidant which displayed high conversion of 99.8% and a selectivity of 79% towards acetophenone. Moreover, the Pd/CeO2 catalysts were highly stable and could be recycled up to the fifth catalytic cycle without remarkable loss in its catalytic activity.

Solvent‐free selective oxidation of ethylbenzene with molecular oxygen catalyzed by cobalt catalysts supported on exfoliated carbon nitride

“…Wherein, the oxidants generally include molecular oxygen, [9] hydrogen peroxide, [10–11] and tert ‐butyl hydrogen peroxide [12] . Although the latter two oxidants can allow the oxidation of EB to process in much milder reaction conditions, the high cost of using such oxidants undoubtedly restricts further industrial implementation [8] . On the other hand, molecular oxygen is widely available and very inexpensive but demands high operating temperature and pressure [13] .…”

A Keggin-type polyoxometalate-based metal–organic complex as a highly efficient heterogeneous catalyst for the selective oxidation of alkylbenzenes

“…and low-cost drugs. [1][2][3] In general, C-H bonds are very strong and relatively unreactive, and widely exist in organic materials, natural hydrocarbons, and petroleum contaminants. 4,5 Hence, activating C-H bonds in materials and converting these useless materials into valuable compounds is an important, economic and green step in synthetic chemistry.…”

“…4,5 Hence, activating C-H bonds in materials and converting these useless materials into valuable compounds is an important, economic and green step in synthetic chemistry. 6,7 Up to now, a few catalysts such as noble metals (Pd, Ru), 1,8 non-noble metal catalysts, 9,10 earth abundant metal catalysts, 11,12 and organic molecules 13,14 have been selected for the conversion of alkylbenzenes; however, some of these are neither recyclable nor inexpensive. Therefore, an economical and efficient heterogeneous catalyst without any additives is more desirable.…”

Morphology Modulated Photocatalytic Activity of CeO2 Nanostructures for Selective Oxidation of Biobased Alpha‐Pinene to Oxygenates

“…[4] Moreover, CeO 2 has been used extensively as a promoter in CO oxidation, [5] and other numerous selective liquid-phase oxidation reactions for the synthesis of organic chemicals. [6][7][8] The significant interest in CeO 2 based nanomaterials stems from the excellent chemical and physical properties, such as their superior chemical stability and good oxygen storage or release capacity. [9,10] Furthermore, CeO 2 nanostructures possesses structural defects properties that are attributed to the tunable coexistence of Ce 3 + and Ce 4 + ions in the CeO 2 crystal, which enhances the redox reactivity, oxygen mobility and surface to volume ratio with respect to the bulk CeO 2 .…”

“…Cerium dioxide (CeO 2 ) is an abundant rare earth oxide that has high technological importance in various catalytic processes, including three‐way catalysis, [1] low temperature water gas shift (WGS) reactions, [2] oxygen sensors, [3] and fuel cells [4] . Moreover, CeO 2 has been used extensively as a promoter in CO oxidation, [5] and other numerous selective liquid‐phase oxidation reactions for the synthesis of organic chemicals [6–8] . The significant interest in CeO 2 based nanomaterials stems from the excellent chemical and physical properties, such as their superior chemical stability and good oxygen storage or release capacity [9,10] .…”