Phenyl modification of Mn‐containing mesoporous silica and catalytic oxidation of toluene

Abstract

BACKGROUND: Catalytic oxidation of toluene with dioxygen is a fundamental industrial technology because the oxidized products are important intermediates for many fine chemicals. In this study, phenyl modification was utilized to alter catalyst surface characteristics in order to enhance activity.

Aliphatic amines modified CoO nanoparticles for catalytic oxidation of aromatic hydrocarbon with molecular oxygen

“…Many other factors that could enhance the reaction rate of a heterogeneous catalysis reaction exist, such as the electronic state [13] and the microenvironment [14]. The surface hydrophobicity of the catalyst was advantageous to the hydrocarbon oxidation owing to the nature of the process [15][16][17][18][19]. The CoOx nanoparticles exhibited hydrophilic properties toward the polar hydroxyl groups on the surface.…”

Preparation of superhydrophobic cauliflower-like silica nanospheres with tunable water adhesion

“…Typical bands associated with formation of a condensed siloxane network were present in all materials (Si-O-Si bands around 1096, 798, and 465 cm À1 ). 41,46 Typical bands associated with phenyl groups appear in the spectra of the phenyl groups-containing silica nanospheres. The aromatic C]C ring stretching (weak peaks around 1432 cm À1 ) and mono-substituted benzene out-of-plane bending vibration (around 739 and 698 cm À1 ) are detected, which confirm the presence of phenyl groups in the materials.…”

“…The aromatic C]C ring stretching (weak peaks around 1432 cm À1 ) and mono-substituted benzene out-of-plane bending vibration (around 739 and 698 cm À1 ) are detected, which confirm the presence of phenyl groups in the materials. 41,46 With the increase of initial amount of PTES the intensity of the typical bands associated with phenyl groups increase while the intensity of the hydroxyl band (1637 cm À1 ) decreases. These results manifest that the amount of hydroxyl groups decreased with their substitution by phenyl groups on the surface.…”

Efficient catalytic oxidation of methyl aromatic hydrocarbon with N-alkyl pyridinium salts

“…The surface organic modication strategy was illustrated for inorganic heterogeneous catalysts in our previous work to modulate the surface hydrophilicity/ hydrophobicity; the hydrophobic or superhydrophobic catalyst showed better lipophilicity and good catalytic activity was obtained at lower temperatures. [18][19][20][21] Compared with those heterogeneous catalysts, homogeneous organic catalysts own better solubility and could be used under mild conditions. For example, metal-complex or the metal-complexation promoted organic N-hydroxyl catalytic systems were reported for the conversion of hydrocarbon.…”