scholarly journals Near-IR squaraine dye–loaded gated periodic mesoporous organosilica for photo-oxidation of phenol in a continuous-flow device

2015 ◽  
Vol 1 (8) ◽  
pp. e1500390 ◽  
Author(s):  
Parijat Borah ◽  
Sivaramapanicker Sreejith ◽  
Palapuravan Anees ◽  
Nishanth Venugopal Menon ◽  
Yuejun Kang ◽  
...  
Keyword(s):  
Continuous Flow ◽  
Heterogeneous Catalysts ◽  
Near Infrared ◽  
Periodic Mesoporous Organosilica ◽  
Photo Oxidation ◽  
Mesoporous Organosilica ◽  
Squaraine Dye ◽  
Flow Device ◽  
Catalytically Active ◽  
Oxidation Of Phenol

Periodic mesoporous organosilica (PMO) has been widely used for the fabrication of a variety of catalytically active materials. We report the preparation of novel photo-responsive PMO with azobenzene-gated pores. Upon activation, the azobenzene gate undergoes trans-cis isomerization, which allows an unsymmetrical near-infrared squaraine dye (Sq) to enter into the pores. The gate closure by cis-trans isomerization of the azobenzene unit leads to the safe loading of the monomeric dye inside the pores. The dye-loaded and azobenzene-gated PMO (Sq-azo@PMO) exhibits excellent generation of reactive oxygen species upon excitation at 664 nm, which can be effectively used for the oxidation of phenol into benzoquinone in aqueous solution. Furthermore, Sq-azo@PMO as the catalyst was placed inside a custom-built, continuous-flow device to carry out the photo-oxidation of phenol to benzoquinone in the presence of 664-nm light. By using the device, about 23% production of benzoquinone with 100% selectivity was achieved. The current research presents a prototype of transforming heterogeneous catalysts toward practical use.

Periodic mesoporous organosilicas functionalized with iron(iii) complexes: preparation, characterization and catalysis on direct hydroxylation of benzene to phenol

RSC Advances ◽  
2016 ◽  
Vol 6 (100) ◽  
pp. 98406-98412 ◽  
Author(s):  
Erxing Gu ◽  
Wei Zhong ◽  
Xiaoming Liu
Keyword(s):  
Periodic Mesoporous Organosilica ◽  
Periodic Mesoporous Organosilicas ◽  
Hydroxylation Of Benzene ◽  
Mesoporous Organosilica ◽  
Oxidation Of Phenol ◽  
Mesoporous Organosilicas ◽  
Direct Hydroxylation

Incorporation of iron(iii) complexes into hydrophobic periodic mesoporous organosilica prevents over-oxidation of phenol and hence significantly improves both the selectivity and yield of phenol compared with their corresponding homogeneous iron precursors.

scholarly journals Phthalocyanine–Virus Nanofibers as Heterogeneous Catalysts for Continuous‐Flow Photo‐Oxidation Processes

2019 ◽  
Vol 31 (39) ◽  
pp. 1902582 ◽  
Author(s):  
Eduardo Anaya‐Plaza ◽  
Ana Aljarilla ◽  
Grégory Beaune ◽  
Nonappa ◽  
Jaakko V. I. Timonen ◽  
...  
Keyword(s):  
Continuous Flow ◽  
Heterogeneous Catalysts ◽  
Photo Oxidation ◽  
Oxidation Processes

Evaluation of the disinfection potential of low chlorine concentrations in tap water using immobilised enterococcus faecium in a continuous flow device

1997 ◽  
Vol 35 (11-12) ◽  
pp. 77-80 ◽  
Author(s):  
A. Wiedenmann ◽  
M. Braun ◽  
K. Botzenhart
Keyword(s):  
Distribution System ◽  
Enterococcus Faecium ◽  
Continuous Flow ◽  
Tap Water ◽  
Test System ◽  
Batch Experiments ◽  
Membrane Filters ◽  
Upper Limit ◽  
Flow Device ◽  
Faecal Streptococci

A simple continuous flow device in which bacteria were immobilised on membrane filters and flushed with tap water with free chlorine residuals of 0.05, 0.1, 0.2 and 0.4mg/L at pH 7.7 and 10°C, has been used for disinfection experiments with faecal streptococci. A 99.99% reduction of Enterococcus faecium was observed between 3.4–5.2min (0.05mg/L), between 2.8–4.1min (0.1mg/L), between 1.7–3.1min (0.2mg/L) and between 0.8–2.1min (0.4mg/L). CT-products covered a range of 0.17 (0.05mg/L, lower limit) up to 0.85mg/L/min (0.4mg/L, upper limit). The test system is suggested as a more reliable alternative to batch experiments when the disinfection potential of low chlorine concentrations acting for several minutes has to be evaluated. The system cannot be used to demonstrate exact reduction kinetics but it allows the calculation of CT values and the evaluation of the disinfection potential of chlorinated water at any point of a distribution system where initial chlorine concentrations may have already remarkably declined.

Light-harvesting photocatalysis for H2 evolution by methylacridone-bridged periodic mesoporous organosilica

2021 ◽  
Vol 287 ◽  
pp. 119965
Author(s):  
Yasutomo Goto ◽  
Ken-ichi Yamanaka ◽  
Masataka Ohashi ◽  
Yoshifumi Maegawa ◽  
Shinji Inagaki
Keyword(s):  
Light Harvesting ◽  
H2 Evolution ◽  
Periodic Mesoporous Organosilica ◽  
Mesoporous Organosilica
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