Cu-Catalyzed Hydrodehalogenation of Brominated Aromatic Pollutants in Aqueous Solution

The catalytic effect of copper in Devarda’s Al-Cu-Zn alloy (Dev. alloy) and sole metallic copper, copper salts and copper oxides in the coaction of NaBH4 within the hydrodehalogenation (HDH) of polybrominated phenols, such as the herbicide Bromoxynil in alkaline aqueous solution has been investigated. Namely, the hydrodebromination (HDB) activity of Dev. alloy/NaOH system has been compared to heterogeneous Cu-based catalysts using NaBH4 as a reductant. Differences in the solid-state structures of used Cu-based heterogeneous catalysts after the mentioned HDB process have been studied using the powder XRD and SEM techniques. It was found that some of the used copper-based catalysts are reusable and reasonably effective even at room temperature. Efficiency of the most promising copper-based reduction systems (Dev. alloy/NaOH and Cu-based catalysts/NaBH4) have been successfully tested within the HDB of industrially important brominated flame retardant tetrabromobisphenol A (TBBPA). Dev. alloy/NaOH and Cu-based catalyst generated in-situ within the CuSO4/NaBH4 produced were recognized as the most active HDB agents for complete debromination of both BRX and TBBPA.

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Catalytic Effect of Copper on Ozonation in Aqueous Solution

Ozone Science and Engineering ◽

10.1080/01919512.2021.1889329 ◽

2021 ◽

pp. 1-8

Author(s):

Naoyuki Kishimoto ◽

Haruki Arai

Keyword(s):

Aqueous Solution ◽

Catalytic Effect ◽

Effect Of Copper

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Catalytic Effect of Copper on Ozonation in Aqueous Solution

Ozone Science and Engineering ◽

10.1080/01919512.2021.1927593 ◽

2021 ◽

pp. 1-7

Author(s):

Naoyuki Kishimoto ◽

Haruki Arai

Keyword(s):

Aqueous Solution ◽

Catalytic Effect ◽

Effect Of Copper

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In-situ/operando techniques to identify active sites for thermochemical conversion of CO2 over heterogeneous catalysts

Journal of Energy Chemistry ◽

10.1016/j.jechem.2021.03.054 ◽

2021 ◽

Author(s):

Kai Feng ◽

Yaning Wang ◽

Man Guo ◽

Jingpeng Zhang ◽

Zhengwen Li ◽

...

Keyword(s):

Active Sites ◽

Heterogeneous Catalysts ◽

Thermochemical Conversion

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Morphology Controlled Synthesis of γ-Al2O3 Nano-Crystallites in Al@Al2O3 Core–Shell Micro-Architectures by Interfacial Hydrothermal Reactions of Al Metal Substrates

Nanomaterials ◽

10.3390/nano11020310 ◽

2021 ◽

Vol 11 (2) ◽

pp. 310

Author(s):

Dohyeon Han ◽

Doohwan Lee

Keyword(s):

Electrostatic Interactions ◽

Heterogeneous Catalysts ◽

Metal Substrate ◽

Inorganic Anions ◽

Core Shell ◽

Hydroxyl Groups ◽

Hydrothermal Reactions ◽

Fine Control ◽

Reaction Processes

Fine control of morphology and exposed crystal facets of porous γ-Al2O3 is of significant importance in many application areas such as functional nanomaterials and heterogeneous catalysts. Herein, a morphology controlled in situ synthesis of Al@Al2O3 core–shell architecture consisting of an Al metal core and a porous γ-Al2O3 shell is explored based on interfacial hydrothermal reactions of an Al metal substrate in aqueous solutions of inorganic anions. It was found that the morphology and structure of boehmite (γ-AlOOH) nano-crystallites grown at the Al-metal/solution interface exhibit significant dependence on temperature, type of inorganic anions (Cl−, NO3−, and SO42−), and acid–base environment of the synthesis solution. Different extents of the electrostatic interactions between the protonated hydroxyl groups on (010) and (001) facets of γ-AlOOH and the inorganic anions (Cl−, NO3−, SO42−) appear to result in the preferential growth of γ-AlOOH toward specific crystallographic directions due to the selective capping of the facets by adsorption of the anions. It is hypothesized that the unique Al@Al2O3 core–shell architecture with controlled morphology and exposed crystal-facets of the γ-Al2O3 shell can provide significant intrinsic catalytic properties with enhanced heat and mass transport to heterogeneous catalysts for applications in many thermochemical reaction processes. The direct fabrication of γ-Al2O3 nano-crystallites from Al metal substrate with in-situ modulation of their morphologies and structures into 1D, 2D, and 3D nano-architectures explored in this work is unique and can offer significant opportunities over the conventional methods.

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In situ construction of phenanthroline-based cationic radical porous hybrid polymers for metal-free heterogeneous catalysis

Journal of Materials Chemistry A ◽

10.1039/d0ta12018a ◽

2021 ◽

Vol 9 (12) ◽

pp. 7556-7565

Author(s):

Guojian Chen ◽

Yadong Zhang ◽

Ke Liu ◽

Xiaoqing Liu ◽

Lei Wu ◽

...

Keyword(s):

Heterogeneous Catalysis ◽

Heterogeneous Catalysts ◽

Hybrid Polymers ◽

Metal Free ◽

Oxidation Of Sulfides

Constructing phenanthroline-based cationic radical porous hybrid polymers as versatile metal-free heterogeneous catalysts for both oxidation of sulfides and CO2 conversion.

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Comment on ‘‘In situ photoluminescence spectral study of porous Si in HF aqueous solution’’ [Appl. Phys. Lett. 65, 1653 (1994)]

Applied Physics Letters ◽

10.1063/1.113701 ◽

1995 ◽

Vol 66 (21) ◽

pp. 2912-2913 ◽

Cited By ~ 4

Author(s):

M. Davison ◽

K. P. O’Donnell ◽

U. M. Noor ◽

D. Uttamchandani ◽

L. E. A. Berlouis

Keyword(s):

Aqueous Solution ◽

Spectral Study ◽

Porous Si

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Radiation-initiated high strength chitosan/lithium sulfonate double network hydrogel/aerogel with porosity and stability for efficient CO2 capture

RSC Advances ◽

10.1039/d1ra03041h ◽

2021 ◽

Vol 11 (33) ◽

pp. 20486-20497

Author(s):

Zhiyan Liu ◽

Rui Ma ◽

Wenjie Du ◽

Gang Yang ◽

Tao Chen

Keyword(s):

Aqueous Solution ◽

High Strength ◽

Beam Radiation ◽

Chitosan Hydrogel ◽

Double Network ◽

Electron Beam Radiation ◽

Freeze Dried ◽

Urea Aqueous Solution ◽

Capture Capacity

Chitosan hydrogel is regenerated from alkali/urea aqueous solution and the lithium sulfonate second network is introduced by electron beam radiation-initiated in situ free radical polymerization. The freeze-dried aerogel has CO2 capture capacity.

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Ambient base-free glycerol oxidation over bimetallic PdFe/SiO2 by in situ generated active oxygen species

Research on Chemical Intermediates ◽

10.1007/s11164-020-04333-2 ◽

2021 ◽

Author(s):

Ricci Underhill ◽

Mark Douthwaite ◽

Richard J. Lewis ◽

Peter J. Miedziak ◽

Robert D. Armstrong ◽

...

Keyword(s):

Heterogeneous Catalysts ◽

Bimetallic Catalyst ◽

Electron Paramagnetic Resonance Spectroscopy ◽

Active Oxygen Species ◽

Catalytic Performance ◽

Resonance Spectroscopy ◽

Oxygen Species ◽

Paramagnetic Resonance ◽

Temperature Oxidation

AbstractLow temperature oxidation of alcohols over heterogeneous catalysts is exceptionally challenging, particularly under neutral conditions. Herein, we report on an efficient, base-free method to oxidise glycerol over a 0.5%Pd-0.5%Fe/SiO2 catalyst at ambient temperature in the presence of gaseous H2 and O2. The exceptional catalytic performance was attributed to the in situ formation of highly reactive surface-bound oxygenated species, which promote the dehydrogenation on the alcohol. The PdFe bimetallic catalyst was determined to be significantly more active than corresponding monometallic analogues, highlighting the important role both metals have in this oxidative transformation. Fe leaching was confirmed to occur over the course of the reaction but sequestering experiments, involving the addition of bare carbon to the reactions, confirmed that the reaction was predominantly heterogeneous in nature. Investigations with electron paramagnetic resonance spectroscopy suggested that the reactivity in the early stages was mediated by surface-bound reactive oxygen species; no homogeneous radical species were observed in solution. This theory was further evidenced by a direct H2O2 synthesis study, which confirmed that the presence of Fe in the bimetallic catalyst neither improved the synthesis of H2O2 nor promoted its decomposition over the PdFe/SiO2 catalyst.

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Fabrication of monodisperse polypyrrole/SBA-15 composite for the selective removal of Cr(Ⅵ) from aqueous solutions

New Journal of Chemistry ◽

10.1039/d1nj00717c ◽

2021 ◽

Author(s):

Liang Wang ◽

Peng Gao ◽

Mengxin Liu ◽

Ziqing Huang ◽

Shixia Lan ◽

...

Keyword(s):

Aqueous Solution ◽

Aqueous Solutions ◽

Adsorption Process ◽

In Situ Polymerization ◽

Selective Removal ◽

Factors Affecting

Monodisperse polypyrrole/SBA-15 composite (PPy/SBA-15) was fabricated by in-situ polymerization and used for Cr(Ⅵ) adsorption from aqueous solution. PPy/SBA-15 was characterized by numerous approaches. Factors affecting the Cr(Ⅵ) adsorption process included...

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