scholarly journals Low temperature oxidation of o-xylene with hydrogen peroxide in the presence of vanadium xerogels

2017 ◽  
pp. 26-31
Author(s):  
Nurlykyz Yesmurzaeva ◽  
Roza Tursunova ◽  
Bagadat Selenova ◽  
Daulet Kaldybekov ◽  
Sarkyt Kudaibergenov
Keyword(s):  
Hydrogen Peroxide ◽  
Catalytic Activity ◽  
Titanium Oxide ◽  
Oxidation Process ◽  
High Catalytic Activity ◽  
Vanadium Catalyst ◽  
Low Temperature Oxidation ◽  
Temperature Oxidation ◽  
Mild Conditions ◽  
Physicochemical Methods

The present work is dedicated to investigation of vanadium xerogels deposited on titanium oxide for the oxidation process of o-xylene by hydrogen peroxide under the mild conditions. The structure of deposited vanadium catalyst and sizes of vanadium xerogels nanoparticles were investigated by physicochemical methods. The nano-sized particles (5-8 nm) of xerogel vanadium deposited on titanium oxide exhibit high catalytic activity in the decomposition of hydrogen peroxide and in the oxidation of o-xylene by hydrogen peroxide under mild conditions.

scholarly journals Influence of Co-Precipitation Agent on the Structure, Texture and Catalytic Activity of Au-CeO2 Catalysts in Low-Temperature Oxidation of Benzyl Alcohol

Catalysts ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 641
Author(s):  
Lukasz Wolski ◽  
Grzegorz Nowaczyk ◽  
Stefan Jurga ◽  
Maria Ziolek
Keyword(s):  
Gold Nanoparticles ◽  
Catalytic Activity ◽  
Low Temperature ◽  
Benzyl Alcohol ◽  
Low Temperature Oxidation ◽  
Temperature Oxidation ◽  
Oxidation Of Benzyl Alcohol ◽  
Key Factor ◽  
Au Particle Size ◽  
Co Precipitation

The aim of the study was to establish the influence of a co-precipitation agent (i.e., NaOH–immediate precipitation; hexamethylenetetramine/urea–gradual precipitation and growth of nanostructures) on the properties and catalytic activity of as-synthesized Au-CeO2 nanocomposites. All catalysts were fully characterized with the use of XRD, nitrogen physisorption, ICP-OES, SEM, HR-TEM, UV-vis, XPS, and tested in low-temperature oxidation of benzyl alcohol as a model oxidation reaction. The results obtained in this study indicated that the type of co-precipitation agent has a significant impact on the growth of gold species. Immediate co-precipitation of Au-CeO2 nanostructures with the use of NaOH allowed obtainment of considerably smaller and more homogeneous in size gold nanoparticles than those formed by gradual co-precipitation and growth of Au-CeO2 nanostructures in the presence of hexamethylenetetramine or urea. In the catalytic tests, it was established that the key factor promoting high activity in low-temperature oxidation of benzyl alcohol was size of gold nanoparticles. The highest conversion of the alcohol was observed for the catalyst containing the smallest Au particle size (i.e., Au-CeO2 nanocomposite prepared with the use of NaOH as a co-precipitation agent).

Titanium Dioxide-Supported Sulfonated Low Rank Coal as Catalysts in the Oxidation of Styrene with Aqueous Hydrogen Peroxide

2014 ◽  
Vol 69 (5) ◽  
Author(s):  
Mukhamad Nurhadi ◽  
Jon Efendi ◽  
Lee Siew Ling ◽  
Teuku Meurah Indra Mahlia ◽  
Ho Chin Siong ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Titanium Dioxide ◽  
Catalytic Activity ◽  
Diffuse Reflectance Spectroscopy ◽  
Low Rank ◽  
Bet Surface Area ◽  
High Catalytic Activity ◽  
Low Rank Coal ◽  
X Ray Diffraction ◽  
Aqueous Hydrogen Peroxide

Titanium dioxide supported sulfonated low rank coal catalyst possesses high catalytic activity in liquid phase oxidation of styrene with aqueous hydrogen peroxide at room temperature. The catalysts were prepared by sulfonation with concentrated sulfuric acid and impregnation of titanium dioxide (500-2500 µmol). The effect of titanium dioxide impregnation and calcinations on the catalysts were studied by X-ray diffraction, UV-vis diffuse reflectance spectroscopy, Fourier transform infrared spectroscopy, BET surface area, field emission scanning electron microscopy and hydrophobicity measurement. The catalytic activity of the catalysts in the oxidation of styrene by aqueous H2O2 without calcination increased when the amount of titanium dioxide increased. Meanwhile, the catalytic activity of the catalyst calcined at 500oC for 2 h was lower than before calcination. It is suggested that the agglomeration of titanium dioxide and hydrophobicity play important role in the catalytic activity of titanium dioxide-supported sulfonated low rank coal in the oxidation of styrene with aqueous H2O2. 

Hollow structured CoSn(OH)6-supported Pt for effective room-temperature oxidation of gaseous formaldehyde

2016 ◽  
Vol 09 (06) ◽  
pp. 1642009 ◽  
Author(s):  
Jing Zhou ◽  
Yong Zhao ◽  
Lifan Qin ◽  
Chen Zeng ◽  
Wei Xiao
Keyword(s):  
Electron Microscopy ◽  
Catalytic Activity ◽  
Room Temperature ◽  
Synergetic Effect ◽  
Hollow Structure ◽  
Pt Nanoparticles ◽  
Hydroxyl Groups ◽  
High Catalytic Activity ◽  
Temperature Oxidation ◽  
X Ray

Uniform CoSn(OH)6 hollow nanoboxes and the derivative with Pt loading (Pt/CoSn(OH)6) were herein synthesized and characterized by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). SEM and TEM analyses showed that CoSn(OH)6 possessed mesoporous hollow structure and Pt nanoparticles with size of 2–8[Formula: see text]nm were uniformly dispersed on the surface of CoSn(OH)6 nanoboxes. The performances of the catalysts for the formaldehyde (HCHO) removal at room temperature were evaluated. These Pt/CoSn(OH)6 catalysts exhibited a remarkable catalytic activity as well as stability for room-temperature oxidative decomposition of gaseous HCHO, while the corresponding CoSn(OH)6 only showed adsorption. The synergetic effect between the highly dispersed Pt nanoparticles and the CoSn(OH)6 nanoboxes with mesoporous hollow structure, a large surface area and abundant surface hydroxyl groups is considered to be the main reason for the observed high catalytic activity of Pt/CoSn(OH)6.

scholarly journals Catalytic Degradation of Chitosan by Supported Heteropoly Acids in Heterogeneous Systems

Catalysts ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 1078
Author(s):  
Hang Zhang ◽  
Zhipeng Ma ◽  
Yunpeng Min ◽  
Huiru Wang ◽  
Ru Zhang ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Molecular Weight ◽  
Catalytic Activity ◽  
Activated Carbon ◽  
Reaction Time ◽  
High Molecular Weight ◽  
Reaction Temperature ◽  
Water Soluble ◽  
High Catalytic Activity ◽  
High Molecular Weight Chitosan

Several kinds of composite materials with phosphotungstic acid (PTA) as the catalyst were prepared with activated carbon as support, and their structures were characterized. According to the Box–Behnken central combination principle, the mathematical model of the heterogeneous system is established. Based on the single-factor experiments, the reaction temperature, the reaction time, the amount of hydrogen peroxide and the loading capacity of PTA were selected as the influencing factors to study the catalyzed oxidation of hydrogen peroxide and degradation of high molecular weight chitosan. The results of IR showed that the catalyst had a Keggin structure. The results of the mercury intrusion test showed that the pore structure of the supported PTA catalyst did not change significantly, and with the increase of PTA loading, the porosity and pore volume decreased regularly, which indicated that PTA molecules had been absorbed and filled into the pore of activated carbon. The results of Response Surface Design (RSD) showed that the optimum reaction conditions of supported PTA catalysts for oxidative degradation of high molecular weight chitosan by hydrogen peroxide were as follows: reaction temperature was 70 ℃, reaction time was 3.0 h, the ratio of hydrogen peroxide to chitosan was 2.4 and the catalyst loading was 30%. Under these conditions, the yield and molecular weight of water-soluble chitosan were 62.8% and 1290 Da, respectively. The supported PTA catalyst maintained high catalytic activity after three reuses, which indicated that the supported PTA catalyst had excellent catalytic activity and stable performance compared with the PTA catalyst.

MOF-derived metal oxide composite Mn2Co1Ox/CN for efficient formaldehyde oxidation at low temperature

2019 ◽  
Vol 9 (20) ◽  
pp. 5845-5854 ◽  
Author(s):  
Xi Wang ◽  
Jiawei Ying ◽  
Yuliang Mai ◽  
Junjie Zhang ◽  
Jiazhi Chen ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Low Temperature ◽  
Metal Oxide ◽  
Low Temperature Oxidation ◽  
Carbon Catalyst ◽  
Temperature Oxidation ◽  
Oxide Composite ◽  
Formaldehyde Oxidation

A novel MOF-derived MnCoOx nanoparticles embedded in porous N-doped carbon catalyst exhibits excellent catalytic activity for the low-temperature oxidation of formaldehyde.

Single-atom transition metals supported on black phosphorene for electrochemical nitrogen reduction

Nanoscale ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 4903-4908 ◽  
Author(s):  
Kang Liu ◽  
Junwei Fu ◽  
Li Zhu ◽  
Xiaodong Zhang ◽  
Hongmei Li ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Transition Metals ◽  
Reduction Reaction ◽  
Single Atom ◽  
High Catalytic Activity ◽  
Nitrogen Reduction ◽  
Mild Conditions ◽  
Black Phosphorene

Electrochemical nitrogen reduction reaction (NRR) is a promising route to produce ammonia under mild conditions. Single-atom W supported on BP was screened as a promising electrocatalyst with high catalytic activity, stability, and selectively for NRR.

Facile fabrication of a heterogeneous Co-modified pyridinecarboxaldehyde-polyethylenimine catalyst for efficient CO2 conversion under mild conditions

2020 ◽  
Vol 7 (5) ◽  
pp. 1140-1147
Author(s):  
Chao Liu ◽  
Li Yang ◽  
Jiaxu Zhang ◽  
Jianmin Sun
Keyword(s):  
Catalytic Activity ◽  
Ambient Temperature ◽  
High Catalytic Activity ◽  
Co2 Conversion ◽  
Mild Conditions ◽  
Active Metal ◽  
Facile Fabrication ◽  
Amine Groups

A heterogeneous Co-modified pyridinecarboxaldehyde-polyethylenimine catalyst with active metal sites and amine groups exhibited high catalytic activity for CO2 conversion under mild conditions, even at ambient temperature.

Tin sulfide and selenide clusters soluble in organic solvents with the core structures of Sn4S6 and Sn4Se6

2015 ◽  
Vol 44 (46) ◽  
pp. 19800-19804 ◽  
Author(s):  
Mingdong Zhong ◽  
Zhi Yang ◽  
Yafei Yi ◽  
Dongxiang Zhang ◽  
Kening Sun ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Organic Solvents ◽  
High Catalytic Activity ◽  
Tin Sulfide ◽  
Chalcogenide Clusters ◽  
Mild Conditions ◽  
The Core

Reactions of LSnCl (1) (L = N(2,6-iPr2C6H3)(SiMe3)) with sulfur and selenium, respectively under mild conditions yielded two tin chalcogenide clusters. The two products show high catalytic activity in ROP catalysis.

Sign in / Sign up

Export Citation Format

Share Document