Oxidation of α-Pinene with Hydrogen Peroxide Catalyzed by VO(OAc)2

2012 ◽  
Vol 550-553 ◽  
pp. 179-182
Author(s):  
Min Zheng ◽  
Jian Sheng Tang ◽  
Du Lin Yin ◽  
Qiong Xu
Keyword(s):  
Hydrogen Peroxide ◽  
Catalytic Activity ◽  
Atmospheric Pressure ◽  
Product Selectivity ◽  
Reaction Products ◽  
Campholenic Aldehyde ◽  
Ethylene Glycol Dimethyl Ether ◽  
Major Reaction ◽  
Catalyst Dosage ◽  
Influence Of Solvent

The oxidation of α-pinene with hydrogen peroxide, at 40°C and atmospheric pressure, using ethylene glycol dimethyl ether as solvent was carried out in the presence of VO(OAc)2. The influence of solvent, reaction temperature and catalyst dosage on catalytic activity and product selectivity was studied. The major reaction products were verbenon (45.9% selectivity at 82.9% conversion). Formation of campholenic aldehyde, myrtenal, verbenol and epoxypinane was also observed.

Chemical Reactions at the in Vacuo Au/Inp Interface

1986 ◽  
Vol 83 ◽  
Author(s):  
R. Stanley Williams ◽  
C. Thomas Tsai ◽  
Eun-Hee Cirlin
Keyword(s):  
Intermetallic Compound ◽  
Atmospheric Pressure ◽  
High Vacuum ◽  
Thermodynamic System ◽  
External Pressure ◽  
Ultra High Vacuum ◽  
Reaction Products ◽  
Inp Substrate ◽  
Major Reaction ◽  
Closed Thermodynamic System

ABSTRACTThe reaction between a Au film and an Inp substrate occurs much more readily in vacuo than under an external pressure of an inert ga. At atmospheric pressure, the compounds Au2P3 and the γ intermetallic compound (at times designated Au7In3, Au9In4, or Au2In) are formed at 450 °C and remain fairly stable even when annealed at 500°C for hours. Under ultra-high vacuum conditions, phosphorous readily escapes from the film when a sample is annealed at 300°C for 15 minutes, and the major reaction products are the ψ phase (Au3In2) and another intermetallic compound that is probably AuIn. The presence of an inert gas creates a kinetic barrier for the escape of phosphorous from the surface, and thus Au/InP behaves more like a closed thermodynamic system under pressure than in a vacuum.

Decomposition of hydrogen peroxide on a two-component NiO-CdO catalyst and the effect of ionizing radiation on its catalytic properties

1979 ◽  
Vol 44 (4) ◽  
pp. 1015-1022 ◽  
Author(s):  
Viliam Múčka
Keyword(s):  
Aqueous Solution ◽  
Hydrogen Peroxide ◽  
Catalytic Activity ◽  
Nickel Oxide ◽  
Catalytic Properties ◽  
Cadmium Oxide ◽  
Chemisorb Oxygen ◽  
Composition Region ◽  
Chemisorbed Oxygen ◽  
Two Component

The catalytic properties of two-component catalyst nickel oxide-cadmium oxide with the proportions of the components covering the whole composition region 0-100% were examined by studying the decomposition of hydrogen peroxide in aqueous solution on it. In the range 0-25 mol.% CdO, cadmium oxide is found to affect infavourably the ability of nickel oxide to chemisorb oxygen. The amount of the chemisorbed oxygen increases several times on gamma irradiation of the samples. The effect of cadmium oxide on the catalytic activity of the system shows up in fresh samples only indirectly via the changed amount of the oxygen chemisorbed. In older samples the initial catalytic activity of the system is changed, which can be explained based on the concept of bivalent catalytic centres in terms of the co-action of the catalytic centres of the two oxides, which are in equilibrium. The irradiation of the system under study speeds up the processes leading to the establishing of this equilibrium which is thermally very stable, and results in a substantial increase of the catalytic activity of the samples investigated.

Hydrogen peroxide decomposition on a two-component CuO-Cr2O3 catalyst

1988 ◽  
Vol 53 (8) ◽  
pp. 1636-1646 ◽  
Author(s):  
Viliam Múčka ◽  
Kamil Lang
Keyword(s):  
Hydrogen Peroxide ◽  
Catalytic Activity ◽  
Extreme Values ◽  
Catalytic Properties ◽  
Active Components ◽  
Catalytic Systems ◽  
Heterogeneous Catalytic ◽  
Peroxide Decomposition ◽  
Two Component ◽  
Catalytically Active

Some physical and catalytic properties of the two-component copper(II)oxide-chromium(III)oxide catalyst with different content of both components were studied using the decomposition of the aqueous solution of hydrogen peroxide as a testing reaction. It has been found that along to both basic components, the system under study contains also the spinel structure CuCr2O4, chromate washable by water and hexavalent ions of chromium unwashable by water. The soluble chromate is catalytically active. During the first period of the reaction the equilibrium is being established in both homogeneous and heterogeneous catalytic systems. The catalytic activity as well as the specific surface area of the washed solid is a non-monotonous function of its composition. It seems highly probable that the extreme values of both these quantities are not connected with the detected admixtures in the catalytic system. The system under study is very insensitive with regard to the applied doses of gamma radiation. Its catalytic properties are changed rather significantly after the thermal treatment and particularly after the partial reduction to low degree by hydrogen. The observed changes of the catalytic activity of the system under study are very probably in connection with the changes of the valence state of the catalytically active components of the catalyst.

Kinetics of the catalytic hydrodesulphurization reaction system; hydrogenolysis of thiophene

1980 ◽  
Vol 45 (10) ◽  
pp. 2728-2741 ◽  
Author(s):  
Pavel Fott ◽  
Petr Schneider
Keyword(s):  
Atmospheric Pressure ◽  
Active Sites ◽  
Flow Reactor ◽  
Kinetic Equations ◽  
Reaction System ◽  
Reaction Products ◽  
Molybdenum Catalyst ◽  
Cobalt Molybdenum Catalyst ◽  
Kinetics Of ◽  
Reaction Schemes

Kinetics have been studied of the reaction system taking place during the reaction of thiophene on the cobalt-molybdenum catalyst in a gradientless circulation flow reactor at 360 °C and atmospheric pressure. Butane has been found present in a small amount in the reaction products even at very low conversion. In view of this, consecutive and parallel-consecutive (triangular) reaction schemes have been proposed. In the former scheme the appearance of butane is accounted for by rate of desorption of butene being comparable with the rate of its hydrogenation. According to the latter scheme part of the butane originates from thiophene via a different route than through hydrogenation of butene. Analysis of the kinetic data has revealed that the reaction of thiophene should be considered to take place on other active sites than that of butene. Kinetic equations derived on this assumption for the consecutive and the triangular reaction schemes correlate experimental data with acceptable accuracy.

scholarly journals Study of the Synchrotron Photoionization Oxidation of Alpha-Angelica Lactone (AAL) Initiated by O(3P) at 298, 550, and 700 K

Molecules ◽  
2021 ◽  
Vol 26 (13) ◽  
pp. 4070
Author(s):  
Golbon Rezaei ◽  
Giovanni Meloni
Keyword(s):  
Atomic Oxygen ◽  
Fossil Fuels ◽  
Reaction Products ◽  
Photoionization Mass Spectrometry ◽  
Natural Substances ◽  
Primary Products ◽  
Major Reaction ◽  
Angelica Lactone ◽  
Significant Attention

In recent years, biofuels have been receiving significant attention because of their potential for decreasing carbon emissions and providing a long-term renewable solution to unsustainable fossil fuels. Currently, lactones are some of the alternatives being produced. Many lactones occur in a range of natural substances and have many advantages over bioethanol. In this study, the oxidation of alpha-angelica lactone initiated by ground-state atomic oxygen, O(3P), was studied at 298, 550, and 700 K using synchrotron radiation coupled with multiplexed photoionization mass spectrometry at the Lawrence Berkeley National Lab (LBNL). Photoionization spectra and kinetic time traces were measured to identify the primary products. Ketene, acetaldehyde, methyl vinyl ketone, methylglyoxal, dimethyl glyoxal, and 5-methyl-2,4-furandione were characterized as major reaction products, with ketene being the most abundant at all three temperatures. Possible reaction pathways for the formation of the observed primary products were computed using the CBS–QB3 composite method.

Enhanced Long-Term Color Stability of Teeth Treated with Hydrogen Peroxide and Non-Thermal Atmospheric Pressure Plasma Jets

2014 ◽  
Vol 11 (11) ◽  
pp. 1010-1017 ◽  
Author(s):  
Seoul Hee Nam ◽  
Hyun Wook Lee ◽  
Jin Woo Hong ◽  
Hae June Lee ◽  
Gyoo Cheon Kim
Keyword(s):  
Hydrogen Peroxide ◽  
Atmospheric Pressure ◽  
Atmospheric Pressure Plasma ◽  
Color Stability ◽  
Plasma Jets ◽  
Pressure Plasma

Vanadium-Chromium Oxide: Effective Catalysts for Ammoxidation of 3-Picoline

2013 ◽  
Vol 634-638 ◽  
pp. 624-627 ◽  
Author(s):  
Feng Jiang ◽  
Wei Xu ◽  
Lei Niu ◽  
Guo Min Xiao
Keyword(s):  
Raman Spectroscopy ◽  
Catalytic Activity ◽  
Chromium Oxide ◽  
Atmospheric Pressure ◽  
High Selectivity ◽  
Surface Acidity ◽  
N2 Adsorption ◽  
Composite Oxide ◽  
Highly Active

Bulk vanadium-chromium oxide (VCrO) catalyst was prepared and characterized by N2 adsorption, XRD, NH3-TPD, H2-TPR, and Raman spectroscopy. XRD and Raman results showed that the VCrO catalyst was a kind of VV-CrIII composite oxide mainly consisted of crystalline V2O5 and CrVO4-Ⅲ (orthorhombic). NH3-TPD and H2-TPR results revealed that this catalyst had negligible surface acidity, and was easily reduced due to the formation of CrVO4-Ⅲ. Their catalytic activity was evaluated in the ammoxidation of 3-picoline to nicotinonitrile. Catalytic results showed that the bulk VCrO catalyst was highly active and selective; the nicotinonitrile selectivity and yield was up to 96.1%, 88.2% respectively at atmospheric pressure and 360 °C. The high selectivity was related closely to the low surface acidity of the catalyst.

Kinetics Studies for Catalytic Oxidation of Methyl Orange over the Heterogeneous Fe/Beta Catalysts

2013 ◽  
Vol 807-809 ◽  
pp. 361-364
Author(s):  
Fang Guo ◽  
Jun Qiang Xu ◽  
Jun Li
Keyword(s):  
Activation Energy ◽  
Hydrogen Peroxide ◽  
Reaction Mechanism ◽  
Methyl Orange ◽  
Incipient Wetness Impregnation ◽  
Kinetics Studies ◽  
Optimum Reaction ◽  
Catalyst Dosage ◽  
Oxidation Degradation ◽  
Degradation Of Methyl Orange

The Fe/Beta catalysts were prepared by conventional incipient wetness impregnation. The catalysis oxidation degradation of methyl orange was carried out in catalyst and H2O2 process. The results indicated that the catalyst and hydrogen peroxide were more benefit to degradation of methyl orange. The reaction condition was optimized. The optimum reaction process was as follow: iron amount of catalyst was 1.25%, the catalyst dosage and H2O2 concentration was 1 mg/L and 1.5 mg/L, and reaction temperature was 70 °C. The apparent activation energy (65 KJ/mol) was obtained according to the arrhenius formula, which was benefit to study the reaction mechanism.

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