Structure effects in oxidation of aliphatic ketones by thallium(III) sulphate

1983 ◽  
Vol 48 (10) ◽  
pp. 2819-2824 ◽  
Author(s):  
Miroslav Pechál ◽  
Milan Strašák
Keyword(s):  
Steric Effects ◽  
Uv Spectrophotometry ◽  
Order Kinetic ◽  
Structural Factors ◽  
Rate Determining Step ◽  
First Order Kinetics ◽  
Aliphatic Ketones ◽  
Kinetics Of ◽  
Enol Formation ◽  
Order Kinetic Equation

Oxidation kinetics of 11 aliphatic ketones (R1COR2) by thallium(III) sulphate in dilute sulphuric acid have been studied by UV spectrophotometry. The oxidation of methylalkylketones (R2 > CH3) follows the first order kinetics, that of higher dialkyl ketones (R1, R2 > CH3) obeys the second order kinetic equation. Polar and steric effects in the oxidation of aliphatic ketones have been separated by application of LFER to the chosen sets of methyl alkyl ketones (R2 > CH3) and dialkyl ketones (R1, R2 > CH3). Structural factors have a certain effect on the oxidation rate of methyl alkyl ketones, the changes in the reaction rate being ascribable almost exclusively to steric effects of the R2 substituents. The polar effects are very important in the oxidation of dialkyl ketones. Results of the application of LFER suggest that enol formation is the rate-determining step in the oxidations of the two sets of ketones.

scholarly journals KINETICS OF REACTION BETWEEN MALACHITE GREEN AND HYDROXYL ION IN THE PRESENCE OF REDUCING SUGARS

2015 ◽  
Vol 23 (23) ◽  
pp. 61-72
Author(s):  
Dayo Felix Latona ◽  
Adewumi Oluwasogo Dada
Keyword(s):  
Malachite Green ◽  
Activation Parameters ◽  
Cell Compartment ◽  
First Order ◽  
Rate Determining Step ◽  
First Order Kinetics ◽  
Hydroxyl Ion ◽  
Kinetics Of Reaction ◽  
Kinetics Of ◽  
Sphere Mechanism

The reaction was studied via pseudo-first-order kinetics using a UV-1800 Shimadzu spectrophotometer with a thermostated cell compartment and interfaced with a computer. The reaction showed first order with respect to malachite green and sugar and hydroxyl ion concentrations. However, the reaction was independent of ionic strength and showed no dependence on the salt effect, indicating an inner sphere mechanism for the reaction. There was no polymerization of the reaction mixture with acrylonitrile, indicating the absence of radicals in the course of the reaction. Michaelis-Menten plot indicated the presence of a reaction intermediate in the rate-determining step. The activation parameters of the reaction have been calculated and products were elucidated by FTIR spectroscopy. The stoichiometry of the reaction is 1:1. A mechanism consistent with the above facts has been suggested.

H2O2-assisted photolysis of reactive dye BES golden yellow simulated wastewater

2009 ◽  
Vol 60 (9) ◽  
pp. 2329-2336 ◽  
Author(s):  
Lv Jian-xiao ◽  
Xie Guo-hong ◽  
Yue Qing-ling ◽  
Zhang Li ◽  
Li Jian-min ◽  
...  
Keyword(s):  
Reactive Dye ◽  
Order Kinetic ◽  
Yellow Solution ◽  
Golden Yellow ◽  
Optimum Ph ◽  
Initial Ph ◽  
Simulated Wastewater ◽  
Kinetics Of ◽  
H2o2 Addition ◽  
Order Kinetic Equation

Reactive dye BES golden yellow simulated wastewater was treated with H2O2-assisted photolysis method. Influences of factors such as reaction time, initial pH and H2O2 dosage were investigated, and the reaction kinetics of the process were explored. Results showed that, the degradation of 200 mg/L BES golden yellow solution happened only in the presence of both conditions: UV irradiation and H2O2 addition. Initial pH and H2O2 dosage had remarkable influence on the removal efficiency of the dye. Through several groups of univariate experiments, the optimum pH and H2O2 dosage of the photolysis process were found to be 6–7 and 0.0375 mL 30% H2O2 per milligram of BES golden yellow, respectively. The photolysis process was approximately in accordance with the second-order kinetic equation.

Adsorption Kinetics of Phosphate on Ceria-Based Adsorbent

2013 ◽  
Vol 726-731 ◽  
pp. 1668-1672
Author(s):  
Bin Li ◽  
Hong Bin Wang ◽  
Yan Yuan
Keyword(s):  
Kinetic Equation ◽  
Influencing Factors ◽  
Adsorption Kinetics ◽  
Adsorption Process ◽  
Close Relation ◽  
Phosphate Adsorption ◽  
Order Kinetic ◽  
Adsorbent Surface ◽  
Kinetics Of ◽  
Order Kinetic Equation

The adsorption kinetics and influencing factors deduction showed that adsorption process accorded with a second-order kinetic equation according to academic hypothesis. The result was validated by the phosphate adsorption onto Veria-Based adsorbent. The factor (m/V)bhad the close relation with the adsorption speed and the adsorbent dosage, intensity exponent b=0.44 (0b1) in this test condition. All the results show that phosphate adsorption on the adsorbent surface was mono-layer chemisorptions and that the hypothesis of kinetic inference was reasonable.

scholarly journals Decoloration of methylene blue simulated wastewater using a UV-H2O2 combined system

2011 ◽  
Vol 1 (1) ◽  
pp. 45-51 ◽  
Author(s):  
L. V. Jian-xiao ◽  
Cui Ying ◽  
Xie Guo-hong ◽  
Zhou Ling-yun ◽  
Wang Su-fen
Keyword(s):  
Methylene Blue ◽  
Ph Value ◽  
Order Kinetic ◽  
Combined System ◽  
Initial Stage ◽  
Optimum Ph ◽  
Initial Ph ◽  
Simulated Wastewater ◽  
Kinetics Of ◽  
Order Kinetic Equation

Methylene blue simulated wastewater was treated with a UV-H2O2 combined system. Influences of factors such as reaction time, initial pH value and H2O2 dosage were investigated, and the reaction kinetics of the process was explored. Results showed that the degradation of methylene blue happened only in the presence of both conditions: UV irradiation and H2O2 addition. Initial pH and H2O2 dosage had a remarkable influence on the degradation efficiency. Through several groups of univariate experiments, the optimum pH and H2O2 dosage of the photolysis process were found to be 4–5 and 0.165 mL 30% H2O2 per milligram of methylene blue, respectively. The photolysis process was relatively fast at the initial stage and, 20 min later, it was approximately in accordance with the first-order kinetic equation.

scholarly journals SYNTHESIS AND STUDY OF THE REACTION KINETICS OF HOMOVERATRILAMINE WITH BRASSYLIC ACID BY HPLC

2020 ◽  
Vol 9 (10) ◽  
pp. 1-7
Keyword(s):  
High Performance ◽  
Condensation Reaction ◽  
High Performance Liquid Chromatographic ◽  
Order Kinetic ◽  
First Order ◽  
Liquid Chromatographic Separation ◽  
Brassylic Acid ◽  
Liquid Chromatographic ◽  
Kinetics Of ◽  
Order Kinetic Equation

In this work, amide, isoquinoline were synthesized and the kinetics of the reaction of homoveratrylamine with brassilic acid was studied by HPLC. The conditions of (high-performance liquid) chromatographic separation were revealed, which allow satisfactory separation of the components of the reaction mixture consisting of reagents, intermediates and products of the reactions of condensation and cyclization. By studying the kinetic laws, it was found that the reactions of condensation and cyclization obey the first-order kinetic equation and the activation energy is, respectively, 172.3 kJ / mol for the amide condensation reaction, and 118.8 kJ / mol for the cyclization reaction.

Adsorption Kinetics of Direct Red 4BS Using Stove Ash

2013 ◽  
Vol 726-731 ◽  
pp. 2833-2836
Author(s):  
Bo Yu ◽  
Wei Ming Wang ◽  
Di Ma ◽  
Zai Sheng Cai
Keyword(s):  
Kinetic Equation ◽  
Kinetic Parameters ◽  
Adsorption Kinetics ◽  
Waste Material ◽  
Order Kinetic ◽  
Initial Concentration ◽  
Adsorption Reaction ◽  
Pseudo Second Order ◽  
Kinetics Of ◽  
Order Kinetic Equation

A waste material, stove ash, was applied to adsorbthe Direct Red 4BS. The dye amount absorbed by ash was improved with increasingthe dye initial concentration from 3g/Lto 7g/L. Dye was adsorbed within 2minutes and the equilibrium was achieved after 5 minutes. The kinetic of adsorptionreaction was also studied. The results showed that adsorption reaction was congruentwith Lagergren pseudo-second order kinetic equation, and different initial dyeconcentrations had their specific kinetic parameters.

Degradation of biotansformation products of nonylphenol ethoxylates by ozonation and UV/TiO2 treatment

2002 ◽  
Vol 46 (11-12) ◽  
pp. 127-132 ◽  
Author(s):  
M. Ike ◽  
M. Asano ◽  
F.D. Belkada ◽  
S. Tsunoi ◽  
M. Tanaka ◽  
...  
Keyword(s):  
Degradation Rate ◽  
Degradation Kinetics ◽  
Chemical Oxidation ◽  
Order Kinetic ◽  
Oxidation Processes ◽  
First Order ◽  
First Order Kinetics ◽  
Biotransformation Products ◽  
Kinetics Of ◽  
Dioxide Suspension

The degradation kinetics of biotransformation products of nonylphenol polyethoxylates (NPEOs), nonylphenol (NP), nonylphenol monoethoxylate (NP1EO) and nonylphenoxy carboxylic acid (NP1EC), by ozonation and UV/TiO2 (ultraviolet photocatalytic degradation in the presence of titanium dioxide suspension as a catalyst) were investigated using lab-scale reactors. The degradation rate of NP by UV/TiO2 was the highest among the tested NPEOs metabolites, while NP1EC showed the lowest degradation rate. In contrast, ozonation was especially effective for the breakdown of NP1EC. NP could be also degraded efficiently by ozonation, however, it was much less effective for NP1EO decomposition. Degradation of NP by both chemical oxidation processes followed first-order kinetics. The degradation curves of NP1EO and NP1EC could be approximately described by first-order kinetics also, although the degradation of NP1EC by ozonation seemed to follow a second-order kinetic.

Kinetic of oxidation of methyl orange by vanadium(V) under conditions VO2+ and decavanadates coexist: Catalysis by Triton X-100 micellar medium

2019 ◽  
Author(s):  
Chem Int
Keyword(s):  
Methyl Orange ◽  
Solution Ph ◽  
Vanadium Concentration ◽  
Limiting Behavior ◽  
First Order ◽  
First Order Kinetics ◽  
Ph Range ◽  
Kinetic Pattern ◽  
Triton X ◽  
Kinetics Of

The kinetics of oxidation of methyl orange by vanadium(V) {V(V)} has been investigated in the pH range 2.3-3.79. In this pH range V(V) exists both in the form of decavanadates and VO2+. The kinetic results are distinctly different from the results obtained for the same reaction in highly acidic solution (pH < 1) where V(V) exists only in the form of VO2+. The reaction obeys first order kinetics with respect to methyl orange but the rate has very little dependence on total vanadium concentration. The reaction is accelerated by H+ ion but the dependence of rate on [H+] is less than that corresponding to first order dependence. The equilibrium between decavanadates and VO2+ explains the different kinetic pattern observed in this pH range. The reaction is markedly accelerated by Triton X-100 micelles. The rate-[surfactant] profile shows a limiting behavior indicative of a unimolecular pathway in the micellar pseudophase.

Kinetics of carbon monoxide methanation on a Ni/SiO2 catalyst

1990 ◽  
Vol 55 (7) ◽  
pp. 1678-1685
Author(s):  
Vladimír Stuchlý ◽  
Karel Klusáček
Keyword(s):  
Carbon Monoxide ◽  
Reaction Rate ◽  
Catalyst Activity ◽  
Adsorbed Hydrogen ◽  
Reaction Products ◽  
Co Methanation ◽  
Molar Ratios ◽  
Rate Determining Step ◽  
Higher Temperature ◽  
Kinetics Of

Kinetics of CO methanation on a commercial Ni/SiO2 catalyst was evaluated at atmospheric pressure, between 528 and 550 K and for hydrogen to carbon monoxide molar ratios ranging from 3 : 1 to 200 : 1. The effect of reaction products on the reaction rate was also examined. Below 550 K, only methane was selectively formed. Above this temperature, the formation of carbon dioxide was also observed. The experimental data could be described by two modified Langmuir-Hinshelwood kinetic models, based on hydrogenation of surface CO by molecularly or by dissociatively adsorbed hydrogen in the rate-determining step. Water reversibly lowered catalyst activity and its effect was more pronounced at higher temperature.

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