scholarly journals Reaction Kinetics of Carbon Dioxide in Aqueous Diethanolamine Solutions Using the Stopped-Flow Technique

2012 ◽  
Vol 19 (1) ◽  
pp. 55-66 ◽  
Author(s):  
Marta Siemieniec ◽  
Hanna Kierzkowska-Pawlak ◽  
Andrzej Chacuk
Keyword(s):  
Carbon Dioxide ◽  
Reaction Kinetics ◽  
Rate Constants ◽  
Reaction Rate ◽  
Reaction Rate Constant ◽  
Stopped Flow ◽  
First Order ◽  
Pseudo First Order ◽  
Kinetics Of ◽  
Good Agreement

Reaction Kinetics of Carbon Dioxide in Aqueous Diethanolamine Solutions Using the Stopped-Flow Technique The pseudo-first-order rate constants (kOV) for the reactions between CO2 and diethanolamine have been studied using the stopped-flow technique in an aqueous solution at 293, 298, 303 and 313 K. The amine concentrations ranged from 167 to 500 mol·m-3. The overall reaction rate constant was found to increase with amine concentration and temperature. Both the zwitterion and termolecular mechanisms were applied to correlate the experimentally obtained rate constants. The values of SSE quality index showed a good agreement between the experimental data and the corresponding fit by the use of both mechanisms.

scholarly journals Reaction Kinetics of Carbon Dioxide in Aqueous Blends of N-Methyldiethanolamine and L-Arginine Using the Stopped-Flow Technique

Processes ◽  
2019 ◽  
Vol 7 (2) ◽  
pp. 81 ◽  
Author(s):  
Nafis Mahmud ◽  
Abdelbaki Benamor ◽  
Mustafa Nasser ◽  
Muftah H. El-Naas ◽  
Paitoon Tontiwachwuthikul
Keyword(s):  
Carbon Dioxide ◽  
Reaction Kinetics ◽  
Reaction Rate ◽  
Carbon Dioxide Emission ◽  
Solution Concentration ◽  
Reaction Rate Constant ◽  
Stopped Flow ◽  
Promoting Effect ◽  
Absolute Deviation ◽  
Kinetics Of

: Reduction of carbon dioxide emission from natural and industrial flue gases is paramount to help mitigate its effect on global warming. Efforts are continuously deployed worldwide to develop efficient technologies for CO2 capture. The use of environment friendly amino acids as rate promoters in the present amine systems has attracted the attention of many researchers recently. In this work, the reaction kinetics of carbon dioxide with blends of N-methyldiethanolamine and L-Arginine was investigated using stopped flow technique. The experiments were performed over a temperature range of 293 to 313 K and solution concentration up to one molar of different amino acid/amine ratios. The overall reaction rate constant (kov) was found to increase with increasing temperature and amine concentration as well as with increased proportion of L-Arginine concentration in the mixture. The experimental data were fitted to the zwitterion and termolecular mechanisms using a nonlinear regression technique with an average absolute deviation (AAD) of 7.6% and 8.0%, respectively. A comparative study of the promoting effect of L-Arginine with that of the effect of Glycine and DEA in MDEA blends showed that MDEA-Arginine blend exhibits faster reaction rate with CO2 with respect to MDEA-DEA blend, while the case was converse when compared to the MDEA-Glycine blend.

Kinetics of the Ozonation of Tetrabromobisphenol-A in Wastewater

2011 ◽  
Vol 383-390 ◽  
pp. 2945-2950 ◽  
Author(s):  
Jie Zhang ◽  
Shi Long He ◽  
Mei Feng Hou ◽  
Li Ping Wang ◽  
Li Jiang Tian
Keyword(s):  
Rate Constants ◽  
Apparent Rate Constant ◽  
Reaction Rate ◽  
Batch Reactor ◽  
Kinetic Studies ◽  
Tetrabromobisphenol A ◽  
First Order ◽  
Reaction Rate Constants ◽  
Pseudo First Order ◽  
Kinetics Of

The kinetics of TBBPA degradation by ozonation in semi-batch reactor was studied. The reaction rate constants of TBBPA with O3 and •OH were measured by means of direct ozone attack and competition kinetics, and the values of which were 6.10 l/(mol•s), 4.8×109 l/(mol•s), respectively. Results of kinetic studies showed that TBBPA degradation by ozonation under the different conditions tested followed the pseudo-first-order. The values of apparent rate constant of TBBPA degradation increased with the increase of ozone dosage and pH, but decreased with the increase of initial TBBPA concentration.

Reaction kinetics of carbon dioxide in aqueous blends of N-methyldiethanolamine and glycine using the stopped flow technique

2016 ◽  
Vol 33 ◽  
pp. 186-195 ◽  
Author(s):  
Abdelbaki Benamor ◽  
Mohammed Jaber Al-Marri ◽  
Majeda Khraisheh ◽  
Mustafa S. Nasser ◽  
Paitoon Tontiwachwuthikul
Keyword(s):  
Carbon Dioxide ◽  
Reaction Kinetics ◽  
Stopped Flow ◽  
Kinetics Of

scholarly journals The alcoholysis of 1,2,2-trimethylpropyl-methylfluorophosphonate

2000 ◽  
Vol 65 (12) ◽  
pp. 857-866
Author(s):  
Mladjen Micevic ◽  
Slobodan Petrovic
Keyword(s):  
Kinetic Data ◽  
Reaction Rate ◽  
Frequency Factor ◽  
Reaction Rate Constant ◽  
Order Reaction ◽  
Activation Entropy ◽  
Second Order Reaction ◽  
Third Order ◽  
First Order ◽  
Kinetics Of

The alcoholysis of 1,2,2-trimethylpropyl-methylfluorophosphonate (soman) was examined with a series of alkoxides and in corresponding alcohols: methanol, ethanol, 1-propanol, 2-propanol, 2-methoxyethanol and 2-ethoxyethanol. Soman reacts with the used alkoxides in a second order reaction, first order in each reactant. The kinetics of the reaction between 1,2,2-trimethylpropyl-methylfluorophosphonate and ethanol in the presence of diethylenetriamine was also examined. A third order reaction rate constant was calculated, first order in each reactant. The activation energy, frequency factor and activation entropy were determined on the basis of the kinetic data.

Kinetik der Reaktion von 2.4-Dinitrofluorbenzol mit Imidazol-, SH- und Imidazol-SH-Verbindungen / Kinetics of the Reaction of 2,4-dinitro-1-fluorobenzene with Imidazole-, SH- and Imidazole-SH-compounds

1971 ◽  
Vol 26 (10) ◽  
pp. 1010-1016 ◽  
Author(s):  
Renate Voigt ◽  
Helmut Wenck ◽  
Friedhelm Schneider
Keyword(s):  
Temperature Dependence ◽  
Rate Constants ◽  
Reaction Rate ◽  
Ph Dependence ◽  
First Order ◽  
Molecular Transfer ◽  
Thiolate Anion ◽  
Nucleophilic Reactivity ◽  
Kinetics Of ◽  
Lindley Equation

First order rate constants of the reaction of a series of SH-, imidazole- and imidazole/SH-compounds with FDNB as well as their pH- and temperature dependence were determined. Some of the tested imidazole/SH-compounds exhibit a higher nucleophilic reactivity as is expected on the basis of their pKSH-values. This enhanced reactivity is caused by an activation of the SH-groups by a neighbouring imidazole residue. The pH-independent rate constants were calculated using the Lindley equation.The kinetics of DNP-transfer from DNP-imidazole to SH-compounds were investigated. The pH-dependence of the reaction displays a maximum curve. Donor in this reaction is the DNP-imidazolecation and acceptor the thiolate anion.The reaction rate of FDNB with imidazole derivatives is two to three orders of magnitude slower than with SH-compounds.No inter- or intra-molecular transfer of the DNP-residue from sulfure to imidazole takes place.

On the Chemical Reactivity of the Phytochrome Chromophore in the Pr and Pfr Form

1985 ◽  
Vol 40 (3-4) ◽  
pp. 215-218 ◽  
Author(s):  
Fritz Thümmler ◽  
Peter Eilfeld ◽  
Wolfhart Rüdiger ◽  
Doo-Khil Moon ◽  
Pill-Soon Song
Keyword(s):  
Reaction Kinetics ◽  
Rate Constants ◽  
Chemical Reactivity ◽  
Order Reaction ◽  
First Order Reaction ◽  
Limiting Factor ◽  
Pseudo First Order Reaction ◽  
First Order ◽  
Pseudo First Order ◽  
The Difference

The reactivity of the phytochrome chromophore and related tetrapyrroles towards ozone and tetranitromethane was investigated. Both oxidizing reagents cause bleaching of the main absorp­tion band of the pigment. The rate constants for this bleaching were determined under conditions of pseudo first order reaction kinetics. The rate constants for the reaction with ozone are similar for native phytochrome and for freely accessible tetrapyrroles (biliverdin, small chromopeptides from phytochrome) indicating that accessibility is not the limiting factor for the reaction with ozone. Under a variety of conditions, the Pfr chromophore reacts by about 10% faster than the Pr chromophore. This may reflect the true difference in reactivity. The rate constants for the reaction with tetranitromethane are much larger for biliverdin, bilirubin and small chromopeptides from phytochrome than for native phytochrome. The limiting factor for this reaction in native phytochrome therefore is the accessibility of the chromophore by the reagent. Previous conclusions on the difference in exposure of the tetrapyrrole chromophore in Pr and Pfr are confirmed.

THE KINETICS OF THE DECOMPOSITION REACTIONS OF THE LOWER PARAFFINS: I. n-BUTANE

1938 ◽  
Vol 16b (5) ◽  
pp. 176-193 ◽  
Author(s):  
E. W. R. Steacie ◽  
I. E. Puddington
Keyword(s):  
Reaction Rate ◽  
High Pressures ◽  
The Other ◽  
First Order ◽  
Decomposition Reactions ◽  
Temperature And Pressure ◽  
Products Of Reaction ◽  
Kinetics Of ◽  
Good Agreement ◽  
Mechanism Of The Reaction

The kinetics of the thermal decomposition of n-butane has been investigated at pressures from 5 to 60 cm. and temperatures from 513 to 572 °C. The initial first order rate constants at high pressures are given by[Formula: see text]The results are in good agreement with the work of Frey and Hepp, but differ greatly from that of Paul and Marek. The reaction rate falls off strongly with diminishing pressure; this is rather surprising for a molecule as complex as butane. The first order constants in a given run fall rapidly as the reaction progresses. The last two facts suggest that chain processes may be involved.A large number of analyses of the products of reaction have been made at various pressures, temperatures, and stages of the reaction, the method being that of low-temperature fractional distillation. The products are virtually independent of temperature and pressure over the range investigated. The initial products, obtained by extrapolation to zero decomposition, are:—H2, 2.9; CH4, 33.9; C3H6, 33.9; C2H4, 15.2; C2H6, 14.1%. The mechanism of the reaction is discussed, and the results are compared with those of the other paraffin decompositions.

Degradation of propoxycarbazone-sodium with advanced oxidation processes

2011 ◽  
Vol 11 (1) ◽  
pp. 129-134 ◽  
Author(s):  
A. Dulov ◽  
N. Dulova ◽  
Y. Veressinina ◽  
M. Trapido
Keyword(s):  
Rate Constants ◽  
Advanced Oxidation Processes ◽  
Advanced Oxidation ◽  
Fenton Process ◽  
Oxidation Processes ◽  
First Order ◽  
Order Rate ◽  
Conversion Time ◽  
Pseudo First Order ◽  
Kinetics Of

The degradation of propoxycarbazone-sodium, an active component of commercial herbicide, in aqueous solution with ozone, UV photolysis and advanced oxidation processes: O3/UV, O3/UV/H2O2, H2O2/UV, and the Fenton process was studied. All these methods of degradation proved feasible. The kinetics of propoxycarbazone-sodium degradation in water followed the pseudo-first order equation for all studied processes except the Fenton treatment. The application of schemes with ozone demonstrated low pseudo-first order rate constants within the range of 10−4 s−1. Addition of UV radiation to the processes improved the removal of propoxycarbazone-sodium and increased the pseudo-first order rate constants to 10−3 s−1. The Fenton process was the most efficient and resulted in 5 and 60 s of half-life and 90% conversion time of propoxycarbazone-sodium, respectively, at 14 mM H2O2 concentration. UV treatment and the Fenton process may be recommended for practical application in decontamination of water or wastewater.

Mechanism of bromination of a quaternary pyrimidinium cation. Change of rate determining step with acidity

1978 ◽  
Vol 56 (23) ◽  
pp. 2970-2976 ◽  
Author(s):  
Oswald S. Tee ◽  
David C. Thackray ◽  
Charles G. Berks
Keyword(s):  
Kinetic Study ◽  
Rate Constants ◽  
Aqueous Media ◽  
Stopped Flow ◽  
Flow Method ◽  
High Acidity ◽  
Rate Determining Step ◽  
Kinetics Of ◽  
Good Agreement

The kinetics of bromination of the 1,2-dihydro-1,3-dimethyl-2-oxopyrimidinium cation (Q+) in aqueous media (pH 0–5) have been studied using the stopped-flow method. At the higher acidities (pH < 2) the results are consistent with rate determining attack by bromine upon the pseudobase (QOH), whereas at low acidities (pH > 4) it appears that pseudobase formation is rate determining. The change occurs because at high acidity the reversal of the pseudobase QOH to the cation is fast relative to bromine attack, whereas at low acidity the converse is true. Results obtained at intermediate acidities (pH 2–4) are consistent with this interpretation.A separate kinetic study of pseudobase formation (and decomposition) yielded rate constants in good agreement with those derived from the bromination study.

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