Acceleration of Ammonium Nitrite Denitrification by Freezing: Determination of Activation Energy from the Temperature of Maximum Reaction Rate

2011 ◽  
Vol 115 (50) ◽  
pp. 14446-14451 ◽  
Author(s):  
Norimichi Takenaka ◽  
Itaru Takahashi ◽  
Hiroshi Suekane ◽  
Koji Yamamoto ◽  
Yasuhiro Sadanaga ◽  
...  
Keyword(s):  
Activation Energy ◽  
Reaction Rate ◽  
Maximum Reaction Rate ◽  
Maximum Reaction

Kinetic Analysis of the Decomposition of Calcium Carbonate Using Danyang Limestone

2006 ◽  
Vol 510-511 ◽  
pp. 502-505 ◽  
Author(s):  
Sang Hwan Cho ◽  
Sung Min Joo ◽  
Jin Sang Cho ◽  
Young Hwan Yu ◽  
Ji Whan Ahn ◽  
...  
Keyword(s):  
Activation Energy ◽  
Calcium Carbonate ◽  
Kinetic Parameter ◽  
Kinetic Analysis ◽  
Heating Rate ◽  
Reaction Rate ◽  
Decomposition Temperature ◽  
Final Point ◽  
Maximum Reaction

Non-isothermal behaviors of calcium carbonate using Danyang limestone were investigated. It was attempted to provide non-isothermal data with a precision sufficient for the determination of reliable decomposition behaviors and for the estimation of accurate kinetic parameter. The decomposition temperature of calcium carbonate on the onset, peak and final point were measured. Reaction rate was decreased and maximum reaction temperature was increased with increasing heating rate. Activation energy of Danyang limestone was 45.14㎉/㏖ and 50.80㎉/ ㏖ by Kissinger method and Freeman method, respectively.

scholarly journals Modelling and Multi-Objective Optimization of the Sulphur Dioxide Oxidation Process

Processes ◽  
2021 ◽  
Vol 9 (6) ◽  
pp. 1072
Author(s):  
Mohammad Reza Zaker ◽  
Clémence Fauteux-Lefebvre ◽  
Jules Thibault
Keyword(s):  
Sulphuric Acid ◽  
Sulphur Dioxide ◽  
Variable Number ◽  
Inlet Temperature ◽  
Multi Objective Optimization ◽  
Absorption Column ◽  
Maximum Reaction Rate ◽  
Multi Objective ◽  
Maximum Reaction

Sulphuric acid (H2SO4) is one of the most produced chemicals in the world. The critical step of the sulphuric acid production is the oxidation of sulphur dioxide (SO2) to sulphur trioxide (SO3) which takes place in a multi catalytic bed reactor. In this study, a representative kinetic rate equation was rigorously selected to develop a mathematical model to perform the multi-objective optimization (MOO) of the reactor. The objectives of the MOO were the SO2 conversion, SO3 productivity, and catalyst weight, whereas the decisions variables were the inlet temperature and the length of each catalytic bed. MOO studies were performed for various design scenarios involving a variable number of catalytic beds and different reactor configurations. The MOO process was mainly comprised of two steps: (1) the determination of Pareto domain via the determination a large number of non-dominated solutions, and (2) the ranking of the Pareto-optimal solutions based on preferences of a decision maker. Results show that a reactor comprised of four catalytic beds with an intermediate absorption column provides higher SO2 conversion, marginally superior to four catalytic beds without an intermediate SO3 absorption column. Both scenarios are close to the ideal optimum, where the reactor temperature would be adjusted to always be at the maximum reaction rate. Results clearly highlight the compromise existing between conversion, productivity and catalyst weight.

Determination of the reaction rate constant and activation energy for pressure-induced 2+2 cycloaddition of the C60 fullerene

2002 ◽  
Vol 44 (3) ◽  
pp. 557-559 ◽  
Author(s):  
V. A. Davydov ◽  
L. S. Kashevarova ◽  
A. V. Rakhmanina ◽  
V. M. Senyavin ◽  
N. N. Oleinikov ◽  
...  
Keyword(s):  
Activation Energy ◽  
Rate Constant ◽  
Reaction Rate ◽  
Reaction Rate Constant ◽  
C60 Fullerene

Biodegradation of 2,4-dichlorophenol in a fluidized bed reactor with immobilized Phanerochaete chrysosporium

2010 ◽  
Vol 62 (4) ◽  
pp. 947-955 ◽  
Author(s):  
Xiao-ming Li ◽  
Qi Yang ◽  
Ying Zhang ◽  
Wei Zheng ◽  
Xiu Yue ◽  
...  
Keyword(s):  
Fluidized Bed ◽  
Phanerochaete Chrysosporium ◽  
Reaction Rate ◽  
Immobilized Cells ◽  
Fluidized Bed Reactor ◽  
Degradation Process ◽  
Maximum Reaction Rate ◽  
Monod Equation ◽  
Continuous Bioreactor ◽  
Maximum Reaction

The performance of a fluidized bed reactor using immobilized Phanerochaete chrysosporium to remove 2,4-dichlorophenol (2,4-DCP) from aqueous solution was investigated. The contribution of lignin peroxidase (LiP) and manganese peroxidase (MnP) secreted by Phanerochaete chrysosporium to the 2,4-DCP degradation was examined. Results showed that Lip and Mnp were not essential to 2,4-DCP degradation while their presence enhanced the degradation process and reaction rate. In sequential batch experiment, the bioactivity of immobilized cells was recovered and improved during the culture and the maximum degradation rate constant of 13.95 mg (Ld)−1 could be reached. In continuous bioreactor test, the kinetic behavior of the Phanerochaete chrysosporium immobilized on loofa sponge was found to follow the Monod equation. The maximum reaction rate was 7.002 mg (Lh)−1, and the saturation constant was 26.045 mg L−1.

Basic Studies on Anaerobic Degradation of Glucose in Continuous Stirred Tank Reactors

1991 ◽  
Vol 24 (5) ◽  
pp. 141-147
Author(s):  
Michimasa Nakamura ◽  
Atsushi Sakai ◽  
Jun'ichiro Matsumoto
Keyword(s):  
Anaerobic Degradation ◽  
Volatile Fatty Acid ◽  
Reaction Rate ◽  
Ph Value ◽  
Reaction Rate Constant ◽  
The Other ◽  
Total Volatile ◽  
Maximum Reaction Rate ◽  
Maximum Reaction ◽  
Total Volatile Fatty Acid

The two series of the characteristics of anaerobic degradation of low glucose concentrations were investigated. In the first series, the pH value in each reactor was not controlled. In the second series, the pH value in each reactor was controlled in the range of 6.9–7.2, by adding sodium bicarbonate into each influent. The ORP value was depressed by controlling the pH value of each reactor from acid range to approximately neutral range. In the pH uncontrolled series, the pH value in outflow decreased with increasing glucose concentration. In the pH uncontrolled series, produced total volatile fatty acid was about 70 to 550 mg/l; on the other hand, in pH controlled series, produced total volatile fatty acid was about 50 mg/l to 350 mg/l. The highest concentrations of acids formed were acetic acids, the second highest formed were propionic acids, the last formed were butyric acids. In the pH uncontrolled series, the maximum reaction rate constant Vm was 0.749 gCOD/gVS · day and the saturation constant Ks = 0.435 g/l. On the other hand, in the pH controlled series, the maximum reaction rate constant Vm was 1.441 gCOD/gVS · day and the saturation constant Ks = 0.739 g/l. Thus by controlling the pH value of the reactor, the activities of the anaerobic bacteria were much enhanced.

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