Development of an Activity Based Kinetic Model for an Esterification Process with Indion 180 Catalyst

2019 ◽  
Vol 17 (9) ◽  
Author(s):  
Mekala Mallaiah ◽  
Chimmiri Venkateswarlu
Keyword(s):  
Kinetic Model ◽  
Reaction Rate ◽  
Experimental Results ◽  
Catalyst Loading ◽  
Esterification Reaction ◽  
Order Kinetic ◽  
Kinetic Rate ◽  
Model Predictions ◽  
Effects Of Temperature ◽  
Kinetics Of

Abstract The kinetics of esterification reaction between acetic acid and methanol was studied with the Indion 180 catalyst in the temperature range between 323.15 and 353.15K, and the catalyst loading between 0.01 g/cc to0.05 g/cc. The effects of temperature, catalyst loading, size of the catalyst and agitation speed on the reaction rate were investigated. The experimental results have shown the negligible effect of mass transfer resistances on the reaction rate. A second order kinetic rate expression was used to correlate the experimental data. An activity based kinetic model was also developed for the esterification process, which was validated against experimental results. The activity based model is found advantageous as it involves only two reaction rate parameters which were determined based on the kinetic rate parameters of the concentration based model. The comparison of the model predictions with the experimental results for different temperature and catalyst loading conditions has shown the better suitability of the activity based kinetic model for the esterification process with Indion 180 catalyst.

Kinetics of Reductive Dechlorination of DDT in Soil with Zero-Valent Iron

2011 ◽  
Vol 295-297 ◽  
pp. 1236-1239
Author(s):  
Yin Hai Lang ◽  
Min Jie Wang ◽  
Nan Nan Wang
Keyword(s):  
Kinetic Model ◽  
Reductive Dechlorination ◽  
Reaction Rate ◽  
Zero Valent Iron ◽  
Order Kinetic ◽  
First Order ◽  
Reaction Rate Constants ◽  
Order Kinetic Model ◽  
Pseudo First Order ◽  
Kinetics Of

In this study, reductive dechlorination of DDT compounds by zero-valent iron in Jiangxi red soil was investigated. DDT compounds were effectively dechlorinated by zero-valent iron. The pseudo-first-order kinetic model for 2,4¢-DDT and 4,4¢-DDT reduction with zero-valent iron was proposed. The reaction rate constants for 2,4¢-DDT and 4,4¢-DDT were 1.19´10-2(min-1) and 1.44´10-2(min-1), respectively. The dechlorination of 2,4¢-DDT and 4,4¢-DDT were mainly affected by the specific surface area of iron. The data from the variable-pH experiments (between 3.6 and 8.8) suggested that pH does not play a role in the rate-determination step.

scholarly journals Kinetic modeling of canola oil transesterification catalyzed by quicklime

2018 ◽  
Vol 16 (6) ◽  
Author(s):  
J.N. Camacho ◽  
G. E. Galván Muciño ◽  
S.L. Martínez Vargas ◽  
C. Pérez Alonso ◽  
R. Natividad
Keyword(s):  
Experimental Data ◽  
Kinetic Model ◽  
Canola Oil ◽  
Reaction Rate ◽  
Molar Ratio ◽  
Catalyst Loading ◽  
Minor Effect ◽  
Whole Process ◽  
High Effect ◽  
Kinetics Of

This work aimed to study and model the kinetics of transesterification of canola oil with methanol catalyzed by calcined quicklime (CaO + MgO). The influence of three main variables was studied at 328 K: reagents order addition (has a negligible effect on the reaction), methanol-oil molar ratio (has minor effect on reaction rate after 1.5 h of reaction) and catalyst loading (high effect on reaction rate) to achieve at least a triglycerides conversion of 96.5% in concordance with norm EN 14103. A kinetic model based on an Eley-Rideal mechanism was found to well fit (R2 = 0.9886) the experimental data. Thus, it was concluded that for the quicklime catalyzed transesterification of canola oil with methanol to occur, first the methanol must be chemisorbed and the resulting methoxy species react with triglycerides in the interface liquid-solid. The whole process is limited by this step since methanol readily adsorbs onto the catalytic surface.

scholarly journals Photoreduction of Cr(VI) Ions in Aqueous Solutions by UV/ Photocatalytic Processes

2012 ◽  
Vol 2012 ◽  
pp. 1-7 ◽  
Author(s):  
Chih Ming Ma ◽  
Yung Shuen Shen ◽  
Po Hsiang Lin
Keyword(s):  
Aqueous Solutions ◽  
Reaction Rate ◽  
Removal Rate ◽  
Experimental Results ◽  
Order Kinetic ◽  
Solution Ph ◽  
Relationship Of ◽  
The Relationship ◽  
Photocatalytic Processes ◽  
Order Kinetic Equation

This study discussed the photoreduction of Cr(VI) ions in aqueous solutions by UV/TiO2photocatalytic processes under various operational factors. Experimental results showed that the removal rate of Cr(VI) increased with decreasing solution pH values and with increasing dosages of organic compounds, indicating that the recombination rate of electrons and h+can be retarded in the reaction systems by the addition of the scavenger, thus raising the reaction rate of Cr(VI). The relationship of the chemical reaction rate of Cr(VI), TiO2dosage, and changes of Cr(VI) concentration was expressed by the pseudo-first-order kinetic equation. Comparing the experimental results of two different doping metals in modified TiO2photoreduction systems, the removal rate of Cr(VI) by the Ag/TiO2process is larger, possibly because the electron transferring ability of Ag is superior to that of Cu. However, the photoreduction rates of Cr(VI) by modified UV/TiO2processes are worse than those by a nonmodified commercial UV/TiO2process.

scholarly journals Kinetic Modeling of a Heterogeneous Fenton Oxidative Treatment of Petroleum Refining Wastewater

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Diya'uddeen Basheer Hasan ◽  
Abdul Aziz Abdul Raman ◽  
Wan Mohd Ashri Wan Daud
Keyword(s):  
Kinetic Model ◽  
Direct Conversion ◽  
Order Kinetic ◽  
Initial Oxidation ◽  
Oxidation Step ◽  
Kinetic Rate Constants ◽  
Order Kinetic Model ◽  
Generalized Kinetic Model ◽  
Petroleum Refinery Effluent ◽  
Kinetics Of

The mineralisation kinetics of petroleum refinery effluent (PRE) by Fenton oxidation were evaluated. Within the ambit of the experimental data generated, first-order kinetic model (FKM), generalised lumped kinetic model (GLKM), and generalized kinetic model (GKM) were tested. The obtained apparent kinetic rate constants for the initial oxidation step (k2′), their final oxidation step (k1′), and the direct conversion to endproducts step (k3′) were 10.12, 3.78, and 0.24 min−1for GKM; 0.98, 0.98, and nil min−1for GLKM; and nil, nil, and >0.005 min−1for FKM. The findings showed that GKM is superior in estimating the mineralization kinetics.

scholarly journals Kinetic Analysis for Agglomeration-Flotation of Finely Ground Chalcopyrite: Comparison of First Order Kinetic Model and Experimental Results

2020 ◽  
Vol 61 (10) ◽  
pp. 1940-1948
Author(s):  
Vothy Hornn ◽  
Mayumi Ito ◽  
Ryosuke Yamazawa ◽  
Hiromasa Shimada ◽  
Carlito Baltazar Tabelin ◽  
...  
Keyword(s):  
Kinetic Model ◽  
Kinetic Analysis ◽  
Experimental Results ◽  
Order Kinetic ◽  
First Order ◽  
Order Kinetic Model

scholarly journals Kinetic study of the hydration of propylene oxide in the presence of heterogeneous catalyst

2017 ◽  
Vol 23 (4) ◽  
pp. 573-580 ◽  
Author(s):  
Sema Akyalcin
Keyword(s):  
Kinetic Study ◽  
Heterogeneous Catalyst ◽  
Propylene Oxide ◽  
Rate Constants ◽  
Reaction Rate ◽  
Batch Reactor ◽  
Catalyst Loading ◽  
Catalyzed Reactions ◽  
Kinetics Of ◽  
Homogeneous Mechanism

The kinetics of the hydration of propylene oxide was studied using a pressurized batch reactor for both uncatalyzed and heterogeneously catalyzed reactions. Lewatit MonoPlus M500/HCO3 - was used as heterogeneous catalyst, which showed better performance than Dowex Marathon A/HCO3 -. The effects of the parameters, namely internal and external diffusion resistances, temperature, catalyst loading and mole ratios of reactants, on the reaction rate were studied. The uncatalyzed and heterogeneously catalyzed reactions were proven to follow a series-parallel irreversible homogeneous mechanism. The temperature dependencies of the rate constants appearing in the rate expressions were determined.

scholarly journals 1,4-Dioxane Degradation Using Persulfate Ion and Ag(I) Ion

2017 ◽  
Vol 57 (2) ◽  
Author(s):  
Rosa María Felix-Navarro ◽  
Wai Lin Shui ◽  
Arturo Zizumbo-López ◽  
Sergio Pérez-Sicairos ◽  
Edgar Alonso Reynoso-Soto ◽  
...  
Keyword(s):  
Sulfuric Acid ◽  
Aqueous Solutions ◽  
Reaction Rate ◽  
Experimental Results ◽  
Kinetics Of Oxidation ◽  
Decay Model ◽  
Increasing Temperature ◽  
Kinetics Of

The kinetics of oxidation of 1,4-dioxane by persulfate ion with Ag+ in aqueous solutions at various temperatures and concentrations of S<sub>2</sub>O<sub>8</sub><sup>2-</sup>, Ag<sup>+</sup> and H<sub>2</sub>SO<sub>4</sub>, were investigated. Experimental results indicate that 1,4-dioxane degradation follows a pseudo-firstorder decay model and that reaction rate significantly accelerate by increasing temperature and concentration of oxidant, sulfuric acid and Ag<sup>+</sup> ions up to 0.46 mM; for the range from 0.46-0.70 mM of Ag<sup>+</sup> ions the reaction rate remains constant and at higher concentrations the reaction rate decreases. It was possible to degrade approximately 100% of 1,4-dioxane in less than one hour with the following conditions: [Ag<sup>+</sup>] = 0.46 mM, H<sub>2</sub>SO<sub>4</sub>] = 0.30 M and from a concentration of 25 mM Na<sub>2</sub>SO<sub>4</sub>.

A kinetic model of superoxide production from single pulmonary alveolar macrophages

1989 ◽  
Vol 256 (2) ◽  
pp. C405-C412 ◽  
Author(s):  
K. A. DiGregorio ◽  
E. V. Cilento ◽  
R. C. Lantz
Keyword(s):  
Superoxide Dismutase ◽  
Kinetic Model ◽  
Cell Surface ◽  
Nadph Oxidase ◽  
Alveolar Macrophages ◽  
Experimental Results ◽  
Model Predictions ◽  
Pulmonary Alveolar Macrophages ◽  
Positively Charged ◽  
Steric Hindrances

A kinetic model was developed to describe the production of superoxide (O2-) by single pulmonary alveolar macrophages (PAM). Model predictions were compared with experimental results obtained from single rat PAM. The O2- was quantified by measuring the reduction of nitro blue tetrazolium (NBT) to a diformazan precipitate (NBTH2) from video-recorded images of individual cells. The kinetic model considered three reactions: 1) the production of extracellular O2- from the reduction of oxygen by NADPH oxidase using intracellular NADPH as the substrate, 2) the subsequent dismutation of O2- to form H2O2, and 3) the reaction of O2- and NBT to form diformazan. NBT specificity for O2- was analyzed by comparing results in the presence and absence of superoxide dismutase (SOD) that catalyzes the dismutation of O2- to H2O2. Measured PAM heterogeneity was accounted for by varying the concentration of intracellular NADPH, its rate of depletion, and the concentration of intracellular NADPH oxidase in the kinetic model. Model predictions compared favorably with experimental results except when SOD was present. This discrepancy may be due to diffusional limitations because NBT is a relatively small molecule (818 mol wt) compared with SOD (34,000 mol wt). In addition, the cell surface is both ruffled and negatively charged, which may introduce steric hindrances and/or electrostatic effects, since SOD is also negatively charged, whereas NBT is positively charged.

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