scholarly journals Optimization and Kinetics of Zirconium Oxychloride (ZOC) Dissolution Using HNO3

2019 ◽  
Vol 19 (4) ◽  
pp. 928
Author(s):  
Maria Veronika Purwani ◽  
Muzakky Muzakky
Keyword(s):  
Reaction Mechanism ◽  
Dissolution Kinetics ◽  
Frequency Factor ◽  
Chemical Reactor ◽  
Extraction Process ◽  
Zirconium Oxychloride ◽  
Reaction Rate Constant ◽  
K Value ◽  
Hno3 Concentration ◽  
Kinetics Of

The design of chemical reactor can not be separated from the optimization data and reaction kinetics obtained from the experimental measurement. Through the idea of making the dissolution reactor design, the purpose of this research is to obtain optimization data and dissolution kinetics of Zirconium Oxide Chloride (ZOC) using HNO3. The design of the solvent reactor is required to make the feedstock in the liquid-liquid extraction process continuously. The extraction process is a mini-pilot plant unit as a nuclear-grade zirconia manufacture. The dissolution optimization was carried out by dissolving ZOC solids of zircon sand processed products using HNO3 in a container with some variation of contact time, HNO3 concentration and temperature. While the kinetics data was gained by extracting from the optimization data obtained based on the formula of reaction orders. The investigation result with 6 gr of ZOC and 6M HNO3 concentration obtained the best contact optimum time of 2 minutes and the conversion number (α) of 0.96. The dissolution reaction mechanism was estimated in accordance with the reaction of order 1 with the  k value of 1.5879 minutes-1. It was predicted that the reaction mechanism of ZOC dissolution in HNO3 begins with diffuse control and is followed by chemical reaction control. With increasing conversion temperature, the conversion will increase to 0.98, while the reaction also follows the reaction order 1. The optimum temperature at 60 °C, and the correlation between temperature (T) with the calculated reaction rate constant (k) according to the Arrhenius formula yielded an equation of ln k = - 4191,6 / T + 13,903 or k = 13,903.e- 4191,6 / T, with the frequency factor A = 1091430 and the activation energy E = 34,848 kJ / mole.

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.

Acid dissolution of synthetic aluminous goethite before and after transformation to hematite by heating

Clay Minerals ◽  
1995 ◽  
Vol 30 (1) ◽  
pp. 55-65 ◽  
Author(s):  
H. D. Ruan ◽  
R. J. Gilkes
Keyword(s):  
Surface Area ◽  
Heating Temperature ◽  
Dissolution Kinetics ◽  
Frequency Factor ◽  
Dissolution Time ◽  
Unit Surface Area ◽  
Acid Dissolution ◽  
Al Substitution ◽  
Before And After ◽  
Kinetics Of

AbstractMeasurements of the kinetics of acid dissolution of synthetic aluminous goethites and corresponding hematites produced by heating of parent Al-goethites at various temperatures were carried out in 1 M HC1 at 30, 40 and 50°C. Dissolution-time curves show sigmoidal shapes for the goethites (110°C), whereas deceleratory shapes were obtained for most of the partly and fully dehydroxylated samples. The dissolution rate for all materials decreased with increasing Al substitution and increased with increasing dissolution temperature, specific surface area and heating temperature. On a unit surface area basis, hematite dissolved ∼ 2–8 times faster than goethite. Dissolution kinetics of most heated goethite samples (200–260°C) were quite well described (R2 > 0.96) by the modified first-order Kabai equation. The activation energy and frequency factor for dissolution increased with increasing Al substitution.

Dissolution Kinetics of Spinel Lithium Manganate and its Relation to Capacity Fading in Lithium Ion Batteries

2002 ◽  
Vol 17 (6) ◽  
pp. 1476-1481 ◽  
Author(s):  
Chung-Hsin Lu ◽  
Shang-Wei Lin
Keyword(s):  
Elevated Temperatures ◽  
Lithium Ion ◽  
Dissolution Kinetics ◽  
Reaction Rate Constant ◽  
Dissolution Behavior ◽  
Capacity Fading ◽  
Dissolution Reaction ◽  
Lithium Manganate ◽  
Spinel Lithium Manganate ◽  
Kinetics Of

The dissolution behavior and kinetics of spinel lithium manganate LiMn2O4 with different particle sizes have been investigated in this study. The dissolution of manganese cations from LiMn2O4 is confirmed to occur when LiMn2O4 particles are immersed in the electrolytes. The amount of dissolved manganese ions markedly increases with a rise in temperature and a decrease in particle size, which implies that the capacity fading of LiMn2O4 at elevated temperatures is associated with manganese dissolution. On the basis of the isothermal analysis of reaction kinetics, the rate of manganese dissolution from LiMn2O4 is dominated by the rate of dissolution reaction. Smaller particles exhibit a larger reaction rate constant and higher activation energy of the dissolution process than the larger ones. Therefore, an increase in temperature has a more pronounced effect on the dissolution reaction of small particles than on that of large particles.

scholarly journals Kinetics of Colour Development during Frying of Potato Pre-Treated with Pulsed Electric Fields and Blanching: Effect of Cultivar

Foods ◽  
2021 ◽  
Vol 10 (10) ◽  
pp. 2307
Author(s):  
Setya Budi Muhammad Abduh ◽  
Sze Ying Leong ◽  
Chun Zhao ◽  
Samantha Baldwin ◽  
David J. Burritt ◽  
...  
Keyword(s):  
Electric Fields ◽  
Pulsed Electric Fields ◽  
Reaction Rate Constant ◽  
Russet Burbank ◽  
Potato Cultivars ◽  
K Value ◽  
Pre Treatment ◽  
Colour Development ◽  
Different Content ◽  
Kinetics Of

The current research aimed to investigate the effect of pulsed electric fields (1 kV/cm; 50 and 150 kJ/kg) followed by blanching (3 min., 100 °C) on the colour development of potato slices during frying on a kinetic basis. Four potato cultivars ‘Crop77’, ‘Moonlight’, ‘Nadine’, and ‘Russet Burbank’ with different content of glucose and amino acids were used. Lightness (L* values from colorimeter measurement) was used as a parameter to assess the colour development during frying. The implementation of PEF and blanching as sequential pre-treatment prior to frying for all potato cultivars was found effective in improving their lightness in the fried products. PEF pre-treatment did not change the kinetics of L* reduction during frying (between 150 and 190 °C) which followed first-order reaction kinetics. The estimated reaction rate constant (k) and activation energy (Ea based on Arrhenius equation) for non-PEF and PEF-treated samples were cultivar dependent. The estimated Ea values during the frying of PEF-treated ‘Russet Burbank’ and ‘Crop77’ were significantly (p < 0.05) lower (up to 30%) than their non-PEF counterparts, indicating that the change in k value of L* became less temperature dependence during frying. This kinetic study is valuable to aid the optimisation of frying condition in deep-fried potato industries when PEF technology is implemented.

Study on of Cure Reaction Kinetics of Polyamide-Imide-Epoxy Resin

2013 ◽  
Vol 746 ◽  
pp. 128-131 ◽  
Author(s):  
Hai Yang Shi ◽  
Lei Zhang ◽  
Jin Hai Cui
Keyword(s):  
Epoxy Resin ◽  
Reaction Rate ◽  
Curing Kinetics ◽  
Frequency Factor ◽  
Reaction Rate Constant ◽  
The Novel ◽  
Heating Rates ◽  
Cure Reaction ◽  
Kinetics Of ◽  
Dsc Curves

The novel polyamide-imide-epoxy resin was prepared by modification of epoxy resin with polyamide-imide. The DSC curves of the polyamide-imide-epoxy resin were obtained with different heating rates. Moreover, the curing kinetics were also studied by using Kissinger equation, Ozawa and Crane formula, the activation energy of 55.24kJ/mol was acquired, reaction order was 0.9, the frequency factor A and the reaction rate constant Kp at the peak temperature of the reaction was also obtained.

Kinetic Analysis of Alkaline Extraction on Sweet-Bamboo Leaves

2011 ◽  
Vol 332-334 ◽  
pp. 467-470
Author(s):  
Porntip Sae Be ◽  
Suesat Jantip ◽  
Sirisin Chum Rum
Keyword(s):  
Activation Energy ◽  
Kinetic Analysis ◽  
Rate Constant ◽  
Reaction Rate ◽  
Reaction Rate Constant ◽  
Extraction Temperature ◽  
Alkaline Extraction ◽  
K Value ◽  
Bamboo Leaves ◽  
Kinetics Of

This study aimed to investigate the influence of NaOH concentration and temperature used for cellulose extraction from sweet-bamboo leaves on the kinetics of the extraction reaction. The NaOH concentration and the temperature used for the extraction were varied and their effect was examined. It was found that the extraction rate was accelerated by either the increase of NaOH concentration or extraction temperature. The NaOH concentration affected the reaction rate constant, k, and the activation energy, E and the order of the reaction, n. Increase of NaOH concentration enhanced the reaction to move forwards, thus reducing the k and E values of the reaction and the order of the reaction, n, was changed. The correlation of the temperature and the NaOH concentration with the k value showed that at the lower NaOH concentration, the temperature influenced on the k value more significantly. The influence of the NaOH concentration on the k value was lessened with increase of the extraction temperature.

STUDYING THE KINETIC CHARACTERISTICS OF THE EXTRACTION OF ANTHOCYANINS FROM THE SQUEEZE OF KRASNOSTOP ZOLOTOVSKY

2020 ◽  
Author(s):  
M.A. Egyan ◽  
Keyword(s):  
Reaction Rate ◽  
Sugar Content ◽  
Extraction Process ◽  
Efficiency Coefficient ◽  
Kinetic Characteristics ◽  
Reaction Rate Constants ◽  
Solids Content ◽  
Kinetics Of ◽  
Process Speed

The article shows studies characterizing the quality of the squeeze: the mechanical composition of the squeeze is determined, the structural moisture of each component is determined, the sugar content in the formed process of sedimentation of the juice and its acidity are determined refractometrically. The kinetics of anthocyanins extraction was determined in two ways, the solids content in the extract was calculated, and the reaction rate constants of the extraction process and the efficiency coefficient of ultrasonic amplification of the extraction process speed were calculated.

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