Reactions at Solid−Liquid Interfaces. The Mechanism and Kinetics of the Fluorination of 2,4-Dinitrochlorobenzene Using Solid Potassium Fluoride in Dimethylformamide

2001 ◽  
Vol 105 (50) ◽  
pp. 12534-12546 ◽  
Author(s):  
Gavin Macfie ◽  
Benjamin A. Brookes ◽  
Richard G. Compton
Keyword(s):  
Potassium Fluoride ◽  
Liquid Interfaces ◽  
Mechanism And Kinetics ◽  
Solid Liquid ◽  
Kinetics Of

scholarly journals Mechanism and Kinetics of Malachite Dissolution in an NH4OH System

Metals ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 833
Author(s):  
Alvaro Aracena ◽  
Javiera Pino ◽  
Oscar Jerez
Keyword(s):  
Ammonium Hydroxide ◽  
Copper Recovery ◽  
X Ray Diffraction ◽  
Solution Ph ◽  
Acid Dissolution ◽  
Acid Consumption ◽  
Mechanism And Kinetics ◽  
Solid Liquid ◽  
Kinetics Of ◽  
Highly Porous

Copper oxide minerals composed of carbonates consume high quantities of leaching reagent. The present research proposes an alternative procedure for malachite leaching (Cu2CO3(OH)2) through the use of only compound, ammonium hydroxide (NH4OH). Preliminary studies were also carried out for the dissolution of malachite in an acid system. The variables evaluated were solution pH, stirring rate, temperature, NH4OH concentration, particle size, solid/liquid ratio and different ammonium reagents. The experiments were carried out in a stirred batch system with controlled temperatures and stirring rates. For the acid dissolution system, sulfuric acid consumption reached excessive values (986 kg H2SO4/ton of malachite), invalidating the dissolution in these common systems. On the other hand, for the ammoniacal system, there was no acid consumption and the results show that copper recovery was very high, reaching values of 84.1% for a concentration of 0.2 mol/dm3 of NH4OH and an experiment time of 7200 s. The theoretical/thermodynamic calculations indicate that the solution pH was a significant factor in maintaining the copper soluble as Cu(NH3)42+. This was validated by the experimental results and solid analysis by X-ray diffraction (XRD), from which the reaction mechanisms were obtained. A heterogeneous kinetic model was obtained from the diffusion model in a porous layer for particles that begin the reaction as nonporous but which become porous during the reaction as the original solid splits and cracks to form a highly porous structure. The reaction order for the NH4OH concentration was 3.2 and was inversely proportional to the square of the initial radius of the particle. The activation energy was calculated at 36.1 kJ/mol in the temperature range of 278 to 313 K.

Elovich Equation for the Kinetics of Isotopic Exchange Reactions at Solid–Liquid Interfaces

Nature ◽  
1970 ◽  
Vol 226 (5241) ◽  
pp. 148-149 ◽  
Author(s):  
R. J. ATKINSON ◽  
F. J. HINGSTON ◽  
A. M. POSNER ◽  
J. P. QUIRK
Keyword(s):  
Isotopic Exchange ◽  
Liquid Interfaces ◽  
Exchange Reactions ◽  
Elovich Equation ◽  
Solid Liquid ◽  
Kinetics Of

scholarly journals Strange kinetics of bulk-mediated diffusion on lipid bilayers

2016 ◽  
Vol 18 (18) ◽  
pp. 12633-12641 ◽  
Author(s):  
Diego Krapf ◽  
Grace Campagnola ◽  
Kanti Nepal ◽  
Olve B. Peersen
Keyword(s):  
Lipid Bilayers ◽  
Anomalous Diffusion ◽  
Observation Time ◽  
Liquid Interfaces ◽  
Large Fluctuations ◽  
Biophysical Processes ◽  
P Diffusion ◽  
Time Averages ◽  
Solid Liquid ◽  
Kinetics Of

Diffusion at solid–liquid interfaces, which is crucial in many technological and biophysical processes, shows large fluctuations in time averages, dependence on observation time, and strong anomalous diffusion.

scholarly journals Mass Transfer in the Solid-Liquid System: Mechanism and Kinetics of the Extraction Process

2020 ◽  
Vol 14 (1) ◽  
pp. 121-128
Author(s):  
Yevgen Semenyshyn ◽  
◽  
Volodymyr Atamanyuk ◽  
Tetiana Rymar ◽  
Oleksandr Ivashchuk ◽  
...  
Keyword(s):  
Mass Transfer ◽  
Extraction Process ◽  
Liquid System ◽  
Mechanism And Kinetics ◽  
Solid Liquid ◽  
Kinetics Of ◽  
System Mechanism
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