The Prediction of the Dissolution Rate Constant by Mixing Rules: The Study of Acetaminophen Batches

2008 ◽  
Vol 34 (5) ◽  
pp. 522-535 ◽  
Author(s):  
Tu Lee ◽  
Hung Ju Hou ◽  
Hsiang Yu Hsieh ◽  
Yan Chan Su ◽  
Yeh Wen Wang ◽  
...  
Keyword(s):  
Dissolution Rate ◽  
Rate Constant ◽  
Mixing Rules ◽  
Dissolution Rate Constant

Theory of Copper-Electrolyte Slimes Decoppering in the Presence of Hydrogen Peroxide

2019 ◽  
Vol 946 ◽  
pp. 585-590
Author(s):  
V.G. Lobanov ◽  
K.D. Naumov ◽  
A.A. Korolev
Keyword(s):  
Hydrogen Peroxide ◽  
Dissolution Rate ◽  
Rate Constant ◽  
Chemical Transformations ◽  
Composition Effect ◽  
Rotating Disc ◽  
Copper Dissolution ◽  
Copper Leaching ◽  
Copper Electrolyte ◽  
Dissolution Rate Constant

The problem of copper leaching from copper-electrolyte slimes is discussed. To intensify the long and costly process, it is proposed to use a leaching system containing sulfuric acid and hydrogen peroxide as an oxidizing agent. The chemical transformations possible variants at the treatment of slime under the specified conditions and the thermodynamic parameters of the predicted reactions are considered. Solution composition effect on the copper dissolution rate at room temperature was studied in the presence of hydrogen peroxide using the rotating disc technique. It is found that dissolution rate constant at using hydrogen peroxide slightly inferior to dissolution rate constant under autoclaved conditions in an oxygen atmosphere.

Mechanisms and Kinetics of Silica-Rich Binary Na2O-SiO2 Glass Corrosion in 100°C Water at pH=7

2007 ◽  
Vol 336-338 ◽  
pp. 1823-1826 ◽  
Author(s):  
K.G. Nickel ◽  
S. Merkel
Keyword(s):  
Dissolution Rate ◽  
Rate Constant ◽  
Edge Length ◽  
Sio2 Content ◽  
Shrinking Core Model ◽  
Water Interaction ◽  
Glass Corrosion ◽  
Shrinking Core ◽  
Dissolution Rate Constant ◽  
Kinetics Of

Sodium-rich glasses of the system Na2O-SiO2 are well known to be easily soluble in water. This is not true for silica-rich compositions. We have manufactured quenched glasses with silica contents between 65 and 80 wt.% SiO2 and followed the water interaction at 100°C by measuring mass and sample dimensions in intervals. Comparing the path of edge length, mass and volume to a general shrinking core model for cuboids we conclude that only compositions between 65 and 70 wt% SiO2 can be described well by a simple dissolution process. The logarithm of the dissolution rate constant varies linearly with the SiO2 content. At higher silica contents the mechanism changes towards leaching of sodium. We propose changing glass structures to be responsible for the change in mechanism.

Ultrasonic-Assisted Dissolution of Polystyrene in Decahydronaphthalene for the Preparation of Poly(Cyclohexylethylene)

2014 ◽  
Vol 651-653 ◽  
pp. 157-160
Author(s):  
Jia Jia Wang ◽  
Hui Huang ◽  
Ting Li ◽  
Shi Ying Tao
Keyword(s):  
Kinetic Model ◽  
Dissolution Rate ◽  
Rate Constant ◽  
Dissolution Kinetic ◽  
Dissolution Process ◽  
Dissolution Time ◽  
Mechanical Agitation ◽  
Ultrasonic Assisted ◽  
Dissolution Rate Constant ◽  
Dissolution Ratio

Dissolution process of polystyrene in decahydronaphthalene solution was conducted and compared under different conditions. The effects of dissolution time and temperature on the dissolution ratio of polystyrene were performed with the assistance of ultrasonic and mechanical agitation, respectively. The dissolution ratio of polystyrene increased with the increment of dissolution time and dissolution temperature, polystyrene dissolved faster under ultrasonic-assisted process. The polystyrene dissolution kinetic model was developed and used to calculate the dissolution rate constant. The kinetic model showed good agreement with the experimental data, and the dissolution rate constant indicated that ultrasonic can obviously enhance the dissolution process of polystyrene in decahydronaphthalene solution.

Effect of Fly Ash as an Additive on the Limestone Dissolution Rate Constant

2015 ◽  
Vol 29 (5) ◽  
pp. 3284-3291 ◽  
Author(s):  
Lawrence Koech ◽  
Hilary Rutto ◽  
Hein Neomagus ◽  
Ray Everson ◽  
Letsabisa Lerotholi
Keyword(s):  
Fly Ash ◽  
Dissolution Rate ◽  
Rate Constant ◽  
Limestone Dissolution ◽  
Dissolution Rate Constant

scholarly journals Dissolution measurement free from mass transport

2012 ◽  
Vol 85 (1) ◽  
pp. 61-70 ◽  
Author(s):  
Jean Colombani
Keyword(s):  
Mass Transport ◽  
Dissolution Rate ◽  
Rate Constant ◽  
Surface Reaction ◽  
Dissolution Kinetics ◽  
Dissolution Rates ◽  
Apparent Inconsistency ◽  
Dissolution Rate Constant

Standard dissolution experiments are carried out in stirred liquid. Therefore, the measured dissolution rate contains also diffusive and convective contributions, besides the desired surface reaction contribution. We present here a methodology, based on the hydrodynamical analysis of classical dissolution experiments, enabling us to extract the pure dissolution rate constant from the set of the already measured dissolution rates. The application of this analysis to the case of gypsum shows that the removal of the mass transport contribution from the dissolution rates of this mineral found in the literature brings, despite their apparent inconsistency, a coherent description of its dissolution kinetics and a well-defined value of its rate constant.

Calcium carbonate preservation in the ocean

1990 ◽  
Vol 331 (1616) ◽  
pp. 29-40 ◽  
Keyword(s):  
Organic Matter ◽  
Calcium Carbonate ◽  
Dissolution Rate ◽  
Rate Constant ◽  
Dissolution Kinetics ◽  
Sediment Surface ◽  
Organic Matter Degradation ◽  
Equatorial Atlantic ◽  
Calcite Saturation ◽  
Dissolution Rate Constant

Recent microelectrode pH and O 2 measurements across the sediment-water interface suggest CaCO 3 dissolution kinetics substantially slower than laboratory values and support a dissolution response to organic matter degradation near the sediment surface. We report a modelling exercise, motivated by these results, that indicates the pattern of calcium carbonate preservation in the equatorial Atlantic and Indian oceans is most readily reproduced using a dissolution rate constant 10 to 100 times smaller than those measured in the laboratory. The model suggests that 40% or more of the particulate CaCO 3 rain dissolves at the calcite saturation horizon in response to organic matter degradation within the sediments, and that this effect is insensitive to the choice of dissolution rate constant in ranges measured. Implications are that the dissolution flux from the sediments is greater than previously thought, and that calcium carbonate preservation in the deep sea should be strongly dependent on the particulate organic carbon to calcium carbonate rain ratio.

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