Kinetics of a Moving Boundary Ion-Exchange Process

1974 ◽  
Vol 13 (1) ◽  
pp. 20-26 ◽  
Author(s):  
Paul R. Dana ◽  
Thomas D. Wheelock
Keyword(s):  
Ion Exchange ◽  
Moving Boundary ◽  
Exchange Process ◽  
Ion Exchange Process ◽  
Kinetics Of

Kinetics of ion exchange process for separation of glutamic acid

1989 ◽  
Vol 4 (6) ◽  
pp. 249-256 ◽  
Author(s):  
T. H. �zdamar ◽  
S. Taka� ◽  
G. �alik ◽  
R. Ballica
Keyword(s):  
Ion Exchange ◽  
Glutamic Acid ◽  
Exchange Process ◽  
Ion Exchange Process ◽  
Kinetics Of ◽  
Kinetics Of Ion Exchange

Zur Kinetik der Ionenaustauscher III. Die Filmdiffusion bei vollständigen Umbeladungen

1969 ◽  
Vol 24 (6) ◽  
pp. 900-902
Author(s):  
Kurt Bunzel
Keyword(s):  
Ion Exchange ◽  
Exchange Reaction ◽  
Exchange Process ◽  
Ionic Composition ◽  
Selectivity Coefficient ◽  
Film Diffusion ◽  
Ion Exchange Process ◽  
Ion Exchange Reaction ◽  
Diffusion Controlled ◽  
Kinetics Of

The selectivity coefficient K21 of an ion-exchange process is in general a function of the ionic composition of the material. As a result, the value of K21 will change continuously during a com­plete conversion of the ion-exchanger. Equations for the kinetics of such a conversion with variable K21 are given for a film diffusion controlled ion-exchange reaction.

Synthesis of linear alkylbenzene sulphonate intercalated iron(II) iron(III) hydroxide sulphate (green rust) and adsorption of carbon tetrachloride

Clay Minerals ◽  
2007 ◽  
Vol 42 (3) ◽  
pp. 307-317 ◽  
Author(s):  
K. B. Ayala-Luis ◽  
D. K. Kaldor ◽  
C. Bender Koch ◽  
B. W. Strobel ◽  
H. C. B. Hansen
Keyword(s):  
Carbon Tetrachloride ◽  
Ion Exchange ◽  
Exchange Process ◽  
Green Rust ◽  
Stoichiometric Ratio ◽  
X Ray Diffraction ◽  
Linear Alkylbenzene ◽  
Ion Exchange Process ◽  
Linear Alkylbenzene Sulphonate ◽  
Kinetics Of

AbstractGreen rusts, GRs, can act as both sorbents and reductants towards selected pollutants. Organo-GRs are expected to combine these properties with a high affinity for hydrophobic substances. A novel organo-GR, GRLAS, was synthesized by incorporating a mixture of linear alkylbenzenesulphonates (LAS) into the interlayer space of synthetic sulphate green rust, GRSO4 . Mössbauer analysis of GRLAS indicates that the structure of the organo-GR is very similar to that of the initial GRSO4 with regard to the FeII/FeIII ratio and local coordination of Fe atoms. X-ray diffraction demonstrates that the GRLAS formed was well ordered, although a mixture of surfactant was used for intercalation. The basal spacings of the GRLAS and the kinetics of the ion-exchange process were dependent on the initial surfactant loading; basal spacings of ~2.85 nm were obtained at LAS solution concentrations >10 mM. The ratio LASadsorbed/SO42–desorbed significantly exceeded the stoichiometric ratio of 2 during the initial part of the ion-exchange process (t = 5 h). However, this ratio was reached progressively with time. GRSO4 preferentially sorbed LAS homologues with long alkyl chains over short ones. Carbon tetrachloride was successfully adsorbed into GRLAS. The adsorption isotherm was linear with a distribution coefficient, Kd, of 505±19 litre kg–1.

scholarly journals History, Introduction, and Kinetics of Ion Exchange Materials

2013 ◽  
Vol 2013 ◽  
pp. 1-13 ◽  
Author(s):  
Sanjeev Kumar ◽  
Sapna Jain
Keyword(s):  
Ion Exchange ◽  
Exchange Process ◽  
Paper Briefly ◽  
Factors Affecting ◽  
Controlled Diffusion ◽  
Ion Exchange Process ◽  
History Of ◽  
Laboratory Tool ◽  
Kinetics Of ◽  
Kinetics Of Ion Exchange

During the last few decades, ion exchange materials have evolved from laboratory tool to industrial products with significant technical and commercial impact. The current paper briefly summarizes the history of the development of the ion exchange materials. The paper defines the ion exchange materials and their types. The paper signifies the kinetics involved in the ion exchange process with description of factors affecting the rate of ion exchange. The mechanism of ion exchange has also been delineated through schematic diagram, illustrating that there are two types of diffusion, film and particle controlled diffusion. A brief of mathematical approach for kinetics of ion exchange has also been incorporated.

Determination of the ion exchange process of K2Ti4O9 fibers at constant pH and modeling with statistical rate theory

RSC Advances ◽  
2015 ◽  
Vol 5 (90) ◽  
pp. 73474-73480 ◽  
Author(s):  
Chang Liu ◽  
Nanhua Wu ◽  
Jun Wang ◽  
Liangliang Huang ◽  
Xiaohua Lu
Keyword(s):  
Ion Exchange ◽  
Exchange Process ◽  
Rate Theory ◽  
Ion Exchange Process ◽  
Statistical Rate Theory ◽  
Constant Ph ◽  
Ion Exchange Kinetics ◽  
Exchange Kinetics ◽  
Kinetics Of

The ion exchange kinetics of K2Ti4O9 fibers at constant pH was determined precisely by ion-selective electrodes, and activity coefficients of ions in solutions were calculated by the Lu–Maurer equation.

Separation kinetics of l-phenylalanine by ion-exchange process

1998 ◽  
Vol 2 (2) ◽  
pp. 101-112 ◽  
Author(s):  
Serpil Takaç ◽  
Güzide Çalık ◽  
Meryem Aytar ◽  
Tunçer H. Özdamar
Keyword(s):  
Ion Exchange ◽  
Exchange Process ◽  
Ion Exchange Process ◽  
Kinetics Of ◽  
Separation Kinetics

Removal of Toxic Dyestuffs from Aqueous Solution by Amphoteric Bioadsorbent

2020 ◽  
Vol 16 ◽  
Author(s):  
Reda M. El-Shishtawy ◽  
Abdullah M. Asiri ◽  
Nahed S. E. Ahmed
Keyword(s):  
Aqueous Solution ◽  
Ion Exchange ◽  
Dye Removal ◽  
Exchange Process ◽  
Cationic Dyes ◽  
Carboxyl Groups ◽  
Maximum Adsorption Capacity ◽  
Equilibrium Isotherm ◽  
Ion Exchange Process ◽  
Dyes And Pigments

Background: Color effluents generated from the production industry of dyes and pigments and their use in different applications such as textile, paper, leather tanning, and food industries, are high in color and contaminants that damage the aquatic life. It is estimated that about 105 of various commercial dyes and pigments amounted to 7×105 tons are produced annually worldwide. Ultimately, about 10–15% is wasted into the effluents of the textile industry. Chitin is abundant in nature, and it is a linear biopolymer containing acetamido and hydroxyl groups amenable to render it atmospheric by introducing amino and carboxyl groups, hence able to remove different classes of toxic organic dyes from colored effluents. Methods: Chitin was chemically modified to render it amphoteric via the introduction of carboxyl and amino groups. The amphoteric chitin has been fully characterized by FTIR, TGA-DTG, elemental analysis, SEM, and point of zero charge. Adsorption optimization for both anionic and cationic dyes was made by batch adsorption method, and the conditions obtained were used for studying the kinetics and thermodynamics of adsorption. Results: The results of dye removal proved that the adsorbent was proven effective in removing both anionic and cationic dyes (Acid Red 1 and methylene blue (MB)), at their respective optimum pHs (2 for acid and 8 for cationic dye). The equilibrium isotherm at room temperature fitted the Freundlich model for MB, and the maximum adsorption capacity was 98.2 mg/g using 50 mg/l of MB, whereas the equilibrium isotherm fitted the Freundlich and Langmuir model for AR1 and the maximum adsorption capacity was 128.2 mg/g. Kinetic results indicate that the adsorption is a two-step diffusion process for both dyes as indicated by the values of the initial adsorption factor (Ri) and follows the pseudo-second-order kinetics. Also, thermodynamic calculations suggest that the adsorption of AR1 on the amphoteric chitin is an endothermic process from 294 to 303 K. The result indicated that the mechanism of adsorption is chemisorption via an ion-exchange process. Also, recycling of the adsorbent was easy, and its reuse for dye removal was effective. Conclusion: New amphoteric chitin has been successfully synthesized and characterized. This resin material, which contains amino and carboxyl groups, is novel as such chemical modification of chitin hasn’t been reported. The amphoteric chitin has proven effective in decolorizing aqueous solution from anionic and cationic dyes. The adsorption behavior of amphoteric chitin is believed to follow chemical adsorption with an ion-exchange process. The recycling process for few cycles indicated that the loaded adsorbent could be regenerated by simple treatment and retested for removing anionic and cationic dyes without any loss in the adsorbability. Therefore, the study introduces a new and easy approach for the development of amphoteric adsorbent for application in the removal of different dyes from aqueous solutions.

scholarly journals Polyelectrolyte Gels: A Unique Class of Soft Materials

Gels ◽  
2021 ◽  
Vol 7 (3) ◽  
pp. 102
Author(s):  
Ferenc Horkay
Keyword(s):  
Exchange Process ◽  
Interaction Strength ◽  
Soft Materials ◽  
Industrial Applications ◽  
Future Research ◽  
Swelling Kinetics ◽  
Polyelectrolyte Gels ◽  
Ion Exchange Process ◽  
Counter Ions ◽  
Kinetics Of

The objective of this article is to introduce the readers to the field of polyelectrolyte gels. These materials are common in living systems and have great importance in many biomedical and industrial applications. In the first part of this paper, we briefly review some characteristic properties of polymer gels with an emphasis on the unique features of this type of soft material. Unsolved problems and possible future research directions are highlighted. In the second part, we focus on the typical behavior of polyelectrolyte gels. Many biological materials (e.g., tissues) are charged (mainly anionic) polyelectrolyte gels. Examples are shown to illustrate the effect of counter-ions on the osmotic swelling behavior and the kinetics of the swelling of model polyelectrolyte gels. These systems exhibit a volume transition as the concentration of higher valence counter-ions is gradually increased in the equilibrium bath. A hierarchy is established in the interaction strength between the cations and charged polymer molecules according to the chemical group to which the ions belong. The swelling kinetics of sodium polyacrylate hydrogels is investigated in NaCl solutions and in solutions containing both NaCl and CaCl2. In the presence of higher valence counter-ions, the swelling/shrinking behavior of these gels is governed by the diffusion of free ions in the swollen network, the ion exchange process and the coexistence of swollen and collapsed states.

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