Redox Properties of Structural Fe in Smectite Clay Minerals

2011 ◽  
pp. 361-379 ◽  
Author(s):  
Anke Neumann ◽  
Michael Sander ◽  
Thomas B. Hofstetter
Keyword(s):  
Clay Minerals ◽  
Redox Properties ◽  
Smectite Clay

Some Comments on the Chemistry and Stability of Interstratified Illite-Smectite and the Role of Ostwald-Type Processes

Clay Minerals ◽  
1994 ◽  
Vol 29 (1) ◽  
pp. 63-68 ◽  
Author(s):  
T. J. Primmer
Keyword(s):  
Clay Minerals ◽  
Thermodynamic Data ◽  
Ostwald Ripening ◽  
Particle Theory ◽  
Fundamental Particle ◽  
Smectite Clay ◽  
The Relationship ◽  
Particle Thickness

AbstractMuch emphasis has been placed recently on the role of Ostwald-type processes (both ripening and the step rule) in the formation of interstratified illite-smectite clay minerals during diagenesis. Closer investigation of the relationships between illite particle thickness (as defined in terms of the fundamental particle theory) and particle chemistry show that simple Ostwald ripening is too simplistic a mechanism to describe observed changes in illite thickness and composition. In addition, available thermodynamic data on clay minerals suggest that the conventional notion of metastability associated with Ostwald's step rule is an inaccurate description of the relationship between illitic clay minerals and their macroscopic 2 : 1 phyllosilicate analogues.

Assessing the redox properties of iron-bearing clay minerals using homogeneous electrocatalysis

2011 ◽  
Vol 26 ◽  
pp. S191-S193 ◽  
Author(s):  
Christopher A. Gorski ◽  
Michael Sander ◽  
Michael Aeschbacher ◽  
Thomas B. Hofstetter
Keyword(s):  
Clay Minerals ◽  
Redox Properties ◽  
Iron Bearing ◽  
Homogeneous Electrocatalysis

scholarly journals Metal Oxide and Metal Complex Immobilization Modified Smectite Clay For Green Catalysis and Photo-Catalysis Applications: A Mini Review

2018 ◽  
Vol 3 (1) ◽  
pp. 54-59
Author(s):  
Is Fatimah
Keyword(s):  
Catalytic Activity ◽  
Metal Oxide ◽  
Clay Minerals ◽  
Hydrogen Transfer ◽  
Physicochemical Characteristic ◽  
Characteristic Change ◽  
Smectite Clay ◽  
Factors Affecting ◽  
Photo Catalytic Activity ◽  
Green Catalysis

Clay minerals are promising modifiable material for catalysis application. Fit to green chemistry issue, green catalysis based on clay minerals modification has been designed in our research group. Metal oxide and metal complexes modification onto natural and synthetic smectite clay via pillarization and intercalation processes and its application as green catalyst have been investigated.  This paper presents the study on preparation of Ni, Zr and Pt  insertion on smectite clay structure for green conversion of citronellal to menthol via catalytic hydrogen transfer mechanism and Ru-complex modified smectite clay as novel photocatalysis application.  Effect of clay structure modification was also studied in order to investigate the  relationship between physicochemical characteristic change of material modifications and its catalytic/photo-catalytic activity. Some interesting phenomena related to the interaction of metal-clay support for their performance toward reaction kinetics and mechanism are reviewed, with emphasis on the evolution of surface properties and some factors affecting catalytic/photo-catalytic activity

The impact of structural Fe(III) reduction by bacteria on the surface chemistry of smectite clay minerals

1999 ◽  
Vol 63 (22) ◽  
pp. 3705-3713 ◽  
Author(s):  
Joel E. Kostka ◽  
Jun Wu ◽  
Kenneth H. Nealson ◽  
Joseph W. Stucki
Keyword(s):  
Surface Chemistry ◽  
Clay Minerals ◽  
Smectite Clay ◽  
The Impact

Smectite clay minerals: properties and uses

1984 ◽  
Vol 311 (1517) ◽  
pp. 391-409 ◽  
Keyword(s):  
Chemical Composition ◽  
Clay Minerals ◽  
Water Movement ◽  
Consumer Products ◽  
Active Surface Area ◽  
Smectite Clay ◽  
Smectite Clays ◽  
Octahedral Cation ◽  
Fuller’S Earth ◽  
Cation Sites

The physicochemical properties of smectite clay minerals that determine their industrial utilization are reviewed. Smectite is the name used for a group of phyllosilicate mineral species, the most important of which are montmorillonite, beidellite, nontronite, saponite and hectorite. These and several other less common species are differentiated by variations in chemical composition involving substitutions of Al for Si in tetrahedral cation sites and Al, Fe, Mg and Li in octahedral cation sites. Smectite clays have a variable net negative charge, which is balanced by Na, Ca, Mg and, or, H adsorbed externally on interlamellar surfaces. The structure, chemical composition, exchangeable ion type and small crystal size of smectite clays are responsible for several unique properties, including a large chemically active surface area, a high cation exchange capacity, interlamellar surfaces having unusual hydration characteristics, and sometimes the ability to modify strongly the flow behaviour of liquids. In terms of major industrial and chemical uses, natural smectite clays can be divided into three categories, Na smectites, Ca-Mg smectites and Fuller’s or acid earths. Large volumes of Na smectites and Na-exchanged Ca-M g smectites and Fuller’s earth are directly used in the foundry, oil well drilling, wine, and iron ore and feed pelletizing industries, and are also used in civil engineering to impede water movement. Significant volumes of Na smectites are used for various purposes in the manufacturing of many industrial, chemical and consumer products. Large quantities of Ca-M g smectites are used directly in iron foundries, in agricultural industries and for filtering and decolorizing various types of oils. A significant fraction of the Ca-M g smectites used for decolorizing has been acid treated. Large volumes of Fuller’s or acid earths are commercially used for preparing animal litter trays and oil and grease absorbents, as carriers for insecticides, and for decolorizing of oils and fats. Natural Na smectites occur in commercial quantities in only a few places, but Ca-M g smectite and Fuller’s earth deposits of considerable size occur on almost every continent.

K-Ar dating of authigenic illite-smectite clay material: application to complex mixtures of mixed-layer assemblages

Clay Minerals ◽  
1991 ◽  
Vol 26 (2) ◽  
pp. 189-198 ◽  
Author(s):  
J.-R. Mossmann
Keyword(s):  
Clay Minerals ◽  
Mixed Layer ◽  
Upper Triassic ◽  
Complex Mixtures ◽  
Clay Material ◽  
Paris Basin ◽  
Smectite Clay ◽  
Isotopic Dating

AbstractGenetically homogeneous clay fractions are not always available for K-Ar isotopic dating of authigenic sedimentary material, particularly when dating illitic mixed-layer clay minerals. Three populations of mixed-layer clay minerals have been recognized in Upper Triassic sandstones from the Paris Basin (France), their occurrences being related to the flow of allochthonous fluids across the stratigraphic sections of the basin during Mesozoic times. A method is described for interpreting the K-Ar mixture ages obtained on carefully selected fractions, resulting in constraints being able to be made on the timing of the movements of these fluids.

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