Adsorption of Heterogeneously Charged Nanoparticles on a Variably Charged Surface by the Extended Surface Complexation Approach:  Charge Regulation, Chemical Heterogeneity, and Surface Complexation

The acid-base properties of the glauconite surface has been studied by potentiometric titration. Using a surface complexation model with a constant exchange capacity, it was shown that positively charged surface centers and exchange centers dominate in the acidic pH region, and negatively charged centers dominate in the neutral and alkaline regions. The corresponding constants of acid-base equilibrium have been calculated. The data obtained were used to study the sorption of cadmium and lead on glauconite.

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The Electrostatic Interaction of an Assemblage of Charges with a Charged Surface: The Charge-Regulation Effect

Langmuir ◽

10.1021/la991520e ◽

2000 ◽

Vol 16 (18) ◽

pp. 7200-7209 ◽

Cited By ~ 5

Author(s):

Heng-Kwong Tsao

Keyword(s):

Electrostatic Interaction ◽

Charged Surface ◽

Charge Regulation ◽

Regulation Effect

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Surface complexation models for heterogeneous and uneven surfaces – the charge regulation concept applied to simple 2D geometries

10.7185/gold2021.6054 ◽

2021 ◽

Author(s):

Frank Heberling ◽

Teba Gil-Díaz ◽

Johannes Luetzenkirchen

Keyword(s):

Surface Complexation ◽

Charge Regulation

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Predicting the electrokinetic properties on an outcrop and reservoir composite carbonate surfaces in modified salinity brines using extended surface complexation models

Fuel ◽

10.1016/j.fuel.2021.122078 ◽

2022 ◽

Vol 309 ◽

pp. 122078

Author(s):

Joel T. Tetteh ◽

Anthony Pham ◽

Edward Peltier ◽

Justin M. Hutchison ◽

Reza Barati Ghahfarokhi

Keyword(s):

Surface Complexation ◽

Electrokinetic Properties ◽

Extended Surface

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Silicon Tetrachloride Synthesis from Rice Hulls: Transmission and Scanning Electron Microscope Study

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100094437 ◽

1972 ◽

Vol 30 ◽

pp. 236-237 ◽

Cited By ~ 1

Author(s):

Richard S. Thomas ◽

Prabir K. Basu ◽

Francis T. Jones

Keyword(s):

Silicon Tetrachloride ◽

Silica Sand ◽

Mineral Matter ◽

Chemical Heterogeneity ◽

Scanning Electron Microscope Study ◽

Rice Hulls ◽

Hull Structure ◽

Lower Temperature ◽

Image Position ◽

Disposal Problem

Silicon tetrachloride, used in industry for the production of highest purity silicon and silica, is customarily manufactured from silica-sand and charcoal.SiCl4 can also be made from rice hulls, which contain up to 20 percent silica and only traces of other mineral matter. Hulls, after carbonization, actually prove superior as a starting material since they react at lower temperature. This use of rice hulls may offer a new, profitable solution for a rice mill byproduct disposal problem.In studies of the reaction kinetics with carbonized hulls, conversion of SiO2 to SiCl4 was found to proceed within a few minutes to a constant, limited yield which depended reproducibly on the ambient temperature of the reactor. See Fig. 1. This suggested that physical or chemical heterogeneity of the silica in the hull structure might be involved.

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The effects of surface absorbed monolayer microdiffraction patterns

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100105461 ◽

1988 ◽

Vol 46 ◽

pp. 680-681

Author(s):

M. Pan ◽

J.M. Cowley

Keyword(s):

Surface Potential ◽

Electron Probe ◽

Potential Distribution ◽

Crystal Surface ◽

Normal Direction ◽

Surface Image ◽

Extended Surface ◽

Gas Molecules ◽

Surface Nature ◽

Electron Microdiffraction

Electron microdiffraction patterns, obtained when a small electron probe with diameter of 10-15 Å is directed to run parallel to and outside a flat crystal surface, are sensitive to the surface nature of the crystals. Dynamical diffraction calculations have shown that most of the experimental observations for a flat (100) face of a MgO crystal, such as the streaking of the central spot in the surface normal direction and (100)-type forbidden reflections etc., could be explained satisfactorily by assuming a modified image potential field outside the crystal surface. However the origin of this extended surface potential remains uncertain. A theoretical analysis by Howie et al suggests that the surface image potential should have a form different from above-mentioned image potential and also be smaller by several orders of magnitude. Nevertheless the surface potential distribution may in practice be modified in various ways, such as by the adsorption of a monolayer of gas molecules.

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