Characterization of salt- and surfactant-containing sandy soil extracts by laser light methods

Abstract The aim of this work was to study how different salt and surfactant solutions influence the particle size distribution and colloidal stability of sandy soil extracts. Particle size distribution was investigated by the laser diffraction method. Extracts were made from the soil – before and after removing its organic content – with solutions of NaCl or CaCl2 and one cationic and two anionic surfactants. The surfactants influence the particle size distribution of the soil. Due to the use of the NaCl and surfactant mixtures after removal of organic content, the particle sizes increased compared to the extract of the soil. Colloidal stability was investigated by the laser Doppler electrophoresis method resulting in a zeta potential between −5.63 and −23.7 mV, showing that the extracts were rather instable. Static equilibrium experiments with sodium dodecyl sulphate on sandy soil resulted in an L-type of isotherm with three steps, indicating the formation of more surface layers. Comparison of the adsorption isotherm and the measurements of particle size distribution demonstrated that the particle size changes comparably with the formation of the different layers. The zeta potential of the equilibrated solution reached the region of instability and stability when the initial concentration of sodium dodecyl sulphate was near its critical micelle concentration.

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Effect of Dispersant on the Measurement of Particle Size Distribution of Titanium Dioxide

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.512-515.261 ◽

2012 ◽

Vol 512-515 ◽

pp. 261-264

Author(s):

Li Shen ◽

Jin Hu ◽

Da Ping Wu

Keyword(s):

Particle Size ◽

Titanium Dioxide ◽

Zeta Potential ◽

Particle Size Distribution ◽

Size Distribution ◽

Anionic Surfactant ◽

Sodium Sulfate ◽

Aqueous Media ◽

Rutile Tio2 ◽

Tio2 Particles

As anionic surfactant, a commercial salt of lauryl sodium sulfate was used. The effects of different amounts of dispersant on the measurement of particle size distribution between two titanium dioxide powders (anatase and rutile) in aqueous media were discussed. Diluted aqueous suspensions were characterized in terms of particle size distribution and zeta potential. The results demonstrate that the measurement of particle size distribution strongly depends on the amounts of dispersant. The amounts of dispersant have a significant effect on the behavior of the rutile-TiO2 particles. The particle size first decreases significantly with an increase in the amounts of dispersant and then lesser increases with a further increase in the amounts of dispersant. The tendency show significant differences between two particles.

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Particle Size Distribution of ZrO2:Pr3+ – Influences of pH, High Power Ultrasound, Surfactant and Dopant Quantity

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.128.97 ◽

2007 ◽

Vol 128 ◽

pp. 97-100 ◽

Cited By ~ 3

Author(s):

Stephanie Möller ◽

Janusz D. Fidelus ◽

Witold Łojkowski

Keyword(s):

Particle Size ◽

Particle Size Distribution ◽

Size Distribution ◽

High Power ◽

Average Particle Size ◽

Sodium Dodecyl ◽

Average Particle ◽

Power Ultrasound ◽

High Power Ultrasound ◽

Influence Of Ph

The aim of the work was to examine the influence of pH, high power ultrasound, surfactant and dopant quantity on the particle size distribution of ZrO2:Pr3+, with praseodymium content varying between 0.05 and 10 %. The nanopowders were obtained via a hydrothermal microwave driven process. To establish if the dopant was located on the surface of the zirconia nanoparticles, the particle size distribution, as a function of pH, was measured to obtain an estimate of the isoelectric point of the samples. All results indicated that the dopant was concentrated on the surface: the measurements of the particle size distribution show that the pH corresponding to maximum average particle size changes towards higher values when the Pr content increases. Measurements of the particle size distribution dependency on the application of high power ultrasound and the addition of the sodium dodecyl sulphate surfactant show that, under certain conditions, there is a better stabilisation of the nanopowders in a dispersion and undesirable agglomeration is hindered.

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Removal of clay and blue-green algae particles through zeta potential and particle size distribution in the dissolved air flotation process

Water Science & Technology Water Supply ◽

10.2166/ws.2006.011 ◽

2006 ◽

Vol 6 (1) ◽

pp. 95-103 ◽

Cited By ~ 5

Author(s):

D.H. Kwak ◽

S.J. Kim ◽

H.J. Jung ◽

C.H. Won ◽

S.B. Kwon ◽

...

Keyword(s):

Particle Size ◽

Zeta Potential ◽

Particle Size Distribution ◽

Size Distribution ◽

Green Algae ◽

Dissolved Air Flotation ◽

Flotation Process ◽

Clay Particles ◽

Blue Green Algae ◽

Dissolved Air

The raw water characteristics of a water treatment plant in Korea are mainly dependent on two major factors: the clay particles attributed to rainfall and blue-green algae in reservoirs. In this work, zeta potential and particle size distributions of clay and algae particles, which are the important parameters affecting their removal efficiency, were measured to investigate the behavior and removal characteristics of particles under various conditions. The results showed that the zeta potential of blue-green algae was more sensitive to treatment conditions than clay, and it fluctuated highly with coagulant dosage, suggesting that the control of zeta potential is important for effective removal of algae particles. On the other hand, the range of particle size distribution that remained from the preliminary sedimentation tank was generally smaller than for flotation. However, the zeta potential of the remaining particles was either close to the isoelectric point or positive, and the particles were not so hard to remove for that reason. In the final analysis, for simultaneous removal of clay and algae particles, a sufficient zeta potential difference must be formed not only for algae particles but also for small clay particles from the sedimentation tank in the dissolved air flotation process.

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Preparation of Chitosan-Silver Nanoparticles in Nonaqueous Medium under Heating

International Letters of Chemistry Physics and Astronomy ◽

10.18052/www.scipress.com/ilcpa.58.1 ◽

2015 ◽

Vol 58 ◽

pp. 1-8

Author(s):

A.B.M. Nazmul Islam

Keyword(s):

Particle Size ◽

Silver Nanoparticles ◽

Particle Size Distribution ◽

Size Distribution ◽

Sodium Dodecyl ◽

Homogeneous System ◽

Nonaqueous Medium ◽

Silver Particles ◽

Force Microscopy ◽

Atomic Force

Chitosan-silver nanoparticles are prepared in nonaqueous medium. In this work, sodium dodecyl sulfate (SDS) was introduced into the dimethylformamide (DMF) solution during silver reduction from solution of its precursor salt AgNO3, acting as a stabilizing agent to prevent aggregation of silver nanoparticles, while chitosan is used as the solid support to embedded silver particles therein, resulting in chitosan-silver (CS-Ag) nanoparticle as suspension in the medium. The reaction started as homogeneous system which turned into heterogeneous with the formation of particles. The properties of CS-Ag nanoparticles are studied under two different salt concentrations and characterized by atomic force microscopy (AFM), scanning electron microscopy (SEM), fourier transform infrared spectroscopy (FTIR) and ultraviolet-visible spectroscopy (UV-Vis). Wide particle size distribution of synthesized nanoparticles depicts that concentration of AgNO3, which is responsible for the morphology, stability and particle size distribution, should be optimized, suggesting a lower salt concentration is favorable.

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The Influence of Groundwater on the Stability of Silica Colloids

MRS Proceedings ◽

10.1557/proc-1193-437 ◽

2009 ◽

Vol 1193 ◽

Cited By ~ 2

Author(s):

Pirkko Holtta ◽

Mari Lahtinen ◽

Martti Hakanen ◽

Jukka Lehto ◽

Piia Juhola

Keyword(s):

Particle Size ◽

Zeta Potential ◽

Particle Size Distribution ◽

Size Distribution ◽

Colloidal Silica ◽

Silica Sol ◽

Low Salinity ◽

Silica Concentration ◽

Silica Colloids ◽

The Stability

AbstractNon-cementitious grouts have been tested in Olkiluoto for the sealing of fractures with the small hydraulic apertures. A promising non-cementitious inorganic grout material for sealing the fractures with the apertures less than 0.05 mm is commercial colloidal silica called silica sol. The potential relevance of colloid-mediated radionuclide transport is highly dependent on their stability in different geochemical environments. The objective of this work was to follow stability of silica sol colloids in low salinity Allard and saline OLSO reference groundwater (pH 7–11) and in deionized milliQ water. Stability of silica sol colloids was followed by measuring particle size distribution, zeta potential, colloidal and reactive silica concentrations. The particle size distributions were determined applying the dynamic light scattering (DLS) method and zeta potential based on dynamic electrophoretic mobility. The colloidal silica concentration was calculated from DLS measurements applying a calibration using a standard series of silica sol. Dissolved reactive silica concentration was determined using the molybdate blue (MoO4) method.These results confirmed that the stability of silica colloids dependent significantly on groundwater salinity. In deionized water, particle size distribution and zeta potential was rather stable except the most diluted solution. In low salinity Allard, particle size distribution was rather constant and the mean particle diameter remained less than 100 nm. High negative zeta potential values indicated the existence of stable silica colloids. In saline OLSO, particle size distribution was wide from a nanometer scale to thousands of nanometers. The disappearance of large particles, decrease in colloidal particle concentration and zeta potential near zero suggest flocculation or coagulation. Under prevailing saline groundwater conditions in Olkiluoto silica colloids released from silica sol are expected to be instable but the possible influence of low salinity glacial melt water has to be considered.

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Determination of Critical Parameters of Drug Substance Influencing Dissolution: A Case Study

BioMed Research International ◽

10.1155/2014/929248 ◽

2014 ◽

Vol 2014 ◽

pp. 1-9 ◽

Cited By ~ 4

Author(s):

Erika Bojnanska ◽

Michal Kalina ◽

Ladislav Parizek ◽

Eva Bartonickova ◽

Tomas Opravil ◽

...

Keyword(s):

Particle Size ◽

Zeta Potential ◽

Particle Size Distribution ◽

Dissolution Rate ◽

Size Distribution ◽

Drug Product ◽

Drug Formulation ◽

Drug Substance ◽

Critical Parameters ◽

Dissolution Profile

The purpose of this study was to specify critical parameters (physicochemical characteristics) of drug substance that can affect dissolution profile/dissolution rate of the final drug product manufactured by validated procedure from various batches of the same drug substance received from different suppliers. The target was to design a sufficiently robust drug substance specification allowing to obtain a satisfactory drug product. For this reason, five batches of the drug substance and five samples of the final peroral drug products were analysed with the use of solid state analysis methods on the bulk level. Besides polymorphism, particle size distribution, surface area, zeta potential, and water content were identified as important parameters, and the zeta potential and the particle size distribution of the drug substance seem to be critical quality attributes affecting the dissolution rate of the drug substance released from the final peroral drug formulation.

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Characterization of kaolin dispersion using acoustic and electroacoustic spectroscopy

Journal of Mining and Metallurgy Section B Metallurgy ◽

10.2298/jmmb0801063d ◽

2008 ◽

Vol 44 (1) ◽

pp. 63-72 ◽

Cited By ~ 16

Author(s):

Z. Dohnalová ◽

L. Svoboda ◽

P. Sulcová

Keyword(s):

Particle Size ◽

Zeta Potential ◽

Particle Size Distribution ◽

Size Distribution ◽

Divalent Cations ◽

Dispersing Agent ◽

Time Period ◽

Ultrasonic Techniques

The objective of this work is the investigation of the kaolin dispersion by the ultrasonic techniques. In contact with aqueous solution clay minerals show cation - exchange properties and certain degree of dissolution or rather selective leaching of components. The work is divided into two main parts - determination of zeta potential and particle size distribution. The first part is focused on measuring of zeta potential. Effects of concentration of solid, different kind of electrolytes (0.01 M KCl, 0.01 M MgCl2 and 0.01 M CaCl2), pH and temperature of the dispersions are investigated. The isoelectric points (IEP) of kaolin suspension are about pH 4-5. Electrolytes containing monovalent cations such as K+ become zeta potential more negative compared to the values obtained with water. Such behavior is explained by the exchange of K+ ions with H+ ions in the system. When the electrolyte is formed by divalent cations such as Mg2+ or Ca2+, the values of zeta potential become less negative than zeta potential of kaolin in water. The second part is focused on the determination of particle size distribution with respect to dispersing conditions, such as the optimal dispersing agent (Na2SiO3, (NaPO3)6, Na4P2O7 or Busperse), time and power of ultrasonication and also the tracking of dispersion stability that is expressed by the measuring of particle size distribution during certain time period.

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