Mineral dispersions

Complexes of tetravalent zirconium with organic acids, such as citric, tartaric, malic, and lactic acids, and a complex of aluminum and citric acid have been claimed to be active as dispersants. The dispersant is especially useful in dispersing bentonite suspensions [288]. Polymers with amine sulfide terminal moieties are synthesized by using aminethiols as chain transfer agents in aqueous addition polymerizations. The polymers are useful as mineral dispersants [1182]. 

Geochemical and mineral dispersal patterns related to drift-covered copper-gold mineralization in central British Columbia, Canada... 

The flotation of minerals is based on different attachment forces of hydrophobized and hydrophilic mineral particles to a gas bubble. Hydrophobized mineral particles adher to gas bubbles and are carried to the surface of the mineral dispersion where they form a froth layer. A mineral is hydrophobized by the adsorption of a suitable surfactant on the surface of the mineral component to be flotated. The hydrophobicity of a mineral particle depends on the degree of occupation of its surface by surfactant molecules and their polar-apolar orientation in the adsorption layer. In a number of papers the relationship was analyzed between the adsorption density of the surfactant at the mineral-water interface and the flotability. However, most interpretations of adsorption and flotation measurements concern surfactant concentrations under their CMC. 

Mineral flotation is a method for selective separation of mineral components out of polymineral dispersions of ground ores in water (ca. 5-35 vol.% of the solid) by using dispersed gas (usually air) bubbles. The method consists in the different adhesion of hydrophobized and hydrophilic mineral particles to an air bubble. Hydrophobized mineral particles adhere to the air bubble and are carried out as a specifically lighter aggregate to the surface of the mineral dispersion where they form a foam (froth) layer. This foam, called concentrate, is mechanically removed (Fig. 1A). A mineral is hydrophobized by adsorption of a suitable surface-active compound (surfactant, collector) on the surface of the mineral component to be flotated. All other nonhydrophobized particles remain dispersed in the mixture (Fig. IB). 

The sTope of the dispersion staining curve is characteristic for each mineral. Dispersion staining curves of various minerals have been plotted in the Particle Atlas (43) and dispersion data are given by Winchell (44). 

Lagaly, G., From clay mineral crystals to colloidal clay mineral dispersions, in Coagulation and Flocculation, Theory and Applications, Surfactant Science Series, 47, Dobias, B., Ed., Marcel Dekker, New York, 1993, p. 427. 

Mikulasek P, Dolecek P, Smidova D, and Pospfsil P. Crossflow microfiltration of mineral dispersions using ceramic membranes. Desalination 2004 163 333-343. 

Use Boiler water compounds, detergents, textiles, leather tanning, photographic film developing, deflocculation of clays, flotation and desliming of minerals, dispersion of pigments, paper processing, industrial and municipal water treatment. 

Graniisol. [Am. Minerals] Dispersing granular micronutrients for fertilizer blending. 

Application of microbicides for the storage protection of mineral dispersions... 

The dispersants, usually based today on salts of polyacrylic acid (PAA), represent a rich supply of organic nutrients for cells. They serve also as both a carbon and energy source. Mineral dispersions, however, also... 

APPLICATION OF MICROBICIDES FOR THE STORAGE PROTECTION OF MINERAL DISPERSIONS... 

The microbiological colonies, as well as their growth in a mineral dispersion, can be influenced by many different factors, such as ... 

Photo 4 Identification of microorganisms found to occur in mineral dispersions. 

An overview of the major microorganisms found to occur in mineral dispersions is shown in Table 1, although it has to be mentioned that only those species which could be repeatedly confirmed by the methods employed by the current authors have been listed, and, therefore, the list is by no means exhaustive. 

Prevention of contamination caused by microorganisms and the effects arising therefrom have economic consequences. These consequences must not be underestimated. For example, significant changes in the rheology of mineral dispersions can lead to a standstill in paper production. Similarly, continual false application of biocide(s) arising from an over-reaction philosophy can have equally dramatic economical effect. 

Must have no negative influence on other mineral dispersion properties. 

Among a large number of bactericidal agents the following ones have proved to be successful as preservatives in mineral dispersions. Once again, this list should not be considered as exhaustive many biocides which have proven efficacy have either fallen out of favour due to regulatory requirements or even environmentally-related perceptions, and many biocides remain to be discovered or, if already existing, to be applied in this field. We go on to consider some currently used biocides and identify a newly applied biocide in this field. 

Since mineral dispersions might be used in the production of food packaging the constituent substances have usually to comply with most of the relevant laws, such as BfR Germany, FDA USA and current and emerging EU directives. 

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