Titanium dioxide dispersion

Pigment Dispersion. The alkan olamines and thek derivatives are useful in dispersing titanium dioxide and other pigments (209). Monoisopropanolamine and triethanolamine are particularly effective in aiding titanium dioxide dispersion in the production of Ti02 and in water-based paints (210). The alkan olamines are also an aid in the grinding of titanium dioxide (211). 

Borgarello E, Serpone N, Emo G, Harris R, Pelizzetti E, Minero C (1986) Light-induced reduction of rhodium (III) and palladium (II) on titanium dioxide dispersions and the selective photochemical separation and recovery of gold (III), platinum (IV) and rhodium (III) in chloride media. Inorg Chem 25 4499-4503... 

It appeared attractive to extend the work on emulsification of liquid-liquid systems by BG copolymers to solid-liquid systems. As a first approach a model system was studied which comprises titanium dioxide dispersed in toluene with modified styrene-butadiene block copolymers as dispersants. These studies are reported here. 

Augugliaro, V. Davi, E. Palmisano, L. Schiavello, M. Sclafani, A. Influence of hydrogen peroxide on the kinetics of phenol photodegradation in aqueous titanium dioxide dispersion, Appl. Catal. 1990, 65, 101. 

Apart from latexes, S-FFF has been used to fractionate and determine the size distribution of numerous industrial colloids including water-based titanium dioxide dispersions [6,171], carbon black dispersions [6],phthalocyanineblue [6], various silica sols [141,171,176], gold and silver sols [385], pigments, metal and ceramic particles, clay and a host of latexes [294]. Gold, palladium, silver and copper particles in the size range 0.3-15 pm were separated by steric-S-FFF and their size distributions determined in less than 12 min [69]. 

Dukhin and Goetz [253] found a non-linear attenuation spectra for rutile titanium dioxide dispersions in the volume concentration range 1% to 42% and developed a theory to account for this. Dukhin et al. [254] state that viscous losses are dominant in high density contrast dispersions e.g. rutile whereas thermal losses are dominant in low-density contrast dispersions e.g. latices. A report of two years experience of operating this instrument was reported by Hinze et.al. [255]. 

When referring to Ti02-based photocatalytic systems it is important to note that, in most cases, the semiconducting oxide is associated there with a noble metal or/and a noble metal oxide catalyst. While the role played by these catalysts in (partial) cathodic reactions seems relatively well understood it remains less clear with regard to the photoanodic reactions. In particular, the exact function of the extensively used ruthenium dioxide catalyst has been questioned The role of Ru02 as a hole-transfer catalyst has, for example, been established through laser-photolysis kinetic studies in the case of photo-oxidation of halide (Br and CP) ions in colloidal titanium dioxide dispersions. In fact, the yields of Brf and ClJ radical anions, photogenerated in the course of these reactions. 

Chandramalar, A.V.M. et al.. Flow behaviour of titanium dioxide dispersions in the presence of 2-hydroxyethyl cellulose. Colloid Polym. Sci., TT, 485, 2000. 

Novoblanc A. [Sigma Prodotti Chimici] Titanium dioxide dispersion white pig-... 

Light Duller NF. [Sybton] Titanium dioxide dispersion ddusterant fix textile fibos. 

Augugliaro, V., Paltnisano, L., Sclafani, A., Minero, C and Pelizzetti, E., 1988, Photocatalytic degradation of phenol in aqueous titanium dioxide dispersions, Toxicol. Environ. Chem., 16(2) 89-109. 

So-called microencapsulated electronic inks have received much publicity in recent years. They consist of microencapsulated electrophoretic media that change color (eg, black to white) when an electric field is applied to thin microcapsule layers placed between thin electrodes. This color change occurs because the microcapsules contain a mixture of two color components dispersed in a dielectric fluid. The two color components can conceptually be two different colored particles (eg, white titanium dioxide and carbon black) or particles of one color (eg, titanium dioxide) dispersed in a dyed dielectric fluid. In either case, application of an external electrical field causes the color components to migrate or separate inside the microcapsules, thereby forming different colored images. Such inks make it possible to create flexible electronic paper displays that require low power and can receive and display information electronically (34-36). 

Marchant, J. Q. and Wakeman, R. J., Crossflow microfiltration of concentrated titania suspensions , Proc. IChemE Jubilee Research Event, Vol.2,1061,Nottingham(1997) Mikulasek, P., Wakeman, R. J. and Marchant, J. Q., Crossflow Microfiltration of Shear-Thinning Aqueous Titanium Dioxide Dispersions , Chem. Eng. J., 69, 53 (1998)... 

Glass JE (1999) Adsorption of hydrophobically modified, ethoxylated urethane thickeners on latex and titanium dioxide disperse phases. Adv Colloid Interface Sci 79 123-148... 

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