Titanium dioxide suspensions

Brezova, V., Blazkova, A., Surina, I., and Havlmova, B. (1997) Solvent effect on the photocatalytic reduction of 4-nitrophenol in titanium dioxide suspensions. Journal of Photochemistry and Photobiology A Chemistry, 107 (1-3), 233-237. 

Theurich, J., Linder, M., and Bahnemann, D., Photocatalytic degradation of 4-chlo-rophenol in aerated aqueous titanium dioxide suspensions a kinetic and mechanistic study, Langmuir, 12, 6368, 1996. 

As has been shown by time-resolved flash photolysis measurements in colloidal titanium dioxide suspensions trapping is a very fast process. Rothenberger et al. performed picosecond and nanosecond transient absorption experiments on titanium dioxide and observed that the electron trapping time was faster than 30 ps, the time resolution of their laser system [4e]. The trapping time for holes was estimated to be < 250 ns. In a recent picosecond study by Serpone et al. on titanium dioxide colloids solutions of varying diameters it was observed that the spectra of trapped electrons as well as of trapped holes are fully developed after a laser... 

Ballari, M.M., Brandi, R., Alfano, O., and Cassano, A. (2008) Mass transfer limitations in photocatalytic reactors employing titanium dioxide suspension. I. concentration profiles in the bulk. Chemical Engineering Journal, 136, 50-65. 

Stevenson, M. Bullock, K. Lin, W.-Y. Rajeshwar, K. Sonolytic enhancement of the bacterial activity of irradiated titanium dioxide suspensions in water. Res. Chem. Intermed. 1997, 23, 311. 

Augugliaro V, Loddo V, Marce G, Palmisano L, Lopez-Munoz MJ. Photocatalytic oxidation of cyanides in aqueous titanium dioxide suspensions. J Catal 1997 166 272-83. 

Koizumi, Y. and Taya, M. (2002) Photocatalytic inactivation rate of phage MS2 in titanium dioxide suspensions containing various ionic species. Biotechnol. Lett. 24,459 162. 

Goutailler G, Valette )-C, Guillard C, Paisse O, Faure R (2001) Photocatalyzed Degradation of Cyromazine in Aqueous Titanium Dioxide Suspensions Comparison with Photolysis, /. Photochem. Photobiol. A Chem. 141 79-84. 

Several authors have addressed the determination of the optical properties of aqueous titanium dioxide suspensions in the context of photoreactor modeling (Brandi et al., 1999 Cabrera et al., 1996 Cured et al., 2002 Salaices et al., 2001, 2002 Satuf et al., 2005 Yokota et al., 1999). Among the determined properties are extinction, scattering, and absorption coefficients, as well as the asymmetry parameter of the scattering phase function. In general the procedures involve fitting of a radiative transfer model to the experimental results for reflectance and transmittance of radiation. 

Schindler, P. W. and Gamsjaeger, H. Acid-base reactions of the titanium dioxide (anatase) - water interface and the point of zero charge of titanium dioxide suspension, Kolloid - Z. Z. Polym. 250, 759-763 (1972). 

Konstantinou IK, Albanis TA. Photocatalytic transformation of pesticides in aqueous titanium dioxide suspensions using artificial and solar light intermediates and degradation pathways. Appl Catal B Environ 2003 42 319-335. 

Furthermore, the transient formation of cation radicals can be observed when a colloidal titanium dioxide suspension is flashed in the presence of an olefin [56]. The flash photolysis experiments also show that the surface influences the subsequent chemistry of the photogenerated intermediate. In fact, oxygenation and isomerization dominated the chemistry observed for tran -stilbene, with the same product distribution obtained upon starting with either the cis or the trans isomer (Eq. 3). 

Later, Papet [58] presented an alternative process for preparing mbular ceramic cross-fiow filtration membranes. Papet s method consists of the casting of mbular mineral microfiltration membranes with titanium dioxide suspensions. The deposited particles on the porous support were then compressed and finally, the layer was consolidated by firing. 

The fact that the photosynthesis of hydrogen peroxide on irradiated titanium dioxide suspensions is manifestly ineffective is easily understood when one examines together the cathodic and the photoanodic behaviour of H2O2 at a Ti02 electrode . Thus, the reduction of the HOJ ions... 

Zhao, Y. et al.. Effects of inorganic salt on ceramic membrane microfiltration of titanium dioxide suspensions.. 1. Membr. Sci., 254, 81, 2005. 

Soltys, M.M. et al., Poly(methacrylic acid) adsorption and electrical surface properties of titanium dioxide suspensions. Ads. Sci. Technol., 20, 633, 2002. 

Dutta, P.K., A.K. Ray, V.K. Sharma, and F.J. Millero. 2004. Adsorption of arsenate and arsenite on titanium dioxide suspensions. Journal of Colloid and Interface Science 278(2004) 270-275. 

Buttler, E. C. and Davis, A. R, 1993, Photocatalytic oxidation in aqueous titanium dioxide suspensions The influence of dissolved transition metals, J. Photochem. Photobiol. A Chem., 70 273-283. 

Pesticides in Aqueous Titanium Dioxide Suspensions Using Artificial and Solar Light Intermediates and Degradation Pathways , Appl. Catal. B-Environ., 2003,42, 319... 

Brezova V, Ceppan M, Brandsteterova E, Breza M, Lapcik L. (1991) Photocatalytic hydroxyl-ation of benzoic acid in aqueous titanium dioxide suspension. J. Photobiol. Photochem., 59 385-391. 

Figure 13. Kinetic data for the coagulation of titanium dioxide suspensions.

Photocatalytic reduction of mercury(ll) and simultaneous oxidative degradation of surfactants in titanium dioxide suspensions... 

Wuang KH, Hsieh YH, Chou MY, Chang CY (1998) Photocatalytic degradation of 2-chloro and 2-nitrophenol by titanium dioxide suspensions in aqueous solution. Appl Catal B Environ 21 1-8... 

Hidaka, H. Ihava, K. Fujita, Y. and Yamada, S. (1988) Photo degradation of Surfactants IV. Photodegradation of non-ionic surfactants in aqueous titanium dioxide suspensions, J. Photochemistry and Photobiology A 42, 375-381. 

In subsequent years, various investigators searched for the Reynolds [61] and Freundlich-Roder [62] effects in concentrated suspensions of small particles. Of special interest are the researches of Metzner and Whitlock [63] and Hoffmann [64]. The former authors [63] described experiments on a titanium dioxide particle suspension of unspecified particle size and suspensions of large glass spheres (28 to 100 pm). Both volumetric dilation and Freundlich-Roder viscosity increases were only observed in the titanium dioxide suspensions, but appeared to occur independently with volumetric dilation occurring at lower shear stresses/rates. 

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