Leaching of the Anthraquinone Dye Solvent Blue 59 Incorporated into Organically Modified Silica Xerogels
- 73 Downloads
The effects of preparation method and precursor composition on the leaching behavior of the anthraquinone dye Solvent Blue 59 incorporated into silica based xerogels have been studied. Xerogels were prepared under acidic conditions from mixtures of 20 mol% of organically modified silicon alkoxides, R′–Si(OR)3, in Si(OR)4 (R = methyl or ethyl, R′ = methyl, vinyl, phenyl). The dye was added at the beginning of the sol-gel reaction. The reaction was carried out by either hydrolysis under acidic conditions or acidolysis by formic acid. The dye incorporated was leached with refluxing ethanol using a Soxhlet extraction procedure to simulate the long-term stability of the samples prepared. With increasing size of organic substituent (methyl < vinyl < phenyl), the amount of dye leached decreases. Results from nitrogen adsorption experiments show that all samples characterized have about the same average pore diameter, but they differ in total pore volume and BET surface area. With increasing size of the organic residue, the pore volume decreases by an order of magnitude. Therefore, it is concluded that the microstructure of the xerogels prepared determines the retention behavior of dyes incorporated during the sol-gel reaction.
Unable to display preview. Download preview PDF.
- 1.D. Avnir, D. Levy, and R. Reisfeld, J. Phys. Chem. 88, 5956 (1984).Google Scholar
- 2.U. Narang, R. Wang, P.N. Prasad, and F.V. Bright, J. Phys. Chem. 98, 17 (1994).Google Scholar
- 3.R.A. Dunbar, J.D. Jordan, and F.V. Bright, Anal. Chem. 68, 604 (1996).Google Scholar
- 4.W.P. Hsu, R. Yu, and E. Matijevic, Dyes and Pigments 19, 179 (1992).Google Scholar
- 6.O. Lev, M. Tsionsky, L. Rabinovich, V. Glezer, S. Sampath, I. Pankratov, and J. Gun, Anal. Chem. 67, 22 A (1995).Google Scholar
- 7.L. Sieminska and T.W. Zerda, J. Phys. Chem. 100, 4591 (1996).Google Scholar
- 8.I.J.M. Snijkers-Hendrickx and J. van den Ven, in Proceedings of the XVIIth International Congress on Glass (Chinese Ceramic Society, Beijing 1995), Vol. 4, p. 9.Google Scholar
- 9.J.-C. Panitz and A. Wokaun, J. Sol-Gel Sci. Tech. 9, 251 (1997).Google Scholar
- 10.K.G. Sharp, J. Sol-Gel Sci. Tech. 2, 35–41 (1994).Google Scholar