Selective Spectrophotometric Determination Of Trace Amounts Of Chromium(vi) Using A Flow Injection System With A Microcolumn Of Zirconium(iv) Oxide Modified Silica Gel

Zirconium(IV) oxide coated on a silica gel surface was found to be very effective for extracting CrVI from aqueous solutions at a pH of about 3. A microcolumn packed with this material was inserted into a flow injection system for the separation and preconcentration of CrVI. By this process, a concentration level of 2 ppb was detected with a relative standard deviation of 2.4%. Because of the high selectivity of the immobilized substrate, it was possible to determine CrVI in the presence of larger amounts of other ions. The analysis was also carried out on natural water spiked with CrVI, and compared with a standard method.11761029103

Use Of α-cellulose Coated With Titanium(iv) Oxide In Separation Of Crvi

α-Cellulose reacted with TiCl4 was hydrolyzed to obtain a TiO2 coating on the biopolymer surface. CrVI in a concentration range between 10 and 50 ppb was separated from CrIII using a column packed with this material. The presence of other ions such as CuII, MnII, HgII, and FeIII, and the anions VO3 3-, MoO4 2-, PO4 3-, and SO4 2-, did not interfere significantly in the separation process.31810451057Kennedy, J.F., Cabrai, J.M.S., (1985) Transition Met. Chem., 11, p. 41Yates, D.E., Wely, T.W., (1980) J. Chem. Soc., Faraday I, 76, p. 9Strelko, V.V., Khainakov, S.A., Kvashenko, A.P., Belyakov, V.N., Bortun, A.I., (1988) J. Appl. Chem., USSR, 61, p. 1922Kubota, L.T., Gushikem, Y., Moreira, J.C., (1991) Analyst, 116, p. 281Gushikem, Y., Peixoto, C.R.P., Kubota, L.T., (1991) New Developments in Ion Exchange Materials. Fundamentals and Applications, p. 607. , M. Abe, T. Kataoka, and T. Suzuki, Eds., Kodansha-Elsevier, TokyoKurokawa, Y., Ohta, H., Okubo, M., Takahashi, M., (1994) Carbohydr. Polym., 23, p. 1Fujii, T., Suzuki, M., (1991) New Developments in Ion Exchange Materials. Fundamentals and Applications, p. 355. , M. Abe, T. Kataoka, and T. Suzuki, Eds., Kodansha-Elsevier, TokyoInagaki, H., Phillips, G.O., (1989) Cellulosics Utilization: Research and Rewards in Cellulosics, , Elsevier Applied Science, LondonIvanova, N.Y., Korolenko, E.A., Korolik, E.V., Zhbankov, R.G., (1989) J. Appl. Spectrosc., 52, p. 847Sihtola, H., Neimo, L., (1975) Symposium on Enzyme Hydrolysis of Cellulose, p. 9. , Sitra, HelsinskiJohnson, C.A., (1990) Anal. Chim. Acta, 238, p. 273Burns, D.T., Harriott, M., Barakat, S.A., (1992) Anal. Chim. Acta, 259, p. 33Elleouet, C., Quentel, F., Madec, C., (1992) Anal. Chim. Acta, 257, p. 301Jørgensen, S.S., Regitano, M.A.B., (1980) Analyst, 105, p. 292Andrade, J.C., Rocha, J.C., Baccan, N., (1985) Analyst, 110, p. 197Ruz, J., Rios, A., Castro, M.D.L., Valcárcel, M., (1986) Anal. Chim. Acta, 186, p. 139Sperling, M., Yin, X., Welz, B., (1992) Analyst, 117, p. 629Cox, A.G., Cook, I.G., McLeod, C.W., (1985) Analyst, 110, p. 331Peixoto, C.R.M., Gushikem, Y., Baccan, N., (1992) Analyst, 117, p. 1029Abe, M., Wang, P., Shitrakar, R., Tsuji, M., (1989) Analyst, 114, p. 435Baes, C.F., Mesmer, R.E., (1976) The Hydrolysis of Cations, p. 229. , Wiley, New Yor

Electrochemical Properties Of [ru(edta)(h2o)]- Immobilized On A Zirconium (iv) Oxide-coated Silica Gel Surface

[Ru(edta)(H2O)]- is strongly adsorbed on a zirconium(IV) oxide-coated silica gel surface. The immobilized complex showed an electrochemical response due to the Ru(II)/Ru(III) redox couple. By substituting the coordinated water molecule in the adsorbed complex, the midpoint potentials shifted in the order (in mV) water, -290; thiocyanate, -200; pyridine, -180; 4-cyanopyridine, -80: and pyrazine, -50 vs SCE.1841236240Steiger, B., Anson, F.C., (1994) Inorg. Chem., 33, p. 5767Abruna, H.D., (1988) Coord. Chem. Rev., 86, p. 135Barisci, J.N., Wallace, G.G., (1991) Anal. Lett., 24, p. 2059Cassidy, J.F., Vos, J.G., (1988) J. Electrochem. Soc., 135, p. 863Zaldivar, G.A.P., Gushikem, Y., (1992) J. Electroanal. Chem., 337, p. 165Kubota, L.T., Gushikem, Y., (1993) J. Electroanal. Chem., 362, p. 219Zaldivar, G.A.P., Gushikem, Y., Benvenutti, E.V., De Castro, S.C., Vasquez, A., (1994) Electrochim. Acta, 39, p. 33Da Cunha, L.J.V., Andreotti, E.I.S., Gushikem, Y., (1995) J. Braz. Chem. Soc., 6, p. 271Peixoto, C.R.M., Kubota, L.T., Gushikem, Y., (1995) Anal. Proc., 32, p. 503Kubota, L.T., Gushikem, Y., Perez, J., Tanaka, A.A., (1995) Langmuir, 11, p. 1009Milagres, B.G., Kubota, L.T., De Oliveira Neto, G., (1996) Electroanalysis, 8, p. 689Shimizu, K., Matsubara, T., Satô, G.P., (1974) Bull. Chem. Soc. Jpn., 47, p. 1651Bajaj, H.C., Van Eldik, R., (1988) Inorg. Chem., 27, p. 4052Matsubara, T., Creutz, C., (1979) Inorg. Chem., 18, p. 1956Matsubara, T., Creutz, C., (1978) J. Am. Chem. Soc., 100, p. 6255Araki, K., Rein, F.N., Camera, S.G., Toma, H.E., (1992) Trans. Met. Chem., 17, p. 535Bajaj, H.C., Van Eldik, R., (1990) Inorg. Chem., 29, p. 2855Oyama, N., Anson, F.C., (1978) J. Electroanal Chem., 88, p. 289Oyama, N., Anson, F.C., (1979) J. Am. Chem. Soc., 101, p. 1634Mukaida, M., Okuno, H., Ishimori, T., (1965) Nippon Kagaku Zasshi, 86, p. 589Perez, J., Tanaka, A.A., Gonzalez, E.R., Ticianelli, E.A., (1994) J. Electrochem. Soc., 141, p. 431Gushikem, Y., Iamamoto, M.S., (1990) J. Colloid Interface Sci., 134, p. 275Veselý, V., Pekárek, V., (1972) Talanta, 19, p. 219Chatterjee, D., Bajaj, H.C., Das, A., (1995) J. Chem. Soc. Dalton Trans., p. 2497Bard, A.J., Faulkner, L.R., (1980) Electrochemical Methods, Fundamentals and Applications, , Wiley, New YorkShigehara, K., Oyama, N., Anson, F.C., (1982) J. Am. Chem. Soc., 103, p. 2552Kubota, L.T., Gushikem, Y., (1993) J. Electroanal. Chem., 362, p. 219Toma, H.E., Creutz, C., (1977) Inorg. Chem., 16, p. 545Shepherd, R.E., Taube, H.E., (1973) Inorg. Chem., 12, p. 139