Synthesis and characterization of chromia‐pillared layered tetratitanate

The first chromia-pillared layered tetratitanate was prepared by the reaction of layered tetramethylammonium tetratitanate with chromium (III) acetate [Cr(OAc)3] aqueous solution and subsequent calcination of the resultant solid product in air at 400°C. The obtained chromia-pillared layered tetratitanate has an interlayer distance of 1.06 nm and a high thermal stability up to 600°C. It was also found that calcination in N2 led to the chromia-pillared layered tetratitanate with relatively higher Brunauer-Emmett-Teller (BET) specific surface area (93.9 m2·g−1) and smaller average pore diameter (4.44 nm) than that in air (82.0 m2·g−1, 7.61 nm). Both Bronsted and Lewis acid sites (mainly Lewis type) are present on the chromia-Pillared layered tetratitanate (500°C, N2, 8 h) and strong enough to still remain a small proportion of pyridine upon outgassing at 250°C. Moreover, ammonia temperature-programmed desorption (NH3-TPD) result showed that there were three NH3 desorption peaks at 160, 200 and 315°C, respectively. The corresponding acid amount is 41.3, 73.9 and 290.7 μmol·g−1. The total acid amount is 405.9 μmol·g−1.

[1]  Young-Seok Park,et al.  Thermoelectric power of a single-phase HgBa2Ca2Cu3Oy superconductor , 1995 .

[2]  Q. Yan,et al.  Synthesis and characterization of alumina-pillared layered tetratitanates with different interlayer spacings , 1995 .

[3]  Q. Yan,et al.  Preparation of silica-pillared layered tetratitanate with a high surface area , 1994 .

[4]  A. Jiménez-lópez,et al.  Pillared Clays Prepared from the Reaction of Chromium Acetate with Montmorillonite , 1993 .

[5]  A. Jiménez-lópez,et al.  Porous chromia-pillared α-tin phosphate materials , 1991 .

[6]  G. W. Kirker,et al.  Preparation of molecular sieves from dense layered metal oxides , 1991 .

[7]  A. Jiménez-lópez,et al.  Porous chromia-pillared α-zirconium phosphate materials prepared via colloid methods , 1991 .

[8]  S. Cheng,et al.  Pillaring of layered titanates by polyoxo cations of aluminum , 1989 .

[9]  F. Figueras,et al.  Pillared Clays as Catalysts , 1988 .

[10]  T. Pinnavaia,et al.  New chromia pillared clay catalysts , 1985 .

[11]  K. Sing.  Reporting physisorption data for gas/solid systems with special reference to the determination of surface area and porosity (Recommendations 1984) , 1985 .

[12]  S. Matsuda,et al.  Titanium oxide based catalysts - a review , 1983 .

[13]  S. Kikkawa,et al.  Formation and properties of n-alkylammonium complexes with layered tri- and tetra-titanates , 1983 .

[14]  J. Thomas.  3 – Sheet Silicate Intercalates: New Agents for Unusual Chemical Conversions⊃ , 1982 .

[15]  G. Brindley,et al.  A study of hydroxy-chromium montmorillonites and the form of the hydroxy-chromium polymers , 1979 .

[16]  Y. Watanabe,et al.  Selective Reduction of Nitrogen Oxides In Combustion Flue Gases , 1978 .

[17]  S. C. Fung,et al.  Strong metal-support interactions. Group 8 noble metals supported on titanium dioxide , 1978 .

[18]  Yu. V. Belokopytov,et al.  An infrared study of surface properties of metal oxides: I. The interaction of ammonia with the surface of Cr2O3 , 1976 .

[19]  A. Zecchina,et al.  Infrared study of surface properties of .alpha.-chromia. IV. Pyridine and heavy water adsorption on oxygen-covered surface , 1972 .