Optimization of the synthesis of mesoporous titanosilicate ETS-10: Problems and unexpected difficulties

  • 1 Institute of mineralogy and crystallography “Acad. Ivan Kostov”, Bulgaria


We focused on the synthesis and subsequent use of mesoporous titanosilicate ETS-10 for industrial water purification. Numerous attempts have been made to optimize the conditions and reagents used for the synthesis of the ETS-10. The main problem we faced in the synthesis of ETS-10 is the production of “pure” phase and it was related to the type of titanium source. Various sources of titanium were used – titanium tetrachloride, anatase (anatase 92% and rutile 6%), nanosized titanium dioxide (Degussa P25) etc. The use of liquid titanium tetrachloride, due to its high hydrophilicity, leads to difficulties in reproducible control of the quantities of used reagents, which leads to the formation of unwanted crystalline phases, especially if the synthesis is carried out in small volumes. In addition, the optimized by us synthesis attempts included a reduced reaction time – up to 24 hours – and lower temperatures (up to 200 oC). For comparison standard synthesis is carried out for 72 h at 230 oC. As a result of the experiments, ETS-10 with minimal SiO2 residues was obtained in 24 hours at 200 oC using nanosized anatase.



  1. Llabrés i Xamena, F.X., et al., Enhancement of the ETS- 10 titanosilicate activity in the shape-selective photocatalytic degradation of large aromatic molecules by controlled defect production. Journal of the American Chemical Society, 2003. 125(8): p. 2264-2271.
  2. Al-Baghli, N.A. and K.F. Loughlin, Adsorption of methane, ethane, and ethylene on titanosilicate ETS-10 zeolite. Journal of Chemical & Engineering Data, 2005. 50(3): p. 843-848.
  3. Zhao, G.X., J.L. Lee, and P.A. Chia, Unusual adsorption properties of microporous titanosilicate ETS-10 toward heavy metal lead. Langmuir, 2003. 19(6): p. 1977-1979.
  4. Kuznicki, S.M., Large-pored crystalline titanium molecular sieve zeolites. 1989, Google Patents.
  5. Kuznicki, S., Preparation of small-pored crystalline titanium molecular sieve zeolites. US patent, 1990. 4(938): p. 939.
  6. Anderson, M., et al., Structure of the microporous titanosilicate ETS-10. Nature, 1994. 367(6461): p. 347- 351.
  7. Ng, Y.-C., C.-Y. Jei, and M. Shamsuddin, Titanosilicate ETS-10 derived from rice husk ash. Microporous and mesoporous materials, 2009. 122(1-3): p. 195-200.
  8. Rocha, J., et al., Synthesis of microporous titanosilicate ETS-10 from TiCl3 and TiO2: a comprehensive study. Microporous and mesoporous materials, 1998. 23(5-6): p. 253-263.
  9. Kostov-Kytin, V., et al., Hydrothermal synthesis of microporous titanosilicates. Microporous and Mesoporous Materials, 2007. 105(3): p. 232-238.
  10. Kr, T., Das, AJ Chandwadkar, AP Budhkar and S. Sivasanker. Microporous Mater, 1996. 5: p. 401.
  11. Yang, X., et al., Synthesis of microporous titanosilicate ETS-10 with TiF4 or TiO2. Microporous and mesoporous materials, 2001. 46(1): p. 1-11.
  12. KerryáThomas, J., Synthesis of microporous titanosilicates ETS-10 and ETS-4 using solid TiO2 as the source of titanium. Chemical Communications, 1996(12): p. 1435-1436.
  13. Kim, W.J., et al., Study on the rapid crystallization of ETS-4 and ETS-10. Microporous and mesoporous materials, 2000. 41(1-3): p. 79-88.
  14. Pavel, C., et al., Synthesis of microporous titanosilicates ETS-10 and AM-2 using Ti2(SO4)3, in Studies in Surface Science and Catalysis. 2004, Elsevier. p. 770-775.
  15. Das, T.K., et al., Studies on the synthesis of ETS-10 I. Influence of synthesis parameters and seed content. Microporous Materials, 1995. 4(2-3): p. 195-203.
  16. Das, T.K., et al., Studies on the synthesis of ETS-10 II. Use of organic templates. Microporous materials, 1996. 5(6): p. 401-410.
  17. Das, T.K., A. Chandwadkar, and S. Sivasanker, A rapid method of synthesizing the titanium silicate ETS-10. Chemical Communications, 1996(10): p. 1105-1106.
  18. Jeong, N.C., Y.J. Lee, and K.B. Yoon, Rapid synthesis of high-quality ETS-10 crystals. Microporous and mesoporous materials, 2008. 115(3): p. 308-313.
  19. Su, L.L.F. and X. Zhao, Synthesis and characterization of microporous titanosilicate ETS-10 with different titanium precursors. Journal of Porous Materials, 2006. 13(3): p. 263-267.
  20. Casado, C., et al., Synthesis and characterization of microporous titanosilicate ETS-10 obtained with different Ti sources. Materials Research Bulletin, 2009. 44(6): p. 1225-1231.
  21. Ji, Z., et al., Hydrothermal synthesis of titanosilicate ETS- 10 using Ti(SO4)2. Microporous and mesoporous materials, 2005. 81(1-3): p. 1-10.
  22. Valtchev, V.P., Influence of different organic bases on the crystallization of titanium silicate ETS-10. Journal of the Chemical Society, Chemical Communications, 1994(3): p. 261-262.
  23. Valtchev, V. and S. Mintova, Synthesis of titanium silicate ETS-10: The effect of tetrametylammonium on the crystallization kinetics. Zeolites, 1994. 14(8): p. 697-700.

Article full text

Download PDF