CIT-1. A new molecular sieve with intersecting pores bounded by 10- and 12-rings
- California Inst. of Technology, Pasadena, CA (United States)
A new borosilicate molecular sieve, CIT-1, is synthesized using N,N,N-trimethyl-(-)-cis-myrtanylammonium (1) hydroxide as the organic structure-directing agent. The material is characterized by synchrotron X-ray powder diffraction (XRD), electron diffraction, solid-state NMR and IR spectroscopies, scanning electron microscopy, and physical adsorption experiments. Rietveld refinement of the synchrotron XRD data (Rp = 9.9%, Rwp = 11.9%) shows that CIT-1 is essentially the pure polymorph B of the molecular sieve SSZ-33 (space group C2/m, no. 12, a = 22.6242(10) A, b = 13.3503 (4) A, c = 12.3642 (6) A, and {beta} = 68.913(4){degree}). CIT-1 is the first synthetic molecular sieve to contain intersecting 10- and 12-ring pores that is not an intergrowth of two different polymorphs. The long-range ordering of CIT-1 is shown to be a direct consequence of the organic structure-directing agent. CIT-1 can be easily prepared and sequential treatments of the calcined form of CIT-1 with aqueous HCl, and aqueous aluminum nitrate remove framework boron and insert aluminum into the structure, respectively. Aluminum-containing CIT-1 is a very active catalyst for the cracking of n-butane at 783 K. 35 refs., 10 figs., 6 tabs.
- Sponsoring Organization:
- USDOE
- OSTI ID:
- 81292
- Journal Information:
- Journal of the American Chemical Society, Vol. 117, Issue 13; Other Information: PBD: 5 Apr 1995
- Country of Publication:
- United States
- Language:
- English
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