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MFI |
[B] ZSM-5 |
Si(98), B(2) |
Contributed by Rob de Ruiter
Verified by Z. Gabelica, by U. Deforth, and by A. Cichocki
Type Material Na0.4(TPA)0.4[B2Si94O192] : wH2O (TPA = tetra-n-propylammonium)
Method R de Ruiter, J. C. Jansen, H. van Bekkum [1]
Batch Composition 2.1 Na2O : B2O3 : 2.4 SiO2 : 4 TPABr: 1050 H2O
Source Materials
distilled water
silica (Aerosil 200-Degussa)
sodium hydroxide (J. T. Baker, reagent grade)
tetrapropylammonium bromide (TPABr)(CFZ Zaltbommel)
boric acid (Merck p.a.)
Batch Preparation (0.12 to 0.14 g product/35 mL autoclave)
(1) [280 g water + 2.66 g silica + 3.1 g sodium hydroxide], shake overnight at room temperature
(2) [(1) + 19.7 g tetrapropylammonium bromide], stir until dissolved
(3) [90 g water + 2.92 g boric acid], stir until dissolved
(4) [20 mL of (2) + 5 ml. of (3)], mix thoroughly; initial pH ~11
Crystallization
Vessel: Teflon-lined stainless steel autoclave, 35 mL
Time: 5 days
Temperature: 180¼C
Agitation: none
Product Recovery
(1) Filter and wash
(2) Yield: 60-70% on SiO2
Product Characterization
XRD: Pure MFI, no extraneous phases
Elemental Analysis: 93.5% SiO2, 1.25% B203, 2% TPABr, 0.25% Na2O
Crystal Size and Habit: prismatic to lath morphology depending on boron content, the crystal thickness (in b-direction) decreases with boron content of framework
Click here to view XRD pattern
Reference
[1] R. de Ruiter, J. C. Jansen, H. van Bekkum, in Synthesis of Microporous Materials, Vol. 1, M. L Occelli, H. F, Robson (eds.), Van. Nostrand Reinhold, New York, 1992, p 167