|
TON |
ZSM-22 |
Si(95), Al(05) |
Contributed by Gunter Kühl
Verified by M. Derewinski and by Y. Oumi
Type Material K0.1Al0.6Si23.4O48(DAO)0.86a (DAO = 1 ,8-diamino-octane)
Method E. W. Valyocsik [1]
Batch Composition 8.9 K2O : Al2O3 : 90 SiO2 : 3 K2SO4: 27.3 DAO : 3588 H2O
Source Materials
deionized water
aluminum sulfate (99+% Al2(SO4)3 á18 H2O)
potassium hydroxide (87.9% KOH)
1, 8-diamino-octane (99+%)
silica sol (Dupont AS-30, ammonia stabilized, 30% SiO2)
Batch Preparation (for 7.5 g dry product)
(1) [18.2 g water + 1.76 g aluminum sulfate], stir until dissolved
(2) [18.2 g water + 4.0 g potassium hydroxide], stir until dissolved
(3) [72.8 g water + 10.4 g 1,8-diamino-octane], stir until dissolved
(4) [26.95 g water + 47.65 g silica sol], mix well
(5) [(1) + (2)], mix well
(6) [(3) + (5)], add (3) to (5); blend
(7) [(4) + (6)], add (4) to (6), stir for 30 minutesb
Crystallization
Vessel: stirred autoclave with stainless steel liner
Incubation: 24 hours at room temperaturec
Temperature: 1600C
Time: 2-3 days
Agitation: vigorous stirringd
Product Recovery
(1) Dilute reaction mixture with water
(2) Filter and wash with water
(3) Dry at ambient temperature or at 110¡C
(4) Yield: 7.5 g (near 100% on Al2O3)
Product Characterization
XRD: TON; competing phase: MEL (trace)d
Elemental Analysis: 0.2 K2O : Al2O3 : 39 SiO2 : 1.44 DAO
Crystal size and habit: needles e
Click here to view XRD pattern
Reference
[1] E. W. Valyocsik, US Patent 4 902 406
Notes
a. Missing cations assumed to be protonated DAO.
b. Reaction mixture becomes cloudy but does not gel.
c. It is not certain that aging (or seeding) is beneficial.
d. Ref. [1] recommends a stirring rate of 400 rpm; static preparations or slow stirring produce MEL or mixtures of MEL + TON.
e. The size of the crystallites decreases with increasing stirring rate.