Contributed by David Hayhurst

Verified by A. Cichocki, by A. Rodriguez, by E. Falabella Sousa-Aguiar, and by R. Thompson and A. Giaya

Type Material K₃.₁Na_0.9[Al₁₁Si₁₂O₃₂] : wH₂O

Method D. T. Hayhurst, L B. Sand [1]

Batch Composition 6.95 Na₂O : 3.50 K₂O : Al₂O₃ : 18.5 SiO₂ : 325 H₂O

Source Materials

distilled water
potassium hydroxide (Mallinckrodt reagent grade, 87% KOH)
sodium silicate solution (PQCorp., N-brand, 8.9% Na₂O, 28.7% SiO₂)
sodium aluminate (Nalco, 30.5% Na₂O, 45.6% Al₂O₃)

Batch Preparation (for 100 g dry product)

(1) [636 g water + 91.6 g potassium hydroxide + 826.9 g sodium silicate solution]. Dissolve in a stirred flask at 100¡C under reflux
(2) [(1) + 45.28 g sodium aluminate], continue mixing at 100¡C for crystallization

Crystallization

Vessel: 3 L, 3-neck flask under reflux
Temperature: 100¡C
Time: 6 to 8 hours
Agitation: mechanically stirred

Product Recovery

(1) Filter to recover solids
(2) Wash to pH<10
(3) Dry at 120¡C
(4) Yield: 100% on Al₂O₃

Product Characterization

XRD: PHI (only crystalline product); Competing phases; MOR,^a ERI,^a LTL,^b GIS,^b ANA^c
Elemental Analysis: 0.8 K₂O. 0.2 Na₂O . Al₂O₃ : 5.24 SiO₂
Crystal Size and Habit: multi-crystalline aggregates, ~5 um dia.
Click here to view XRD pattern

Reference

[1] D. T. Hayhurst, L B. Sand, in ACS Symposium Series 40, 1. R Katzer (ed.), Am. Chem. Soc., Washington, D. C., 1977, p. 219

Notes

a. Higher silica batch composition

b. K⁺/(Na⁺ + K⁺) > 0.4

c. K⁺/(Na⁺ + K⁺) <0.1