PREPARATION OF ALPHA-QUARTZ BY THE THERMA L-DEGRADATION OF SILICON DIOXIDE-TRIETHYLAMINE(3 2)/

High purity alpha-quartz was prepared by calcination of silicon dioxid e-triethylamine (3/2) at 1000 degrees C for 24 h in air. Silicon dioxi de-triethylamine (3/2) was obtained by the reaction of triethylamine a nd silicic acid in a tetrahydrofuran (THF) solution for 24 h at room t emperature. The compound was confirmed to be 2 (C2H5)(3)N . 3 SiO2 by the elemental analysis, infrared specturm and the thermogravimetric an alysis. Impurity of sodium, potassum, iron and aluminium was not detec ted by atomic absorption analysys of alpha-quartz synthesized, a no ur anium as impurity was also detected by fluorescence analysis. Reaction was considered as follows. 3 H4SiO4 + 2 (C2H5) N-3-->2 (C2H5)(3)N . 3 SiO2 + 6 H(2)O2 (C2H5)(3)N . 3 SiO2+211/2O(2)-->3 SiO2 + 12 CO2 + 15 H2O + 2 NO2