Ceramics-Silikáty 35, (1) 53 - 66 (1991)

The effect of 2M solutions of alkali hydroxide and carbonates on vanadium glasses at 90 °C and under hydrothermal condition at 180 °C were studied. X-ray analysis and scanning electron microscopy showed that in dependence on the composition of the glasses and the solutions, the hydrothermal decomposition at 180 °C yields analcime, feldspars, foids, clay minerals and cancrinite. The reactions at lower temperature (90 °C) produced, apart from sodalite, above all the zeolitic phases phyllipsite, chabazite, analcime and synthetic zeolites P_c, A, KH F. The crystals of the products in soar as they were well identifiable by electron microscopy, were analyzed for the content for vanadium: the highest content was found in analcime (3-10%), zeolites A and H (1-2%) and virtually no vanadium wa. determined in phlillipsite and synthetic zeolite P_c (˂ 1%).