PHILLIPSITE ALTERATION IN HYDROTHERMAL BRINES.

Article abstract of DOI:10.1016/0025-5408(87)90126-7

Hydrothermal alteration of phillipsite in 3N chloride brines of Li** plus , Na** plus , K** plus , NH//4** plus , Rb** plus , Cs** plus , Mg**2**+30,Ca**2** plus , Sr**2 ** plus , Ba**2** plus , Al**2** plus , Fe**3** plus , La**3** plus , and Nd**3** plus was investigated at 300 degree C under a confining pressure of 30 MPa. Phillipsite altered to anhydrous and/or hydrous phases such as feldspars, leucite, analcime, Sr-zeolite, etc. in non-acidic brines, to hydroxylated phases such as smectite in moderately acidic brines and to pyrophyllite and kaolinite in extremely acidic brines under hydrothermal conditions. Cation exchange appears to be the initial step in the transformations.