Hydrothermal alteration of phillipsite in 3N chloride brines of Li+, Na+, K+, NH4+, Rb+, Cs+, Mg2+, Ca2+, Sr2+, Ba2+, Al2+, Fe3+, La3+, and Nd3+ was investigated at 300° C under a confining pressure of 30 MPa. Phillipsite altered to α spodumene in LiCl, to analcime and albite in NaCl, to orthoclase and leucite in KCl, NH4+-phillipsite in NH4Cl, to RbAlSi2O6 in CsCl, to wairakite in CaCl2, to Ba2+-phillipsite in BaCl2 and Sr-zeolite in SrCl2 under the slightly acidic to neutral conditions (pH 5-7) resulting at 300° C from these brines. Cation exchange appears to be the initial step in all the above transformations. Phillipsite altered to smectite under moderately acidic conditions (∼ pH 4.0) resulting at 300° C from MgCl2, LaCl3, and NdCl3 brines. Phillipsite alteration to smectite proceeds with the initial hydrolysis of Mg2+, La3+, and Nd3+ cations leading to acidic conditions followed by phillipsite dissolution and recrystallization to smectite. Under the extreme acidic conditions (pH 0.3-0.4) developed by the hydrolysis of Fe3+ and Al3+ cations, phillipsite altered to pyrophyllite and pyrophyllite plus kaolinite respectively by dissolution of phillipsite and recrystallization.
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Condensed Matter Physics
- Mechanics of Materials
- Mechanical Engineering