Influence of Alkali on Zeolite Modification I. Zeolite 13 X

Regional Research Laboratory, Jorhat, Assam

Manuscript received 24 April 1978, accepted 27 July 1978

The effect on the thermochemical properties of zeolite 13 X on prolonged contact with alkaline solution has been studied. Solubility of zeolite 13 X is quite small in 2N alkali, but change in chemical composition with decrease of SiO₂/Al₂O₂ ratio and increase of cation content was observed due to preferential dissolution of silica from zeolite. The zeolite does not undergo structural change but becomes contaminated with other aluminosilicate material formed due to recombination of aluminate and silicate ions in solution.