4A and P zeolites were thermally treated to dehydrate them to differen
t extents. The residual water content and calcium exchange capacity (C
EC) values of the treated zeolites were evaluated. The study revealed
that the CEC of the zeolites depended upon the zeolitic water level. A
nhydrous zeolites are devoid of exchange capacity. Mixed zeolites demo
nstrated mineralisation effect and an additional peak in the thermal s
tudies. (C) 1997 Elsevier Science B.V.