Egg-shells of hen were collected in bulk. They were cleaned mechanically by de - ionized water
and boiled in water for 20 minutes. They were then placed in a furnace for a three-stage thermal
treatment. Heating rate and soaking time at these three stages are given in Table I. Experimental
setup for this synthesis is shown in Fig. 1.
In first stage the eggshell heated upto 450 0C at the heating rate 70C/min. followed by soaking for
two Hrs at 4500C. Similarly in second stage eggshells were heated from 450-6000C at heating