2.3. Batch adsorption procedure

The batch experiment was performed by adding desired amount of metal solution in 50 mL volumetric flask at desired adsorbent dose, pH, agitation speed and temperature. The solution was transforrmed in to 250 mL conical flask and shaken by mechanical shaker (Digital RJH5005 12-Stand Orbital Shaker) at desired rpm for definite periods. Adsorbent dose, metal ion concentration, contact time, agitation speed, pH, and temperature were optimized by continuous variation approach (studying one parameter keeping the others constant) [17]. The difference in the metal ions concentration before and after adsorption represents the metal ion adsorbed and it was measured using flame atomic absorption spectroscopy (ELICO SL 194, India). The FAAS was adjusted to measure each sample five times and the results taken as an average.