The ion exchange of heavy metals on natural zeolite was carried out using the batch method.
Batch adsorption experiments were conducted using 10 g of adsorbent with 500 ml of solutions containing heavy metal ions of desired concentrations at constant temperatures (25 ◦C) in 500-ml plastic bottles.
The particle size of the sample (clinoptilolite) used was in the range of 63–106 μm. The bottles were shaken in a sieve for 5.5 h and solutions containing heavy metals were filtered through Whatman filter paper (No. 42).
The exact concentration of metal ions and filterable metal concentrations were determined by AAS (ATI UNICAM 929 atomic absorption spectrophotometer).
The flame type was air–acetylene and absorption wavelengths are Cu2+(324.7 nm), Zn2+(213.9 nm), Co2+(240.7 nm), and Mn2+(279.5 nm).