1. Results showed that low cost adsorbents can be fruitfully
used for the removal of heavy metals with a concentration
range of 20–60 mg/l.
2. The results of using real wastewater showed that rice husk
was effective in the simultaneous removal of Fe, Pb and Ni,
whereas fly ash was effective in the removal of Cd and Cu.
3. It was found that the percentage removal of heavy metals
was dependent on the dose of low cost adsorbent and
adsorbent concentration.
4. The contact time necessary for maximum adsorption was
found to be two hours.
5. The optimum pH range for heavy metal adsorption was
6–7.0.