Studies on Use of Sand-Bentonite and Sand-Fly Ash Mixtures as Prospective Liner Materials to Retain Iron and Copper in Aqueous Solutions

Abstract

The main aim of the present work has been to understand the retention behavior of metal ions of copper and iron by mixtures of sand bentonite and sand fly ash in the context of their use as liners for waste disposal facilities. Fine sand containing high silica, bentonite, fly ash mixtures have been used to study the sorption behavior. Batch adsorption studies were carried out to estimate the adsorption capacities of two different soil mixtures namely Sand- Bentonite (SB) and Sand Fly ash (SF). It was found that at different Soil to Liquid ratios (S/L) sand bentonite mixture with 20% bentonite sorbs the higher amount of copper whereas sand fly ash mixture with 10% fly ash sorbs the higher amount of iron. Similarly at different initial concentration 20% sand bentonite mixture sorbs the higher amount of copper whereas 10% sand bentonite mixture sorbs the higher amount of iron. Sorption/adsorption isotherms were also established for the experimental data, which indicate that adsorption of heavy metal ions on to SB and SF were favorable.