The behaviors of removing silver ions by low-cost expanded rice husk, nature diatomite and nature bentonite as sorbents

Low cost industrial and agricultural by-products are promising materials for water pollution treatment such as removal of heavy metals. This work deals with removal of silver ions from solutions using expanded rice husk (ERH), nature diatomite (ND) and nature bentonite (NB). Firstly the influence of pH value of the solution on adsorption capacity for silver ions was studied, and then the effect of initial silver concentration on adsorbents adsorption capacity was investigated. The silver ions removal percentage increases with initial pH and achieves a maximum value of nearly 94% at pH= 5.0 +/- 0.5 for ERH. The maximum adsorption capacity is 18.6 mg/g for ERH.