Removal of aluminum from some water samples by sorptive-flotation using powdered modified activated carbon as a sorbent and oleic acid as a surfactant.

Bench-scale experiments were conducted in the laboratory, aiming to remove aluminum from water. They were based on using powdered activated carbon (PAC), which was prepared from olive stones generated as plant wastes and modified with an aqueous oxidizing agent as HNO3 as an effective sorbent and oleic acid (HOL) as a surfactant. The main parameters (namely: initial solution pHs, sorbent, surfactant and aluminum concentrations, shaking time, ionic strength and the presence of foreign ions) that influence the sorptive-flotation process were examined. Good results were obtained under the optimum conditions, according to which nearly 100% of aluminum, at pH 7 and at room temperature (approximately 25 degrees C), was removed. The procedure was successfully applied to recover aluminum spiked to some natural water samples. Moreover, a sorption and flotation mechanism is suggested.