Arsenic removal from aqueous solution using pyrite

Arsenic is one of the major pollutants and a worldwide concern because of its toxicity and chronic effects on human health. This investigation presents the results of arsenic adsorption onto four adsorbents such as pure pyrite, waste pyrite, dried waste pyrite and ground dried waste pyrite. The findings show that the addition of 5 g/L ground dried waste pyrite into the solution proved a high arsenic removal efficiency, with the ability to reduce the concentration of As(V) in the aqueous solution from an initial value of 10 mg/L to 10 μg/L at pH 5. The pH range of 4-6 for ground dried waste pyrite is effective to adsorb arsenic from solution. It is found that oxidation and the particle size of the pyrite has a big influence on arsenic removal. Following the adsorption, the separation of the adsorbent from the liquid phase was achieved using flotation and flocculation methods. Both methods were found to be effective for removing arsenic loaded pyrite from the solution. Test results were confirmed using arsenic containing process water sample to remove arsenic. 15 g/L of pyrite addition provided 99% arsenic removal at pH 5. The arsenic concentration was decreased from the as received 38.5 mg/L to 0.03 mg/L. High arsenic uptake capability and cost-effectiveness of waste pyrite make it potentially attractive for arsenic removal.