In this study, pistachio hull waste (PHW) powder was added to sand column filtration systems as a natural adsorbent to increase HMs removal from contaminate river water. First, the characterization of PHW before and after Pb adsorption was determined using SEM, EDX, XRD, FTIR, BET and proximate analysis. Then, the HMs adsorption capability of PHW was investigated through batch experiments using polluted synthetic water with Pb, Cu, Co and Ni. Ultimately, fixed-bed column experiments were performed using real polluted river water. The characterization analyses proved that PHW has high HMs adsorption capability due to containing active functional groups and high surface area (4.0218 m2 g−1). Based on the batch experiments, 45 mg of PHW could remove Pb, Cu, Co and Ni up to 87 %, 73 %, 69 % and 88 % in 60 min. According to the fixed-bed column experiments, sand modification with PHW increased the HMs removal. The breakthrough curves suggested adding 5 g kg−1 PHW to sand column (H = 15 cm, Q = 5 mL min−1) could increase the exhaustion time approximately from 400 min to 800 min. The Thomas and Yoon-Nelson models showed the best match with the experimental data. Our finding suggests a promising and environmental friendly method for HMs removal from surface water.

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