Phragmites australis Heavy Metal Adsorption

This research utilized analytical-grade chemicals and distilled water solution preparations. Tetraamminecopper(II) sulfate monohydrate ([Cu(NH₃)₄]SO₄·H₂O) was procured from Sigma-Aldrich (St. Louis, MO, USA). A 500 mg/L Ni(II) stock solution was prepared by dissolving nickel dichloride (NiCl₂) in distilled water, and working solutions were subsequently diluted from this stock. The pH value was adjusted using 0.1 M hydrochloric acid (HCl) and 0.1 M sodium hydroxide (NaOH). Sodium chloride (NaCl) was employed to adjust the ionic strengths. Phragmites australis was harvested from Baiyun Lake (117.40 °E, 36.86 °N, Shandong Province, China) and washed five times with distilled water. Then, Phragmites australis was dried at 105 °C for 48 h to a constant weight and then comminuted into fragments (0.45–1.0 mm).