Adsorbents for iron removal obtained from vermiculite

In presented work, raw, expanded and acid treated vermiculites were used as low-cost and active adsorbents for reducing o f environmental pollution with heavy metals. Acid treatment was performed at elevated temperature (95°C) for 2 and 24 h in solution of HNO 3 . Adsorption capacity towards Fe 3+ was studied in column, semi- b atch and batch mode. It was shown that all samples are effective in removal of heavy metals; however adsorption mechanism is based not only on ion exchange o f interlayer cations but also precipitation/ deposition processes. Starting material a nd modified samples as well as spent adsorbents were characterized with respect to the vermic ulite structure using X-ray diffraction metho