Adsorbent materials from paper industry waste materials and their use in Cu(II) removal from water.

This paper deals with the removal of Cu2+ from water using adsorbent materials prepared from paper industry waste materials (one de-inking paper sludge and other sludge from virgin pulp mill). Experimental results showed that de-inking paper sludge leads to mesoporous materials (Vmic/VT = 0.13 and 0.14), whereas the sludge from virgin pulp mill produces high microporous adsorbents (Vmic/VT = 0.39 and 0.41). Adsorbent materials were then used for Cu2+ removal from water at acid pH. During water treatment, heavy metals lixiviation from adsorbent materials was not produced. However, important Ca and Mg leaching was observed. Final pH significantly increases after treatment of water with adsorbent materials probably due to their elevated CaCO3 content. In general, highest Cu2+ removal was obtained using adsorbent materials from de-inking paper sludge. This result could be due to their higher content in oxygenated surface groups, high average pore diameter, elevated superficial charge density, high CaCO3 amount and high Ca and Mg exchange conten