Adsorption characteristics of sericite for nickel ions from industrial waste water

Sericite was used as an adsorbent to efficiently remove Ni(II) from actual industrial wastewater which has Na(I) of high concentration. The removal efficiency for Ni(II) could not be affected by Na(I) which generates ionic strength and the highest removal efficiency was about 93% at pH 7.5. The silanol (SiO2) and aluminol (Al2O3) groups in sericite are likely to play important role in adsorption process. All adsorption process was completed in 120 min and removal efficiency of sericite was higher than that of Amberlite IR 120 plus resin. The effect of temperature on the removal efficiency of Ni(II) was negligible. Also, to investigate the surface condition and functional groups of sericite, SEM (Scanning electron microscopy) photograph, EDX (Energy dispersive X-ray) spectrum, and FT-IR spectrum were applied. In addition, previously adsorbed Ni(II) onto sericite could be easily and completely eluted by HNO3.