Removal of nickel from aqueous solution using synthesized IL/ZnO NPs

In this paper, the removal of nickel from aqueous solution was studied using zinc oxide nanoparticles (ZnO NPs) and zinc oxide nanoparticles functionalized ionic liquid (IL/ZnO NPs) by batch adsorption and solid phase extraction (SPE) methods, respectively. The synthesized IL/ZnO NPs was characterized by FT-IR, SEM, XRD, XPS, and DLS techniques. The optimum conditions were experimentally determined by varying the parameters such as feed concentration, contact time, adsorbent dosage, pH, and temperature using both the adsorbents. From the optimum conditions, it was found that the feed concentration is 10 ppm, contact time is 120 min, adsorbent dosage is 0.2 g, pH is 6, and temperature is 60 °C with the maximum percentage removal of 81% for ZnO Nps, whereas, for IL/ZnO NPs, the feed concentration is 10 ppm, contact time is 90 min, adsorbent dosage is 0.1 g, pH is 6, and temperature is 60 °C with the maximum percentage removal of 92.5%. On comparison with the results, IL/ZnO NPs was an efficient adsorbent for the removal of nickel from aqueous solution as well as the effluents of electroplating and stainless steel industries. The percentage removal of nickel was analyzed by inductively coupled plasma-optical emission spectrometry (ICP-OES). The sorbents were regenerated and reused effectively.