Removal of heavy metal ion concentrations from the wastewater using tobacco leaves coated with iron oxide nanoparticles

Abstract

Adsorption of chromium (VI), lead (II) and zinc (II) metal ions from the industrial effluent by tobacco leaves coated with iron oxides was investigated using continuous fixed bed column. The nano-adsorbent material is prepared by chemical synthesis technique capped with iron oxide nanoparticles, and its characteristics are analysed by various surface morphological methods. Breakthrough analysis of the column was examined by varying the adsorbate concentrations, height of the adsorbent bed and rate of flow. The maximum adsorption efficiencies of chromium (VI)–92.26%, lead (II)–75.57% and zinc (II)–89.36% were observed with 5 mL/min of optimum flow rate, bed height of 10 cm and metal ion concentration of 100 mg/L. Kinetic models such as Thomas, Yoon-Nelson and bed depth service time were fitted with best correlation (R2 > 0.95) values in this adsorption process. Overall performance of the column was evaluated by desorption studies, and regeneration of adsorbent in the column was also done by adding concentrated hydrochloric acid (0.3 M).