Study of adsorption of lead ions from wastewater by polyaniline coated Bel leaf powder in a packed Bed

Abstract

Bio sorbents are commonly used inremoving toxic heavy metal ions from wastewater. Bel leaves are used in temples and immersed in water after offering prayers since ancient times. In the present study, a packed bed continuous column was used to remove lead ions from contaminated water with modified bel leaf powder. The bel leaf powder was polymerised during in-situ polymerisation of aniline in the presence of strong oxidant at low temperature. This modified polyaniline coated bel leaf powder had more capacity to adsorb lead ions. It adsorbed 97.6% lead ion as compared to 90% adsorbed by raw bel leaf powder. Packed column dynamics were also studied for different flow rates (5-25 mL/min) of the adsorbate at different depths along the column. Clogging of the pores and channelization was observed along the column with passage of time, which led to change in lead ion concentration, % removal, adsorption capacity and time of exhaustion along the length of the column. Maximum lead ion removal obtained was 19.1mg, 18.7 mg, 18.36 mg and 18.05 mg at the ends of sections S1, S2, S3 and S4. The exhaustion time was 46 mins, 51 mins, 61 mins and 70 mins respectively for sections S1, S2, S3 and S4. Desorption study showed 96.3% desorption of lead with 0.1 M HCl as eluent.