Synthesis and evaluation of the efficacies of some Schiff bases for the removal of heavy metals from wastewater

Abstract

The Schiff bases, 2-aminoethyl-1,3-diphenyl-3-((2-(piperazin-1- ylethyl) imino) propylidene)-propylethane-1,2-diamine with 89% yield, and 2,2-ethylideneamino)ethyl)phenol-2,2- hydroxybenzalidene) ethyl)acetimedate salt with 91% yield, represented as L₁ and L₂ respectively were synthesized and characterized. Their metal ion removal competences for five heavy metals (Cu, Fe, Co, Cd and Pb) was investigated, in three categories of wastewater obtained from Lambun Dan Lawal (LDL), Kofar sauri (K/sauri) and Youth Craft Village (YCV). The Schiff bases were characterized before and after complexation, by spectroscopic techniques such as Infrared spectroscopy, Molar conductance, UV-Visible, Melting and Decomposition temperature and solubility test. The concentration of the heavy metals both in the wastewater and the complexes was determined by Atomic Absorption Spectroscopy (AAS). The Schiff bases shows outstanding character, by adsorbing/removing most of the targeted heavy metals at variable concentration, especially copper which shows the highest concentration. The results suggested that, the two Schiff bases can be used as an alternative chelating agents, for the removal of heavy metals from wastewater.

Keywords: Schiff base, Wastewater, Heavy metals, Evaluation, Extraction