Developing Sustainable Innovation From Maize Husks for the Remediation of Soil and Water Polluted by E-Wastes. Case Study: The Evacuated Landfill Site at Owerri, Imo State, Nigeria

Abstract

A novel and less cost effect remediation strategy was designed to meet the challenges posed by e-waste in parts of Owerri in Imo State of Nigeria. This followed the determination of the levels of contamination of the environment within a recently evacuated landfill site (dumpsite) in Owerri Imo state, Nigeria by the leaching of heavy metals from e-wastes. The analysis was necessitated as people were already settling very close to the site and cultivating plants for human consumption without prior examination of the vicinity and subsequent remediation of the polluted site. The Energy dispersive X-Ray Fluorescence (EDXRF), Atomic Absorption Spectroscopy (AAS) and the Pollution Index (PI) were used on randomly collected soil from the evacuated landfill site to obtain first, an overview, then the concentration of heavy metals present in the soil. The following heavy metals from the landfill site were highlighted: Pb, Ni, Zn, Cd, Cr, Cu, As and Fe and the level of the presence of each confirmed. Atomic Absorption Spectroscopy (AAS) was also used to determine the concentrations of the heavy metals in a shallow well located very close to the site. The concentration of lead and cadmium were hazardously found to fall above the World Health Organization (2003) standard in both the soil and shallow well. Lead for example was found to be 24.20mg/kg in the soil and 0.230mg/L in the shallow well as against 0.70mg/kg permissible in Nigeria. The lead and cadmium ions apparently leached from everyday electronic materials (e-wastes) dumped in the landfill site as these e-waste materials abound in the said site and area. A research was therefore carried out to assess the removal or reduction of lead(II) ion and Cadmium(II)ion in the polluted shallow well water by some maize wastes - from maize/corn husks biomass. The efficiency of this novel research is high as the biomass part before and after adsorption of Pb2+ and Cd2+using Fourier Transform Infrared Spectra showed that the waste maize part (husks) have available functional groups and as a result, active sites for the adsorption of Cd2+and Pb2+. This research is relevant particularly to all those living around the vicinity and to the Government Scientists who would need to speed up the remediation of the area and create a safe e-waste disposition method.