Aqueous Phase Removal of Heavy Metals from Contaminated Wastewater using Agricultural Wastes

Abstract

This study determined the presence of heavy metals in contaminated wastewater and examined their removal using agricultural wastes as bio-sorbent. Heavy metals contamination in wastewater causes severe adverse effects on human health. Huge amounts of corn cob and wheat bran are produced from maize and wheat plantations every year. The efficacy of raw corn cob (CC) and raw wheat bran (WB) were also tested for the removal of cobalt(II) and nickel(II) from metal solution and contaminated wastewater. The agricultural wastes (bio-sorbent) were characterised with Fourier transform infrared and X-ray florescence spectroscopic techniques. The FTIR result confirmed the interaction of (O-H, C-O and C-H) in (CC and WB) with heavy metals while the XRF result revealed that, both (CC and WB) contain high percent of K2O.The batch sorption technique was conducted at room temperature. The method was applied for the removal of cobalt and nickel using Katsina youth craft village (KYCV) and Gambarawa paint cottage (GPC) contaminated wastewaters. The Microwave Plasma Atomic Emission Spectrometer (MP-AES) result revealed that corn cob is more effective removing Co(II) with (97%) removal efficiency and (77.6 mg/g) bio-sorption capacity in metal solution, (92% and 29.4 mg/g) and (80% and 3.2 mg/g) removal efficiency and bio-sorption capacity using (KYCV and GPC) contaminated wastewater while wheat bran is more effective in removing Ni(II) with (95% and 76 mg/g) removal efficiency and bio-sorption capacity from metal solution. This can serve as a cost effective and greener approach to utilize the agricultural wastes without any chemical treatment, making it user friendly bio-sorbent. From the findings of this study, concluded that corn cob and wheat bran can be used as cheap and safe bio-sorbents for uptake of cobalt and nickel from contaminated wastewater.