Mozambique Tilapia Fish Scales as Potential Biosorbent for Zn and Pb Ions Removal: Kinetic and Isotherm Studies

The toxicity and presence of heavy metals in wastewater pose environmental-disposal problems because of their non-biodegradability and persistence in the environment. Heavy metals in wastewater were removed by using physical, chemical and biological treatment. Biosorption is one of the biological treatments emerging as an alternative environmental friendly technology for the removal of metal ions from aqueous solutions. The present study reports the use of Mozambique Tilapia (MTilapia) fish scales to remove zinc (Zn) and plumhum (Pb) ions in wastewater. The characteristics of the fish scales were studied by X-ray fluorescence (XW) spectroscopy, scanning electron microscopy (SEM), and Fourier-transform infrared (FTIR) spectroscopy analyses before and after biosorption. XRF analysis before biosorption showed the presence of calcium oxide, which confirmed the high-efficiency biosorption of Zn and Pb ions. SEM analysis revealed bright bulky particles that indicated the presence of Zn and Pb ions. FTIR analysis verified that the carbonyl, nitro, and amine groups in the absorbent played important roles in the reduction of Zn and Pb ions. The results also show that optimum condition of Zn ion was best selected in domestic wastewater. Langmuir and pseudo-second-order models exhibited the best fit data for isotherm and kinetic study. All these results indicated that biosorption using M.Tiiapia fish scales is a promising method of removing Zn and Pb ions from domestic wastewater.