Removal of heavy metals using treated- waste material (Moringa oleifera seed pods)

Abstract

The use of waste materials as low-cost adsorbents is attractive due to their contribution in the reduction of costs for waste disposal, therefore contributing to environmental protection and most importantly, offers an attractive potential alternative to conventional methods of removal of toxic ions from the environment. A study to investigate the possible use of powdered Moringa oleifera seed pods (MOSP) was conducted. Removal of selected metal ions were studied including Pb, Cd, Cu, Fe and Zn. Quantification of the extracted metal ions was done using flame atomic absorption spectroscopy (FAAS). One variable at a time optimization method was employed. Using 50 mL of aqueous sample prepared from the metal standard, the optimized parameters were 60 minutes contact time, 1 g of powdered MOSP, pH 8, 100 µm particle size and at 35°C. To determine the functional groups in the sorbents, Fourier Transform Infrared spectroscopy (FTIR) was used. SEM-EDX was used to determine the morphology and the elemental analysis of the sorbents. The optimized parameters were applied on aqueous water samples and the efficiency was in the range of 65.9 ±3.5 to 99.6 ± 6.69%. Moringa oleifera seed pods were proposed as a cheap, simple and an effective alternative for purification of water contaminated with metals.