Toxicologia Ambiental e Analítica

Biosorption of Heavy Metals from Fertilizer Industrial Waste Water Using Rice Husk (RH) and Groundnut Husk (GH) Powder in a Packed Bed Bioreactor

Abstract

Nzelibe HC and Ibrahim KLC

Groundnut husk (GH) and Rice husk (RH) were used as adsorbents to remove Mn2+, Zn2+ and Pb2+ ions from fertilizer industrial waste water. Continuous adsorption experiment was conducted to examine the effect of adsorbent mass, pH, temperature and adsorbent combination on adsorption of Mn2+, Zn2+ and Pb2+ from fertilizer industrial waste water. The results showed that the adsorption of the metal ions was adsorbent mass, pH, and temperature dependent. The optimum adsorbent mass was 60 g, optimum pH was pH 5 and pH 6 and optimum temperature was 60°C for adsorption of heavy metal ions. The Langmuir biosorption isotherm provided the best fit for sorption of Mn2+, Zn2+ and Pb2+ using groundnut husk as indicated by their correlation coefficient (R2) of 0.998, 0.676 and 0.297 while the freundlich biosorption isotherm had the best fit using rice husk as indicated by their correlation coefficient (R2) of 0.332, 0.041 and 0.556 for Mn(II), Zn(II) and Pb (II) respectively. The study also showed that groundnut husk and rice husk can be efficiently used as low cost alternative for removal of Mn2+, Zn2+ and Pb2+.