Journal of Bioprocessing & Biotechniques

Column Biosorption of Lead, Cadmium, Copper, and Arsenic ions onto Algae

Abstract

Abbas H. Sulaymon, Ahmed A. Mohammed and Tariq J. Al-Musawi

A mixture of green and blue-green algae was used as an adsorbant material for biosorption of lead, cadmium, copper, and arsenic ions in fluidized bed reactor. Batch experiments showed that the algal biomass was successfully used for the removal of these metal ions from wastewater. The maximum percentage removal for 1 g dose was 89, 82, 79, and 70 for Pb²⁺, Cu²⁺, Cd²⁺ and As³⁺, respectively. The experimental data fit well to an ion exchange equilibrium model. Affinity constants were calculated for each metal. A higher affinity of the biomass towards lead (Pb²⁺) was observed due to the high electronegativity of this metal. FTIR analyses showed that hydroxyl and carboxyl groups could be very effective for capturing these metals. An ideal plug flow model was adopted to characterize the fluidized bed reactor and solved numerically using MATLAB version (R2009b), which fit well to the experimental breakthrough data. The effects of different operating conditions such as: static bed height, superficial velocity and particle diameter on the removal process were investigated. Lead showed the largest operating time compared with others.