The ability of bio-sludge for removal cadmium (Cd2+) contaminated synthetic wastewater

Cadmium is a heavy metal that used in various industries. That causes wastewater contaminated with Cadmium into the environment. Cadmium is a heavy metal that affects human health. This led to the study of heavy metal removal in wastewater. The biosorption is one effective and eco-friendly method of treating cadmium. Therefore, bio-sludge from wastewater treatment plant was utilized and used in this study.  This laboratory experiment aimed to study the ability of living and dead microorganisms for removal cadmium wastewater. The results showed cadmium removal efficiency of living and dead microorganisms were higher than 90%. While, living microorganisms showed higher cadmium uptake than dead microorganisms because living microorganisms involves adsorption to cell wall and intracellular accumulation. The study of pH value shows that living microorganisms have the ability for removal cadmium contaminated synthetic wastewater at pH 4-6. When there was increasing the initial cadmium concentration, the bio-sludge's heavy metal adsorption capacity increased. Nevertheless, the cadmium removal efficiency decreased when initial cadmium concentration increased to 50 mg/L.