Adsorption of heavy metals using activated carbon produced from municipal organic solid waste

Adsorption of cadmium (Cd2+) and lead (Pb2+) was investigated using activated carbon (AC) produced from municipal organic solid waste (MOSW). The produced AC was characterized using Scanning Electron Microscopy, X-ray Diffraction, Fourier Transform Infrared spectroscopy, and Brunauer-Emmett-Teller. The results showed that an AC with a surface area of 790m(2)/g was produced at carbonization temperature and time of 700 degrees C and 2h, respectively, and activation with phosphoric acid concentration of 30%. The effect of operational factors, namely, pH3-7, contact time (0-480min), metal concentration (25-300mg/L), and adsorbent dosage (25-300mg per 50mL of metal solution) on the adsorption process was investigated. The results showed that optimum adsorption of Cd2+ and Pb2+ were obtained at pH of 5, contact time of 180min, metal concentration of 100mg/L, and adsorbent dose of 200mg per 50mL of metal solution. At optimum operational conditions, removal efficiencies of 78 and 94% for Cd2+ and Pb2+, respectively, were achieved. The isotherms also showed that the maximum adsorption capacity of Cd2+ and Pb2+ were 61 and 90mg/g, respectively, at equilibrium time of 120min and pH value of 5.