Adsorption of heavy metals from electroplating wastewater using guinea corn husk activated carbon.

Abstract

This study details the removal of manganese and copper from electroplating wastewater using activated carbon made from Guinea corn husks. Activated carbon prepared from Guinea corn husks using a two-step activation process was characterized using standard analytical methods. The moisture content, ash content, bulk density and electrical conductivity of Guinea corn husk were estimated to be 10.00 %, 0.35 %, 0.33 g/cm3 and 1.5 x 102 µmhos respectively. The adsorbent was used for the adsorption of Cu2+, Zn2+, Fe2+ , and Mn2+ from electroplating wastewater. Results obtained showed that manganese had the highest percentage removal at a dosage of 2g and copper had the lowest percentage removal at a dosage of 2g. The pseudo first-order, pseudo second-order kinetic models were used to evaluate adsorption kinetics for the removal of manganese and copper from electroplating wastewater. The results showed that the pseudo second-order kinetic model best described the adsorption kinetic process. Indicating that chemsorption (chemical adsorption) is the rate determining step during the removal of manganese and copper from electroplating wastewater. Thermodynamic parameters such as ΔH, ΔS and ΔG were studied, the result showed spontaneous and favourable reaction for all the heavy metals.