Removal of copper ions from electroplating effluent solutions with native corn cob and corn stalk and chemically modified corn stalk

Rapid industrialization throughout the world has generated huge volumes of wastes containing toxic materials such as metal ions. The presence of heavy metals in wastewater and surface water is the major concern of the public health and the environment. The aim of this research was to remove the Cu ions from electroplating effluent solutions using biosorbents: corn cob and corn stalk. In addition to use the natural biosorbent, modification of corn stalk by nitric acid was also studied. The surface morphology of adsorbents was observed using a scanning electron microscope. The porous and tubular structure of the corncob and corn stalk indicated their capability in adsorption of metal ions from the solution. In order to study the equilibrium adsorption extent, Langmuir & Freundlich models were used. It was found that the maximum sorption capacity of corn cob was higher than the corn stalk. On the other hand, the modified corn stalk showed higher capacity than both corncob and corn stalk without modification.