Adsorption of nitrilotriacetic acid onto activated carbon prepared by steam pyrolysis of sawdust: Kinetic and isotherm studies

Nitrilotriacetic acid (NTA) adsorption onto sawdust activated carbon was studied. The adsorption process was highly pH dependent and has been explained on the basis of pHzpc and speciation of NTA in aqueous solution. In order to optimize the adsorption process, effect of pH, contact time, adsorbent dose, and ionic strength were studied using batch experiments. Equilibrium studies were performed to evaluate the adsorption capacity and adsorption energy of SDAC for the removal of NTA from aqueous phase. Langmuir model best describes the equilibrium adsorption data than Freundlich model. Ionic strength also played an important role in the process of adsorption and lower ionic strength favoured NTA adsorption. The mechanism of NTA adsorption onto SDAC was explained by inner sphere mechanism.