REMOVAL OF NITRATE FROM WATER BY MODIFIED ACTIVATED CARBON

G. NUNELL; M. E. FERNANDEZ; P. BONELLI; A. L. CUKIERMAN

Rosario, Argentina

Workshop; 1st Argentinian Workshop in Environmental Science / Taller Argentino en Ciencia Mediambiental; 2009

Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario

A commercially available activated carbon was subject to thermal treatment under N2 flow (100 ml/min) for 60 min at 550ºC. The effect of this treatment has been studied for nitrate removal from an aqueous diluted medium used as model. The surface chemistry was caracterized by the determination of the point zero charge (pHZC), surface functional groups (carbonyl, phenols, lactones, carbonyl) were quantified by the titration method of Boehm using bases of different ionization potential, chemical composition were determined by ultimate analysis. The effect of the treatment on the physical characteristics were determined by N2 adsorption isotherms at 77 K.  Batch experiments at 25 ºC were also carried out in order to evaluate the pH effect on the removal of nitrate ions (100 ppm) from water. In order to evaluate their nitrate adsorption capability , adsorption isotherms of nitrate ion from a model solution were determined and properly described by freundlich model (r2=0.99).  Results obtained indicate that commercial activated carbon thermally treated under N2 flow improve its performance for nitrate removal from aqueous medium, and that the surface chemistry play a key role in nitrate adsorption performance