关键词: 环境工程, 硝酸盐, 纳米铁, 脱硝, 化学动力学

Abstract: The nanoscale αFe particles with size of about 80 nm was prepared with a microemulsion method. This kind of Fe particles is characterized by high surface energies, removes mostly 30,50,80,120 mg/L of NO-3N within a reaction period of 30 min under room temperature, neutral, and anaerobic conditions. The nitrate reduction rate is larger than 90%. Experiments show that during the reaction the \[NO-3\] decreases monotonously, the \[NH+4\] increases monotonously, while the concentration of the intermediate species \[NO-2\] increases firstly,achieving the maximum value and then decreases, implicating the character of the consecutive reaction instead of the first order reaction. It was suggested that the role of nanoscale iron in the denitrification lies in the directly participaing in the redox reaction accompanied by the adsorption of nitrate, and the major product of the reaction is amonium nitrate.

Key words: environmental engineering, nitrate, nanoscale iron, denitrification, chemical kinetics