Reduction of [Fe(III)EDTA] catalyzed by activated carbon modified with ammonia solution



NO and SO2 can be removed simultaneously by [Fe(II)EDTA]2− solution. Activated carbon is used to catalyze the regeneration of [Fe(II)EDTA]2− to maintain the NO removal efficiency at a high level for a long time. In this article, ammonia solution has been tried to modify the coconut activated carbon to ameliorate its catalytic capability in the regeneration of [Fe(II)EDTA]2−. Experiments have been made in a batch stirred cell to investigate the effects of modification conditions, such as ammonia concentration, impregnation time, activation temperature, and activation time, on the catalytic performance of activated carbon. The experimental results suggest that the optimal modification condition be illustrated as follow: ammonia concentration 9.0 mol L−1, impregnation time 11 h, activation temperature 700°C, and activation time 4 h. After ammonia modification, the surface area of activated carbon decreases. But the total basicity of activated carbon is enhanced, which plays a vital role in improving the catalytic capability of activated carbon in the reduction of [Fe(III)EDTA]. The activated carbon modified by ammonia solution can get a higher NO removal efficiency than the original activated carbon. © 2013 American Institute of Chemical Engineers Environ Prog, 33: 99–106, 2014