Synthesis of Fe(NO3)3 and H3PO4 Combined Pelletized Activated Carbon Composites for Removal of Ultrafine Pollutant Gases (NH3, CO2 and H2S)

Abstract

In the present study, the potential of pelletized activated carbon (PAC) inoculated with Fe(NO3)3 and H3PO4 as packing material for NH3, CO2 and H2S removal from mixed waste gases was evaluated. Broad tests were conducted to determine the factors affecting the removal of high concentrations of NH3. The removal characteristics, removal efficiency, and removal capacity of the system were evaluated. The results of bed depth service time experiment suggested that the removal of NH3, CO2 and H2S results from physical adsorption of the gases by pelletized activated carbon. The vigorous steady state of physical adsorption lasted for approximately 4 h. After the system achieved equilibrium, the pelletized activated carbon bed exhibited high adaptation to shock loading, elevated temperatures, and high flow rates. The results also demonstrated that the removal of NH3 was not affected by the presence of H2S. Gas retention time was a crucial factor affecting system performance. A retention time of ≥ 65s was required to obtain NH3 removal efficiencies of ≥ 15 %. The acute loading of NH3 for system was 4.2 gN/m 3 /h and the maximal loading was 16.2 gN/m 3 /h. The results of this study can be used as a guide for the design and operation of industrial-scale systems in the future.