Study on the regenerable sulfur-resistant sorbent for mercury removal from nonferrous metal smelting flue gas

摘要

In order to remove and recycle elemental mercury from nonferrous smelting flue gas, cobalt sulfide sorbents were synthesized and tested. The mercury adsorption capacity of sorbent at 100 degrees C was 43.03 mg/g with 50% breakthrough threshold. The influences of the flue gas components and reaction temperature on the mercury adsorption capacity were investigated, respectively. The results shown that SO2, H2O, NO and O-2 had negligible impact on mercury adsorption of sorbents. Transmission electron microscopy (TEM), X-ray diffractometer (XRD), mercury programmed desorption (Hg-TPD) and X-ray photoelectron spectroscopy (XPS) were employed to characterize the sorbents. The mercury desorption activation energy from the sorbent was calculated based on a model built by the mercury temperature-programmed desorption data. Additionally, the used cobalt sulfide sorbent was regenerated. The results showed that the cobalt sulfide sorbent could maintain good adsorption performance after regeneration during several cycling tests. Therefore, cobalt sulfide is a suitable sorbent for the mercury removal and recycling from nonferrous metal smelting flue gas.