Impregnating Activated Carbon with Iron Salts to Increase Hydrogen Sulfide Removal

Abstract

Hydrogen sulfide (H₂S) emissions from landfills negatively impact surrounding communities. In addition to an unpleasant, rotten-egg odor, inhalation of the gas can cause respiratory distress and irritation. Peak emissions are released from C&D landfills through the decomposition of gypsum drywall. Current removal technologies are costly and often ineffective. The goal of this research was to develop a cost-effective mat geared toward H₂S removal. Preliminary research revealed an increase in adsorption capacity through the addition of iron salts, FeCl3 and FeSO4, to activated carbon at a 5:1 carbon to iron ratio. To evaluate the effect of heat treatments on iron oxide formation, and subsequent adsorption capacity, samples were divided into heat treatment groups of 250ºC, 450ºC, and 650ºC. Samples were flushed with 100 ppm of H₂S under N₂ at 250 ml/min for two hours. Over this time duration, samples subjected to higher temperature heat treatments showed increased adsorption capacity. All heat treated samples demonstrated higher adsorption compared to the baseline non-heat treated samples. Additional research will be conducted to assess the effect of heat treatments above 650ºC.