Comparative Study of Hydrogen Sulfide Adsorption by using Alkaline Impregnated Activated Carbons for Hot Fuel Gas Purification

Biogas, natural gas, and synthesis gas from coal gasification contain hydrogen sulfide (H2S) that is highly toxic for human and corrosive for machine. H2S must be removed from fuel gases prior utilization. The objective of this research was to compare the adsorption of H2S by using commercial and alkaline impregnated activated carbons. The commercial and alkaline impregnated activated carbons were tested by the temperature program adsorption of H2S at 30 °C and 550 °C. At high temperature of adsorption, alkaline activated carbons adsorbed H2S significantly higher than commercial activated carbon (in the range of 3-29 times higher depending on modification method). Furthermore, the concentration of H2S came out at the outlet gas after treated by the KOH and Na2CO3 impregnated activated carbons was less than 30 ppmv, which was safe for utilizing in mechanical and power engine.