(27f) Adsorption of CO2 and H2S from Natural Gas by Activated Fly Ash

Waste oil fly ash (OFA), a by- product of fossil fuel combustion from power generating plants, was successfully convert to activated carbon using both chemical and physical treatment. A combination of three acids (Sulfuric, nitric and phosphoric acids) was mixed at different volume ratios and concentrations with the ash, followed by physical treatment at 990 oC while CO₂ is introduced at flow rate of 1 L/min.  The produced AC was characterized according to its surface area and morphology.  BET surface area has increased from less than 1 m²/g for untreated ash to 375 m²/g after both chemical and physical activation. Then it is utilized in the removal of CO₂ and H₂S from natural gas stream. The maximum adsorption capacity of the treated ash was found to be 240 mg/g and 175 mg/g, respectively. The adsorption rate increased with the increase in flow rate and concentration. The results indicated the potential of using waste OFA in acidic gases removal from downstream.