Adsorption efficiency of hydrogen sulfide using coconut shell-derived activated carbon and iron oxide composites

Hydrogen sulfide (H 2 S) is a toxic gas commonly released from industrial activities, wastewater treatment, and biogas production, posing serious risks to human health and the environment.This study evaluated the adsorption efficiency of H 2 S using coconut shell-derived activated carbon (AC) and iron oxide (FO).A series of experiments were conducted on a continuous laboratory scale adsorption column to examine the effects of adsorbent dosage, contact time, gas flow rate, and mixing ratio.The study results revealed a highest H 2 S adsorption efficiency at the experiment conditions of 1 g material dosage, 60 min adsorption time, 500 mL.min -1 gas flow rate, initial H₂S concentration of 70 ppm, and a mixing ratio of AC:FO = 70:30.The Thomas and Adams-Bohart models were applied to simulate the adsorption process.The Adams-Bohart model indicated that FO had a higher maximum adsorption capacity per unit volume (87.57mg.L -1 versus 7.55 mg.L -1 for AC), suggesting a stronger initial adsorption ability.Further research on the effectiveness of the absorbents under real conditions are necessary.