Removing H2S gas from the air stream using zeolite ZSM-5 substrate impregnated with magnetite and ferric nanoparticles

Introduction: Hydrogen sulfide (H2S) is a toxic gas that has adverse effects on human health and equipment. One of the methods for eliminating of H2S gas is the use of adsorbent substrate. In this study, the effect of adding iron oxides including ferric (Fe2O3) and magnetite (Fe3O4) nanoparticles to ZSM-5 zeolite substrate was investigated on the efficiency of H2S elimination from the air stream. Methods: In this study, Fe2O3 and Fe3O4 nanoparticles were impregnated in ZSM-5 zeolite in two weight ratios of 3% and 5%. The structural properties of the substrate were studied using XRD, BET and SEM. Then, the efficiency of substrate in removing H2S from air was studied while H2S gas was injected in to a pilot setup, in concentrations of 30, 60, 90 and 120 ppm at three bed temperatures of 100, 200 and 300 o C. Results: The accuracy of combination and the morphology of inoculated zeolite was confirmed using XRD and SEM. The BET test also showed that the loading of iron oxide nanoparticles on the substrate educed the substrate surface area. The results revealed that increasing the percentage of nanoparticles and increasing the temperature from 100 ° C to 300 ° C increase the time of breakthrough point. The maximum adsorption capacity was obtained equal to 44.449 (mgH2S/g zeolite) for ZSM-5/Fe3O4-5% substrate at 120 ppm concentration. Conclusion: Iron oxide  nanoparticles  inoculated  in  ZSM-5  zeolite  substrate  increase  the  capability of eliminating of H2S gas at high temperatures and therefore can be used as a suitable method for the elimination of similar pollutants.