(328t) In-Situ Removal of H2S(g) Using Ultradispersed Iron Oxide Nanoparticles

An envisioned application of ultradispersed nanoparticles has to do with the upgrading of oil in-situ, whereupon active surface nano-structures, small enough to breakthrough the reservoir formation, interact with the heavy oil molecules promoting upgrading reactions. A similar approach has been thought to tackle the removal of H₂S produced as a byproduct during in-situ upgrading. The applicability of ultradispersed iron oxide nanoparticles for the absorption of H₂S was, particularly, investigated. A (w/o) microemulsion method was used to prepare the ultradispersed iron oxide nanoparticles. The nanoparticle average diameter, characterized by dynamic light scattering was smaller than 100 nm. As for their reactivity, a semi-batch apparatus was used to determine the H₂S breakthrough curves by monitoring the outlet H₂S concentration while the gas was bubbling through the (w/o) microemulsion holding the nanoparticles. Results showed that stirring had no significant effect on the H₂S absorption. This observation supports the conclusion that dispersion by microemulsion is sufficient to grant intimate contact with the gas. In addition, temperature had no effect on the breakthrough volume, which indicates that reaction kinetics is not limiting.