Elemental Mercury Removal from Natural Gas Using Nano-Tio2

Abstract

The study focused on the utilization of titanium dioxide (TiO₂) as a photo-catalyst for the treatment of natural gas contaminated with elemental mercury (Hg⁰). The catalyst was carefully characterized using various physical techniques, including transmission electron microscopy (TEM), energy dispersive X-ray analysis (EDAX), UV-visible diffuse reflectance spectroscopy (DRS), Brunauer-Emmett-Teller (BET), X-ray photoelectron spectroscopy (XPS) , and X-ray diffraction analysis (XRD). The results clearly demonstrated that TiO₂ exhibited outstanding efficacy in oxidizing Hg⁰ when exposed to UV light. This phenomenon was ascribed to the excitation of photoelectrons within the valence band, leading to their transfer to the conduction band, generating photo-induced electrons that acted as reactive agents responsible for converting Hg⁰ into HgO. Notably, the activity of TiO₂ under UV-visible light was significantly lower compared to TiO₂ under UV light. The overall findings indicated that TiO₂ under UV light exhibited the highest removal capacity, measured at 31.74 µg/g, followed by TiO₂ under UV-visible light at 25.91 µg/g, and TiO₂ in the dark at 20.89 µg/g. The study underscores the promising potential of TiO₂ photo-catalyst for effectively eliminating Hg⁰ contamination in natural gas.