Oxidation of H2S to Elemental Sulfur over Alumina Based Nanocatalysts: Synthesis and Physiochemical Evaluations

Authors

1 Sharif University of Technology

2 Department of Chemical Engineering, Abadan Faculty of Petroleum Engineering, Petroleum University of Technology, Abadan, Iran

3 RIPI

4 Chemical and Environmental Engineering Group, Islamic Azad University, Tehran South Branch, Tehran, Iran

Abstract

In this paper oxidation of the H2S into elemental sulfur over synthesized alumina-based nanocatalysts was physiochemically investigated and the results compared with a commercial Claus catalyst. The wet chemical, co-precipitation and spray pyrolysis techniques employed to synthesize several alumina nanostructures. Then, the SEM, XRD and ASAP analysis methods utilized to characterize in order to choose the best nanocatalyst. The sulfur andH2S contents determined through the standard UOP techniques. Amongst these as-synthesized materials, Al2O3-supported sodium oxide prepared through the wet chemical and Al2O3 nanocatalyst via spray pyrolysis methods were the most active catalysts for the purpose at hand. In addition, the titanium dioxide nanostructure and a hybrid of nano alumina support (made via the wet chemical method) decorated on the carbon nanotube prepared for this goal. Moreover, the statistical design of experiments screening of the significant synthesizing parameters performed through the Box-Behnken (e.g.;Response Surface Methodology (RSM)) technique. Ultimately, the best chemically characterized nanocatalyst was subjected to evaluations in a fixed bed reactor while effects of temperature, metal loading and GHSV understudied. It was observed that, the alumina nanoparticles prepared through the wet chemical and spray pyrolysis methods led H2S into elemental sulfur in a reproducible manner with 97 and 98% conversions, respectively. Both of these were more desirable than that obtained utilizing the commercial catalysts (i.e.: CR-3S and CRS-31) providing nearly 96% conversion.

Keywords