H2S Removal Using ZnO/SBA-3: New Synthesis Route and Optimization of Process Parameters

Abstract

H2S is a major toxic compound that could be found in air, water, Fossil fuels and causes some worse effects such as acidic rain and corrosion. In the present work SBA-3 (Santa BarbarA University no. 3) with three different weight percent’s of ZnO, i.e. 5%, 10% and 15% was synthesized via an in situ approach. All synthesized samples were characterized using atomic absorption spectrometry, X-ray diffraction (XRD), nitrogen adsorption and transmission electron microscopy (TEM). The obtained results from XRD and nitrogen adsorption confirmed that all the samples almost retained their ordered structure after incorporation of ZnO nanoparticles within the mesopores of SBA-3. TEM images show that ZnO nanoparticles arranged along the direction of mesopores of SBA-3. Then, adsorption of H2S from a model gas was investigated. A three factor Box–Behnken design with five center points and one response was performed for the evaluation of effect of three process parameters, i.e. ZnO wt%, space velocity and temperature on the adsorption of H2S and a quadratic model (r2 : 0.9185) was developed to navigate the design space. Temperature had the largest and space velocity had the lowest effect on the breakthrough of H2S. The optimum breakthrough time (tbp) was 588 min.